Patent Publication Number: US-10789445-B2

Title: Fingerprint sensing display apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority of Republic of Korea Patent Application No. 10-2017-0183211 filed on Dec. 28, 2017, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference in its entirety. 
     BACKGROUND 
     Technical Field 
     The present disclosure relates to a display device capable of fingerprint recognition. Specifically, the display device is capable of recognizing a fingerprint using an ultrasonic technique by placing an ultrasonic fingerprint sensor under the rear surface of an electroluminescence display panel such that the electroluminescence display panel becomes a transmission and reception channel of the ultrasonic signal. 
     Related Technology 
     Referring to  FIG. 1 , a conventional fingerprint sensor  14  is attached to the periphery of the liquid crystal display panel  11  of the conventional display device  10  to support a fingerprint recognition function. The conventional display device  10  includes a liquid crystal display panel  11 , a fingerprint sensor  14  disposed around the liquid crystal display panel  11  so as to be exposed to the environment, a first speaker  12  and a second speaker  13 . It has been difficult to make the conventional display device  10  with a narrow bezel due to the fingerprint sensor  14  and the speakers  12  and  13 . Therefore, it has been difficult to increase the display area ratio of the display panel  11  of the display device  10 . 
     SUMMARY 
     The present disclosure describes an electroluminescence display panel capable of displaying a superior image quality. The electroluminescence display panel includes an electroluminescence element. 
     In particular, an ultrasonic sensor is disposed under the rear surface of the electroluminescence display panel. The electroluminescence display panel may include an organic light emitting diode (OLED) and/or a quantum-dot light emitting diode (QLED). 
     By placing fingerprint sensor under the rear surface of an electroluminescence display panel, a fingerprint recognition function can be provided by touching a user finger on a display area or a cover glass on a display area through an electroluminescence display panel. Further, in such case, a width of the bezel of the display device including the electroluminescence display panel can be minimized, thereby maximizing the area of the electroluminescence display panel of the display device. 
     Further, an ultrasonic signal can be used for recognizing a fingerprint through an electroluminescence display panel, and sensitivity of the ultrasonic signal may be reduced for various reasons. In addition, when the sensitivity of the ultrasonic signal reduced, the recognition success rate may be lowered, and the fingerprint recognition speed may be lowered, so that the user may experience a slow response speed. 
     In order to perform fingerprint recognition through an electroluminescence display panel, the frequency of the ultrasonic signal of the fingerprint sensor may be at least 10 MHz and if the frequency of the ultrasonic signal is in such a high frequency band, the sensitivity of the ultrasonic signal can be reduced according to the density or the Young&#39;s Modulus of the respective elements, and/or thickness of the respective elements. 
     An image quality of the electroluminescence display panel and/or the sensitivity of the fingerprint sensor may be degraded due to electromagnetic interference (EMI) generated between the fingerprint sensor and the electroluminescence display panel. 
     When the fingerprint sensor is attached to the electroluminescence display panel, the flatness of the substrate of the electroluminescence display panel may be deteriorated by the stress applied to the substrate of the electroluminescence display panel by the fingerprint sensor. Accordingly, a pressed mark of the electroluminescence display panel may be visible. 
     When the fingerprint sensor is disposed on the rear surface of the electroluminescence display panel, the light-shielding level at the rear surface of the electroluminescence display panel may vary according to the fingerprint sensor arrangement. Thus, the characteristics of the display panel may be varied accordingly. Therefore, a stain defect, for example, a shadow-mura may occur. 
     When the fingerprint sensor is disposed on the rear surface of the electroluminescence display panel, the heat radiation characteristic of the rear surface of the electroluminescence display panel may vary according to the arrangement of the fingerprint sensor and an image retention may be generated in a displayed image due to the temperature deviation of the electroluminescence display panel. 
     Accordingly, it is an object of the present disclosure to provide a structure of a display device capable of improving above-mentioned problems, in which an ultrasonic fingerprint sensor disposed on the rear surface of an electroluminescence display panel. 
     Accordingly, an object of the present disclosure is to provide a structure of a display device capable of overcoming the above-mentioned problems and improving various problems that may degrade the image quality of the electroluminescence display panel, thereby improving the sensitivity of the ultrasonic sensor signal and improving the speed of fingerprint recognition. 
     It should be noted that the objects of the present disclosure are not limited to those described above and other objects of the present disclosure included in the following descriptions can be clearly understood by those skilled in the art from the following description. 
     In one embodiment, a display device comprises: a substrate including a display area that comprises a fingerprint recognition area for recognizing a fingerprint; a plurality of pixels disposed on the substrate; an ultrasonic fingerprint sensor configured to sense a fingerprint, the ultrasonic fingerprint sensor overlapping the fingerprint recognition area and disposed under the substrate; and a pressure sensor configured to sense pressure on the display device, the pressure sensor disposed under the ultrasonic fingerprint sensor. 
     In one embodiment, a display device comprises: an electroluminescence display panel configured to display an image, the electroluminescence display panel including a first surface and a second surface that is under the first surface; a fingerprint sensor positioned under a second surface of the electroluminescence display panel; a pressure sensor configured to sense a pressure applied to the electroluminescence display panel, the pressure sensor positioned under the fingerprint sensor. 
     In one embodiment, a display device comprises: a plurality of pixels on a flexible substrate; a cushion member including at least one opening, the cushion member under the flexible substrate; at least one fingerprint sensor positioned in the at least one opening of the cushion member; and at least one pressure sensor under the fingerprint sensor, the at least one pressure sensor configured to receive a pressure through the cushion member. 
     In one embodiment, a sensor comprises: at least one arrangement means that is attachable to a rear surface of an electroluminescence display panel, the arrangement means providing visual information to a display area of a display device with an arrangement of a plurality of pixel; an ultrasonic transmission and reception electrode structure, the ultrasonic transmission and reception electrode structure using ultrasonic waves for an approval of a user through a display area of the display device; a pressure sensing means under the ultrasonic transmission and reception electrode structure, the pressure sensing means for sensing pressure; and a control unit for processing the ultrasonic waves to recognize a fingerprint of the user. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The above and other aspects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  explains a conventional display device; 
         FIG. 2  is a conceptual diagram schematically illustrating a display device capable of providing a fingerprint recognition function according to an embodiment of the present disclosure; 
         FIG. 3  is a plan view schematically illustrating an electroluminescence display panel of a display device capable of providing a fingerprint recognition function according to an embodiment of the present disclosure; 
         FIG. 4  is a cross-sectional view schematically illustrating a cross section A′-A″ of the display device as illustrated in  FIG. 3  according to an embodiment of the present disclosure; 
         FIG. 5  is a cross-sectional view illustrating a stack structure of an exemplary electroluminescence display panel which can be applied to a cross-section A′-A″ of a display device schematically illustrated in  FIG. 4  according to an embodiment of the present disclosure; 
         FIG. 6  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to another embodiment of the present disclosure; 
         FIG. 7  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 8  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 9  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 10  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 11  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 12  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 13  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 14  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 15  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 16  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 17  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 18  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 19  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 20  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 21  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 22  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 23  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 24  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 25  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 26  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 27  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 28  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 29  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 30  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 31  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 32  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 33  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 34  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 35  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 36  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure; 
         FIG. 37  is a conceptual diagram schematically illustrating a display device capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure; 
         FIG. 38  is a plan view schematically illustrating an electroluminescence display panel of a display device capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure; 
         FIGS. 39A, 39B, and 39C  are cross-sectional views schematically illustrating a cross section B′-B″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure; 
         FIGS. 40A, 40B, and 40C  are cross-sectional views schematically illustrating a cross section C′-C″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure; 
         FIGS. 41A, 41B, and 41C  are cross-sectional views schematically illustrating a cross section D′-D″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure; 
         FIG. 42  is a cross-sectional view illustrating a stack structure of an exemplary electroluminescence display panel which can be applied to a cross-section A′-A″ of a display device according to the other embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Advantages and characteristics of the present disclosure and a method of achieving the advantages and characteristics will be clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiment disclosed herein but will be implemented in various forms. The embodiments are provided by way of example only so that a person of ordinary skilled in the art can fully understand the disclosures of the present disclosure and the scope of the present disclosure. Therefore, the present disclosure will be defined only by the scope of the appended claims. 
     The shapes, sizes, ratios, angles, numbers, and the like illustrated in the accompanying drawings for describing the various embodiments of the present disclosure are merely examples, and the present disclosure is not limited thereto. Like reference numerals generally denote like elements throughout the specification. Further, in the following description of the present disclosure, a detailed explanation of known related technologies may be omitted to avoid unnecessarily obscuring the subject matter of the present disclosure. The terms such as “including”, “having” and “consist of” used herein are generally intended to allow other components to be added unless the terms are used with the term “only”. Any references to singular may include plural unless expressly stated otherwise. 
     Components are interpreted to include an ordinary error range (e.g., a tolerance range) even if not expressly stated. 
     When the position relation between two parts is described using the terms such as “on”, “above”, “below”, and “next”, one or more parts may be positioned between the two parts unless the terms are used with the term “immediately” or “directly”. 
     When an element or layer is disposed “on” other element or layer, another layer or another element may be interposed directly on the other element or therebetween. 
     If it is described that a component is “connected” or “coupled” to another component, it is understood that the component is directly connected or coupled to the other component but another component may be “connected” or “coupled” between the components. 
     Although the terms “first”, “second” and the like are used for describing various components, these components are not confined by these terms. These terms are merely used for distinguishing one component from the other components. Therefore, a first component to be mentioned below may be a second component in a technical concept of the present disclosure. 
     Like reference numerals refer to like elements throughout the specification. 
     A size and a thickness of each component illustrated in the drawing are illustrated for convenience of description, and the present disclosure is not limited to the size and the thickness of the component illustrated. 
     Each of the features of the various embodiments of the present disclosure can be combined or combined with each other partly or entirely. Those skilled in the art will understand that the features of the various embodiments can be technically interlocked and driven as well. The features of the various embodiments can be practiced independently or in conjunction with each other independently of each other. 
     Hereinafter, various embodiments of the present disclosure will be described in detail with reference to accompanying drawings. 
       FIG. 2  is a conceptual diagram schematically illustrating a display device capable of providing a fingerprint recognition function according to an embodiment of the present disclosure. 
     Referring to  FIG. 2 , a display device  100  according to an embodiment of the present disclosure will be described. 
     The display device  100  according to an embodiment of the present disclosure may include an electroluminescence display panel  110  and a case supporting the electroluminescence display panel  110 . 
     Various components may be placed inside the case of the display device  100 . For example, speakers  12 ,  13 , a battery, a printed circuit board, an antenna, a sensor, and/or a camera may be disposed. However, the present disclosure is not limited thereto. 
     The electroluminescence display panel  110  is configured to include a fingerprint recognition area (FDA) configured to recognize or to detect a fingerprint of a finger that is touched when a user&#39;s finger touches a specific area of the electroluminescence display panel  110 . Accordingly, the display device  100  according to an embodiment of the present disclosure can recognize a fingerprint by inputting a touch to the electroluminescence display panel  110 . Thus, the fingerprint recognition area FDA may refer to a particular area of the electroluminescence display panel  110  configured to detect the fingerprint. According to the embodiments of the disclosure, the fingerprint recognition area FDA may be realized at one or a plurality of different positions of the electroluminescence display panel  110  as well as the area corresponding to the home button as illustrated in  FIG. 1 . 
     Therefore, the display device  100  (i.e., the apparatus) can detect the fingerprint through the electroluminescence display panel  110  and may provide various security functions. Since a separate fingerprint sensor can be omitted from the bezel area of the display device  100 , the display area ratio of the electroluminescence display panel  110  in the display device  100  can be maximized. 
     For convenience of explanation, the ultrasonic fingerprint sensor of the ultrasonic type will be referred to as a fingerprint sensor. 
     Various user interfaces (UI) corresponding to the fingerprint recognition operation may be displayed in the fingerprint recognition area FDA through a plurality of pixels. 
     For example, for a short message service (SMS) reception notification window, the fingerprint recognition function may be activated such that a fingerprint recognition position may be displayed for a user and a guidance message for finger contact may be displayed. The fingerprint recognition process can be performed to support various user authentication functions, and it can be applied to functions such as security access, online payment, and user registration. If a plurality of fingerprint sensors is placed at various positions of the electroluminescence display panel  110 , different functions may be provided for each fingerprint recognition position. 
       FIG. 3  is a plan view schematically illustrating an electroluminescence display panel of a display device capable of providing a fingerprint recognition function according to an embodiment of the present disclosure. 
     Referring to  FIG. 3 , an electroluminescence display panel  110  of the display device  100  according to an embodiment of the present disclosure will be described. 
     The electroluminescence display panel  110  according to an embodiment of the present invention may be configured to include a plurality of pixels PXL. The region where the plurality of pixels PXL is arranged may be defined as a display area AA. The area other than the display area AA or the peripheral area of the display area AA may be defined as the non-display area NA. 
     In the non-display area NA, a driving unit for driving the plurality of pixels PXL is disposed. The driving unit may include a gate driver for supplying a scan signal to the switching transistor of the pixel PXL and a data driver for supplying a video signal to the data line. 
     The pixel PXL of the electroluminescence display panel  110  may include an electroluminescence element that displays a specific color. For example, the pixel PXL may be configured to include red, green, and blue electroluminescence elements, or may be configured to include red, green, blue, and white electroluminescence elements, or may be configured to include red, green, blue, and green electroluminescence elements. 
     The pixel PXL may include at least a switching transistor, a driving transistor, and a storage capacitor. 
     The switching transistor is turned on when a scan signal is supplied to the scan line, and supplies the data signal supplied to the data line to the gate electrode of the driving transistor and the storage capacitor. 
     The driving transistor controls the current supplied to the electroluminescence element according to the data signal, which is a video signal supplied to the gate electrode of the driving transistor, and a high potential voltage supplied from a high potential power supply line, thereby controlling the brightness of light emitted from the electroluminescence element. Even if the switching transistor is turned off, the driving transistor may supply the current until the data signal of the next frame is supplied by the potential difference charged in the storage capacitor, so that the electroluminescence element may maintain the light emission. The electroluminescence element may be an electroluminescence diode, and the electroluminescence diode may include an anode electrode, an electroluminescence layer corresponding to the anode electrode, and a cathode electrode corresponding to the electroluminescence layer. The cathode electrode may be configured to receive a low potential voltage from a low potential power supply line. 
     Ultrasonic waves generated from the fingerprint sensor are transmitted to the fingerprint recognition area FDA set in the display area AA. The fingerprint sensor may be configured to detect a fingerprint by sensing ultrasonic waves reflected from the finger. 
       FIG. 4  is a cross-sectional view schematically illustrating a cross section A′-A″ of the display device as illustrated in  FIG. 3 . 
     Referring to  FIG. 4 , the electroluminescence display panel  110  and the fingerprint sensor  140  of the display device  100  according to an embodiment of the present disclosure will be described. 
     A fingerprint sensor  140  is positioned under the rear side of the electroluminescence display panel  110  of the display device  100  according to an embodiment of the present disclosure. 
     The fingerprint sensor  140  may be used for approval function, through the display area AA by the ultrasonic wave technique, for the user. The fingerprint sensor  140  may generate ultrasonic waves and the generated ultrasonic waves may be transmitted toward the electroluminescence display panel  110 . The fingerprint sensor  140  may be configured to detect the ultrasonic waves transmitted through the electroluminescence display panel  110 , reflected by the finger, and then received by the fingerprint sensor  140  through the electroluminescence display panel  110 . The fingerprint sensor  140  may be configured to analyze a sensed ultrasonic signal to generate an ultrasonic image to determine a fingerprint. 
     The characteristics of ultrasonic waves for fingerprint recognition used in the fingerprint sensor  140  of the display device  100  according to an embodiment of the present disclosure will be described. 
     In the case of ultrasonic waves, as the frequency increases, the degree of signal attenuation increases rapidly in low-density materials. Therefore, as the frequency increases, the density of the transmission and reception channel of the ultrasonic wave greatly affects the quality of the ultrasonic signal. To improve the quality of the ultrasonic signal, in one embodiment, the Young&#39;s modulus of the corresponding mediums between a user&#39;s finger and the fingerprint sensor  140  within the transmission and reception channel have matching acoustic impedance characteristics. When an ultrasonic signal is emitted toward stacked mediums with matching acoustic impedances, there is less ultrasonic signal reflection at the interface of different mediums compared to when the stacked mediums have mismatched acoustic impedances. That is, when the ultrasonic waves enter from one medium into another medium and the acoustic impedances between the two mediums match, a reflectance of the ultrasonic waves at a boundary between the mediums is reduced. Accordingly, a transmittance of the ultrasonic waves to a next medium is increased. 
     In the case of an ultrasonic image for fingerprint recognition, the resolution of the ultrasonic image increases as the frequency increases. Ultrasonic fingerprint recognition technology requires a level of ultrasonic image resolution that can detect the fingerprint valley. 
     The fingerprint sensor  140  disposed under the rear surface of the electroluminescence display panel  110  of the display device  100  according to an embodiment of the present disclosure may be configured to receive and transmit a frequency of at least 10 MHz or more to recognize a fingerprint. According to the above-described configuration, the fingerprint can be recognized by using the electroluminescence display panel  110  as a channel for ultrasonic transmission and reception. 
     The fingerprint sensor  140  disposed under the rear surface of the electroluminescence display panel  110  of the display device  100  according to an embodiment of the present disclosure may be configured to receive and transmit a frequency of 15 MHz or less to recognize a fingerprint. If a frequency of 15 MHz or more is used, the level of ultrasonic wave signal attenuation can be significant, and signal sensitivity may be reduced when the electroluminescence display panel is used as a transmission and reception channel. 
       FIG. 5  is a cross-sectional view illustrating a stack structure of an exemplary electroluminescence display panel which can be applied to a cross-section A′-A″ of a display device schematically illustrated in  FIG. 4 . 
     Referring to  FIG. 5 , an electroluminescence display panel  110  according to an embodiment of the present disclosure will be described. The electroluminescence display panel  110  as illustrated in  FIG. 5  is merely an example, and various modifications with respect to the stacking structure, stacking order, thickness, and density of each element of the electroluminescence display panel  110  may be made without departing from the technical scope of the present disclosure. 
     The display device  100  according to an embodiment of the present disclosure may be configured to include an electroluminescence display panel  110  and a fingerprint sensor  140  under the rear side of the electroluminescence display panel  110 . 
     The fingerprint sensor  140  may generate ultrasonic waves. The ultrasonic waves generated by the fingerprint sensor  140  may pass through the electroluminescence display panel  110  and may detect the density difference of the air portion within the fingerprint valley and the skin of the fingerprint. As an example, the fingerprint sensor  140  may be configured to include a sensor substrate  142 , transmitting (Tx) electrodes  141  and receiving (Rx) electrodes  143  on the sensor substrate  142 , a Tx/Rx layer  144  on the Rx electrodes  141  and Rx electrodes  143 , and a cover substrate  146  on the Tx/Rx layer  144 . However, the present disclosure is not limited thereto. 
     Generally, the fingerprint sensor  140  obtains an image of a fingerprint by measuring the difference in density between fingerprint ridges (skin) and fingerprint valleys (air). Specifically, the Tx electrodes  141  may be configured to output ultrasonic waves to a finger, and the Rx electrodes  143  may be configured to sense ultrasonic waves reflected to the from the finger. Accordingly, the fingerprint sensor  140  may be defined as an electrode structure configured to transmit and receive ultrasonic waves. An advantage of using ultrasonic technology to measure a fingerprint is the ability to penetrate through thicker layers of glass and transparent plastic as well as image through metal and opaque glass or plastic layers. Other advantages of using ultrasonic technology include higher resolution (in the range of 500-2000 PPI), the potential for scanning the internal structure of a finger (e.g., capillaries) which would make it extremely difficult to spoof, being able to determine heart rate, and an improved ability to cope with sweaty and dirty fingers. 
     The above-described functions of the fingerprint sensor  140  may be implemented by a control unit. That is, the control unit of the fingerprint sensor  140  can recognize a fingerprint of a user by processing ultrasonic waves transmitted and received from the Tx electrodes  141  and the Rx electrodes  143 . 
     The electroluminescence display panel  110  may be configured to include at least the substrate  112 , the transistor TFT, the electroluminescence element  122 , and the encapsulation unit ( 128 ,  130 ,  132 ). 
     The substrate  112  may be made of rigid glass. The substrate  112  supports various elements of the electroluminescence display panel  110 . On the substrate  112 , a transistor TFT is disposed. The transistor TFT as illustrated in  FIG. 5  as an example may correspond to the structure of the switching transistor and the driving transistor of the pixel PXL, which is exemplarily described. 
     The transistor TFT may be configured to include a semiconductor layer A, a first insulating layer  114  configured to insulate the semiconductor layer A from a gate electrode G, the gate electrode G configured to overlap with the semiconductor layer A on the first insulating layer  114 , a second insulating layer  116  configured to insulate the gate electrode G, the source electrode S and the drain electrode D, and a source electrode S and a drain electrode D configured to be electrically connected to the semiconductor layer A through the contact hole on the second insulating layer  116 . The above-described transistor TFT structure may be referred to as a transistor of a co-planar structure. 
     The first insulating layer  114  and the second insulating layer  116  may be formed of an inorganic insulating material such as silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON). 
     However, the transistor according to the embodiments of the present disclosure is not limited thereto and may be implemented by transistors having various structures. For example, the transistor may be configured as an inverted staggered structure. 
     The third insulating layer  118  may be formed on the transistor TFT to flatten the upper portion of the transistor TFT. The anode  120  and the transistor TFT may be electrically connected to each other through the contact hole CNT formed in the third insulating layer  118 . The third insulating layer  118  may be made of an organic material having a planarizing property for planarization. For example, photo-acrylic or polyimide may be used as the organic material. 
     An electroluminescence element  122  is disposed on the anode  120  and a cathode  126  is disposed on the electroluminescence element  122 . 
     The anode  120  may be connected to a transistor TFT to receive current. The anode  120  is electrically connected to the drain electrode D of the transistor TFT through a contact hole passing through the third insulating layer  118 . The electroluminescence element  122  is disposed on the anode  120  surrounded by a bank  124 . A spacer may be disposed on some portions of the bank  124 . The spacer may be formed in such a way that the height of a portion of the bank  124  is made higher through a halftone exposure technique. 
     The electroluminescence element  122  may be disposed in the light emitting region of the pixel. The electroluminescence element  122  may have a single-layered structure or a multi-layered structure. For example, the electroluminescence element  122  may further include a hole-transporting layer, an electron-transporting layer, and the like. The electroluminescence element  122  may include a light emitting material corresponding to a particular color of a pixel to display the particular color of each pixel. 
     In the case of an organic light emitting diode, the electroluminescence element  122  may be formed of an organic material. 
     In the case of an inorganic light emitting diode, the electroluminescence element  122  may be made of an inorganic material. For example, when an inorganic light-emitting diode is formed using a quantum-dot material, it may be referred to as a quantum-dot light emitting diode. 
     The electroluminescence elements  122  may be formed individually according to the intrinsic color of each pixel. However, the present disclosure is not limited thereto, and when all the pixels have a white color, the electroluminescence layer may be formed as a common layer. The common layer may refer to a layer formed in all areas of the display area AA. 
     The hole-transporting layer and/or the electron-transporting layer may provide a function of facilitating the movement of holes and electrons in the electroluminescence layer. The hole-transporting layer and/or the electron-transporting layer may be formed as a common layer. However, the present disclosure is not limited thereto, and the hole-transporting layer and/or the electron-transporting layer may be selectively applied to improve the characteristics of each pixel. In such case, the hole-transporting layer and/or the electron-transporting layer may be formed in a particular region of the display area AA. In addition, it is possible to have different thicknesses of the electroluminescence layer depending on the pixel. 
     The cathode  126  is formed to face the anode  120  with the electroluminescence element  122  therebetween. When the cathode  126  is formed in such a manner as to cover the display area AA, the cathode  126  may be referred to as a common electrode. 
     The encapsulation unit ( 128 ,  130 ,  132 ) may be configured to suppress moisture or oxygen from penetrating into the electroluminescence element  122 , which may be vulnerable to moisture or oxygen. The encapsulation unit ( 128 ,  130 ,  132 ) may be formed to protect the electroluminescence element  122  in particular, since the electroluminescence element  122  may be particularly vulnerable to moisture and oxygen when the electroluminescence element  122  includes an organic material. For this purpose, the encapsulation unit ( 128 ,  130 ,  132 ) may include at least a first inorganic encapsulation layer  128 , an organic encapsulation layer  130  on the first inorganic encapsulation layer  128  and a second inorganic encapsulation layer  132  on the organic encapsulation layer  130 . That is, the encapsulation unit ( 128 ,  130 ,  132 ) may be configured to include at least two inorganic encapsulation layers  128  and  132  and at least one organic encapsulation layer  130 . 
     The encapsulation unit ( 128 ,  130 ,  132 ) of the electroluminescence display panel  110  according to an embodiment of the present disclosure may be described as a structure in which the organic encapsulation layer  130  is sealed between the first inorganic encapsulation layer  128  and the second inorganic encapsulation layer  132 . 
     The first inorganic encapsulation layer  128  may be disposed on the cathode  126 . The first inorganic encapsulation layer  128  may be configured to seal a plurality of pixels arranged in the display area AA. The first inorganic encapsulation layer  128  may extend to at least a portion of the non-display area NA. The first inorganic encapsulation layer  128  may be formed of an inorganic insulating material capable of low temperature deposition technique such as silicon nitride (SiNx), silicon oxide (SiOx), silicon oxynitride (SiON), or aluminum oxide (Al 2 O 3 ). Accordingly, since the first inorganic encapsulation layer  128  is deposited in a low-temperature atmosphere, it is possible to minimize the electroluminescence element  122 , which is vulnerable to a high-temperature atmosphere, from being damaged during the deposition process of the first inorganic encapsulation layer  128 . For example, when the first inorganic encapsulation layer  128  is formed of silicon nitride, the thickness of the first inorganic encapsulation layer  128  can be set to 0.1 μm to 1.5 μm. However, the present disclosure is not limited thereto. In other words, the Young&#39;s modulus of silicon nitride, which is an exemplary inorganic material, can be approximately 100 GPa to 300 GPa. The Young&#39;s modulus of the silicon oxide, which is an exemplary inorganic material, can be approximately 70 GPa to 100 GPa. However, the present disclosure is not limited thereto. Since the encapsulation layer made of a silicone substance may have an excellent Young&#39;s modulus value, it has characteristics suitable for ultrasonic transmission and reception. 
     The organic encapsulation layer  130  serves as a buffer for relieving the stress between the respective layers of the electroluminescence display panel  110 , enhances the planarization performance, and compensates for foreign matter. Therefore, the flatness and quality of the second inorganic encapsulation layer  141  can be improved. The organic encapsulation layer  130  may be formed of an organic insulating material such as acrylic resin, epoxy resin, polyimide, polyethylene, or silicon oxycarbon (SiOC). The organic encapsulation layer  130  may be formed by a chemical vapor deposition method, an inkjet printing method, or a squeegee method. Further, the organic encapsulation layer  130  can be formed by easily adjusting the thickness. Therefore, the thickness of the encapsulation unit ( 128 ,  130 ,  132 ) can be easily controlled by adjusting the thickness of the organic encapsulation layer  130 . In addition, for convenience of explanation, the thickness of the organic encapsulation layer  130  of the electroluminescence display panel  110  according to an embodiment of the present disclosure will be described with reference to the center region of the electroluminescence element  122 . 
     The second inorganic encapsulation layer  132  may be configured to seal the organic encapsulation layer  130 . The second inorganic encapsulation layer  132 , may cover the organic encapsulation layer  130 , may be configured to contact the first inorganic encapsulation layer  128  to prevent the organic encapsulation layer  130  from being exposed to the outside. In particular, when the side surface of the organic encapsulation layer  130  is exposed to the outside, the organic encapsulation layer  130  may become a moisture and oxygen permeation path for moisture and oxygen, thus, the organic encapsulation layer  130  may be sealed by the first inorganic encapsulation layer  128  and the second inorganic encapsulation layer  132 . Accordingly, the first inorganic encapsulation layer  128  and the second inorganic encapsulation layer  132  may be configured to extend further outward than the edge of the organic encapsulation layer  130 . Therefore, the organic encapsulation layer  130  can be sealed, and the first inorganic encapsulation layer  128  and the second inorganic encapsulation layer  132  can be configured to contact each other in the non-display area NA. Particularly, when the first inorganic encapsulation layer  128  and the second inorganic encapsulation layer  132  are configured to seal each other to seal the organic encapsulation layer  130 , moisture and oxygen permeable to the organic encapsulation layer  130  can be effectively protected. The second inorganic encapsulation layer  132  may be formed of an inorganic insulating material capable of low temperature deposition technique such as silicon nitride (SiNx), silicon oxide (SiOx), silicon oxynitride (SiON), or aluminum oxide (Al 2 O 3 ). For example, when the second inorganic encapsulation layer  132  is formed of silicon nitride, the thickness of the second inorganic encapsulation layer  132  can be set to 0.1 μm to 1.5 μm. However, the present disclosure is not limited thereto. 
     The fingerprint sensor  140  of the display device  100  according to an embodiment of the present disclosure may be arranged under the rear side of the electroluminescence display panel  110 . In more detail, the fingerprint sensor  140  according to an embodiment of the present disclosure may be attached to the rear side of the substrate  112  of the electroluminescence display panel  110 . 
     A display device  100  according to an embodiment of the present disclosure includes a substrate  112 , a transistor (TFT) on the substrate  112 , an electroluminescence element  122  on the transistor TFT, an encapsulation unit ( 128 ,  130 ,  132 ) on the electroluminescence element  122  and an ultrasonic fingerprint sensor  140  under the rear side of the substrate  112 , wherein the substrate  112 , the transistor TFT, the electroluminescence element  122 , and the encapsulation unit ( 128 ,  130 ,  132 ) corresponding to the fingerprint sensor  140  may serve as a channel for ultrasonic transmission and reception of the fingerprint sensor  140 . 
     The first adhesive member μ may be configured to attach the fingerprint sensor  140  and the electroluminescence display panel  110 . For example, when the fingerprint sensor  140  and the electroluminescence display panel  110  are disposed close to each other without the first adhesive member  150 , a gap or a space may be formed between the fingerprint sensor  140  and the electroluminescence display panel  110 . Such a space can significantly affect the ultrasonic signal attenuation in the high frequency band for fingerprint recognition. Therefore, it is preferable that any gap should not be formed. 
     An area, corresponding to a substrate  112 , a transistor TFT, an electroluminescence element  122  and an encapsulation unit ( 128 ,  130 ,  132 ), serving as a transmission and reception channel of the fingerprint sensor  140  of the display device  100  according to an embodiment of the present disclosure may be configured as a gas-free, a gap-free, and a space-less so as to eliminate the cause of obstructing the transmission and reception of ultrasonic waves. 
     The display device  100  according to an embodiment of the present disclosure may be configured such that there is no space or gap between the fingerprint sensor  140  and the electroluminescence display panel  110  by the first adhesive member  150 . Therefore, it is possible to minimize deterioration of the transmission and reception sensitivity between the fingerprint sensor  140  and the electroluminescence display panel  110 . The first adhesive member  150  may be configured to adhere the fingerprint sensor  140  to the substrate  112  and may be configured to have a particular thickness and a particular Young&#39;s modulus value suitable for ultrasonic transmission and reception. 
     As the density or the Young&#39;s modulus of the first adhesive member  150  increases, the ultrasonic transmission and reception sensitivity can be improved. In addition, as the thickness of the first adhesive member  150  becomes thinner, the ultrasonic transmission and reception sensitivity can be improved. The first adhesive member  150  may be applied to a region where the fingerprint sensor  140  and the substrate  112  are overlapped with each other. That is, the first adhesive member  150  may be applied to correspond to the area of the fingerprint sensor  140 . 
     The first adhesive member  150  according to an embodiment of the present disclosure may be made of a curable adhesive material. That is, the first adhesive member  150  may be made of a resin that is defoamed and cured by a curable adhesive material. As the curable adhesive material, for example, materials such as acrylic, epoxy, and the like can be used. However, the present disclosure is not limited thereto. In other words, the Young&#39;s modulus of the epoxy, which is an exemplary adhesive member, can be approximately 2 GPa to 4 GPa. However, the present disclosure is not limited thereto. In the case of epoxy, since the Young&#39;s modulus is a relatively high material, the ultrasonic signal level may not be practically attenuated in ultrasonic transmission. 
     The thickness of the first adhesive member  150  of the display device  100  according to an embodiment of the present disclosure may be 5 μm to 15 μm. According to the thickness described above, it is possible to reduce the occurrence of bubbles or a foam while minimizing deterioration of the ultrasonic transmission/reception characteristics, and to provide a sufficient adhesive force. However, the present disclosure is not limited thereto. In other words, the adhesive member  150  may be a resin having a property of being defoamed, and the air bubbles may be removed in a cured state, so that the ultrasonic transmission/reception quality may not be reduced. 
     The color of the first adhesive member  150  according to an embodiment of the present disclosure may be transparent or opaque. In other words, in the case of ultrasonic waves, fingerprints can be recognized irrespective of the light transmittance of the first adhesive member  150 . 
     The first adhesive member  150  according to an embodiment of the present disclosure may be configured not to include a substance having a low density (e.g., low Young&#39;s modulus) such as bubbles or gas. For example, if the first adhesive member is a foam tape, since the foam tape contains a plurality of bubbles, the ultrasonic transmission and reception sensitivity can be rapidly lowered. Therefore, difficulties in fingerprint recognition may arise. 
     In other words, the first adhesive member  150  may be a resin that removes air bubbles, which may interfere with the transmission and reception of ultrasonic waves, or does not contain air bubbles. 
     According to the first adhesive member  150  according to the embodiment of the present disclosure as described above, the gap between the fingerprint sensor  140  and the electroluminescence display panel  110  can be removed and the fingerprint sensor  140  and the electroluminescence display panel  110  can be adhered, thereby facilitating the ultrasonic transmission and reception. 
     On the other hand, if one or both of the rear side of the substrate  112  and the surface of the fingerprint sensor  140  that are in contact with each other are implemented or treated with a material having sufficient self-adhesive force, and then the first adhesive member  150  may not be required. In this case, the ultrasonic transmission and reception may be further improved. 
     Hereinafter, the electroluminescence display panel  110  will be described in terms of the ultrasonic transmission and reception channel of the fingerprint sensor  140 . 
     The electroluminescence display panel  110  according to an embodiment of the present disclosure is designed in consideration of ultrasonic transmission and reception. 
     The electroluminescence display panel  110  according to an embodiment of the present disclosure may include a flexible substrate  112 , having a thickness of 3 μm to 30 μm, configured to transmit ultrasonic waves in a fingerprint recognition area FDA, a transistor TFT, on the flexible substrate  112 , configured to transmit ultrasonic waves in the fingerprint recognition area FDA, an electroluminescence element  122 , on the transistor TFT, configured to transmit ultrasonic waves in the fingerprint recognition area FDA, a first inorganic encapsulation layer  128 , on the electroluminescence element  122 , configured to transmit ultrasonic waves in the fingerprint recognition area FDA, an organic encapsulation layer  130 , on the first inorganic encapsulation layer  128 , having a thickness of 3 μm to 10 μm, configured to transmit ultrasonic waves in a fingerprint recognition area FDA, and a second inorganic encapsulation layer  132 , on the organic encapsulation layer  130 , configured to transmit ultrasonic waves in the fingerprint recognition area FDA. 
     The transmission and reception channel of the fingerprint sensor  140  of the display device  100  according to an embodiment of the present disclosure may be configured such that ultrasonic waves output from the fingerprint sensor  140  are reflected by a fingerprint of a user&#39;s finger. 
     For example, the substrate  112  may be formed of glass. As the glass substrate has high density or high Young&#39;s modulus value, it can be advantageous for ultrasonic transmission and reception. Further, since the rigidity is excellent even when the fingerprint sensor  140  is attached to the substrate  112 , the deformation of the substrate  112  can be minimized. 
     For example, a portion of the insulating layers of the electroluminescence display panel  110  may be made of an inorganic material. The inorganic material is relatively high in Young&#39;s modulus compared to the organic material and can be relatively thin in thickness compared to the organic material. Thus, the inorganic material may affect less influence to the ultrasonic transmission and reception than the organic material. 
     For example, a part of the insulating layer and a part of the encapsulation unit of the electroluminescence display panel  110  may be made of an organic material. The organic material has a relatively low Young&#39;s modulus as compared to an inorganic material. In addition, the organic material may have a planarizing property and may have a relatively thicker thickness than the inorganic material. In addition, the organic material can easily control its thickness. Thus, the organic material may have a greater effect on signal sensitivity to ultrasonic transmission and reception than the inorganic material. Accordingly, it is possible to control the sensitivity of the ultrasonic signal of the fingerprint sensor  140  by adjusting the thickness of the insulating layers made of the organic material. 
     The thickness of the organic encapsulation layer  130  of the encapsulation unit ( 128 ,  130 ,  132 ) of the electroluminescence display panel  110  according to an embodiment of the present disclosure may be 3 μm to 10 μm. According to the thickness described above, at the same time, the organic encapsulation layer  130 , may compensate the foreign matter of the first inorganic encapsulation layer  128 , may planarize the second inorganic encapsulation layer  132 , and may perform as a transmission and reception channel of the ultrasonic wave for fingerprint recognition. 
     A display device  100  (i.e., an apparatus) according to an embodiment of the present disclosure may include an electroluminescence display panel  110  including a substrate  112 , a transistor TFT positioned on the substrate  112 , an electroluminescence element  122  positioned on the transistor TFT, an encapsulation unit ( 128 ,  130 ,  132 ) positioned on the electroluminescence element  122 , and a fingerprint sensor  140 , positioned under the rear side of the electroluminescence display panel  110 , configured to output a signal having a frequency from 10 MHz to 15 MHz, wherein the encapsulation unit ( 128 ,  130 ,  132 ) may include a first inorganic encapsulation layer  128  adjacent to the electroluminescence element  122 , an organic encapsulation layer  130  on the first inorganic encapsulation layer  128 , and the second inorganic encapsulation layer  132  on the organic encapsulation layer  130 , and wherein the thickness of the organic encapsulation layer  130  may be between 3 μm to 10 μm. Thus, the Tx electrodes  141  of the fingerprint sensor  140  may generate a suitable frequency of an ultrasonic wave to pass through the all elements such as the transistor TFT, the electroluminescence element  122 , and the encapsulation unit ( 128 ,  130 ,  132 ) of the electroluminescence display panel  110  and the Rx electrodes  143  may receive the reflected ultrasonic wave by the sensor electrode  144 . 
     In addition, the encapsulation unit ( 128 ,  130 ,  132 ) may be configured to include at least two inorganic encapsulation layers having a Young&#39;s modulus from 70 GPa to 300 GPa. 
     The fingerprint sensor  140  of the display apparatus  100  according to an embodiment of the present disclosure can detect a user&#39;s fingerprint that is in contact with the electroluminescence display panel  110  using a frequency of 10 MHz or more, for example, a frequency of 10 MHz to 15 MHz, and recognize the shape of the fingerprint by recognizing the difference in reflection characteristics of the space (e.g., air) in the valley between the skin portions of the fingerprint. In one embodiment, the fingerprint sensor  140  may transmit a signal that has a frequency that can travel through air (e.g., less than 10 MHz) while still providing high resolution of a user&#39;s fingerprint. 
     In one embodiment, the fingerprint sensor  140  may operate in a fingerprint sensing mode and a proximity sensor mode. In the fingerprint sensing mode, the fingerprint sensor  140  outputs a signal at a frequency (e.g., 10 Mhz to 15 Mhz) for recognizing the shape of the fingerprint. In the proximity sensor mode, the fingerprint sensor  140  outputs a signal at a frequency that is less than the frequency of the fingerprint sensor mode. In the proximity sensor mode, the fingerprint sensor  140  may be used to determine whether the display device is next to a person&#39;s face. 
     In addition, a conventional electroluminescence display panel having a glass substrate generally implemented a frit-seal structure in which a glass portion is melted in a non-display area to form a sealed portion by sealing a non-display region. The conventional frit-seal structure has a simple process and excellent moisture permeability. However, since the frit-seal structure is filled with nitrogen gas above the cathode, there is a problem that the ultrasonic wave for fingerprint recognition is absorbed. Therefore, the embodiments of the present disclosure with the fingerprint sensor  140  may implement a sealing structure such as a face-seal structure, which is suitable for the fingerprint detection. However, the conventional frit-seal structure is not suitable for the fingerprint detection. 
     The encapsulation unit ( 128 ,  130 ,  132 ) of the electroluminescence display panel  110  according to an embodiment of the present disclosure is configured not to include any gap or any gas layer along the ultrasonic transmission and reception channel region. That is, between the fingerprint sensor  140  and the electroluminescence display panel  110 , there should not be any objects or any space that can attenuate the ultrasonic signal. 
     According to the above-described configuration, the display device  100  according to an embodiment of the present disclosure may provide a fingerprint sensor  140 , an electroluminescence display panel  110  capable of providing a transmission and reception channel or path of the fingerprint sensor  140  while displaying an image by emitting a plurality of pixels PXL, and a first adhesive member  150  for attaching the electroluminescence display panel  110  and the fingerprint sensor  140 , thereby recognizing the fingerprint in a fingerprint recognition area where an image is displayed. 
       FIG. 6  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to another embodiment of the present disclosure. 
     Redundant features of the display device  200  according to another embodiment of the present disclosure and the display device  100  according to an embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     Hereinafter, specific elements of the electroluminescence display panel  110  may be described with reference to  FIG. 5 , if necessary. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , and the first adhesive member  150  of the display device  200  according to another embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , and the first adhesive member  150  of the display device  100  according to an embodiment of the present disclosure. Thus, the redundant descriptions with respect to the electroluminescence display panel  110 , the fingerprint sensor  140 , and the first adhesive member  150  may be omitted merely for convenience of explanation. 
     The electroluminescence display panel  110  of the display device  200  according to another embodiment of the present disclosure may be configured to include a flexible substrate  112 , having a thickness of 3 μm to 30 μm, configured to transmit ultrasonic waves in a fingerprint recognition area FDA, a transistor TFT, on the flexible substrate  112 , configured to transmit ultrasonic waves in the fingerprint recognition area FDA, an electroluminescence element  122 , on the transistor TFT, configured to transmit ultrasonic waves in the fingerprint recognition area FDA, a first inorganic encapsulation layer  128 , on the electroluminescence element  122 , configured to transmit ultrasonic waves in the fingerprint recognition area FDA, an organic encapsulation layer  130 , on the first inorganic encapsulation layer  128 , having a thickness of 3 μm to 10 μm, configured to transmit ultrasonic waves in a fingerprint recognition area FDA, and a second inorganic encapsulation layer  132 , on the organic encapsulation layer  130 , configured to transmit ultrasonic waves in the fingerprint recognition area FDA. The substrate of the electroluminescence display panel  110  of the display device  200  according to another embodiment of the present disclosure may be formed of a material having a flexibility characteristic. For example, the material of the substrate having flexibility properties may be a polymer resin such as polyethersulphone, polyacrylate, polyetherimide, polyethylene-napthalate, polyethylene-terephthalate (PET), polyphenylene-sulfide, polyallylate, polyimide (PI), polycarbonate, photoacrylic, cellulose-acetate-propionate (CAP) or the like. The flexible substrate  112  may be configured to absorb visible light. 
     If the substrate of the electroluminescence display panel  110  is a flexible substrate other than glass, for example, in the case of a substrate formed of a polyimide material, the density and/or the Young&#39;s modulus may be relatively lower than that of glass. 
     The substrate of the electroluminescence display panel  110  of the display device  200  according to another embodiment of the present disclosure may be made of a flexible material. In other words, the exemplary flexible substrate may be composed of polyimide, and in this case, the Young&#39;s modulus of the flexible substrate may be approximately 1.5 GPa to 3 GPa. For example, when the substrate is made of polyimide, the thickness may be 3 μm to 30 μm. However, the present disclosure is not limited thereto. Since the substrate made of polyimide has excellent Young&#39;s modulus, it may have suitable characteristics for ultrasonic transmission and reception. 
     If the thickness of the flexible substrate is 30 μm or more, the flexibility of the electroluminescence display panel  110  can be reduced. If the thickness of the substrate is less than 3 μm, it may be difficult for the substrate to sufficiently support the elements disposed on the electroluminescence display panel  110 . 
     The inventors of the present disclosure have formed the substrate of the electroluminescence display panel  110  as a flexible material and directly bonded to the substrate with the first adhesive member  150 . As a result, it has been observed by the inventors of the present disclosure that the display area of the display device where the fingerprint sensor  140  is attached is deformed unevenly due to the stress exerted during the curing of the first adhesive member  150 , so that the image quality was reduced. 
     Thus, the display device  200  according to another embodiment of the present disclosure further includes a support substrate  160  and a second adhesive member  152  disposed between the electroluminescence display panel  110  and the first adhesive member  150 . In such case, the substrate  112  of the electroluminescence display panel  110  may be configured to have a flexible characteristic. 
     The support substrate  160  is disposed between the fingerprint sensor  140  and the electroluminescence display panel  110  including the flexible substrate so that the flatness of the electroluminescence display panel  110  can be improved from being deformed by the stress of the first adhesive member  150 . 
     That is, the support substrate  160  may be disposed between the electroluminescence display panel  110  and the fingerprint sensor  140  to support the fingerprint sensor  140  and the electroluminescence display panel  110 . The first adhesive member  150  may be disposed between the support substrate  160  and the electroluminescence display panel  110  to bond the supporting substrate  160  to the electroluminescence display panel  110 . 
     In addition, it is not desirable that there is an empty space in the ultrasonic transmission and reception path or channel of the fingerprint sensor  140 , and therefore, an adhesive member capable of filling any empty space is required. However, the first adhesive member may cause stress due to its adhesiveness. Therefore, the stress caused by the first adhesive member  150  needs to be reduced. 
     The support substrate  160  of the display device  200  according to another embodiment of the present disclosure may be adhered to the electroluminescence display panel  110  by the second adhesive member  152 . Further, the fingerprint sensor  140  may be adhered to the support substrate  160 . The support substrate  160  may be configured to support a display area AA of the electroluminescence display panel  110  and a non-display area NA surrounding the periphery of the display area AA. 
     The support substrate  160  may be made of, for example, polyethylene-terephthalate (PET). In other words, the Young&#39;s modulus of the exemplary support substrate  160  may be approximately 2.5 GPa to 3.5 GPa. However, the present disclosure is not limited thereto. For example, when the support substrate  160  is made of polyethylene-terephthalate, the thickness may be 50 μm to 150 μm. However, the present disclosure is not limited thereto. The support substrate made of polyethylene-terephthalate has characteristics suitable for ultrasonic transmission and reception because of its excellent Young&#39;s modulus value. 
     Further, the control unit of the fingerprint sensor  140  may be configured to transmit ultrasonic waves having a proper frequency to pass through the electroluminescence display panel  110  and the support substrate  160  under the back side of the electroluminescence display panel  110 , for example, ultrasonic waves having a frequency of 10 MHz to 15 MHz can be generated and transmitted and then received through the Tx electrodes  141  and the Rx electrodes  143 . 
     According to another embodiment of the present disclosure, the support substrate  160 , in the region where the fingerprint sensor  140  is attached, of the display device  200  can suppress the deformation of the flatness of the electroluminescence display panel  110  due to the stress exerted by the curing of the adhesive member  150 . The support substrate  160  may be placed under the rear surface of the flexible substrate  112 , which is configured to transmit ultrasonic waves in the fingerprint recognition area FDA. A fingerprint sensor  140  configured to generate ultrasonic waves in the fingerprint recognition area FDA may be placed under the rear surface of the supporting substrate  160 . 
     The support substrate  160  may have a transparent or opaque characteristic. The support substrate  160  may be configured to absorb visible light. 
     When the support substrate  160  is transparent, it is convenient to perform a vision inspection to inspect various defects such as bubbles generated when the support substrate  160  is attached to the electroluminescence display panel  110  during the fabrication process, signal wiring defects of the electroluminescence display panel  110 , or the like defects. In addition, if any bubbles are present, ultrasonic transmission and reception degradation may occur. 
     Even if the support substrate  160  is opaque, the visible light transmittance of the support substrate  160  does not have a particular influence on the ultrasonic transmission and reception. For example, the visible light absorption rate of the supporting substrate  160  may be 80% or more. 
     The second adhesive member  152  may be, for example, a pressure-sensitive adhesive (PAS). In other words, the Young&#39;s modulus of the exemplary pressure-sensitive adhesive member may be approximately 0.02 MPa to 0.4 MPa. However, the present disclosure is not limited thereto. 
     When the second adhesive member  152  is a pressure-sensitive adhesive having a Young&#39;s modulus value relatively lower than the other elements, the performance of the ultrasonic transmission and reception channel may be deteriorated as the thickness of the second adhesive member  152  increases. 
     The thickness of the second adhesive member  152  of the display device  200  according to another embodiment of the present disclosure may be 5 μm to 15 μm. According to the thickness described above, it is possible to provide a sufficient adhesive force while reducing the occurrence of bubbles while minimizing deterioration of the ultrasonic transmission and reception characteristics. However, the present disclosure is not limited thereto. 
     According to the above-described configuration, the display device  200  according to another embodiment of the present disclosure can reduce the deformation of the display device  200  by the support substrate  160  even if the fingerprint sensor  140  is attached by the first adhesive member  150 . Therefore, the appearance and image quality of the display device  200  can be improved. In addition, the thickness of the second adhesive member  152  can be adjusted to remedy deformation of the substrate of the electroluminescence display panel  110  while minimizing deterioration in signal sensitivity with respect to the ultrasonic transmission and reception channel. 
       FIG. 7  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  300  according to the other embodiment of the present disclosure and the display device  200  according to another embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , and the second adhesive member  152  of the display device  300  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , and the second adhesive member  152  of the display device  200  according to another embodiment of the present disclosure. Thus, the redundant descriptions with respect to the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , and the second adhesive member  152  may be omitted merely for convenience of explanation. 
     The first adhesive member  150 - 1  of the display device  300  according to the other embodiment of the present disclosure may be configured to correspond to the support substrate  160 . 
     For example, the first adhesive member  150 - 1  may be configured to cover the rear surface of the support substrate  160 , or may have a specific area corresponding to the support substrate  160 . 
     For example, the first adhesive member  150 - 1  may be configured to overlap at least the display area AA of the electroluminescence display panel  110 . That is, the first adhesive member  150 - 1  may be configured to cover the display area AA of the electroluminescence display panel  110 . 
     For example, the first adhesive member  150 - 1  may be configured to overlap at least the display area AA and the non-display area NA of the electroluminescence display panel  110 . 
     For example, the second adhesive member  152  may be disposed on the front surface of the supporting substrate  160 , and the first adhesive member  150 - 1  may be disposed under the rear surface of the supporting substrate  160 . 
     For example, the first adhesive member  150 - 1  and the second adhesive member  152  may be made of the same material. 
     The adhesive member  150 - 1  may be configured to have a predetermined thickness in consideration of transmission characteristics of ultrasonic frequency for fingerprint recognition. 
     The first adhesive member  150 - 1  may be composed of a pressure-sensitive adhesive. In other words, the Young&#39;s modulus of the exemplary pressure-sensitive adhesive member may be approximately 0.02 MPa to 0.4 MPa. At this time, the thickness of the first adhesive member  150 - 1  may be 5 μm to 15 μm. However, the present disclosure is not limited thereto. 
     According to the above-described configuration, the first adhesive member  150 - 1  can provide sufficient adhesion force to support the fingerprint sensor  140  and the supporting substrate  160  while minimizing degradation of ultrasonic transmission and reception characteristics. Unlike the first adhesive member  150  according to an embodiment of the present disclosure, the first adhesive member  150 - 1  according to the other embodiment of the present disclosure may be formed as a film-type adhesive on the supporting substrate  160  and then adhered to the fingerprint sensor  140 . In this case, since the first adhesive member  150 - 1  may not require additional curing process, the stress may be reduced as compared to the first adhesive member  150  according to an embodiment of the present disclosure. Therefore, deformation of the flatness of the electroluminescence display panel  110  can be relatively reduced by the first adhesive member  150 - 1  than that of the first adhesive member  150 . 
     In addition, since the first adhesive member  150 - 1  can be provided in other areas other than the fingerprint sensor  140 , elements other than the fingerprint sensor  140  can be adhered. In addition, a plurality of fingerprint sensors  140  may be attached at various positions. 
       FIG. 8  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  400  according to the other embodiment of the present disclosure and the display device  200  according to another embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , and the second adhesive member  152  of the display device  400  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , and the second adhesive member  152  of the display device  200  according to another embodiment of the present disclosure. Thus, the redundant descriptions with respect to the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , and the second adhesive member  152  may be omitted merely for convenience of explanation. 
     The inventors of the present disclosure have bonded the fingerprint sensor  140  to the electroluminescence display panel  110  with the first adhesive member  150 . When the fingerprint sensor  140  is attached to the electroluminescence display panel  110  and exposed to external light for a certain time or more, the degree of external light exposure of the TFT corresponding to the fingerprint recognition area FDA of the electroluminescence display panel  110  may be different from the area other than the fingerprint recognition area FDA. Further, it has been observed that due to the difference, defects may occur, for example, shadow-mura, in which the transistor TFT characteristics of the pixel PXL may be changed in the region where the fingerprint sensor  140  is attached. 
     Thus, the display device  400  according to the other embodiment of the present disclosure may be configured to include the light-shield member  162  disposed between the supporting substrate  160  and the fingerprint sensor  140 . 
     The display device  400  according to the other embodiment of the present disclosure may include an electroluminescence display panel  110  including a fingerprint detection area (fingerprint recognition area), a display area AA configured to display an image and a non-display area NA around the display area AA, a support substrate  160  configured to support the electroluminescence display panel  110 , a fingerprint sensor  140  under the rear surface of the support substrate  160 , and a light-shield member  162 , under the support substrate  160 , configured to light-shield the fingerprint sensor  140 . 
     A display device  400  according to the other embodiment of the present disclosure may include an electroluminescence display panel  110  including a plurality of pixels PXL, a support substrate  160  adhered to a rear side of the electroluminescence display panel  110 , a light-shield member  162  under at least a portion of a rear side of the support substrate  160 , and a fingerprint sensor  140  attached to the rear side of the light-shield member  162  by a first adhesive member  150 . 
     A display device  400  according to the other embodiment of the present disclosure may include an electroluminescence display panel  110  including a plurality of pixels PXL on a flexible substrate and an encapsulation unit covering the plurality of pixels PXL, a transparent support substrate  160  under a rear surface of the electroluminescence display panel  110 , a light-shield member  162  at a certain area of a rear surface of the transparent support substrate  160 , a cushion member  168 , including an opening corresponding to the certain area, under the rear surface of the transparent support substrate  160 , and a ultrasonic fingerprint sensor  140  attached to the light-shield member  162  at the opening. 
     The light-shield member  162  may suppress the occurrence of shadow-mura due to the attachment of the fingerprint sensor  140 . The light-shield member  162  can minimize the deterioration of the signal sensitivity of the ultrasonic transmission and reception channel of the fingerprint sensor  140 . Thus, the control unit of the fingerprint sensor  140  may generate ultrasonic waves of a suitable frequency to pass through the light-shield member  162  disposed under the rear surface of the electroluminescence display panel  110 . For example, 10 MHz to 15 MHz signal may be generated, and then the Tx electrodes  141  and Rx electrodes  143  may transmit and receive the ultrasonic waves. 
     The light-shield member  162  may be configured to shield at least the area where the fingerprint sensor  140  and the electroluminescence display panel  110  overlap. However, the present disclosure is not limited thereto, and the light-shield member  162  may be configured to shield all of the display area AA. Further, the light-shield member  162  may be configured to shield the display area AA and the non-display area NA. 
     The light-shield member  162  may be made of a material having a material having at least 80% of a visible light absorption rate. However, the present disclosure is not limited thereto. As an example, if the display device including the electroluminescence display panel  110  is used in an automobile interior or in an environment with a large influence of visible light, such as a kiosk in a public place, and then it may be suitably applied by adjusting the area, thickness, absorption rate, and the like of the light-shield member  162 . 
     For example, the light-shield member  162  may include a visible light absorbing dye or a polyethylene-terephthalate having a black color. The light-shield member  162  may be configured to include at least one of graphite, carbon, and graphene. 
     The light-shield member  162  may be coated directly to the rear side of the support substrate  160  or may be bonded together by a separate bonding member. When the light-shield member  162  is made of polyethylene-terephthalate, the thickness of the light-shield member  162  may be made thinner than the thickness of the support substrate  160 . That is, since the light-shield member  162  shields the fingerprint sensor  140  from the electroluminescence display panel  110 , the thickness of the support substrate  160  for providing the flatness of the electroluminescence display panel  110  can be relatively thinner. However, the present disclosure is not limited thereto. For example, the thickness of the light-shield member  162  including polyethylene terephthalate may be 10 μm to 25 μm. 
     For example, the light-shield member  162  may be made of a light absorbing ink. The light-shield member  162  may be coated directly under the rear surface of the support substrate  160 . When the light-shield member  162  is a light absorbing ink, the thickness of the light-shield member  162  may be made thinner than the thickness of the support substrate  160 . For example, the thickness of the light-shield member  162  including the light absorbing ink may be 8 μm to 20 μm. According to the above-described configuration, even if the fingerprint sensor  140  is attached by the light-shield member  162 , the occurrence of shadow-mura in the electroluminescence display panel  110  can be suppressed and the deterioration of signal sensitivity of the ultrasonic transmission and reception channel can be minimized. In addition, the flatness of the electroluminescence display panel  110  can be improved by the light-shield member  162 . In addition, the thickness of the light-shield member  162  may be 8 μm to 25 μm. 
     The thickness of the light-shield member  162  may be thinner than the thickness of the support substrate  160  and the thickness of the light-shield member  162  may be made thinner than the thickness of the cushion member  168 . 
       FIG. 9  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  500  according to the other embodiment of the present disclosure and the display device  300  according to the other embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1  and the second adhesive member  152  of the display device  500  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1  and the second adhesive member  152  of the display device  300  according to the other embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The features of the light-shield member  162  of the display device  500  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the light-shield member  162  of the display device  400  according to the other embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The display device  500  according to the other embodiment of the present disclosure may be configured to include the light-shield member  162  disposed between the support substrate  160  and the fingerprint sensor  140 . 
     According to the above-described configuration, even if the fingerprint sensor  140  is attached to the light-shield member  162 , the occurrence of shadow-mura in the electroluminescence display panel  110  can be suppressed and the deterioration of signal sensitivity of the ultrasonic transmission and reception channel can be minimized. In addition, the flatness of the electroluminescence display panel  110  can be improved by the light-shield member  162 . 
     According to the above-described configuration, the first adhesive member  150 - 1  can minimize the deterioration of the ultrasonic transmission and reception characteristics, and the first adhesive member  150 - 1  can be further provided to the area other than the attachment area of the fingerprint sensor  140 , thereby some components other than the fingerprint sensor  140  may be attached by the first adhesive member  150 - 1 . 
       FIG. 10  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  600  according to the other embodiment of the present disclosure and the display device  400  according to the other embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , and the light-shield member  162  of the display device  600  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , and the light-shield member  162  of the display device  400  according to the other embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The inventors of the present disclosure have found that when the fingerprint sensor  140  is disposed under the rear side of the electroluminescence display panel  110 , the heat dissipation characteristic of the rear side of the electroluminescence display panel  110  may be varied by the arrangement of the fingerprint sensor  140 . In addition, it is also observed that a residual image may be generated on the displayed image due to the temperature deviation of the electroluminescence display panel  110  according to the heat radiation deviation. 
     Accordingly, the display device  600  according to the other embodiment of the present disclosure may be configured to include the heat dissipation member  164  disposed under the rear surface of the light-shield member  162 . 
     The heat dissipation member  164  may be configured to surround the fingerprint sensor  140  and overlap a portion of the display area AA to perform the function of a heat sink for the electroluminescence display panel  110 . For example, the heat dissipation member  164  may be configured to substantially cover the display area AA excluding the opening OP. 
     In addition, an adhesive member may be further included between the heat dissipation member  164  and the light-shield member  162 . However, it should be noted that since the adhesive member corresponding to the region other than the ultrasonic transmission and reception channel of the fingerprint sensor  140  does not substantially affect the performance of the ultrasonic transmission and reception channel. Therefore, the region other than the ultrasonic transmission and reception channel of the fingerprint sensor  140  may be omitted for convenience of explanation. 
     In addition, the heat dissipation member  164  may be configured to have an opening OP corresponding to the fingerprint sensor  140 . The opening OP may have gaps GAP 1  and GAP 2  spaced apart from the fingerprint sensor  140  by a particular distance. According to the above-described configuration, the heat dissipation member  164  can be separated from the first adhesive member  150  regardless of the thickness or the step the first adhesive member  150 . Therefore, delamination or peel-off of the heat dissipation member  164  due to the level of the first adhesive member  150  may be suppressed. 
     The heat dissipation member  164  may be made of a material having a high thermal conductivity. For example, the heat dissipation member  164  may be made of a material such as metal, graphite, and/or graphene. For example, the thickness of the heat dissipation member  164  may be 50 μm to 100 μm. However, the present disclosure is not limited thereto. 
     According to the above-described configuration, the temperature deviation between the fingerprint sensor  140  and periphery of the fingerprint sensor  140  can be reduced by the heat dissipation member  164 . Therefore, it is possible to reduce the occurrence of image retention due to the attachment of the fingerprint sensor  140 . 
     In addition, when the heat dissipation member  164  is a conductive material, the heat dissipation member  164  can be electrically grounded. However, the present disclosure is not limited thereto. 
     On the other hand, the heat dissipation member  164 - 1  may not be bonded as a separate element. By improving a particular component, such as a layer, a structure and/or its material to improve its heat dissipation function, thereby substituting the heat dissipation member. In such case, the light-shield member  162  may substitute the heat dissipation member. 
       FIG. 11  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  700  according to the other embodiment of the present disclosure and the display device  600  according to the other embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , and the light-shield member  162  of the display device  700  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , and the light-shield member  162  of the display device  600  according to the other embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The heat dissipation member  164 - 1  of the display device  700  according to the other embodiment of the present disclosure may be implemented substantially the same material as the heat dissipation member  164  of the display device  600  according to the other embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The display device  700  according to the other embodiment of the present disclosure may be configured to include the heat dissipation member  164 - 1  below the rear side of the light-shield member  162 . The heat dissipation member  164 - 1  may be configured to cover the fingerprint sensor  140 . That is, the heat dissipation member  164 - 1  may be configured to overlap with the fingerprint sensor  140 . 
     For example, the heat dissipation member  164 - 1  may be configured to adhere to the light-shield member  162  while surrounding the fingerprint sensor  140 . 
     For example, the heat dissipation member  164 - 1  may be configured to package the fingerprint sensor  140 . Further, the heat dissipation member  164 - 1  may be attached only to the rear side of the fingerprint sensor  140  without contacting the light-shield member  162 . 
     According to the above-described configuration, the heat dissipation member  164 - 1  can heat sink the heat generated from the electroluminescence display panel  110  and the fingerprint sensor  140 . According to the above-described configuration, the temperature deviation around the fingerprint sensor  140  and the fingerprint sensor  140  can be reduced by the dissipation member  164 - 1 . Therefore, it is possible to reduce the occurrence of a residual image due to a temperature deviation due to the attachment of the fingerprint sensor  140 . The position, thickness, area, material, and the like of the heat dissipation member  164 - 1  may be variously modified according to the type, size, use environment, purpose of use, and the like of the display device including the fingerprint sensor  140 . 
       FIG. 12  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  800  according to the other embodiment of the present disclosure and the display device  600  according to the other embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , the light-shield member  162 , the heat dissipation member  164  of the display device  800  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , the light-shield member  162 , the heat dissipation member  164  of the display device  600  according to the other embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The inventors of the present disclosure have observed that when the fingerprint sensor  140  is disposed under the rear surface of the electroluminescence display panel  110 , the electroluminescence display panel  110  and the fingerprint sensor  140  may be damaged by an external impact due to an arrangement of the fingerprint sensor  140 . 
     In addition, the fingerprint sensor  140  may be constituted by a substrate having a high Young&#39;s modulus value for transmitting ultrasonic waves for fingerprint transmission, for example, ultrasonic waves having a frequency of 10 MHz or more. Therefore, the fingerprint sensor  140  may be damaged by an external impact. 
     The display device  800  according to the other embodiment of the present disclosure may be configured to include a cushion member  168  disposed under the rear surface of the heat dissipation member  164 . The cushion member  168  of the present disclosure may refer to a member configured to absorb an impact. For example, the cushion member  168  may be a material having a high elasticity or having a deformable property to absorb a shock and having an excellent restoration ability. 
     The cushion member  168 , surrounds the fingerprint sensor  140 , may be configured to overlap with at least a portion of the display area AA to absorb a shock transmitted to the electroluminescence display panel  110  and the fingerprint sensor  140 . For example, the cushion member  168  may be configured to cover the entire display area AA except for the opening OP. The cushion member  168  may absorb the impact that may be transmitted through the electroluminescence display panel  110 , thereby protecting the ultrasonic fingerprint sensor  140 . The cushion member  168  may be made of a light absorbing material. Therefore, the shadow-mura may be be reduced by the cushion member  168  as well. 
     The cushion member  168  may be configured not to be disposed between the fingerprint sensor  140  and the electroluminescence display panel  110  if the ultrasonic wave, dedicated for fingerprint recognition, having at least 10 MHz of frequency. Ultrasonic waves can be absorbed if the cushion member  168  is disposed in the middle of the ultrasonic transmission and reception channel. 
     In addition, an adhesive member may be further included between the cushion member  168  and the heat dissipation member  164 . However, it should be noted that since the adhesive member corresponding to the region other than the ultrasonic transmission and reception channel of the fingerprint sensor  140  does not substantially affect the performance of the ultrasonic transmission and reception channel. Therefore, the region other than the ultrasonic transmission and reception channel of the fingerprint sensor  140  may be omitted for convenience of explanation. 
     In addition, the cushion member  168  may be configured to have an opening corresponding to the fingerprint sensor  140 . The opening may have gaps spaced a certain distance from the fingerprint sensor  140 . Since the opening and the gaps are illustrated in  FIG. 10 , a redundant description will be omitted for convenience of explanation. According to the above-described configuration, the cushion member  168  can be separated from the first adhesive member  150  regardless of the step of the first adhesive member  150 . Therefore, peeling of the cushion member  168  due to the step of the first adhesive member  150  can be suppressed. 
     In addition, the light-shield member  162  may be configured to shield the opening of the cushion member  168  to shield the rear side of the electroluminescence display panel  110  from light. 
     The cushion member  168  may be made of an impact-absorbing material. For example, the cushion member  168  may be made of a material such as foam tape and/or rubber. For example, the thickness of the cushion member  168  may be 60 μm to 200 μm. However, the present disclosure is not limited thereto. 
     For example, according to the above-described configuration, when the cushion member  168  is a foam tape, even if an impact is transmitted to the electroluminescence display panel  110 , it is possible to reduce the impact transmitted from the display panel  110  to the fingerprint sensor  140  by the cushion member  168 . Therefore, when the electroluminescence display panel  110  is shocked, the fingerprint sensor  140  may be protected from being damaged. 
     In addition, when the cushion member  168  is a foam tape, the foam tape can absorb ultrasonic waves for fingerprint recognition because it contains a plurality of bubbles. Therefore, it is possible to absorb the unnecessary transmission of the ultrasonic wave to the area other than the fingerprint recognition area FDA of the electroluminescence display panel  110 . Therefore, unnecessary ultrasonic noise can be reduced. However, the present disclosure is not limited thereto. Therefore, the cushion member  168  according to the embodiments of the present disclosure may be referred to as an ultrasonic absorbing member for fingerprint recognition. 
     The cushion member  168  may be positioned under the rear side of the support substrate  160  and surround the fingerprint sensor  140 . A portion of the outer periphery of the light-shield member  162  may be overlapped with the cushion member  168 . 
     In some cases, the cushion member  168  and the heat dissipation member  164  may be embodied as one member rather than separate members. That is, the present disclosure can be realized as a material that can integrate a cushion function and a heat dissipation function together with a single film or layer type member. Such an integrated functional member 
     The position, thickness, area, material, and the like of such an integrated functional member may be variously modified according to the type, size, use environment, purpose of use, and the like of the display device including the fingerprint sensor  140 . 
       FIG. 13  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  900  according to the other embodiment of the present disclosure and the display devices ( 500 ,  800 ) according to the embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1 , the second adhesive member  152 , and the light-shield member  162  of the display device  900  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1 , the second adhesive member  152 , and the light-shield member  162  of the display device  500  according to the other embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The cushion member  168  of the display device  900  according to the other embodiment of the present disclosure may be implemented substantially the same material as the cushion member  168  of the display device  800  according to the other embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The display device  900  according to the other embodiment of the present disclosure may be configured to include the heat dissipation member  164 - 1  under the rear surface of the cushion member  168 . The heat dissipation member  164 - 1  may be configured to cover the fingerprint sensor  140 . That is, the heat dissipation member  164 - 1  may be configured to overlap with the fingerprint sensor  140 . 
     For example, the heat dissipation member  164 - 1  may be configured to be in direct contact with the cushion member  168  and the fingerprint sensor  140 . 
     According to the above-described configuration, the heat dissipation member  164 - 1  may transfer heat generated in the fingerprint sensor  140 . Further, a system circuitry connected to the electroluminescence display panel  110  may be further disposed under the rear surface of the heat dissipation member  164 - 1 . Further, a frame for supporting the electroluminescence display panel  110  and the system circuitry may be further disposed between the electroluminescence display panel  110  and the system circuitry. In this case, the heat dissipation member  164 - 1  can transfer heat of the fingerprint sensor  140  toward the frame. According to the above-described configuration, the temperature deviation around the fingerprint sensor  140  and the fingerprint sensor  140  can be reduced by the heat dissipation member  164 - 1 . Therefore, it is possible to reduce the occurrence of a residual image due to a temperature deviation due to the attachment of the fingerprint sensor  140 . 
     In addition, the level difference between the fingerprint sensor  140  and the heat dissipation member  164 - 1  can be reduced by the cushion member  168 . According to the above-described configuration, as compared with the heat dissipation member  164 - 1  of the display device  700  according to the other embodiment of the present disclosure, the possibility of generating a tension that can be generated by the heat dissipation member  164 - 1  can be reduced. 
     In addition, when the heat dissipation member  164 - 1  of the display device  700  according to the other embodiment of the present disclosure is adhered, a pressure may be applied to the fingerprint sensor  140  due to a misalign error in the adhesion process. In such case, the fingerprint sensor  140  may apply unwanted pressure to the electroluminescence display panel  110 . Accordingly, the flatness of the electroluminescence display panel  110  may be lowered, and the pressed mark may be visually recognized. 
     However, when the step between the fingerprint sensor  140  and the heat dissipation member  164 - 2  is minimized by the cushion member  168 , the pressure that can be applied to the fingerprint sensor  140  when adhering the heat dissipation member  164 - 2  can be minimized. Therefore, occurrence of a flatness defect of the electroluminescence display panel  110  can be reduced. 
       FIG. 14  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  1000  according to the other embodiment of the present disclosure and the display device  200  according to another embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , and the second adhesive member  152 , of the display device  1000  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , and the second adhesive member  152  of the display device  200  according to another embodiment of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The inventors of the present disclosure have recognized that the electromagnetic interference (EMI) generated by the scan pulse and the data signal of the electroluminescence display panel  110  may become a noise to the fingerprint sensor  140 . Further, the inventors of the present disclosure have recognized that electromagnetic interference generated by the operation of the fingerprint sensor  140  may become a noise of the electroluminescence display panel  110 . 
     Particularly, the ultrasonic fingerprint sensors may require a high voltage to generate a high frequency of ultrasonic wave. Accordingly, electromagnetic interference can be generated. However, the present disclosure is not limited to the driving voltage level of the fingerprint sensor  140 . 
     Accordingly, the electroluminescence display panel  110  may be deteriorated in image quality due to the electromagnetic interference of the fingerprint sensor  140 , but also, at the same time, the fingerprint sensor  140  may be deteriorated in fingerprint recognition sensitivity due to the electromagnetic interference of the electroluminescence display panel  110 . 
     Thus, the display device  1000  according to the other embodiment of the present disclosure may be configured to include the EMI shield member  170  disposed between the support substrate  160  and the fingerprint sensor  140 . 
     A display device  1000  according to the other embodiment of the present disclosure may include a substrate, a display area including a plurality of pixels on the substrate and having a fingerprint recognition area FDA, a support substrate  160  under the rear surface of the substrate, a fingerprint sensor  140  under the rear surface of the support substrate  160  in accordance with the fingerprint recognition area FDA, and an EMI shield member  170  disposed between the support substrate  160  and the fingerprint sensor  140 . 
     A display device  1000  according to the other embodiment of the present disclosure may include an electroluminescence display panel  110  including a plurality of pixels PXL on a flexible substrate, a support substrate  160  supporting the electroluminescence display panel  110 , and a EMI shield member  170  under a rear surface of the support substrate  160  configured to transmit an ultrasonic wave of a particular frequency. 
     A display device  1000  according to the other embodiment of the present disclosure may include a substrate on which a plurality of pixels PXL are arranged thereon, a see-through support substrate  160  under a rear surface of the substrate, a cushion member  168 , including an opening, under a rear surface of the see-through support substrate  160 , an ultrasonic fingerprint sensor  140  at the opening, and an EMI shield member, overlaps with the opening, configured to shield an electromagnetic interference noise through the see-through support substrate  160  that may affect the ultrasonic fingerprint sensor  140 . 
     A display device  1000  according to the other embodiment of the present disclosure may include an electroluminescence display panel  110 , a fingerprint sensor  140  under a rear surface of the electroluminescence display panel  110 , and an EMI shield member  170  that is a part of an ultrasonic transmission and reception channel of the fingerprint sensor  140 , configured to shield a plurality of electrical signals generated in the electroluminescence display panel  110 , thereby improving the image quality of the electroluminescence display panel  110 . 
     The EMI shield member  170  may be configured to shield at least a region where the fingerprint sensor  140  and the electroluminescence display panel  110  are overlapped. For example, the EMI shield member  170  may be configured to shield at least the fingerprint recognition area FDA. However, the present disclosure is not limited thereto. Further, the EMI shield member  170  may be configured to shield the fingerprint recognition area FDA and at least a portion of the display area AA. Furthermore, the EMI shield member  170  may be configured to shield the display area AA and the non-display area NA. That is, the EMI shield member  170  may be configured to shield at least the electromagnetic interference noise between the electroluminescence display panel  110  and the fingerprint sensor  140  by shielding at least the fingerprint recognition area FDA. 
     The fingerprint sensor  140  may be fixed to the rear side of the EMI shield member  170  and output ultrasonic waves of a specific frequency toward the EMI shield member  170 . The control unit of the fingerprint sensor  140  may generate an ultrasonic wave having a specific frequency band such as 10 MHz to 15 MHz to allow the ultrasonic wave to pass through the EMI shield member  170  disposed under the rear side of the electroluminescence display panel  110  such that the ultrasonic wave can be transmitted and received through the Tx electrodes  141  and the Rx electrodes  143 . 
     The EMI shield member  170  may be made of a conductive material. For example, the EMI shield member  170  may comprise metallic particles or may be a metal foil. The EMI shield member  170  may be coated directly at the rear side of the support substrate  160  or may be bonded together through a separate bonding member. When the EMI shield member  170  is a conductive ink, the thickness of the EMI shield member  170  may be 300 nm or less. For example, the thickness of the EMI shield member  170  may be between 25 nm and 300 nm. The EMI shield member  170  may be a metal layer and may be configured to shield external light transmitted through the electroluminescence display panel  110 . 
     The inventors of the present disclosure have also recognized that as the thickness of the EMI shield member  170  becomes thicker than 300 nm, the shielding performance of the electromagnetic interference noise may be reduced. It has also been recognized that when the thickness of the EMI shield member  170  is thinner than 25 nm, the shielding performance of the electromagnetic interference performance may be reduced. 
     Accordingly, the EMI shield member  170  of the display device  100  according to the other embodiment of the present disclosure may be configured to include copper (Cu), and the thickness may be 150 nm to 250 nm. However, the present disclosure is not limited thereto. 
     For example, the EMI shield member  170  may be a conductive ink. The EMI shield member  170  may be coated or printed directly under the rear side of the support substrate  160 . 
     For example, the EMI shield member  170  may be a thin metal film. The EMI shield member  170  may be deposited on the support substrate  160 . 
     For example, when the EMI shield member  170  is formed directly on the support substrate  160 , since an adhesive member is unnecessary, an additional adhesive member may not be required even if the EMI shield member  170  is added. Therefore, it is possible to improve the image quality of the electroluminescence display panel  110  and the fingerprint recognition sensitivity of the fingerprint sensor  140  while maintaining the signal sensitivity of the fingerprint sensor  140 . 
     For example, the electroluminescence display panel  110  may be configured to include a fingerprint recognition area FDA corresponding to a fingerprint sensor  140  and an EMI shield member  170 , overlapping with the fingerprint recognition area FDA, having an area larger than an area of the fingerprint sensor  140 . 
     In addition, the EMI shield member  170  may be grounded. When the EMI shield member  170  is electrically grounded, the shielding performance can be improved. In addition, when the EMI shield member  170  is grounded, the transistor TFT of the electroluminescence display panel  110  and the EMI shield member  170  may generate parasitic capacitance. Therefore, in order to minimize the parasitic capacitance of the EMI shield member  170 , the distance between the EMI shield member  170  and the electroluminescence display panel  110  may be at least 20 μm. Specifically, the distance between the EMI shield member  170  and the TFT of the electroluminescence display panel  110  may be at least 20 μm. Therefore, even if the EMI shield member  170  is included in the display device  1000 , the parasitic capacitance problem can be minimized. 
     According to the above-described configuration, as the increase in thickness can be minimized, electromagnetic interference noise generated between the fingerprint sensor  140  and the electroluminescence display panel  110  can be shielded by the EMI shield member  170 , thereby the fingerprint sensing performance of the fingerprint sensor  140  and the image quality of the electroluminescence display panel  110  can be improved at the same time. 
     Alternatively, the EMI shield member  170  may be integrated into another element, for example, a support substrate  160 , to provide a shielding ability rather than being implemented as a separate component. 
     Whether to implement the EMI shield member  170  as a separate element, as an integrated element with other element or both can be variously modified according to the type, size, use environment, purpose of use, and the like of the display device including the fingerprint sensor  140 . 
       FIG. 15  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  1100  according to the other embodiment of the present disclosure and the display devices ( 300 ,  1000 ) according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1 , and the second adhesive member  152 , of the display device  1100  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1 , and the second adhesive member  152  of the display devices ( 300 ,  1000 ) according to the other embodiments of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The display device  1100  according to the other embodiment of the present disclosure may be configured to include the EMI shield member  170  disposed between the support substrate  160  and the first adhesive member  150 - 1 . 
     The EMI shield member  170  may be configured to shield at least the area where the fingerprint sensor  140  and the electroluminescence display panel  110  overlap. For example, the EMI shield member  170  may be configured to shield at least the fingerprint recognition area FDA. However, the present disclosure is not limited thereto, and the EMI shield member  170  may be configured to shield at least a part of the fingerprint recognition area FDA and the display area AA. Further, the EMI shield member  170  may be configured to shield the display area AA and the non-display area NA. 
     According to the above-described configuration, the electromagnetic interference noise generated between the fingerprint sensor  140  and the electroluminescence display panel  110  may be shielded by the EMI shield member  170 . Accordingly, the fingerprint sensing performance of the fingerprint sensor  140  and the image quality of the electroluminescence display panel  110  can be improved at the same time. 
     In addition, since the first adhesive member  150 - 1  can be provided in other areas except for the fingerprint sensor  140 , components other than the fingerprint sensor  140  can be adhered by the first adhesive member  150 - 1 . 
     In some cases, a metallic material may be included in the first adhesive member  150 - 1  to substitute the EMI shield member  170  or to provide an additional shielding ability to the first adhesive member  150 - 1 . That is, the EMI shield member may be variously modified according to the type, size, use environment, purpose of use, and the like of the display device including the fingerprint sensor  140 . 
       FIG. 16  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  1200  according to the other embodiment of the present disclosure and the display devices ( 400 ,  1000 ) according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , and the light-shield member  162 , and the EMI shield member  170  of the display device  1100  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , and the light-shield member  162 , and the EMI shield member  170  of the display devices ( 400 ,  1000 ) according to the other embodiments of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The inventors of the present disclosure have recognized that when the EMI shield member  170  is a metallic material, it may have a reflection characteristic with respect to visible light, and when the external light is reflected by the EMI shield member having a reflection characteristic, the image quality of the electroluminescence display panel  110  may be deteriorated. 
     The display device  1200  according to the other embodiment of the present disclosure may include the light-shield member  162  and the EMI shield member  170  which are sequentially stacked between the support substrate  160  and the fingerprint sensor  140 . That is, EM the shield member  170  is positioned under the rear surface of the light-shield member  162 . 
     In addition, if the light-shield member  162  is positioned under the rear surface of the EMI shield member  170 , electromagnetic interference noise may be reduced, but it may be difficult to improve the external light reflection problem as described-above. 
     According to the above-described configuration, the problem of deterioration in image quality due to external light due to the EMI shield member  170  can be suppressed by disposing the light-shield member  162  between the EMI shield member  170  and the electroluminescence display panel  110 . That is, the light-shield member  162  can absorb at least a portion of the external light. At the same time, the electromagnetic interference noise generated between the fingerprint sensor  140  and the electroluminescence display panel  110  can be shielded by the EMI shield member  170 . Accordingly, the fingerprint sensing performance of the fingerprint sensor  140  and the image quality of the electroluminescence display panel  110  can be improved at the same time. 
     Herein, the light-shield member  162  and the EMI shield member  170  are described as separate elements but it may be realized as a single film or layer that integrate a light-shielding function and an EMI shielding function together. That is, the integrated shield member may be variously modified according to the type, size, use environment, purpose of use, and the like of the display device including the fingerprint sensor  140 . 
       FIG. 17  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  1300  according to the other embodiment of the present disclosure and the display devices ( 500 ,  1000 ) according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1 , the second adhesive member  152 , the light-shield member  162 , and the EMI shield member  170  of the display device  1100  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1 , the second adhesive member  152 , the light-shield member  162 , and the EMI shield member  170  of the display devices ( 500 ,  1000 ) according to the other embodiments of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The display device  1300  according to the other embodiment of the present disclosure may be configured to include the light-shield member  162  and the EMI shield member  170  which are sequentially stacked between the support substrate  160  and the fingerprint sensor  140 . That is, the EMI shield member  170  is under the rear surface of the light-shield member  162 . 
     The image quality degradation due to the external light due to the EMI shield member  170  can be suppressed by the light-shield member  162  disposed between the EMI shield member  170  and the electroluminescence display panel  110 . At the same time, the electromagnetic interference noise generated between the fingerprint sensor  140  and the electroluminescence display panel  110  is shielded by the EMI shield member  170 , thereby improving the fingerprint sensing performance of the fingerprint sensor  140  and the image quality of the electroluminescence display panel  110  at the same time. 
     In addition, since the first adhesive member  150 - 1  can be provided in other areas except for the fingerprint sensor  140 , components other than the fingerprint sensor  140  also can be adhered. 
       FIG. 18  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  1400  according to the other embodiment of the present disclosure and the display devices ( 800 ,  1200 ) according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , the light-shield member  162 , the cushion member  168 , and the EMI shield member  170  of the display device  1400  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 , the second adhesive member  152 , the light-shield member  162 , the cushion member  168 , and the EMI shield member  170  of the display devices ( 800 ,  1200 ) according to the other embodiments of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The inventors of the present disclosure have recognized that when the cushion member  168  is configured to surround the fingerprint sensor  140  and the third adhesive member  154 , arranged between the cushion member  168  and the EMI shield member  170 , configured to surround the fingerprint sensor  140  may not affect in the ultrasonic transmission and reception channel of the fingerprint sensor  140 . Thus, it is recognized that the ultrasonic transmission characteristics may be ignored. That is, the third adhesive member  154 , which can be disposed in an area other than the ultrasonic transmission and reception channel of the fingerprint sensor  140 , does not substantially affect the ultrasonic transmission and reception channel. Therefore, the Young&#39;s modulus value and the thickness of the third adhesive member  154  may not be limited. 
     Accordingly, the display device  1400  according to the other embodiment of the present disclosure may be configured to include the third adhesive member  154  disposed between the cushion member  168  and the EMI shield member  170 . 
     According to the above-described configuration, the problem of deterioration in image quality due to external light due to the EMI shield member  170  can be suppressed by the light-shield member  162  disposed between the EMI shield member  170  and the electroluminescence display panel  110 . Further, unnecessary dispersion of ultrasonic waves from the fingerprint sensor  140  can be absorbed by the cushion member  168 . Further, the electromagnetic interference noise generated between the fingerprint sensor  140  and the electroluminescence display panel  110  can be shielded by the EMI shield member  170 . Furthermore, the Young&#39;s modulus and the thickness of the third adhesive member  154  may not be limited thereto. 
     In some cases, the cushion member  168  and the EMI shield member  170  may be realized as an integrated member. That is, the integrated member may be realized as a single film or layer that integrates a cushion function and an EMI shielding function together. That is, the position, thickness, area, material, and the like of the integrated member may be variously modified according to the type, size, use environment, purpose of use, and the like of the display device including the fingerprint sensor  140 . 
       FIG. 19  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  1500  according to the other embodiment of the present disclosure and the display devices ( 800 ,  1300 ) according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1 , the second adhesive member  152 , the light-shield member  162 , the cushion member  168 , and the EMI shield member  170  of the display device  1500  according to the other embodiment of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member  150 - 1 , the second adhesive member  152 , the light-shield member  162 , the cushion member  168 , and the EMI shield member  170  of the display devices ( 800 ,  1300 ) according to the other embodiments of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     A display device  1500  according to the other embodiment of the present disclosure may include a light-shield member  162 , an EMI shield member  170 , a first adhesive member  150 - 1  and a cushion member  168  configured to surround the fingerprint sensor  140 . 
     According to the above-described configuration, the problem of deterioration in image quality due to external light due to the EMI shield member  170  can be suppressed by the light-shield member  162  disposed between the EMI shield member  170  and the electroluminescence display panel  110 . Further, unnecessary transmission of ultrasonic waves from the fingerprint sensor  140  can be reduced by the cushion member  168  and electromagnetic interference between the fingerprint sensor  140  and the electroluminescence display panel  110  can be shielded by the EMI shield member  170 . Since the first adhesive member  150 - 1  can be provided in a periphery area of the fingerprint sensor  140 , components other than the fingerprint sensor  140  can be adhered. 
       FIG. 20  and  FIG. 21  are cross-sectional views schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiments of the present disclosure. 
     Redundant features of the display devices ( 1600 ,  1700 ) according to the other embodiments of the present disclosure and the display devices ( 700 ,  800 ,  900 ,  1400 ) according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member ( 150 ,  150 - 1 ), the second adhesive member  152 , the light-shield member  162 , the heat dissipation member ( 164 ,  164 - 1 ), the cushion member  168 , and the EMI shield member  170  of the display devices ( 1600 ,  1700 ) according to the other embodiments of the present disclosure may be implemented substantially the same as the features of the electroluminescence display panel  110 , the fingerprint sensor  140 , the support substrate  160 , the first adhesive member ( 150 ,  150 - 1 ), the second adhesive member  152 , the light-shield member  162 , the heat dissipation member ( 164 ,  164 - 1 ), the cushion member  168 , and the EMI shield member  170  of the display devices ( 800 ,  1300 ) according to the other embodiments of the present disclosure. Thus, the redundant descriptions may be omitted merely for convenience of explanation. 
     The display device  1600  according to the other embodiment of the present disclosure is characterized in that the heat dissipation member  164  is disposed under the rear side of the cushion member  168 . 
     The display device  1700  according to the other embodiment of the present disclosure, the cushion member  168 - 1  is configured to cover the display area and the fingerprint sensor  140 , and the heat dissipation member  164 - 1  is configured to correspond to the cushion member  168 - 1  under the rear surface of the cushion member  168 - 1 . 
     According to the above-described configuration, a generation of shadow-mura problem can be suppressed, an electromagnetic interference noise can be shielded, an impact applied to the fingerprint sensor  140  can be absorbed, and an unnecessary transmission of ultrasonic waves from the fingerprint sensor  140  can be reduced. 
     In addition, the ultrasonic waves output from the fingerprint sensor  140  can be transmitted toward to the rear side of the fingerprint sensor. Referring to  FIG. 21 , when the cushion member  168 - 1  is configured to cover the rear side of the fingerprint sensor  140 , a portion of the ultrasonic wave transmitted toward a frame disposed under the rear surface of the fingerprint sensor  140  for supporting a system circuitry and an electroluminescence display panel  110  can be absorbed by the cushion member  168 - 1 . Therefore, unnecessary transmission of the ultrasonic waves of the fingerprint sensor  140  toward the rear side can be reduced. 
     In some embodiments, the cushion member may be separated into a plurality of pieces, and a cushion member composed of a plurality of pieces may be configured to surround the fingerprint sensor  140 . 
     In some cases, the cushion member  168 - 1  and the heat dissipation member  164 - 1  may be realized as an integrated member. That is, the integrated member may be realized as a single film or layer that integrates a cushion function and a heat sinking function together. That is, the position, thickness, area, material, and the like of the integrated member may be variously modified according to the type, size, use environment, purpose of use, and the like of the display device including the fingerprint sensor  140 . 
       FIG. 22  to  FIG. 27  are cross-sectional views schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiments of the present disclosure. 
     Redundant features of the display devices ( 1800 ,  1900 ,  2000 ,  2100 ,  2200 ,  2300 ) according to the other embodiments of the present disclosure and the display devices as illustrated in  FIG. 1  to  FIG. 21  according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The display devices ( 1800 ,  1900 ,  2000 ,  2100 ,  2200 ,  2300 ) according to the embodiments of the present disclosure may include a light and EMI shield member  172 , for shielding external light and electromagnetic interference noise, disposed between the electroluminescence display panel  110  and the fingerprint sensor  140 . 
     The light and EMI shield member  172  may refer to a multi-functional member configured to perform the functions of the light-shield member  162  and the EMI shield member  170 . Further, the light and EMI shield member  172  may be applied as an alternative embodiment for some embodiments to which the light-shield member  162  and the EMI shield member  170  are applied. 
     According to the above-described configuration, the embodiments including the light-shield member  162  and the EMI shield member  170  may be embodied as alternative embodiments in which the light and EMI shield member  172  is substituted, thereby reducing the cost. 
     The light and EMI shield member  172  may be configured to have a light absorbing property and a conductivity at the same time. For example, the light and EMI shield member  172  may include graphite, carbon, graphene, metal particles, and the like. The light and EMI shield member  172  may have a visible light absorption rate of 80% or more and a sheet resistance of (30 Ω/Sq/mil) or less. The thickness of the light and EMI shield member  172  may be 50 nm to 300 nm. However, the present disclosure is not limited thereto. If the thickness of the light and EMI shield member  172  is 300 nm or more, the shielding performance may be deteriorated. If the thickness of the light and EMI shield member  172  is less than 50 nm, the visible light absorption rate may be lowered. 
     According to the above-described configuration, the light and EMI shield member  172  can be applied to minimize the decrease in the signal sensitivity of the ultrasonic transmission and reception channel while minimizing the thickness increase of the display device. Further, it is possible to suppress the occurrence of shadow-mura. Further, it is possible to shield the electromagnetic interference noise to improve the performance of the fingerprint sensor  140  and to minimize the deterioration of the image quality of the electroluminescence display panel  110 . 
     In addition, the fingerprint sensor  140  may be attached to the light and EMI shield member  172  by the first adhesive member  150  or the first adhesive member  150 - 1 . 
     In addition, the fingerprint sensor  140  may suppress undesired dispersion of ultrasonic waves by the cushion member  168  under the rear side of the light and EMI shield member  172 . 
     The heat dissipation member  164 , which may be included in various embodiments of the present disclosure, may be grounded. The light and EMI shield member  172  and the heat dissipation member  164 , which may be included in the various embodiments of the present disclosure, may be respectively grounded. The heat dissipation member  164 , which may be included in various embodiments of the present disclosure, may be electrically connected to the light and EMI shield member  172 . However, the present disclosure is not limited thereto, and it is possible that the EMI shield member  170  and the light-shield member  162  are electrically connected to each other. 
     According to the above-described configuration, when the heat dissipation member  164  and the light and EMI shield member  172  may be electrically connected to each other, the potential difference may not be generated between the heat dissipation member  164  and the light and EMI shield member  172  when they are grounded. Therefore, the parasitic capacitance can be reduced. In addition, unnecessary noise signals can be grounded. 
     In addition, referring to  FIG. 27 , the light and EMI shield member  172  and the heat dissipation member  164  are illustrated as being grounded, but the present disclosure is not limited thereto, and in various embodiments. For example, it is also possible that the members having shielding ability and the members having heat-sinking ability with a conductivity of the display devices ( 1600 ,  1700 ,  2300 ,  3000 ,  3100 ) can be grounded to each other. 
       FIG. 28  to  FIG. 35  are cross-sectional views schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiments of the present disclosure. 
     Redundant features of the display devices ( 2400 ,  2500 ,  2600 ,  2700 ,  2800 ,  2900 ,  3000 ,  3100 ) according to the other embodiments of the present disclosure and the display devices as illustrated in  FIG. 1  to  FIG. 27  according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The display devices ( 2400 ,  2500 ,  2600 ,  2700 ,  2800 ,  2900 ,  3000 ,  3100 ) according to the embodiments of the present disclosure may include a light-shield support substrate  174  disposed between the electroluminescence display panel  110  and the fingerprint sensor  140 . 
     The light-shield support substrate  174  refers to a support substrate having a visible light-absorbing function configured to perform the functions of the light-shielding member  162  and the support substrate  160 . The light-shield support substrate  174  may be alternatively applied to which the support substrate  160  and the light-shielding member  162  are applied. 
     The display device according to embodiments of the present disclosure may include an electroluminescence display panel  110 , a fingerprint sensor  140  disposed below the rear side of the electroluminescence display panel  110 , and a light-shield support substrate  174 , positioned between the electroluminescence display panel  110  and the fingerprint sensor  140 , configured to absorb external light that is transmitted through the electroluminescence display panel  110  and reflected by the fingerprint sensor  140 . 
     The display device according to the embodiments of the present disclosure may include an electroluminescence display panel  110  comprising a plurality of pixels formed on a flexible substrate having a Young&#39;s modulus of 2.5 GPa to 3.5 GPa, a fingerprint sensor  140  under the electroluminescence display panel  110 , and a light-shield support substrate  174 , positioned between the electroluminescence display panel  110  and the fingerprint sensor  140 , configured to absorb at least a portion external light pass through the electroluminescence display panel  110 , and configured to reduce a flatness degradation of the electroluminescence display panel  110  due to a stress exerted by an adhesive member that bonds the fingerprint sensor  140 . 
     According to the above-described configuration, alternative embodiments having the light-shield support substrate  174  may be embodied to substitute the embodiments including the support substrate  160  and the light-shielding member  162 , thereby reducing the manufacturing process and the manufacturing cost. 
     The light-shield support substrate  174  can improve the flatness of the electroluminescence display panel  110 . The light-shield support substrate  174  may be, for example, light absorbing polyethylene terephthalate (PET). In other words, the Young&#39;s modulus of the exemplary light-shield support substrate  174  may be approximately 2.5 GPa to 3.5 GPa. However, the present disclosure is not limited thereto. For example, when the light-shield support substrate  174  is polyethylene terephthalate, the thickness may be 50 μm to 200 μm. In addition, since the light-shield support substrate  174  may be configured to perform the support function and the light-shielding function simultaneously. Accordingly, the thickness of the support substrate  160  according to some embodiments may be thicker. However, the present disclosure is not limited thereto. 
     The light-shield support substrate  174  may be converted into a transparent or opaque state. That is, the light-shield support substrate  174  may include a material whose optical light-shielding property or visible light transmittance is variable under specific conditions. However, the present disclosure is not limited thereto. 
     When the transparency of the light-shield support substrate  174  can be varied, a transparent state can be utilized during the manufacturing process. 
     For example, at the time of manufacturing the electroluminescence display panel  110 , an inspection for various defects such as wiring failure of the electroluminescence display panel  110  can be processed, if the light-shield support substrate  174  is in a transparent state when the light-shield support substrate  174  is bonded to the electroluminescence display panel  110 . 
     When the transparency of the light-shield support substrate  174  can be varied, the opaque state can be utilized after the manufacturing process. 
     For example, the light-shield support substrate  174  may become opaque after the inspection is completed. Therefore, after the defect inspection, the light-shield support substrate  174  can have a light-shielding characteristic. Thus, it can function as a light-shielding member. 
     The light-shield support substrate  174  may be configured to include a temperature-reactive or photo-reactive material. 
     That is, the light-shield support substrate  174  may include a temperature-reactive material, and the light-shield support substrate  174  may be heat-treated at a predetermined threshold temperature or more to change the visible light absorption rate. For example, the thermo-chromatic material included in the light-shield support substrate  174  can vary in visible light absorption rate when heated above the predetermined threshold temperature, thereby changing the color from transparent to opaque. The light-shield support substrate  174  may have a visible light absorption rate of 80% or more. However, the present disclosure is not limited thereto. 
     For example, the photo-chromatic material included in the light-shield support substrate  174  can be turned from transparent to black when exposed to light of a particular wavelength. The light-shield support substrate  174  may have a visible light absorption rate of 80% or more. However, the present disclosure is not limited thereto. 
     According to the above-described configuration, the thickness increase of the display device can be minimized, the degradation in signal sensitivity of the ultrasonic transmission and reception channel can be minimized, the generation of shadow-mura can be suppressed, and the flatness of the electroluminescence display panel  110  can be maintained by using the light-shield support substrate  174 . 
     In addition, the fingerprint sensor  140  can suppress undesired diffusion of ultrasonic waves by the cushion member  168  disposed under the rear side of the light and EMI shield member  172 . 
       FIG. 36  is a cross-sectional view schematically illustrating a cross section A′-A″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  3200  according to the other embodiment of the present disclosure and the display devices as illustrated in  FIG. 1  to  FIG. 35  according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The display device  3200  according to the other embodiment of the present disclosure may include the light-shield support substrate  174  disposed under the rear side of the electroluminescence display panel  110  and the EMI shield member  170 - 1  disposed under the rear side of the light-shield support substrate  174 . 
     The EMI shield member  170 - 1  may be configured to shield the fingerprint sensor  140  by overlapping with the fingerprint sensor  140 . That is, the EMI shield member  170 - 1  may be configured to cover at least the fingerprint sensor  140 . The EMI shield member  170 - 1  may be configured to have a light-shield ability. 
     In addition, the heat dissipation member  164  may be arranged under the rear side of the light-shield support substrate  174  to cover the outer periphery of the EMI shield member  170 - 1 . That is, the EMI shield member  170 - 1  may be configured to overlap the opening of the cushion member  168  to shield the rear side of the electroluminescence display panel  110  corresponding to the area where the fingerprint sensor  140  is disposed. Further, the cushion member  168  may be formed of a light-shielding foam tape. Further, the rear side of the electroluminescence display panel  110  may be completely shielded, and at least the fingerprint recognition area FDA can be shielded. 
     According to the above-described configuration, the image quality degradation, for example, shadow-mura due to external light can be suppressed by the light-shielding member  162 - 1  and the cushion member  168 . 
     In other words, the cushion member  168  may be configured to cover a portion of the outer periphery of the heat dissipation member  164 . 
     According to the above-described configuration, the light-shield support substrate  174  between the EMI shield member  170 - 1  and the electroluminescence display panel  110  can suppress image quality deterioration due to external light caused by the EMI shield member  170 - 1 . For example, shadow-mura can be suppressed. In addition, heat generated from the fingerprint sensor  140  can be effectively dissipated. According to the above-described configuration, the EMI shield member  170 - 1  and the cushion member  168  can suppress the image quality degradation caused by external light. In the above-described configuration, when the EMI shield member  170 - 1  shields at least the fingerprint sensor  140 , most of the electromagnetic interference noise can be suppressed. 
       FIG. 37  is a conceptual diagram schematically illustrating a display device capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  3300  according to the other embodiment of the present disclosure and the display device  100  according to an embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     Referring to  FIG. 37 , a display device  3300  according to the other embodiment of the present disclosure will be described. 
     The display device  3300  according to the other embodiment of the present disclosure may include an electroluminescence display panel  110  and a case supporting the electroluminescence display panel  110 . 
     The display area of the electroluminescence display panel  110  of the display device  3300  can be maximized by removing the conventional speakers ( 12 ,  13 ). 
     The display device  3300  according to the other embodiment of the present disclosure may include at least one speaker capable of outputting sound through the electroluminescence display panel  110 . For example, a first speaker SPK 1  and a second speaker SPK 2  are disposed under the rear side of the electroluminescence display panel  110 . Accordingly, at least one speaker can be integrated with the electroluminescence display panel  110 . 
     The fingerprint recognition area FDA may be configured to recognize fingerprint recognition and the pressure of the user&#39;s finger. 
       FIG. 38  is a plan view schematically illustrating an electroluminescence display panel of a display device capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  3300  according to the other embodiment of the present disclosure and the display device  100  according to an embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     Referring to  FIG. 38 , an electroluminescence display panel  110  of the display device  3300  according to the other embodiment of the present disclosure will be described. 
     Ultrasonic waves generated from the fingerprint sensor can be transmitted to the fingerprint recognition area FDA set in the display area AA to enable fingerprint recognition. The degree of pressure of the user&#39;s finger can be recognized. Thus, it is also possible to distinguish the degrees of the pressure. Although only one fingerprint recognition area is illustrated in  FIG. 38 , the present disclosure is not limited thereto. In addition, a plurality of fingerprint recognition areas can be arranged. 
     For example, the two fingerprint recognition areas can be arranged symmetrically with respect to the center of the display area. According to the above-described arrangement, even if the display area AA is rotated 180 degrees, the same user experience can be provided that can perform the fingerprint recognition function at substantially the same position with respect to the user. That is, the same user experience can be provided regardless of which direction the user holds the display device. 
     In the speaker areas SPK 1  and SPK 2  set in the display area AA, the sound generated from the film-type speaker disposed under the rear side of the electroluminescence display panel  110  is transmitted to the front side of the electroluminescence display panel  110  to output sound. 
     For example, two speaker areas can be arranged symmetrically with respect to the center of the pixel area. According to the above-described configuration, even if the display area AA rotates 180 degrees, an user experience can be provided with an acoustic experience at substantially the same position. 
     For example, a plurality of speaker areas may be arranged within a display area at specific distances to output multi-channel sound. 
       FIG. 39A  is a cross-sectional view schematically illustrating a cross section B′-B″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  3300 A according to the other embodiment of the present disclosure and the display devices as illustrated in  FIG. 1  to  FIG. 36  according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The electroluminescence display panel  110  of the display device  3300 A according to the other embodiment of the present disclosure may include a substrate, configured to act as an ultrasonic transmission and reception channel of a fingerprint sensor  140 , a transistor on the substrate, an electroluminescence element on the transistor, and an encapsulation unit on the electroluminescence element. 
     The display device  3300 A according to the other embodiment of the present disclosure may include a fingerprint sensor  140  under the rear side of the electroluminescence display panel  110  and a pressure sensor  190  under the rear side of the fingerprint sensor  140 . The fingerprint sensor  140  may be configured to transmit ultrasonic waves to a fingerprint and receive the reflected ultrasonic waves to recognize fingerprints touched on the fingerprint recognition area FDA. 
     The display device  3300 A according to the other embodiment of the present disclosure may include a display area AA including a fingerprint recognition area FDA, a plurality of pixels PXL disposed on a substrate of an electroluminescence display panel  110 , an ultrasonic fingerprint sensor  140  under a rear side of the substrate corresponding to the fingerprint recognition area FDA, and a pressure sensor  190  under the rear side of the fingerprint sensor  140 . In addition, when the pressure sensor  190  is disposed under the rear side of the fingerprint sensor  140 , the user&#39;s finger pressure can be detected more accurately in the fingerprint recognition area FDA. If the pressure sensor  190  does not overlap with the fingerprint sensor  140  or overlaps at least a portion of the fingerprint sensor  140 , the pressure sensing sensitivity may be reduced during fingerprint recognition. If the pressure sensor  190  does not overlap with the fingerprint sensor  140 , at least a portion is overlapped, or pressure is applied to an area other than the fingerprint recognition area FDA, the fingerprint sensor  140  may be operated unintentionally. 
     A display device  3300 A according to the other embodiment of the present disclosure may include an electroluminescence display panel  110  configured to display an image, a fingerprint sensor  140  under the rear surface of the electroluminescence display panel  110 , and a pressure sensor  190  under the rear side of the fingerprint sensor  140  and configured to detect a pressure that can be applied to the electroluminescent display panel  110 . Further, the front surface of the fingerprint sensor  140  may be fixed to the rear surface of the electroluminescence display panel  110  by the first adhesive member  150 . Furthermore, the rear surface of the fingerprint sensor  140  may be fixed to the pressure sensor  190  by the fourth adhesive member  156 . 
     A display device  3300 A according to the other embodiment of the present disclosure may include a plurality of pixels on a flexible substrate, a cushion member, under the flexible substrate, having at least one opening, at least one pressure sensor  190 , under the cushion member  168 , configured to receive pressure through a periphery of the at least one opening, and a fingerprint sensor  140  between the flexible substrate and the at least one pressure sensor  190 . At least one pressure sensor  190  may be configured to receive at least a portion of the pressure through the corresponding at least one fingerprint sensor  140 . At least one pressure sensor  190  may be configured to receive at least another portion of the pressure through a corresponding cushion member  168 . In addition, when the pressure is transmitted only through the fingerprint sensor  140 , the stress applied to the fingerprint sensor  140  may be increased. When the pressure is transmitted only through the cushion member  168 , the pressure may be absorbed by the cushion member  168 , and the pressure sensing precision may be reduced. The pressure sensor  190  may be realized by a resistance sensing type or a capacitance sensing type. However, the present disclosure is not limited thereto. 
     The light-shield support substrate  174  may be located between the substrate of the electroluminescence display panel  110  and the ultrasonic fingerprint sensor  140 . However, as described above, it is also possible to implement using alternative configurations disclosed in the embodiments of the present disclosure. For example, the light-shield support substrate  174  may be substituted with the support substrate  160  of other embodiments. It is also possible that the light-shield member  162  is further disposed under the rear surface of the support substrate  160 . 
     The cushion member  168  may be disposed under the rear side of the light-shield support substrate  174  and may be configured to surround the fingerprint sensor  140  with an opening formed therein. The thickness of the cushion member  168  may be configured to be substantially the same as the thickness of the fingerprint sensor  140  or may be configured to have a particular thickness that can minimize the step difference. However, the present disclosure is limited thereto. For example, if the fingerprint sensor  140  and the cushion member  168  have substantially the same thickness, the step difference between the fingerprint sensor  140  and the pressure sensor  190  can be reduced. Therefore, it may be easier for the pressure sensor  190  to be attached under the fingerprint sensor  140 . The cushion member  168  may be configured to surround the fingerprint sensor  140  to absorb the ultrasonic output from the fingerprint sensor  140 . The cushion member  168  may be disposed between the electroluminescence display panel  110  and the pressure sensor  190 . Accordingly, it can be configured to transmit a portion of the pressure that can be transmitted from the electroluminescence display panel  110  to the pressure sensor  190 . 
     The pressure sensor  190  may be configured to overlap at least a portion of the cushion member  168  and at least a portion of the fingerprint sensor  140 . The area of the pressure sensor  190  may be larger than the area of the fingerprint sensor  140 . The pressure sensor  190  and the fingerprint sensor  140  may be arranged to overlap with each other. The pressure sensor  190  may be disposed under the rear surface of the fingerprint sensor  140 . In addition, it is preferable that the pressure sensor  190  is disposed under the rear surface of the fingerprint sensor  140  because the pressure sensor  190  does not sense the shape of a precise fingerprint such as a fingerprint. If the fingerprint sensor  140  is disposed under the pressure sensor  190 , the sensitivity of the ultrasonic signal may be reduced and the fingerprint recognition rate or the fingerprint-sensing rate may be lowered. 
     The fourth adhesive member  156  may be configured to fix the fingerprint sensor  140 , the pressure sensor  190 , and the cushion member  168  at the same time. The pressure sensor  190  and the fingerprint sensor  140  can be adhered by the fourth adhesive member  156 . The cushion member  168  and the pressure sensor  190  can be adhered by the fourth adhesive member  156 . The pressure sensor  190  may be configured to be wider than the opening of the cushion member  168  and overlap with a portion of the cushion member  168  adjacent to the opening while overlapping with the fingerprint sensor  140 . 
     The first adhesive member  150  and the fourth adhesive member  156  may be made of the same material. The first adhesive member  150  and the fourth adhesive member  156  may be made of materials different from each other. Since the first adhesive member  150  is a path for transmitting and receiving ultrasonic waves to and from the electroluminescence display panel  110 , the Young&#39;s modulus and thickness of the first adhesive member  150  should be determined in consideration of ultrasonic transmission and reception characteristics. Since the fourth adhesive member  156  requires a Young&#39;s modulus capable of transmitting pressure to the pressure sensor  190 , the Young&#39;s modulus and the thickness of the first adhesive member  152  may be less restrictive than those of the first adhesive member  152 . 
     As the Young&#39;s modulus of the fourth adhesive member  156  is low or the thickness is thicker, the pressure transfer characteristics may be reduced. On the other hand, as the Young&#39;s modulus of the fourth adhesive member  156  is high or the thickness is thinner, the pressure transfer characteristics can be improved. However, the fourth adhesive member  156  may take into account not only the pressure transmission characteristic but also the shock absorption characteristic transmitted to the fingerprint sensor  140 . 
     For example, when the Young&#39;s modulus of the fourth adhesive member  156  is low, when the impact is transmitted to the fingerprint sensor  140  through the electroluminescence display panel  110 , the fingerprint sensor  140  may be damaged. In addition, the fingerprint sensor  140  may be made of a material having a high Young&#39;s modulus value suitable for generating ultrasonic waves for fingerprint recognition. In this case, it may be vulnerable to breakage. When the Young&#39;s modulus of the fourth adhesive member  156  is relatively lower than the Young&#39;s modulus of the first adhesive member  152 , the fourth adhesive member  156  may absorb the impact and protect the fingerprint sensor  140 . When the thickness of the fourth adhesive member  156  is thicker than the thickness of the first adhesive member  152 , the fourth adhesive member  156  may absorb the impact and protect the fingerprint sensor  140 . 
     The fingerprint sensor  140  may be configured to turn on the fingerprint sensor  140  when the pressure input through the pressure sensor  190  is equal to or greater than a predetermined threshold value. That is, the pressure sensor  190  may be configured to control the power of the fingerprint sensor  140 . In other words, the power consumption of the fingerprint sensor  140  may be relatively higher than that of the pressure sensor  190 . Therefore, the stand-by power or the power consumption of the fingerprint sensor  140  can be reduced by using the pressure sensor  190 . 
       FIG. 40A  and  FIG. 41A  are cross-sectional views schematically illustrating cross section C′-C″ and D′-D″ corresponding to fingerprint recognition areas of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  3300 A according to the other embodiment of the present disclosure and the display devices as illustrated in  FIG. 1  to  FIG. 39A  according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     A display device  3300 A according to the other embodiment of the present disclosure may include an electroluminescence display panel  110  including a display area AA configured to recognize a fingerprint, a fingerprint sensor  140  positioned in the fingerprint recognition area FDA and a film-type speaker  192 - 1  provided in the first area SPK 1  of the electroluminescence display panel  110 . However, the present disclosure is not limited thereto. Further, another film-type speaker  192 - 2  may be provided in the second area SPK 2  of the electroluminescence display panel  110 . That is, a plurality of film-type speakers may be provided. The light-shield support substrate  174  may be positioned the electroluminescence display panel  110  and the fingerprint sensor  140  and may be positioned between the electroluminescence display panel  110  and the film-type speakers ( 192 - 1 ,  192 - 2 ). 
     The electroluminescence display panel  110  of the display device  3300 A may include a substrate configured to be an output path of the ultrasonic transmission and reception channel of the fingerprint sensor  140  and the film type speakers ( 192 - 1 ,  192 - 2 ), a transistor on the substrate, an electroluminescence element on the transistor, and an encapsulation on the electroluminescent element. Further, the substrate of the electroluminescence display panel  110  may be configured to have a flexible characteristic to transmit pressure of the user&#39;s finger. 
     A display device  3300 A may include an electroluminescence display panel  110  configured to output sound and to display an image, a fingerprint sensor  140  configured to enable fingerprint recognition using an ultrasonic method through the electroluminescence display panel  110 , and a film type speaker ( 192 - 1 ,  192 - 2 ) under the rear side of the fingerprint sensor  140 . 
     As an example, a plurality of film-type speakers ( 192 - 1 ,  192 - 2 ) may be composed of a piezoelectric speaker and may be configured to include an actuator of a piezoelectric element. That is, the film-type speaker may be a piezo speaker including a piezoelectric element. That is, the audible frequency vibration output from the speaker may vibrate the electroluminescence display panel  110  bonded to the film-type speakers  192 - 1  and  192 - 2 , and by the vibration of the electroluminescence display panel  110 , sound may be provided to the user. 
     The cushion member  168  may be positioned under the rear side of the light-shield support substrate  174  and may be configured to surround the fingerprint sensor  140 . The cushion member  168  may be positioned between the film-type speaker and the electroluminescence display panel  110 , and may be configured to transmit sound in a band of 20 KHz or less while absorbing ultrasonic waves in a band of 10 MHz or more. 
     At least one film-type speaker of the plurality of film-type speakers ( 192 - 1 ,  192 - 2 ) may be overlapped with the cushion member  168 . At least one film-type speaker of the plurality of film-type speakers ( 192 - 1 ,  192 - 2 ) may be overlapped with the fingerprint sensor  140 . In addition, the cushion member  168  may be removed according to the output characteristics of the frequency band of the film-type speaker. In addition, the cushion member may be a foam tape, and the cushion member can relatively absorb the sound of the high frequency band relative to the low frequency band. Therefore, when the output of the high-frequency band of the film-type speaker is insufficient, the cushion member of the region where the corresponding film-type speaker is arranged may be removed. 
     The film-type speaker may be configured to output sound in the direction toward the electroluminescence display panel  110 . However, the present disclosure is not limited thereto, and it may be configured to output sound in the opposite direction to the electroluminescence display panel  110 , or to output sound in both directions. 
     The plurality of film-type speakers ( 192 - 1 ,  192 - 2 ) may be at least two or more, and each of the film-type speakers may be spaced apart from each other under the electroluminescence display panel  110 . 
     In some embodiments, at the rear surface of the cushion member, a metallic diaphragm for amplifying the output of the film-type speaker may be provided. The film-type speaker can be configured to output sound through a metallic diaphragm and a fingerprint sensor. 
     In some embodiments, the display device may include a plurality of pixels on a flexible substrate, a cushion member, under the flexible substrate, including at least one opening, a film-type speaker, under the cushion member, adhered to the periphery of the at least one opening to output sound, and a fingerprint sensor between the film-type speaker and the flexible substrate. In this case, the film-type speaker (e.g., piezo speaker) may be configured to transmit sound through the fingerprint sensor. 
     In some embodiments, a display device may be positioned between a film-type speaker and a cushion member. Further, a heat dissipation member configured to dissipate heat of the film-type speaker and the fingerprint sensor may be included. 
       FIG. 39B ,  FIG. 40B  and  FIG. 41B  are cross-sectional views schematically illustrating cross section B′-B″, C′-C″ and D′-D″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  3300 B according to the other embodiment of the present disclosure and the display devices as illustrated in  FIG. 1  to  FIG. 39A ,  FIG. 40A  and  FIG. 41A , according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     Referring to  FIG. 39B ,  FIG. 40B  and  FIG. 41B , a display device  3300 B according to the other embodiment of the present disclosure may include an EMI shield member  170  disposed between an electroluminescence display panel  110  and a cushion member  168 . Specifically, the EMI shield member  170  may be disposed between a light-shield support substrate  174  and the cushion member  168 . 
     The EMI shield member  170  may be made of a conductive material. For example, the EMI shield member  170  may comprise metallic particles or may be a metal foil. The EMI shield member  170  may be coated directly at the rear side of the light-shield support substrate  174  or may be bonded together through a separate bonding member. The EMI shield member  170  may be a metal layer, for example, including copper (cu) and may be configured to shield external light transmitted through the electroluminescence display panel  110 . In addition, the EMI shield member  170  may be a conductive ink. The EMI shield member  170  may be coated or printed directly under the rear side of the light-shield support substrate  174 . In addition, the EMI shield member  170  may be a thin metal film. The EMI shield member  170  may be deposited on the light-shield support substrate  174 . 
     Accordingly, when the EMI shield member  170  is formed directly on the light-shield support substrate  174 , since an adhesive member is unnecessary, an additional adhesive member may not be required even if the EMI shield member  170  is added. Therefore, it is possible to improve the image quality of the electroluminescence display panel  110  and the fingerprint recognition sensitivity of the fingerprint sensor  140  while maintaining the signal sensitivity of the fingerprint sensor  140 . 
     Referring to  FIG. 39B , the EMI shield member  170  may be configured to shield at least a region where the fingerprint sensor  140  and the electroluminescence display panel  110  are overlapped. For example, the EMI shield member  170  may be configured to shield at least the fingerprint recognition area FDA. However, the present disclosure is not limited thereto. Further, the EMI shield member  170  may be configured to shield the fingerprint recognition area FDA and at least a portion of the display area AA. That is, the EMI shield member  170  may be configured to shield at least the electromagnetic interference noise between the electroluminescence display panel  110  and the fingerprint sensor  140  by shielding at least the fingerprint recognition area FDA. 
     In addition, referring to  FIG. 40B  and  FIG. 41B , the EMI shield member  170  may be configured to shield at least a region where a plurality of film-type speakers  192 - 1  and  192 - 2  and the electroluminescence display panel  110  are overlapped. For example, the EMI shield member  170  may be configured to shield at least a first area SPK 1  and a second area SPK 2  of the electroluminescence display panel  110 . However, the present disclosure is not limited thereto. Further, the EMI shield member  170  may be configured to shield the first area SPK 1  and the second area SPK 2  of the electroluminescence display panel  110  and at least a portion of the display area AA. That is, the EMI shield member  170  may be configured to shield at least the electromagnetic interference noise between the electroluminescence display panel  110  and the plurality of film-type speakers  192 - 1  and  192 - 2  by shielding at least the first area SPK 1  and the second area SPK 2  of the electroluminescence display panel  110 . 
     Therefore, the deterioration in image quality of the electroluminescence display panel  110  due to the electromagnetic interference generated by the operations of the fingerprint sensor  140  of the ultrasonic type and the film-type speakers  192 - 1  and  192 - 2  which are piezoelectric speakers can be suppressed, but also, at the same time, the deterioration in fingerprint recognition sensitivity of the fingerprint sensor  140  due to the electromagnetic interference of the electroluminescence display panel  110  can be suppressed. 
       FIG. 39C ,  FIG. 40C  and  FIG. 41C  are cross-sectional views schematically illustrating cross section B′-B″, C′-C″ and D′-D″ corresponding to a fingerprint recognition area of a display device including an electroluminescence display panel capable of providing a fingerprint recognition function, a pressure sensing function, and a speaker function according to the other embodiment of the present disclosure. 
     Redundant features of the display device  3300 C according to the other embodiment of the present disclosure and the display devices as illustrated in  FIG. 1  to  FIG. 39A ,  FIG. 40A  and  FIG. 41A , according to the other embodiments of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     Referring to  FIG. 39C ,  FIG. 40C  and  FIG. 41C , the display device  3300 C according to the other embodiment of the present disclosure may be configured to include a heat dissipation member  164  disposed under a rear surface of the cushion member  168 . 
     The heat dissipation member  164  may be configured to surround the fingerprint sensor  140  and overlap a portion of the display area AA to perform the function of a heat sink for the electroluminescence display panel  110 . For example, the heat dissipation member  164  may be disposed to correspond to an area of the cushion member  168  under the rear surface of the cushion member  168 . 
     The heat dissipation member  164  may be made of a material having a high thermal conductivity. For example, the heat dissipation member  164  may be made of a material such as metal, graphite, and/or graphene. For example, the thickness of the heat dissipation member  164  may be 50 μm to 100 μm. However, the present disclosure is not limited thereto 
     According to the above-described configuration, the temperature deviation between the fingerprint sensor  140  and periphery of the fingerprint sensor  140  can be reduced by the heat dissipation member  164 . Therefore, it is possible to reduce the occurrence of image retention due to the attachment of the fingerprint sensor  140 . 
     In addition, when the heat dissipation member  164  is a conductive material, the heat dissipation member  164  can be electrically grounded. However, the present disclosure is not limited thereto. 
     Referring to  FIG. 40C  and  FIG. 41C , the heat dissipation member  164  may be disposed between the film-type speakers  192 - 1  and  192 - 2  and the cushion member  168 . Accordingly, the heat dissipation member  164  may be disposed between the electroluminescence display panel  110  and the film type speakers  192 - 1  and  192 - 2 . The temperature of an area where the film type speakers  192 - 1  and  192 - 2  are attached may increase depending on the output of the film type speakers  192 - 1  and  192 - 2 . If a temperature difference occurs between the area where the film type speakers  192 - 1  and  192 - 2  are attached and the area where the film type speakers  192 - 1  and  192 - 2  are not attached, a temperature deviation of the electroluminescence display panel  110  may occur and a residual image may appear on the displayed image. That is, the heat dissipation member  164  can reduce the temperature deviation. 
       FIG. 42  is a cross-sectional view illustrating a stack structure of an exemplary electroluminescence display panel which can be applied to a cross-section A′-A″ of a display device according to the other embodiment of the present disclosure. 
     Redundant features of the display device  3400  according to the other embodiment of the present disclosure and the display device  100  according to an embodiment of the present disclosure may be omitted merely for the sake of convenience of explanation. 
     The electroluminescence display panel  210  of the display device  3400  according to the other embodiment of the present disclosure may be configured to include an integrated touch panel  220 . The integrated touch panel  220  may be formed on the encapsulation unit ( 128 ,  130 ,  132 ). 
     The integrated touch panel  220  may be formed by depositing electrode layers ( 222 ,  226 ) and insulating layers ( 224 ,  228 ) on the encapsulation unit ( 128 ,  130 ,  132 ) during the manufacturing process of the electroluminescence display panel  210 . That is, the integrated touch panel  220  does not require an additional substrate for forming a separate touch panel. Thus, the integrated touch panel  220  may be formed on the encapsulation unit ( 128 ,  130 ,  132 ) of the electroluminescence display panel  210 , thereby minimizing the thickness increase and the signal sensitivity degradation of the transmitting and receiving channel for the ultrasonic fingerprint recognition. 
     By forming the integrated touch panel  220 , an unnecessary adhesion process and an unnecessary adhesive member for bonding the conventional touch panel and the electroluminescence display panel can be eliminated. Accordingly, it is possible to remove an adhesive member having a low Young&#39;s modulus, which may deteriorate ultrasonic transmission and reception sensitivity, from being positioned between the integrated touch panel  220  and the electroluminescence display panel  210 . 
     Each layer of the integrated touch panel  220  of the electroluminescence display panel  210  according to the other embodiment of the present disclosure may be formed of a material having a high Young&#39;s modulus value, for example, the integrated touch panel  220  may be made of a metal material and an inorganic thin film. Thus, the thickness of the ultrasonic transmission and reception channel  220  can be reduced. Therefore, the deterioration of the signal sensitivity of the ultrasonic transmission and reception channel can be minimized. A touch buffer layer  212  may be disposed between the encapsulation unit  132  and the integrated touch panel  220 . When the integrated touch panel  220  is formed on the encapsulation unit ( 128 ,  130 ,  132 ), the touch buffer layer  212  may protect the pad portion formed in the non-display area NA of the electroluminescence display panel  210  from being corroded during an etching process. The thickness of the touch buffer layer  212  may be smaller than the thickness of the second inorganic encapsulation layer  132 . The touch buffer layer  212  may be formed of an inorganic film such as silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON). The thickness of the touch buffer layer  212  may be 0.1 μm to 0.4 μm. However, the present disclosure is not limited thereto, and the touch buffer layer  212  may be removed. 
     The first touch electrode layer  222  of the integrated touch panel  220  may be formed of a metallic conductive material having a low electrical resistance. However, the present disclosure is not limited thereto. The first touch electrode layer  222  may have a single-layer structure or a multi-layer structure. The first touch electrode layer  222  may be formed in the form of a metal-mesh that has a width narrower than the width of the bank  124 . The first touch electrode layer  222  may configure a portion of a driving electrode, a sensing electrode, and/or a bridge electrode of the integrated touch panel  220 . For example, the thickness of the first touch electrode layer  222  may be 0.2 μm to 0.5 μm. However, the present disclosure is not limited thereto. 
     The first touch insulation layer  224  may be disposed on the first touch electrode layer  222 . The first touch insulation layer  224  may insulate the first touch electrode layer  222  from the second touch electrode layer  226 . The first touch insulation layer  224  may be formed of an inorganic film such as silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON). For example, the thickness of the first touch insulation layer  224  may be 0.2 μm to 0.5 μm. However, the present disclosure is not limited thereto. 
     The second touch electrode layer  226  may be disposed on the first touch insulation layer  224 . The second touch electrode layer  226  may be preferably made of a metallic conductive material having a low electrical resistance. The second touch electrode layer  226  may have a single-layer structure or a multi-layer structure. The second touch electrode layer  226  may be formed in the form of a metal-mesh that has a width narrower than the width of the bank  124 . The second touch electrode layer  226  may configure another portion of the driving electrode, the sensing electrode, and/or the bridge electrode of the integrated touch panel  220 . For example, the thickness of the second touch electrode layer  226  may be 0.2 μm to 0.5 μm. However, the present disclosure is not limited thereto. 
     A portion of the first touch electrode layer  222  and a portion of the second touch electrode layer  226  are electrically connected to each other through a contact hole formed in the first touch insulation layer  224  to form a bridge portion. 
     The second touch insulation layer  228  may be disposed on the second touch electrode layer  226 . The second touch insulation layer  228  may be configured to cover the second touch electrode layer  226 . The second touch insulation layer  228  may be formed of an inorganic film such as silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON), or an organic film such as an acryl material, epoxy material, Parylene-C, Parylene-N, or Parylene-F, or a siloxane-based organic film. For example, the thickness of the second touch insulation layer  228  may be 0.2 μm to 3 μm. However, the present disclosure is not limited thereto. 
     The second touch insulation layer  228  may prevent corrosion of the second touch electrode layer  226  or may insulate the second touch electrode layer  226 . However, the present disclosure is not limited to the second touch insulation layer  228 . In some cases, the second touch insulation layer  228  may be omitted. 
     The integrated touch panel  220  of the electroluminescence display panel  210  according to the other embodiment of the present disclosure may be formed of a capacitive touch panel. The integrated touch panel  220  may include a first touch electrode layer  222  on the encapsulation unit  132 , a first touch insulation layer  224  on the first touch electrode layer  222 , a second touch electrode  226  on the first touch insulation layer  224 , and a second touch insulation layer  228  on the second touch electrode  226 . Each of the layers configuring the integrated touch panel  220  may be made of a material having a Young&#39;s modulus of at least 1 GPa or more. In addition, the integrated touch panel  220  may have a thickness of 0.8 μm to 4.5 μm to minimize the signal sensitivity reduction of the ultrasonic transmission and reception channel of the fingerprint sensor. 
     The polarizer  242  may be further included on the integrated touch panel  220 . The polarizer  242  may be configured to absorb ambient light reflection. A polarizer adhesive member  240  capable of bonding the polarizer  242  and the integrated touch panel  220  may be applied between the polarizer  242  and the integrated touch panel  220 . It is preferable that the polarizer adhesive member  240  is made of an adhesive member having a high Young&#39;s modulus in consideration of ultrasonic transmission and reception characteristics. However, the present disclosure is not limited thereto. In addition, it is possible that the polarizer  242  and the polarizer adhesive member  240  are omitted. 
     A cover  246  may be further included on the polarizer  242 . The cover  246  may be configured to protect the electroluminescence display panel  210 . The cover  246  is glass in one embodiment. A cover adhesive member  244  capable of bonding the cover  264  and the polarizer  242  may be applied between the cover  246  and the polarizer  242 . The cover adhesive member  244  is preferably made of an adhesive member having a high Young&#39;s modulus in consideration of ultrasonic transmission and reception characteristics. However, the present disclosure is not limited thereto. In addition, it is possible that the cover  246  and the cover adhesive member  244  are omitted. Further, the Young&#39;s modulus of the cover may be 50 GPa or more. 
     The controller of the fingerprint sensor  140  may generate ultrasonic waves of a suitable frequency to pass through the cover  246  on the front surface of the electroluminescence display panel  110 . For example, ultrasonic waves having a frequency of 10 MHz to 15 MHz can be generated and then transmitted and received through the Tx electrodes  141  and the Rx electrodes  143 . 
     In some embodiments, it is also possible to provide various functional layers on the touch panel, such as a protective film, an antistatic film, a polarizing film, an ambient light absorbing film, a protective glass, and the like. 
     A means implemented to be attachable to the rear surface of the electroluminescence display panel according to various embodiments of the present disclosure can be referred to an arrangement means of the present disclosure. For example, various adhesive members, a light-shield member, a support substrate, a heat dissipation member, a cushion member, an EMI shield member, a light and EMI shield member, a light-shield support substrate, a pressure sensor and the like can be referred to an arrangement means. 
     Embodiments of the present disclosure can also be described as follows: 
     A display device according to an embodiment of the present disclosure may include a display area including a fingerprint recognition area and a plurality of pixels and disposed on a substrate, an ultrasonic fingerprint sensor, corresponding to the fingerprint recognition area, disposed under the substrate, and a pressure sensor disposed under a rear side of the ultrasonic fingerprint sensor. 
     The display device may further include a support substrate disposed between the ultrasonic fingerprint sensor and the substrate. 
     The display device may further include a cushion member configured to surround the ultrasonic fingerprint sensor and positioned under a rear side of the support substrate. 
     The pressure sensor may be overlapped with at least a portion of the cushion member and at least a portion of the ultrasonic fingerprint sensor. 
     The ultrasonic fingerprint sensor may be configured to transmit ultrasonic waves to a fingerprint and may be configured to receive the reflected ultrasonic waves to recognize the fingerprint touched on the fingerprint recognition area. 
     The ultrasonic fingerprint sensor may be configured to turn on the ultrasonic fingerprint sensor when a pressure input through the pressure sensor is equal to or greater than a predetermined threshold value. 
     The display device may further include an adhesive member configured to attach the ultrasonic fingerprint sensor, the pressure sensor, and the cushion member. 
     A display device according to another embodiment of the present disclosure may include an electroluminescence display panel configured to display an image, a fingerprint sensor positioned under a rear surface of the electroluminescence display panel, and a pressure sensor configured to sense a pressure applied to the electroluminescence display panel and positioned under the fingerprint sensor, wherein a front surface of the fingerprint sensor is attached to the rear surface of the electroluminescence display panel by a first adhesive member, and wherein a rear surface of the fingerprint sensor is attached to the pressure sensor by a second adhesive member. 
     The display device may include a cushion member positioned between the electroluminescence display panel and the fingerprint sensor and configured to transmit at least a part of a pressure transmitted from the electroluminescence display panel. 
     The first adhesive member and the second adhesive member may be made of the same material. 
     The first adhesive member and the second adhesive member may be made of materials different from each other. 
     The cushion member may be configured to surround the fingerprint sensor so as to absorb an ultrasonic output from the fingerprint sensor. 
     The display device may further include a transparent cover on the electroluminescence display panel and the transparent cover may have a Young&#39;s modulus value of 50 GPa or more. 
     The electroluminescence display panel may include a substrate, a transistor on the substrate, an electroluminescence element on the substrate, and an encapsulation unit on the electroluminescence element and the substrate, the transistor, the electroluminescence element and the encapsulation unit may be configured to be a channel of the ultrasonic transmission and reception with respect to the fingerprint sensor. 
     A display device according to the other embodiment of the present disclosure may include a plurality of pixels on a flexible substrate, a cushion member including at least one opening and positioned under a rear surface of the flexible substrate, at least one pressure sensor and configured to receive a pressure through a periphery of the at least one opening and positioned under a rear surface of the cushion member, and at least one fingerprint sensor positioned between the flexible substrate and the at least one pressure sensor. 
     The at least one pressure sensor may be configured to receive at least a part of the pressure by the corresponding at least one fingerprint sensor. 
     The at least one pressure sensor may be configured to receive at least a part of the pressure by the corresponding cushion member. 
     An area of the pressure sensor may be larger than an area of the fingerprint sensor. 
     The fingerprint sensor and the pressure sensor may be overlapped each other. 
     The pressure sensor may be configured to control a power of the fingerprint sensor. 
     A sensor according to the other embodiment of the present disclosure may include at least one arrangement means implemented to be attachable to a rear surface of an electroluminescence display panel configured to provide visual information to a display area of a display device with an arrangement of a plurality of pixel, an ultrasonic transmission and reception electrode structure implemented to support a function of using ultrasonic waves for an approval of a user through a display area, and a control unit for processing the ultrasonic waves to recognize a fingerprint of the user. 
     The ultrasonic transmission and reception electrode structure may include a transmission electrode for transmitting the ultrasonic waves and a reception electrode for receiving the ultrasonic waves. 
     The control unit may be configured to generate a suitable frequency of the ultrasonic waves so as to pass through a transistor, an electroluminescence element, and an encapsulation unit of the electroluminescence display panel, and may be configured to transmit and receive the ultrasonic waves by using the ultrasonic transmission and reception electrode structure. 
     The control unit may be configured to generate the suitable frequency of the ultrasonic waves so as to pass through a support substrate positioned under a rear side of the electroluminescence display panel, and may be configured to transmit and receive the ultrasonic waves by using the ultrasonic transmission and reception electrode structure. 
     The control unit may be configured to generate the suitable frequency of the ultrasonic waves so as to pass through a cover positioned on a front side of the electroluminescence display panel, and may be configured to transmit and receive the ultrasonic waves by using the ultrasonic transmission and reception electrode structure. 
     The control unit may be configured to generate the suitable frequency of the ultrasonic waves so as to pass through an EMI shield member positioned under the support substrate, and may be configured to transmit and receive the ultrasonic waves by using the ultrasonic transmission and reception electrode structure. 
     The control unit may be configured to generate the suitable frequency of the ultrasonic waves so as to pass through a light-shield member positioned under the EMI shield member, and may be configured to transmit and receive the ultrasonic waves by using the ultrasonic transmission and reception electrode structure. 
     Embodiments of the present disclosure may disclose various structures and elements enabling a user&#39;s fingerprint recognition by contacting a user&#39;s finger on a display area of a display device with an ultrasonic fingerprint sensor, a pressure sensor, and/or a film-type speaker attached to the electroluminescence display panel. The various elements of the present disclosure may also be used for solving various problems that may arise when providing fingerprint recognition, pressure recognition and/or audio function. For example, disclosed elements of the present disclosure may be configured to improve above-described problems such as fingerprint recognition speed decrease, fingerprint recognition rate decrease, temperature deviation, image retention, flatness degradation, damage by an impact. Thus, each of the elements of the present disclosure can be selected as needed for solving various. 
     Although the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, the present disclosure is not limited thereto and may be embodied in many different forms without departing from the technical concept of the present disclosure. Therefore, the embodiments of the present disclosure are provided for illustrative purposes only but not intended to limit the technical spirit of the present disclosure. The scope of the technical spirit of the present disclosure is not limited thereto. Therefore, it should be understood that the above-described embodiments are illustrative in all aspects and do not limit the present disclosure. The protective scope of the present disclosure should be construed based on the following claims, and all the technical concepts in the equivalent scope thereof should be construed as falling within the scope of the present disclosure.