Patent Publication Number: US-2021182521-A1

Title: Display device with fingerprint identification function

Description:
FIELD OF INVENTION 
     The present disclosure relates to the field of display devices, and more particularly, to a display device with a fingerprint identification function. 
     BACKGROUND OF INVENTION 
     Phones usually use front buttons (such as IPHONEs) or back capacitance (such as ANDROID phones) to realize fingerprint identification. However, with demands of full screens and ultra-thin phones, a space for design of fingerprint identification in the phones is increasingly limited, therefore all kinds of embedded fingerprint identification technologies are developed to adapt to full screens, such as an ultrasonic mode under a screen or an optic mode with grating effects. 
     However, the above technologies increase thicknesses of the phones, therefore solutions need to be provided to solve problem in existing technologies. 
     SUMMARY OF INVENTION 
     An object of the present disclosure is to provide a display device with a fingerprint identification function to solve the problem of increased thickness of a phone caused by an ultrasonic mode under a screen or an optic mode with grating effects in the existing technologies. 
     To achieve the above object, an embodiment of the present disclosure provides a display device with a fingerprint identification function. The display device includes a display panel including a display area and a non-display area; and an ultrasonic fingerprint identification module disposed inside an upper surface of the display device with the fingerprint identification function, and including a substrate; a reflecting layer disposed on the substrate; a plurality of microcrystalline particles distributed in the reflecting layer; and an ultrasonic generating and receiving unit disposed on a side of the reflecting layer. A distribution area of the plurality of microcrystalline particles correspond to the display area of the display panel, and a diameter of each of the microcrystalline particles ranges between 0.01 and 3 micrometers. 
     In an embodiment of the present disclosure, the ultrasonic generating and receiving unit corresponds to the non-display area of the display panel. 
     In an embodiment of the present disclosure, the display device further includes a plurality of ultrasonic generating and receiving units disposed on two sides of the reflecting layer. 
     In an embodiment of the present disclosure, a number of the plurality of microcrystalline particles increases with increasing distance from the ultrasonic generating and receiving unit. 
     In an embodiment of the present disclosure, a number of the plurality of microcrystalline particles decreases with increasing distance from the ultrasonic generating and receiving unit. 
     To achieve the above object, an embodiment of the present disclosure provides a display device with a fingerprint identification function. The display device includes a display panel including a display area and a non-display area; and an ultrasonic fingerprint identification module disposed inside an upper surface of the display device with the fingerprint identification function, and including a substrate; a reflecting layer disposed on the substrate; a plurality of microcrystalline particles distributed in the reflecting layer; and an ultrasonic generating and receiving unit disposed on a side of the reflecting layer. 
     In an embodiment of the present disclosure, a distribution area of the plurality of microcrystalline particles correspond to the display area of the display panel. 
     In an embodiment of the present disclosure, a diameter of each of the microcrystalline particles ranges between 0.01 and 3 micrometers. 
     In an embodiment of the present disclosure, the ultrasonic generating and receiving unit corresponds to the non-display area of the display panel. 
     In an embodiment of the present disclosure, the display device further includes a plurality of ultrasonic generating and receiving units disposed on two sides of the reflecting layer. 
     In an embodiment of the present disclosure, a number of the plurality of microcrystalline particles increases with increasing distance from the ultrasonic generating and receiving unit. 
     In an embodiment of the present disclosure, a number of the plurality of microcrystalline particles decreases with increasing distance from the ultrasonic generating and receiving unit. 
     To achieve the above object, an embodiment of the present disclosure provides a display device with fingerprint identification function. The display device includes a display panel including a display area and a non-display area; and an ultrasonic fingerprint identification module embedded in the display panel, and including a reflecting layer disposed in the display panel; a plurality of microcrystalline particles distributed in the reflecting layer; and an ultrasonic generating and receiving unit disposed on a side of the reflecting layer. 
     In an embodiment of the present disclosure, the display panel includes a first layer; a second layer disposed on the first layer and configured to display an image together with the first layer; and a touch layer disposed on the second layer and configured to sense signals applying on the display panel. 
     In an embodiment of the present disclosure, the display device further includes a polarizer disposed on the ultrasonic fingerprint identification module; and a protective layer disposed on the polarizer. 
     Compared to the existing technologies, in the display device with the fingerprint identification function of the present disclosure, the ultrasonic generating and receiving unit is disposed on the side of the reflecting layer, which decreases the thickness of the display device. Furthermore, the distribution area of the plurality of microcrystalline particles correspond to the display area of the display panel, which realizes a design of a full screen. 
    
    
     
       DESCRIPTION OF DRAWINGS 
       The accompanying figures to be used in the description of embodiments of the present disclosure or prior art will be described in brief to more clearly illustrate the technical solutions of the embodiments or the prior art. The accompanying figures described below are only part of the embodiments of the present disclosure, from which figures those skilled in the art can derive further figures without making any inventive efforts. 
         FIG. 1  is a side view of an ultrasonic fingerprint identification module according to an embodiment of the present disclosure. 
         FIG. 2  is a top view of a display device with a fingerprint identification function according to an embodiment of the present disclosure. 
         FIG. 3  is a diagram that illustrates ultrasonic waves generated by an ultrasonic generating and receiving unit are reflected by a microcrystalline particle according to an embodiment of the present disclosure. 
         FIG. 4  is a diagram that illustrates ultrasonic waves generated by an ultrasonic generating and receiving unit are reflected by a plurality of microcrystalline particles according to an embodiment of the present disclosure. 
         FIG. 5  is a diagram that illustrates ultrasonic waves reflected from a plurality of microcrystalline particles are reflected by a fingerprint according to an embodiment of the present disclosure. 
         FIG. 6  is a side view of an ultrasonic fingerprint identification module according to another embodiment of the present disclosure. 
         FIG. 7  is a top view of a display device with a fingerprint identification function according to another embodiment of the present disclosure. 
         FIG. 8  is a diagram that illustrates ultrasonic waves generated by an ultrasonic generating and receiving unit are reflected by a microcrystalline particle according to another embodiment of the present disclosure. 
         FIG. 9  is a diagram that illustrates ultrasonic waves generated by an ultrasonic generating and receiving unit are reflected by a plurality of microcrystalline particles according to another embodiment of the present disclosure. 
         FIG. 10  is a diagram that illustrates ultrasonic waves reflected from a plurality of microcrystalline particles are reflected by a fingerprint according to another embodiment of the present disclosure. 
         FIG. 11  is a side view of a display device with a fingerprint identification function according to another embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The embodiments of the present disclosure are described in detail hereinafter. Examples of the described embodiments are given in the accompanying drawings, wherein the identical or similar reference numerals constantly denote the identical or similar elements or elements having the identical or similar functions. The specific embodiments described with reference to the attached drawings are all exemplary and are intended to illustrate and interpret the present disclosure, which shall not be construed as causing limitations to the present disclosure. 
     In the description of the present disclosure, it should be understood that terms such as “center,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inside,” “outside,” “clockwise,” “counter-clockwise” as well as derivative thereof should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description, do not require that the present disclosure be constructed or operated in a particular orientation, and shall not be construed as causing limitations to the present disclosure. In addition, terms such as “first” and “second” are used herein for purposes of description and are not intended to indicate or imply relative importance or significance. Thus, features limited by “first” and “second” are intended to indicate or imply including one or more than one these features. In the description of the present disclosure, “a plurality of” relates to two or more than two, unless otherwise specified. 
     In the description of the present disclosure, it should be noted that unless there are express rules and limitations, the terms such as “mount,” “connect,” and “bond” should be comprehended in broad sense. For example, it can mean a permanent connection, a detachable connection, or an integrate connection; it can mean a mechanical connection, an electrical connection, or can communicate with each other; it can mean a direct connection, an indirect connection by an intermediate, or an inner communication or an interreaction between two elements. A person skilled in the art should understand the specific meanings in the present disclosure according to specific situations. 
     In the description of the present disclosure, unless specified or limited otherwise, it should be noted that, a structure in which a first feature is “on” or “beneath” a second feature may include an embodiment in which the first feature directly contacts the second feature and may also include an embodiment in which an additional feature is formed between the first feature and the second feature so that the first feature does not directly contact the second feature. Furthermore, a first feature “on,” “above,” or “on top of” a second feature may include an embodiment in which the first feature is right “on,” “above,” or “on top of” the second feature and may also include an embodiment in which the first feature is not right “on,” “above,” or “on top of” the second feature, or just means that the first feature has a sea level elevation greater than the sea level elevation of the second feature. While first feature “beneath,” “below,” or “on bottom of” a second feature may include an embodiment in which the first feature is right “beneath,” “below,” or “on bottom of” the second feature and may also include an embodiment in which the first feature is not right “beneath,” “below,” or “on bottom of” the second feature, or just means that the first feature has a sea level elevation less than the sea level elevation of the second feature. 
     The disclosure herein provides many different embodiments or examples for realizing different structures of the present disclosure. In order to simplify the disclosure of the present disclosure, components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present disclosure. Furthermore, reference numbers and/or letters may be repeated in different examples of the present disclosure. Such repetitions are for simplification and clearness, which per se do not indicate the relations of the discussed embodiments and/or settings. Moreover, the present disclosure provides examples of various specific processes and materials, but the applicability of other processes and/or application of other materials may be appreciated by a person skilled in the art. 
     Referring to  FIG. 1  and  FIG. 2 ,  FIG. 1  is a side view of an ultrasonic fingerprint identification module according to an embodiment of the present disclosure.  FIG. 2  is a top view of a display device with a fingerprint identification function according to an embodiment of the present disclosure. 
     The display device with a fingerprint identification function includes a display panel  10  and the ultrasonic fingerprint identification module  20 . 
     The display panel  10  includes a display area  100  and a non-display area  102 . 
     The ultrasonic fingerprint identification module  20  includes a substrate  200 , a reflecting layer  202 , a plurality of microcrystalline particles (crystalline grains)  204 , and at least one ultrasonic generating and receiving unit  206 . The ultrasonic fingerprint identification module  20  is disposed inside an upper surface of the display device with the fingerprint identification function. 
     The reflecting layer  202  is disposed on the substrate  200 . The reflecting layer  202  can be a hyaline layer and is made of organic materials. The organic materials can be acrylic organic materials. 
     The plurality of microcrystalline particles  204  are distributed and formed in the reflecting layer  202 . A distribution area of the plurality of microcrystalline particles  204  correspond to the display area  100  of the display panel  10 . A diameter of each of the microcrystalline particles  204  ranges between 0.01 and 3 micrometers. 
     It is understood that, the plurality of microcrystalline particles  204  can be made of, but is not limited to, glass. The plurality of microcrystalline particles  204  can also be made of other materials. 
     The at least one ultrasonic generating and receiving unit  206  is disposed on at least one side of the reflecting layer  202  and corresponds to the non-display area  102  of the display panel  10 . The at least one ultrasonic generating and receiving unit  206  is configured to generate ultrasonic waves and receive ultrasonic waves. 
     The arrangement of the plurality of microcrystalline particles  204  can be a regular arrangement or an irregular arrangement. For example, the number of the plurality of microcrystalline particles  204  increases with increasing distance from the ultrasonic generating and receiving unit  206 , or the number of the plurality of microcrystalline particles  204  decreases with increasing distance from the ultrasonic generating and receiving unit  206 . 
     Referring to  FIG. 1  to  FIG. 5 ,  FIG. 3  is a diagram that illustrates ultrasonic waves generated by the ultrasonic generating and receiving unit  206  are reflected by a microcrystalline particle  204 .  FIG. 4  is a diagram illustrates that ultrasonic waves generated by the ultrasonic generating and receiving unit  206  are reflected by the plurality of microcrystalline particles  204 .  FIG. 5  is a diagram that illustrates ultrasonic waves reflected from the plurality of microcrystalline particles  204  are reflected by a fingerprint  30 . 
     Referring to  FIG. 3  and  FIG. 4 , when the ultrasonic waves  40  generated by the ultrasonic generating and receiving unit  206  propagate in the reflecting layer  202  (shown in  FIG. 1 ), a part of the ultrasonic waves  40  are reflected to the upper surface of the display panel  10  (shown in  FIG. 2 ) by the microcrystalline particles  204 . The display area  100  of the display panel  10  (shown in  FIG. 2 ) correspond to the plurality of microcrystalline particles  204 , therefore the ultrasonic waves  42  reflected from the plurality of microcrystalline particles  204  reach to the whole upper surface of the display panel  10  (shown in  FIG. 2 ) and form an ultrasonic array on the whole upper surface of the display panel  10  (shown in  FIG. 2 ). Referring to  FIG. 5 , when the fingerprint  30  touches the display panel  10  (shown in  FIG. 2 ), a part of ultrasonic waves  44  reflected from the fingerprint  30  are reflected by the plurality of microcrystalline particles  204 , then a part of ultrasonic waves  46  reflected from the plurality of microcrystalline particles  204  are reflected back to the ultrasonic generating and receiving unit  206  and form fingerprint feedback information through signal processing, then fingerprint identification is finished. 
     In the display device with the fingerprint identification function of the present disclosure, the ultrasonic generating and receiving unit  206  is disposed on the side of the reflecting layer  202 , which decreases the thickness of the display device. Furthermore, the distribution area of the plurality of microcrystalline particles  204  correspond to the display area  100  of the display panel  10 , which realizes a design of a full screen. 
     Referring to  FIG. 6  and  FIG. 7 ,  FIG. 6  is a side view of an ultrasonic fingerprint identification module according to another embodiment of the present disclosure.  FIG. 7  is a top view of a display device with a fingerprint identification function according to another embodiment of the present disclosure. 
     The display device with a fingerprint identification function includes a display panel  50  and the ultrasonic fingerprint identification module  60 . 
     The display panel  50  includes a display area  500  and a non-display area  502 . 
     The ultrasonic fingerprint identification module  60  includes a substrate  600 , a reflecting layer  602 , a plurality of microcrystalline particles  604 , and a plurality of ultrasonic generating and receiving units  606 . The ultrasonic fingerprint identification module  60  is disposed inside an upper surface of the display device with the fingerprint identification function. 
     The reflecting layer  602  is disposed on the substrate  600 . The reflecting layer  602  can be a hyaline layer and is made of organic materials. The organic materials can be acrylic organic materials. 
     The plurality of microcrystalline particles  604  are distributed and formed in the reflecting layer  602 . A distribution area of the plurality of microcrystalline particles  604  correspond to the display area  500  of the display panel  50 . A diameter of each of the microcrystalline particles  604  ranges between 0.01 and 3 micrometers. 
     It is understood that, the plurality of microcrystalline particles  604  can be made of, but is not limited to, glass. The plurality of microcrystalline particles  604  can also be made of other materials. 
     The difference between the display device with the fingerprint identification function in this embodiment and the display device with the fingerprint identification function in the embodiment of  FIG. 2  is that the display device with the fingerprint identification function in this embodiment includes a plurality of ultrasonic generating and receiving units  606  disposed on two sides of the reflecting layer  202 . The plurality of ultrasonic generating and receiving units  606  correspond to the non-display area  502  of the display panel  50 . The plurality of ultrasonic generating and receiving units  606  are configured to generate ultrasonic waves and receive ultrasonic waves. 
     The arrangement of the plurality of microcrystalline particles  604  can be a regular arrangement or an irregular arrangement. For example, the number of the plurality of microcrystalline particles  604  increases with increasing distance from the ultrasonic generating and receiving unit  606 , or the number of the plurality of microcrystalline particles  604  decreases with increasing distance from the ultrasonic generating and receiving unit  606 . 
     Referring to  FIG. 6  to  FIG. 10 ,  FIG. 8  is a diagram that illustrates ultrasonic waves generated by the ultrasonic generating and receiving unit  606  are reflected by a microcrystalline particle  604 .  FIG. 9  is a diagram that illustrates ultrasonic waves generated by the ultrasonic generating and receiving unit  606  are reflected by a plurality of microcrystalline particles  604 .  FIG. 10  is a diagram that illustrates ultrasonic waves reflected from the plurality of microcrystalline particles  604  are reflected by a fingerprint  70 . 
     Referring to  FIG. 8  and  FIG. 9 , when the ultrasonic waves  80  generated by the ultrasonic generating and receiving unit  606  propagate in the reflecting layer  602  (shown in  FIG. 6 ), a part of the ultrasonic waves  80  are reflected to the upper surface of the display panel  50  (shown in the  FIG. 7 ) by the microcrystalline particles  604 . The display area  500  of the display panel  50  (shown in  FIG. 7 ) correspond to the plurality of microcrystalline particles  604 , therefore the ultrasonic waves  82  reflected from the plurality of microcrystalline particles  604  reach to the whole upper surface of the display panel  50  (shown in  FIG. 7 ) and form an ultrasonic array on the whole upper surface of the display panel  50  (shown in  FIG. 7 ). Referring to  FIG. 10 , when the fingerprint  70  touches the display panel  50  (shown in  FIG. 7 ), a part of ultrasonic waves  84  reflected from the fingerprint  70  are reflected by the plurality of microcrystalline particles  604 , then a part of ultrasonic waves  86  reflected from the plurality of microcrystalline particles  604  are reflected back to the ultrasonic generating and receiving unit  606  and form fingerprint feedback information through signal processing, then the fingerprint identification is finished. 
     In the display device with the fingerprint identification function of the present disclosure, the ultrasonic generating and receiving unit  606  is disposed on the side of the reflecting layer  602 , which decreases the thickness of the display device. Furthermore, the distribution area of the plurality of microcrystalline particles  604  correspond to the display area  500  of the display panel  50 , which realizes a design of a full screen. 
     Referring to  FIG. 11 ,  FIG. 11  is a side view of a display device with a fingerprint identification function according to another embodiment of the present disclosure. 
     The display device with a fingerprint identification function includes a display panel  90  and an ultrasonic fingerprint identification module  92 . 
     The ultrasonic fingerprint identification module  92  is disposed in the display panel  90 . The ultrasonic fingerprint identification module  20  of  FIG. 2  is disposed inside the upper surface of the display device with the fingerprint identification function. The ultrasonic fingerprint identification module  60  of  FIG. 7  is also disposed inside the upper surface of the display device with the fingerprint identification function. The ultrasonic fingerprint identification module  92  in this embodiment is embedded in the display panel  90 . 
     The display panel  90  includes a first layer  900 , a second layer  902 , and a touch layer  904 . 
     The second layer  902  is disposed on the first layer  900  and configured to display an image together with the first layer  900 . 
     In an embodiment, the first layer  900  is an array substrate, and the second layer  902  is a color filter if the display panel  90  is a liquid crystal display panel. 
     In another embodiment, the first layer  900  is an array substrate, and the second layer  902  is an emitting layer if the display panel  90  is an organic light emitting diode (OLED) display panel. 
     The touch layer  904  is disposed on the second layer  902  and configured to sense signals applying on the display panel, and the signals can be touching signals or suspended signals. 
     The ultrasonic fingerprint identification module  92  is disposed on the touch layer  904 . The structure of the ultrasonic fingerprint identification module  92  references the relative description of  FIG. 1  and  FIG. 6 . The ultrasonic fingerprint identification module  92  is disposed on the touch layer  904 , therefore the ultrasonic fingerprint identification module  20  and  60  of  FIG. 1  and  FIG. 6  can omit the substrate  200  and  600  correspondingly. 
     Furthermore, the display device with the fingerprint identification function further includes a polarizer  94  and a protective layer  96 . 
     The polarizer  94  is disposed on the ultrasonic fingerprint identification module  92 . 
     The protective layer  96  is disposed on the polarizer  94 . 
     In the display device with the fingerprint identification function of the present disclosure, the ultrasonic generating and receiving unit is disposed on the side of the reflecting layer, which decreases the thickness of the display device. Furthermore, the distribution area of the plurality of microcrystalline particles correspond to the display area of the display panel, which realizes a design of a full screen. 
     The present disclosure has been described with a preferred embodiment thereof. The preferred embodiment is not intended to limit the present disclosure, and it is understood that many changes and modifications to the described embodiment can be carried out without departing from the scope and the spirit of the disclosure that is intended to be limited only by the appended claims.