Patent Publication Number: US-2022223679-A1

Title: Display device

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This is a continuation application of U.S. patent application Ser. No. 16/880,459, filed May 21, 2020 (now pending), the disclosure of which is incorporated herein by reference in its entirety. U.S. patent application Ser. No. 16/880,459 claims priority to and benefit of Korean Patent Application No. 10-2019-0118133 under 35 U.S.C. § 119, filed on Sep. 25, 2019 in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Technical Field 
     The disclosure relates to a display device. 
     2. Description of the Related Art 
     Display devices may include a liquid crystal display (LCD) and an organic light emitting diode (OLED) display. Such display devices are used in various electronic devices such as portable phones, navigation systems, digital cameras, electronic books, portable game consoles, and various terminals. 
     Such display devices may include a display panel including pixels, and a driver for supplying signals to the pixels. Gate lines and data lines may be formed on the display panel, and each pixel may be connected with a gate line and a data line to receive a predetermined signal. The driver may include a gate driver and a data driver. The gate line may receive a gate signal from the gate driver, and the data line may receive a data signal from the data driver. 
     Such a driver may be in the form of a driver IC (Integrated Circuit) chip. The driver IC chip may be attached to one edge of the display panel in a chip-on-glass (COG) method. When bonding between the display panel and the driver IC chip is not properly performed, bonding resistance may increase and adversely affect the driving of the display device. Therefore, the bonding resistance of the driver IC chip after the bonding process may be measured to test whether the display device is properly driven. In this case, there may be a problem that the area of the driver of the display panel may be widened by adding a pad for measuring the bonding resistance to the display panel to measure the bonding resistance. 
     It is to be understood that this background of the technology section is, in part, intended to provide useful background for understanding the technology. However, this background of the technology section may also include ideas, concepts, or recognitions that were not part of what was known or appreciated by those skilled in the pertinent art prior to a corresponding effective filing date of the subject matter disclosed herein. 
     SUMMARY 
     Embodiments are herein described in an effort to solve the above-stated problems by providing a display device that may reduce the area of a driver of a display panel. However, the embodiments are not limited to the solution of only the above-stated problems and may apply to the solutions of other problems as may be appreciated by those of ordinary skill in the art. 
     A display device according to an embodiment may include: a display panel including pixels and a driver IC pad area; a driver IC disposed on the driver IC pad area of the display panel; first input pads and first output pads that overlap the driver IC pad area; a flexible printed circuit disposed adjacent to the driver IC pad area on the display panel; first output test pads that overlap the flexible printed circuit, and are respectively extended to the first output pads; and first input extending wires that overlap the flexible printed circuit, are respectively extended to the first input pads, and are disposed between the first output test pads. 
     The display device according to an embodiment may further include second input pads and second output pads that overlap the driver IC pad area, wherein the first input pads and the second input pads may be symmetric with respect to an imaginary line disposed between the first input pad and the second input pad, and the first output pad and the second output pad may be symmetric with respect to an imaginary line disposed between the first output pads and the second output pads. 
     The first input pads and the second input pads may be linearly arranged adjacent to the flexible printed circuit, and the first output pads and the second output pads may be linearly arranged at a distance from the first input pads and the second input pads. 
     The display device may include: second output test pads that overlap the flexible printed circuit, and are respectively extended to the second output pads; and second input extending wires that overlap the flexible printed circuit, and are extended to the second input pads and disposed between the second output test pads. 
     The display device according to an embodiment may further include: first output extending wires that are respectively extended to the first output pads and the first output test pads; and second output extending wires that are respectively extended to the second output pads and the second output test pads. 
     The display device according to an embodiment may include: second input test pads that overlap the flexible printed circuit, and are respectively extended to the second input pads; and second output extending wires that overlap the flexible printed circuit, and are respectively extended to the second output pads and are disposed between the second input test pads. 
     The display device according to an embodiment may further include: first output extending wires that are respectively extended to the first output pads and the first output test pads; and second input extending wires that are respectively extended to the second input pads and the second input test pads. 
     A constant voltage may be applied to the first output test pads. 
     A display device according to an embodiment may include: a display panel including pixels; a driver IC pad area disposed on the display panel; first input pads and first output pads that overlap the driver IC pad area; a flexible printed circuit disposed adjacent to the driver IC pad area on the display panel; first input test pads that overlap the flexible printed circuit, and are respectively extended to the first input pads; and first output extending wires that overlap the flexible printed circuit, and are respectively extended to the first output pads and are disposed between the first input test pads. 
     The display device according to an embodiment may further include second input pads and second output pads that overlap the driver IC pad area, wherein the first input pads and the second input pads may be symmetric with respect to an imaginary line disposed between the first input pads and the second input pads, and the first output pads and the second output pads are symmetric with respect to an imaginary line disposed between the first output pads and the second output pads. 
     The first input pads and the second input pads may be linearly disposed adjacent to the flexible printed circuit, and the first output pads and the second output pads may be linearly arranged at a distance from the first input pads and the second input pads. 
     The display device according to an embodiment may include: second input test pads that overlap the flexible printed circuit, and are respectively extended to the second input pads; and second output extending wires that overlap the flexible printed circuit, and are respectively extended to the second output pads and disposed between the second input test pads. 
     The display device according to an embodiment may further include: first input extending wires that are respectively extended to the first input pads and the first input test pads; and second input extending wires that are respectively extended to the second input pads and the second input test pads. 
     The display device according to an embodiment may include: second output test pads that overlap the flexible printed circuit, and are respectively extended to the second output pads; and second input extending wires that overlap the flexible printed circuit, and are respectively extended to the second input pads and are disposed between the second output test pads. 
     The display device according to an embodiment may further include: a first input extending wires that are respectively extended to the first input pads and the first input test pads; and second output extending wires that are respectively extended to the second output pads and the second output test pads. 
     A constant voltage may be applied to the first input test pads. 
     A display device according to an embodiment may include: a display panel including pixels; first pads disposed on the display panel; second pads disposed apart from the first pads on the display panel; first test pads respectively extending to the first pads; second test pads respectively extending to the second pads; first extending wires that extending to the first pads and the first test pads; and second extending wires that extending to the second pads and the second test pads, wherein the second test pads are disposed at an edge of the display panel, and the second extending wires are disposed between the first test pads. 
     The first test pads may be linearly arranged along a first direction, and the second test pads may be linearly arranged along the first direction at a distance from the first test pads. 
     In an embodiment, the display panel may include a cutting line between the first test pads and the second test pads. 
     The first test pads may be symmetric with respect to an imaginary line that extends in a second direction perpendicular to the first direction, and the second test pads are symmetrical with respect to the imaginary line. 
     The first pads may be linearly arranged along the first direction, and the second pads may be linearly arranged along the first direction at a distance from the first pads. 
     The first pads may be symmetric with respect to an imaginary line that extends in a second direction perpendicular to the first direction, and the second pads may be symmetric with respect to the imaginary line. 
     According to embodiments, the area of the driving unit of the display panel may be reduced by placing at least a portion of the bonding resistance measuring pad in a portion removed through a cutting or separation or removal process after measuring the bonding resistance. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top plan view of a display device according to an embodiment. 
         FIG. 2  is a block diagram of a region of the display device according to an embodiment. 
         FIG. 3  is a top plan view of the region of  FIG. 2 . 
         FIG. 4  is a schematic cross-sectional view of  FIG. 3 , taken along the line IV-IV 
         FIG. 5  is a schematic cross-sectional view of  FIG. 3 , taken along the line V-V. 
         FIG. 6  is a top plan view of the display device according to an embodiment. 
         FIG. 7  is a block diagram of an area of the display device according to an embodiment. 
         FIG. 8  is a top plan view of the area shown in  FIG. 7 . 
         FIG. 9  is a top plan view of the display device according to an embodiment. 
         FIG. 10  is a block diagram of an area of the display device according to an embodiment. 
         FIG. 11  is a top plan view of the area shown in  FIG. 10 . 
         FIG. 12  is a top plan view of the display device according to an embodiment. 
         FIG. 13  is a block diagram of an area of the display device according to an embodiment. 
         FIG. 14  is a top plan view of the area shown in  FIG. 13 . 
         FIG. 15  is a schematic cross-sectional view of  FIG. 14 , taken along the line XV-XV. 
         FIG. 16  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 17  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 18  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 19  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 20  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 21  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 22  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 23  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 24  is a block diagram of an area of a display device according to an embodiment. 
         FIG. 25  is a block diagram of an area of a display device according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Although the disclosure may be modified in various manners and have additional embodiments, embodiments are illustrated in the accompanying drawings and will be mainly described in the specification. However, the scope of the disclosure is not limited to the embodiments in the accompanying drawings and the specification and should be construed as including all of the changes, equivalents, and substitutions included in the spirit and scope of the disclosure. 
     Some of the parts which are not associated with the description may not be provided in order to describe embodiments of the disclosure and like reference numerals refer to like elements throughout the specification. 
     In the drawings, sizes and thicknesses of elements may be enlarged for better understanding, clarity, and ease of description thereof. However, the disclosure is not limited to the illustrated sizes and thicknesses. In the drawings, the thicknesses of layers, films, panels, regions, and other elements, may be exaggerated for clarity. In the drawings, for better understanding and ease of description, the thicknesses of some layers and areas may be exaggerated. 
     Further, in the specification, the phrase “in a plan view” means when an object portion is viewed from above, and the phrase “in a schematic cross-sectional view” means when a schematic cross-section taken by vertically cutting an object portion is viewed from the side. In addition, in this specification, the phrase “on a plane” means viewing a target portion from the top. 
     Additionally, the terms “overlap” or “overlapped” mean that a first object may be above or below or to a side of a second object, and vice versa. Additionally, the term “overlap” may include layer, stack, face or facing, extending over, covering or partly covering or any other suitable term as would be appreciated and understood by those of ordinary skill in the art. The terms “face” and “facing” mean that a first element may directly or indirectly oppose a second element. In a case in which a third element intervenes between the first and second element, the first and second element may be understood as being indirectly opposed to one another, although still facing each other. When an element is described as ‘not overlapping’ or ‘to not overlap’ another element, this may include that the elements are spaced apart from each other, offset from each other, or set aside from each other or any other suitable term as would be appreciated and understood by those of ordinary skill in the art. 
     It will be understood that when an element such as a layer, film, region, substrate, or area is referred to as being “on” another element, it may be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, intervening elements may be absent therebetween. 
     Further when a layer, film, region, substrate, or area, is referred to as being “below” another layer, film, region, substrate, or area, it may be directly below the other layer, film, region, substrate, or area, or intervening layers, films, regions, substrates, or areas, may be present therebetween. Conversely, when a layer, film, region, substrate, or area, is referred to as being “directly below” another layer, film, region, substrate, or area, intervening layers, films, regions, substrates, or areas, may be absent therebetween. Further, “over” or “on” may include positioning on or below an object and does not necessarily imply a direction based upon gravity. 
     The spatially relative terms “below”, “beneath”, “lower”, “above”, “upper”, or the like, may be used herein for ease of description to describe the relations between one element or component and another element or component as illustrated in the drawings. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to the orientation depicted in the drawings. For example, in the case where a device illustrated in the drawing is turned over, the device positioned “below” or “beneath” another device may be placed “above” another device. Accordingly, the illustrative term “below” may include both the lower and upper positions. The device may also be oriented in other directions and thus the spatially relative terms may be interpreted differently depending on the orientations. 
     Throughout the specification, when an element is referred to as being “connected” to another element, the element may be “directly connected” to another element, or “electrically connected” to another element with one or more intervening elements interposed therebetween. It will be further understood that when the terms “comprises,” “comprising,” “includes” and/or “including” are used in this specification, they or it may specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of other features, integers, steps, operations, elements, components, and/or any combination thereof. 
     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 may be a second component or vice versa according within the spirit and scope of the disclosure. 
     “About” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” may mean within one or more standard deviations, or within ±30%, 20%, 5% of the stated value. 
     In the specification and the claims, the term “and/or” is intended to include any combination of the terms “and” and “or” for the purpose of its meaning and interpretation. For example, “A and/or B” may be understood to mean “A, B, or A and B.” The terms “and” and “or” may be used in the conjunctive or disjunctive sense and may be understood to be equivalent to “and/or.” In the specification and the claims, the phrase “at least one of” is intended to include the meaning of “at least one selected from the group of” for the purpose of its meaning and interpretation. For example, “at least one of A and B” may be understood to mean “A, B, or A and B.” 
     Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an ideal or excessively formal sense unless clearly defined in the specification. 
     A display device according to an embodiment will be described with reference to  FIG. 1  to  FIG. 12 . 
       FIG. 1  to  FIG. 5  illustrate a state before bonding a driving integrated circuit to a display device according to an embodiment.  FIG. 6  to  FIG. 8  illustrate a state after bonding the driving integrated circuit to the display device according to an embodiment.  FIG. 9  to  FIG. 11  illustrate a state after processing a cutting process of the display device according to an embodiment.  FIG. 12  to  FIG. 15  illustrate a state after attaching a flexible printed circuit to the display device according to an embodiment. 
     Hereinafter, referring to  FIG. 1  to  FIG. 5 , a state before bonding a driving integrated circuit to a display device according to an embodiment will be described. 
       FIG. 1  is a top plan view of a display device according to an embodiment,  FIG. 2  is a block diagram of a region of the display device according to an embodiment, and  FIG. 3  is a top plan view of the region of  FIG. 2 .  FIG. 4  is a schematic cross-sectional view of  FIG. 3 , taken along the line IV-IV, and  FIG. 5  is a schematic cross-sectional view of  FIG. 3 , taken along the line V-V. 
     As shown in  FIG. 1 , a display device  1000  according to an embodiment may include a display panel  100  that may display an image or images and may include pixels PX. 
     The display panel  100  may include a display area DA where a screen is displayed, and a peripheral area PA where a driving circuit for driving the display area DA may be mounted. The display panel  100  may be formed of a flexible material and thus may be changed into various shapes. The display panel  100  may be flexible, stretchable, foldable, bendable, or rollable. The display panel  100  may be bent at a boundary between the display area DA and the peripheral area PA. The peripheral area PA may be bent from the display area DA and thus may be located or disposed at a rear side of the display area DA. However, this is merely an example, and the position of the peripheral area PA may be variously changed. 
     The display area DA of the display panel  100  may be formed in the shape of a rectangle including a long side and a short side, and may have a shape having a curved surface by chamfering corner portions. However, such a shape of the display area DA is just an example, and may be changed into various shapes. Pixels PX may be located or disposed in most of the display area DA to enable the display of an image or images. An area where no pixel PX may be located or disposed, for example in an edge area or portion of the display area DA, may correspond to an area where a screen is not located or disposed. 
     The pixels PX may be located or disposed in a matrix format, and receive an image signal and a screen may display an image or images. The arrangement of the pixels PX may be variously changed. Although it is not illustrated, the display panel  100  may include signal lines. The signal lines may include scan lines, control lines, data lines, driving voltage lines, and the like. Signal lines may transmit a scan signal, a control signal, a data signal, a driving voltage, or the like. The signal lines may be located or disposed to cross each other in a row direction or a column direction. Each pixel PX may include transistors connected to the signal lines, a capacitor, and at least one light emitting diode. For example, the display panel  100  may be formed as an organic light emitting display panel. However, the type of the display panel  100  is not restrictive, and may be any of various types of panels. For example, the display panel  100  may be a liquid crystal display panel, an electrophoretic display panel, an electro-wetting display panel, or the like. The display panel  100  may be the next generation display panel such as a micro light emitting diode (microLED) display panel, a quantum dot light emitting diode (QLED) display panel, and a quantum dot organic light emitting diode (QD-OLED) display panel. 
     A light emitting diode with a size in a range of about 10 to about 100 micrometers may form each pixel such that the micro light emitting diode display panel may be formed. The micro light emitting diode display panel may use inorganic materials, color filters and backlights may be omitted, the reaction speed is fast, high luminance may be realized with low power, and it may not break when bent. The quantum dot light emitting diode (QLED) display panel may be formed by attaching a film containing quantum dots or depositing a material containing quantum dots. A quantum dot may be composed of inorganic materials such as indium, cadmium, and the like, and may refer to a particle that emits light by itself and has a diameter of several nanometers or less. By controlling the particle size of the quantum dots, light of a desired color may be displayed. The quantum dot organic light emitting diode (QD-OLED) display panel may use a blue organic light emitting diode as the light source, and may implement a color by attaching a film containing red and green quantum dots or stacking a material containing quantum dots. The display panel  100  according to an embodiment may include various types of display panels. 
     The peripheral area PA of the display panel  100  may include a cutting line CL. It is to be understood that the cutting line is not limited to that of cutting, but instead may include other separation or removal processes within the spirit and the scope of the disclosure. A part of the peripheral area PA of the display panel  100  may be removed in a later cutting process. A portion of the peripheral area PA located or disposed inside or near or adjacent to the cutting line CL may remain as a reference, and a portion located or disposed outside the cutting line CL may be removed. The peripheral area PA of the display panel  100  may include a driver IC pad area ICP and a flexible printed circuit pad area FCP. The driver IC pad area ICP and the flexible printed circuit pad area FCP may be located or disposed in a portion that remains even after the cutting process. For example, the driver IC pad area ICP and the flexible printed circuit pad area FCP may be located or disposed inside or near or adjacent to the cutting line CL. For example, the driver IC pad area ICP may be located or disposed closer to the display area DA of the display panel  100  than the flexible printed circuit pad area FCP. The peripheral area PA of the display panel  100  may include a test pad area TP. The test pad area TP may be removed by the cutting process. The test pad area TP may be located or disposed outside the cutting line CL. The cutting line CL may be located or disposed between the flexible printed circuit pad area FCP and the test pad area TP. The flexible printed circuit pad area FCP may be located or disposed between the driver IC pad area ICP and the test pad area TP. 
     As shown in  FIG. 2 , first input pads  310  and first output pads  210  may be located or disposed in the driver IC pad area ICP of the display panel  100 . Second input pads  320  and second output pads  220  may be located or disposed in the driver IC pad area ICP of the display panel  100 . In the driver IC pad area ICP, the first input pads  310  and the second input pads  320  may be symmetrical (or substantially symmetrical) to each other with respect to an imaginary line IL that is located or disposed between the first input pads  310  and the second input pads  320 . Similarly, in the driver IC pad area ICP, the first output pads  210  and the second output pads  220  may be symmetrical (or substantially symmetrical) to each other with respect to an imaginary line IL that is located or disposed between the first output pads  210  and the second output pads  220 . The imaginary line IL may substantially extend in a vertical direction, and may be located or disposed at a center of the driver IC pad area ICP. Thus, the first input pads  310  and the first output pads  210  may be located or disposed at the left side of the imaginary line IL, and the second input pads  320  and the second output pads  220  may be located or disposed at the right side of the imaginary line IL. However, the embodiment is not limited thereto. The driver IC pad area ICP may be horizontally symmetric (or substantially symmetric in horizontal). However, this is just an example, and an area where at least a part of the driver IC pad area ICP is not symmetrical may exist. 
     The first input pads  310  and the second input pads  320  may be located or disposed at an edge of the driver IC pad area ICP. For example, the first input pads  310  and the second input pads  320  may be located or disposed at an edge that may be adjacent to the flexible printed circuit pad area FCP. The first input pads  310  and the second input pads  320  may be linearly (or substantially linearly) arranged. The first input pads  310  and the second input pads  320  may extend in a direction that may be perpendicular to the imaginary line IL, for example, approximately in a horizontal direction. The first output pads  210  and the second output pads  220  may be located or disposed at an other edge of the driver IC pad area ICP. For example, the first output pads  210  and the second output pads  220  may be located or disposed at an edge that faces the edge where the first input pads  310  and the second input pads  320  may be located or disposed. The first output pads  210  and the second output pads  220  may be linearly (or substantially linearly) arranged at a predetermined distance from the f first input pads  310  and the second input pads  320 . The first output pads  210  and the second output pads  220  may extend in a direction perpendicular to the imaginary line IL, for example, approximately in a horizontal direction. 
     At least one of the first output pads  210  may be connected to the display area DA through a wire. For example, at least one of the first output pads  210  may be connected with a pixel PX of the display area DA through a wire. Similarly, at least one of the second output pads  220  may be connected to the display area DA through a wire. 
     First output test pads  410  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first output test pads  410  may be respectively extended to the first output pads  210 . The first output pads  210  and the first output test pads  410  may be respectively extended to each other by first output extending wires  610 . Second output test pads  420  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The second output test pads  420  may be respectively extended to the second output pads  220 . The second output pads  220  and the second output test pads  420  may be respectively extended to each other by second output extending wires  620 . The first output test pads  410  and the second output test pads  420  may be symmetrical (or substantially symmetrical) to each other with reference to an imaginary line IL that may be located or disposed between the first output test pads  410  and the second output test pads  420  in the flexible printed circuit pad area FCP. The imaginary line IL may extend approximately in a vertical direction, and may be located or disposed at a center of the flexible printed circuit pad area FCP. Thus, the first output test pads  410  may be located or disposed at the left side of the imaginary line IL, and the second output test pads  420  may be located or disposed at the right side of the imaginary line IL. However, the disclosure is not limited thereto. The flexible printed circuit pad area FCP may be horizontally symmetric (or substantially symmetric in horizontal). However, this is just an example, and an area where at least a part of the flexible printed circuit pad area FCP is not symmetrical may exist. 
     The first output test pads  410  and the second output test pads  420  may be linearly (or substantially linearly) arranged. The first output test pads  410  and the second output test pads  420  may extend in a direction that may be perpendicular to the imaginary line IL, for example, approximately in a horizontal direction. The first output test pads  410  and the second output test pads  420  may be located or disposed to be adjacent to the first input pads  310  and the second input pads  320 . The first input pads  310  may be located or disposed between the f first output pads  210  and the first output test pads  410 . As an example, the second input pads  320  may be located or disposed between the second output pads  220  and the second output test pads  420 . 
     First input test pads  510  may be located or disposed in the test pad area TP of the display panel  100 . The first input test pads  510  may be respectively extended to the first input pads  310 . The first input pads  310  and the first input test pads  510  may be respectively extended by first input extending wires  710 . Second input test pads  520  may be located or disposed in the test pad area TP of the display panel  100 . The second input test pads  520  may be respectively extended to the second input pads  320 . The second input pads  320  and the second input test pads  520  may be respectively extended by second input extending wires  720 . In the test pad area TP, the first input test pads  510  and the second input test pads  520  may be symmetrical (or substantially symmetrical) to each other with respect to an imaginary line IL located or disposed between the first input test pads  510  and the second input test pads  520 . The imaginary line IL may substantially extend in a perpendicular direction, and may be located or disposed at a center of the test pad area TP. Thus, the first input test pads  510  may be located or disposed at the left side of the imaginary line IL, and the second input test pads  520  may be located or disposed at the right side of the imaginary line IL. However, the disclosure is not limited thereto. The test pad area TP may be horizontally symmetric (or substantially symmetric in horizontal). However, this is just an example, and an area where at least a part of the test pad area TP is not symmetrical may exist. 
     The first input test pads  510  and the second input test pads  520  may be linearly (or substantially linearly) arranged. The first input test pads  510  and the second input test pads  520  may extend in a direction that may be perpendicular to the imaginary line IL, for example, approximately in a horizontal direction. The first input test pads  510  and the second input test pads  520  may be located or disposed to be adjacent to the first output test pads  410  and the second test output pads  420 . The first input test pads  510  and the second input test pads  520  may be located or disposed at an edge of or periphery of the display panel  100 . A cutting line CL may be located or disposed between the first output test pads  410  and the first input test pads  510 . Similarly, a cutting line CL may be located or disposed between the second output test pads  420  and the second input test pads  520 . Thus, the first input test pads  510  and the second input test pads  520  may be removed by a cutting or separation or removal process. In case of the first input extending wires  710  that are respectively extended to the first input test pads  510  and the first input pads  310 , portions of the first input extending wires  710  may be located or disposed in the driver IC pad area ICP, portions may be located or disposed in the flexible printed circuit pad area FCP, and the remainder may be located or disposed in the test pad area TP. Similarly, the second input extending wires  720  that are respectively extended to the second input test pads  520  and the second input pads  320 , portions of the second input extending wires  720  may be located or disposed in the driver IC pad area ICP, other portions may be located or disposed in the flexible printed circuit pad area FCP, and the remainder may be located or disposed in the test pad area TP. Thus, a portion of the first input extending wires  710  located or disposed in the test pad area TP and a portion of the second input extending wires  720  located or disposed in the test pad area TP may be removed by a cutting process or other separation or removal process. 
     Portions of the first input extending wires  710  may be located or disposed between the first output test pads  410 . Portions of the second input extending wires  720  may be located or disposed between the second output test pads  420 . 
     As shown in  FIG. 3  to  FIG. 5 , the first input pads  310 , the second input pads  320 , the first output pads  210 , and the second output pads  220  may be located or disposed in the driver IC pad area ICP of the display panel  100 . The first input pads  310 , the second input pads  320 , the first output pads  210 , and the second output pads  220  may be respectively formed in the shape of a parallelogram. However, this is merely an example, and the planar shape of the first input pads  310 , the second input pads  320 , the first output pads  210 , and the second output pads  220  may vary. For example, the first input pads  310 , the second input pads  320 , the first output pads  210 , and the second output pads  220  may be formed in a rectangular shape. 
     The first output test pads  410  and the second output test pads  420  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first output test pads  410  and the second output test pads  420  may be respectively formed in the shape of a parallelogram. However, this is just one example, and the planar shape of the first output test pads  410  and the second output test pads  420  may be variously changed. For example, the first output test pads  410  and the second output test pads  420  may have a rectangular shape. It is to be understood that the shapes of the various pads are not limited to that which is illustrated and may include any shapes within the spirit and the scope of the disclosure. 
     The first output pads  210  and the first output test pads  410  may be extended to each other by the first output extending wires  610 . Hereinafter, the first output pads  210 , the first output test pads  410 , and a connection portion of the first output pads  210  and the first output test pads  410  will be described. 
     A buffer layer  120  may be located or disposed on a buffer substrate  110 . The buffer layer  120  may be formed of a single layer of a silicon nitride (SiNx) or a multilayer structure in which a silicon nitride (SiNx) and a silicon oxide (SiOx) may be stacked. The buffer layer  120  may serve to planarize the surface of the substrate  110  while preventing penetration of unnecessary components such as impurities or moisture. 
     For clarity and ease of description, a single first output pad  210  and a single first output extending wire  610  and other elements in singular form are described with reference to  FIG. 4 . The first output pad  210  may be located or disposed on the buffer layer  120 . The first output extending wire  610  extended from the first output pad  210  may be located or disposed on the buffer layer  120 . The first output extending wire  610  may be branched from the first output pad  210  to the flexible printed circuit pad region FCP, while bypassing the first input pad  310  as illustrated in  FIG. 3 . The first output extending wire  610  may be in the form of a zigzag shape. 
     An insulation layer  140  may be located or disposed on the buffer layer  120 , the first output pad  210 , and the first output extending wire  610 . The insulating layer  140  may include an inorganic insulating material or an organic insulating material such as a silicon oxide (SiOx), a silicon nitride (SiNx), a silicon oxynitride (SiOxNy), fluorinated silicon oxide (SiOF), an aluminum oxide (AlOx), and the like, and may be formed of a single layer or multiple layers containing at least one of these materials. The insulation layer  140  may include a contact hole  142  that may overlap at least a part of the first output extending wire  610 . The first output test pad  410  may be located or disposed on the insulation layer  140 . The first output test pad  410  may be connected with the first output extending wire  610  through the contact hole  142 . 
     A passivation layer  160  may be located or disposed on the insulation layer  140  and the first output test pad  410 . The passivation layer  160  may include an inorganic insulating material or an organic insulating material, such as a silicon oxide (SiOx), a silicon nitride (SiNx), silicon oxynitride (SiOxNy), silicon fluoride (SiOF), an aluminum oxide (AlOx), and the like, and may be a single layer or multiple layers containing at least one of these materials. The passivation layer  160  may include an opening  162  that overlaps at least a part of the first output pad  210 . At least a part of the first output pad  210  may be exposed by the opening  162 . The passivation layer  160  may include an opening  164  that overlaps at least a part of the first output test pad  410 . At least a part of the first output test pad  410  may be exposed by the opening  164 . 
     The first output pad  210 , the first output test pad  410 , and the first output extending wire  610  are respectively illustrated as single layers, but the embodiment is not limited thereto. The first output pad  210 , the first output test pad  410 , and the first output extending wire  610  may be formed of multiple layers. 
     The second output pad  220  and the second output test pad  420  may be extended by the second output extending wire  620 . The second output extending wire  620  may be branched from the second output pad  220  to the flexible printed circuit pad area FCP, while bypassing the second input pad  320  as illustrated in  FIG. 3 . The second output extending wire  620  may be in the form of a zigzag shape. The second output test pad  420  and the second output extending wire  620  may be located or disposed on different layers, while disposing the insulation layer  140  therebetween, and may be connected with each other through a contact hole  152 . 
     First input test pads  510  and second input test pads  520  may be located or disposed in the test pad area TP of the display panel  100 . The first input test pads  510  and the second input test pads  520  may be respectively formed in the shape of a rectangle. However, this is merely an example, and a planar shape of the first input test pads  510  and the second input test pads  520  may be variously changed within the spirt and the scope of the disclosure. For example, the first input test pads  510  and the second input test pads  520  may be formed in the shape of a parallelogram. 
     The first input pads  310  and the first input test pads  510  may be extended by the first input extending wire  710 . The first input extending wire  710  may include a first portion  712 , a second portion  714 , and a third portion  716 . The first portion  712 , the second portion  714 , and the third portion  716  may be in a zigzag shape. 
     The second portion  714  of the first input extending wire  710  may be located or disposed on the buffer layer  120 . The second portion  714  of the first input extending wire  710  may be located or disposed in the flexible printed circuit pad area FCP. The second portion  714  of the first input extending wire  710  may be located or disposed between the first output test pads  410  in the flexible printed circuit pad area FCP. 
     The insulation layer  140  may be located or disposed on the buffer layer  120  and the second portion  714  of the first input extending wire  710 . The insulation layer  140  may include contact holes  144  and  146  that overlap at least a part of the second portion  714  of the first input extending wire  710 . The contact holes  144  and  146  may overlap, by way of example, opposite ends of the second portion  714  of the first input extending wire  710 . The first input pad  310  and the first portion  712  of the first input extending wire  710 , may extend from the first input pad  310 , may be located or disposed on the insulation layer  140 . The first portion  712  of the first input extending wire  710  may be located or disposed between the driver IC pad area ICP and the flexible printed circuit pad area FCP. The first input test pad  510  and the third portion  716  of the first input extending wire  710 , may extend from the first input test pad  510 , may be located or disposed on the insulation layer  140 . The third portion  716  of the first input extending wire  710  may be located or disposed between the flexible printed circuit pad area FCP and the test pad area TP. The first portion  712  of the first input extending wire  710  may be connected with the second portion  714  of the first input extending wire  710  through the contact hole  144 . The third portion  716  of the first input extending wire  710  may be connected with the second portion  714  of the first input extending wire  710  through the contact hole  146 . For example, one end of the second portion  714  of the first input extending wire  710  may be connected with the first portion  712 , and the other end thereof may be connected with the third portion  716 . 
     The passivation layer  160  may be located or disposed on the insulation layer  140  and the first input extending wire  710 . The passivation layer  160  may include an opening  166  that overlaps at least a part of the first input pad  310 . At least a part of the first input pad  310  may be exposed by the opening  166 . The passivation layer  160  may include an opening  168  that overlaps at least a part of the first input test pad  510 . At least a part of the first input test pad  510  may be exposed by the opening  168 . 
     The first input pad  310 , the first input test pad  510 , and the first input extending wire  710  are respectively illustrated as single layers, but the embodiment is not limited thereto. The first input pad  310 , the first input test pad  510 , and the first input extending wire  710  may be formed of multiple layers. 
     The second input pad  320  and the second input test pad  520  may be extended by the second input extending wire  720 . The second input extending wire  720  may include a first portion  722 , a second portion  724 , and a third portion  726 . The first portion  722  of the second input extending wire  720  may be branched from the second input pad  320  and thus may extends towards the flexible printed circuit pad area FCP. The third portion  726  of the second input extending wire  720  may be branched from the second input test pad  520  and thus may extend towards a portion adjacent to the flexible printed circuit pad area FCP. The second portion  724  of the second input extending wire  720  may connect the first portion  722  and the third portion  726 . The second portion  724  of the second input extending wire  720  may be located or disposed in a layer that is different from that of the first portion  722  and the third portion  726 , while disposing the insulation layer  140  therebetween. The first portion  722  of the second input extending wire  720  and the second portion  724  may be connected with each other through a contact hole  154  of the insulation layer  140 . The second portion  724  of the second input extending wire  720  and the third portion  726  may be connected with each other through a contact hole  156  of the insulation layer  140 . 
     Referring to  FIG. 6  to  FIG. 8 , the display device in a state after bonding the driver IC to the display device according to an embodiment will be described. 
       FIG. 6  is a top plan view of the display device according to an embodiment,  FIG. 7  is a block diagram of an area of the display device according to an embodiment, and  FIG. 8  is a top plan view of the area shown in  FIG. 7 . 
     As shown in  FIG. 6  to  FIG. 8 , a driver IC  900  may be located or disposed on the peripheral area PA of the display panel  100 . The driver IC  900  may be located or disposed in the driver IC pad area ICP. The driver IC  900  may include first output bumps  910  and second output bumps  920 . The first output bumps  910  of the driver IC  900  may overlap the first output pads  210 . The first output bumps  910  and the first output pads  210  may be electrically connected with each other. The second output bumps  920  of the driver IC  900  may overlap the second output pads  220 . The second output bumps  920  and the second output pads  220  may be electrically connected with each other. The driver IC  900  may include first input bumps  930  and second input bumps  940 . The first input bumps  930  of the driver IC  900  may overlap the first input pads  310 . The first input bumps  930  and the first input pads  310  may be electrically connected with each other. The second input bumps  940  of the driver IC  900  may overlap the second input pads  320 . The second input bumps  940  and the second input pads  320  may be electrically connected with each other. 
     The driver IC  900  and the display panel  100  may be electrically connected with the first output bumps  910 , the second output bumps  920 , the first input bumps  930 , and the second input bumps  940  of the driver IC  900  by the first output pads  210 , the second output pads  220 , the first input pads  310 , and the second input pads  320  of the display panel  100 . The display panel  100  may receive a predetermined signal from the driver IC  900 . When the bonding between the display panel  100  and the driving integrated circuit  900  is not properly performed, the driving of the display panel  100  may be adversely affected. Therefore, testing may take place to determine whether bonding between the display panel  100  and the driving integrated circuit  900  is properly performed by measuring the bonding resistance between the display panel  100  and the driving integrated circuit  900 . 
     For example, the bonding resistance between the first output pads  210  and the first output bumps  910  may be measured by applying a predetermined signal to the first output test pads  410  connected with the first output pads  210 . Bonding resistance between the second output pads  220  and the second output bumps  920  may be measured by applying a predetermined signal to the second output test pads  420  connected with the second output pads  220 . Bonding resistance between the first input pads  310  and the first input bumps  930  may be measured by applying a predetermined signal to the first input test pads  510  connected with the first input pads  310 . Bonding resistance between the second input pads  320  and the second input bumps  940  may be measured by applying a predetermined signal to the second input test pads  520  connected with the second input pads  320 . 
     The disclosure is not limited to only pads for testing bonding resistance. Other pads that may be suitable for various other tests may be provided on the test pad area TP within the spirit and the scope of the disclosure. After a test is finished, a cutting process or other separation or removal process for removing the test pad area TP may be carried out. Hereinafter, the display device in a state after the cutting process according to an embodiment will be described with reference to  FIG. 9  to  FIG. 11 . 
       FIG. 9  is a top plan view of the display device according to an embodiment,  FIG. 10  is a block diagram of an area of the display device according to an embodiment, and  FIG. 11  is a top plan view of the area shown in  FIG. 10 . 
     As shown in  FIG. 9  to  FIG. 11 , portions located or disposed in a lower portion of the display panel  100  with reference to the cutting line CL may be removed, and portions disposed on an upper portion of the display panel  100  may remain. Since the test pad area TP is removed, the first input test pad  510  and the second input test pad  520  located or disposed in the test pad area TP may be removed. A part of the first input extending wires  710  may be removed, and a part may remain. The remaining portions of the first input extending wires  710  may be located or disposed between the first output test pads  410 . Similarly, a part of the second input extending wires  720  may be removed, and a part may remain. The remaining portions of the second input extending wires  720  may be located or disposed between the second output test pads  420 . 
     In an embodiment, components that may be necessary for the bonding resistance test of the driver IC  900  may be located or disposed in the test pad area TP, thereby increasing the utilization of the space of the peripheral area PA of the display panel  100 . When the first output test pad  410 , the second output test pad  420 , the first input test pad  510 , and the second input test pad  520 , which are components that may be required for the bonding resistance test of the driver IC  900 , are all located in the flexible printed circuit pad area FCP, the density of the flexible printed circuit pad area FCP may be increased, and there may be a limit in reducing the width of the peripheral area PA. In an embodiment, the first input test pad  510  and the second input test pad  520  may be located or disposed in the test pad area TP, and after the bonding resistance test is finished, the test pad area TP may be removed by performing a cutting, separation, or removal process so that the density of the flexible printed circuit pad area FCP may be lowered and the width of the peripheral area PA may be further reduced. 
     The first input test pad  510 , which may be an element required for the bonding resistance test, may be placed in the test pad area TP instead of the flexible printed circuit pad area FCP, and thus the first input extending wires  710  connected with the first input test pad  510  may pass between first output test pads  410 . As the second input test pad  520 , which may be an element required for the bonding resistance test, may be placed in the test pad area TP instead of the flexible printed circuit pad area FCP, the second input extending wires  720  connected with the second input test pad  520  may pass between the second output test pads  420 . 
     The display device in a state after bonding the flexible printed circuit thereto according to an embodiment will be described with reference to  FIG. 12  to  FIG. 15 . 
       FIG. 12  is a top plan view of the display device according to an embodiment,  FIG. 13  is a block diagram of an area of the display device according to an embodiment, and  FIG. 14  is a top plan view of the area shown in  FIG. 13 .  FIG. 15  is a schematic cross-sectional view of  FIG. 14 , taken along the line XV-XV. 
     As shown in  FIG. 12  to  FIG. 15 , a flexible printed circuit  950  may be located or disposed on the peripheral area PA of the display panel  100 . The flexible printed circuit  950  may be located or disposed in the flexible printed circuit pad area FCP. An anisotropic conductive film (ACF)  990 , which may have conductivity only in a thickness direction, may be located or disposed between the substrate  110  of the display panel  100  and the flexible printed circuit  950 . The flexible printed circuit  950  may include first test bumps  960  and second test bumps  970 . The first test bumps  960  of the flexible printed circuit  950  may overlap the first output test pads  410 . The first test bumps  960  and the first output test pads  410  may be electrically connected with each other. The second test bumps  970  of the flexible printed circuit  950  may overlap the second output test pads  420 . The second test bumps  970  and the second output test pads  420  may be electrically connected with each other. 
     The flexible printed circuit  950  and the display panel  100  may be electrically connected with each other by the first test bumps  960  and the second test bumps  970  of the flexible printed circuit  950  and the first output test pads  410  and the second output test pads  420  of the display panel  100 . The display panel  100  may receive a predetermined signal from the flexible printed circuit  950 . The first output test pads  410  and the second output test pads  420  may be applied with a constant voltage. 
     The first input extending wires  710  may have already been partially removed by the cutting, separation, or removal process. For example, cut, or separated, or removed portions of the first input extending wires  710  may be exposed, thereby electrically affecting the display panel  100 . In an embodiment, a finish member  995  may be located or disposed to cover a bottom or lower surface and a side surface of an edge of the display panel  100  and a bottom or lower surface of the flexible printed circuit  950 . The finish member  995  may be formed of a material such as a resin and the like. Since the finish member  995  may be located or disposed to cover the first input extending wires  710 , occurrence of electrical influence due to the exposure of the first input extending wires  710  may be prevented. 
     A display device according to an embodiment will be described with reference to  FIG. 16  and  FIG. 17 . 
     The display device according to an embodiment shown in  FIG. 16  and  FIG. 17  may be similar to the display device according to an embodiment shown in  FIG. 1  to  FIG. 15 , and therefore a description of the same parts will be omitted. In an embodiment, positions of the second output test pad  420  and the second input test pad  520  may be different from those of an embodiment, which will be further described below. 
       FIG. 16  is a block diagram of an area of a display device according to an embodiment.  FIG. 16  shows the display device in a state before bonding a driver IC to the display device according to an embodiment.  FIG. 17  is a block diagram of an area of a display device according to an embodiment.  FIG. 17  shows a state in which a cutting, separation, or removal process of the display device according to an embodiment may be performed and then a flexible printed circuit may be bonded to the display device.  FIG. 16  and  FIG. 17  show peripheral areas of the display panels. 
     As shown in  FIG. 16 , a display panel  100  may include a driver IC pad area ICP, a flexible printed circuit pad area FCP, and a test pad area TP. A cutting line CL may be located or disposed between the flexible printed circuit pad area FCP and the test pad area TP. 
     First input pads  310  and first output pads  210  may be located or disposed in the driver IC pad area ICP of the display panel  100 . Second input pads  320  and second output pads  220  may be provided in the driver IC pad area ICP of the display panel  100 . 
     First output test pads  410  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first output pads  210  and the first output test pads  410  may be extended by first output extending wires  610 . Second input test pads  520  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The second input pads  320  and the second input test pads  520  may be respectively extended by second input extending wires  720 . The first output test pads  410  and the second input test pads  520  may be linearly (or substantially linearly) arranged. However, the disclosure is not limited thereto. 
     First input test pads  510  may be located or disposed in the test pad area TP of the display panel  100 . The first input pads  310  and the first input test pads  510  may be respectively extended by the first input extending wires  710 . Second output test pads  420  may be located or disposed in the test pad area TP of the display panel  100 . The second output pads  220  and the second output test pads  420  may be respectively extended by second output extending wires  620 . The first input test pads  510  and the second output test pads  420  may be linearly (or substantially linearly) arranged. However, the disclosure is not limited thereto. 
     In an embodiment, the first input test pad  510  and the second input test pad  520 , which may be components that may be necessary for a bonding resistance test, may be positioned in the test pad area TP so that the density of the flexible printed circuit pad area FCP may be lowered and the width of the peripheral area may be further reduced. 
     As described, the first input test pad  510  may be placed in the test pad area TP instead of the flexible printed circuit pad area FCP, and thus the first input extending wires  710  connected with the first input test pad  510  may pass between output test pads  410 . For example, the first input extending wires s  710  may be located or disposed between the first output test pads  410 . As the second output test pad  420 , which may be an element that may be required for the bonding resistance test, may be placed in the test pad area TP instead of the flexible printed circuit pad area FCP, the second output extending wires  620  connected with the second output test pad  420  may pass between the second input test pads  520 . For example, the second output extending wires  620  may be located or disposed between the second input test pads  520 . 
     As shown in  FIG. 17 , after the cutting or separation or removal process, the test pad area TP of the display panel  100  may be removed. Accordingly, the first input test pads  510  and the second output test pads  420  located or disposed in the test pad area TP may be removed. 
     A driver IC  900  may be located or disposed in the driver IC pad area ICP of the display panel  100 . First output bumps  910  of the driver IC  900  may be electrically connected with the first output pads  210 . Second output bumps  920  of the driver IC  900  may be electrically connected with the second output pads  220 . A first input bump  930  of the driver IC  900 , for example, may be electrically connected with the first input pad  310 . A second input bump  940  of the driver IC  900 , for example, may be electrically connected with the second input pad  320 . 
     A flexible printed circuit  950  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first test bumps  960  of the flexible printed circuit  950  may overlap the first output test pads  410 . The first test bumps  960  and the first output test pads  410  may be electrically connected with each other. The second test bumps  970  of the flexible printed circuit  950  may overlap the second input test pads  520 . The second test bumps  970  and the second input test pads  520  may be electrically connected with each other. The first output test pads  410  and the second input test pads  520  may be applied with a constant voltage. 
     A display device according to an embodiment will be described with reference to  FIG. 18  and  FIG. 19 . 
     The display device according to an embodiment shown in  FIG. 18  and  FIG. 19  may be similar to the display device according to an embodiment shown in  FIG. 1  to  FIG. 15 , and therefore a description of the same parts will be omitted. In an embodiment, positions of the first output test pad  410 , the second output test pad  420 , the first input test pad  510 , and the second input test pad  520  may be different from those of the previous embodiment, and will be further described below. 
       FIG. 18  is a block diagram of an area of a display device according to an embodiment.  FIG. 18  shows the display device in a state before bonding a driver IC to the display device according to an embodiment.  FIG. 19  is a block diagram of an area of a display device according to an embodiment.  FIG. 19  shows a state in which a cutting or separation or removal process of the display device according to an embodiment is performed and then a flexible printed circuit is bonded to the display device.  FIG. 18  and  FIG. 19  show peripheral areas of the display panels. 
     As shown in  FIG. 18 , a display panel  100  may include a driver IC pad area ICP, a flexible printed circuit pad area FCP, and a test pad area TP. A cutting line CL may be located or disposed between the flexible printed circuit pad area FCP and the test pad area TP. 
     First input pads  310  and first output pads  210  may be located or disposed in the driver IC pad area ICP of the display panel  100 . Second input pads  320  and second output pads  220  may be located or disposed in the driver IC pad area ICP of the display panel  100 . 
     First input test pads  510  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first input pads  310  and the first input test pads  510  may be extended by first input extending wires  710 . Second input test pads  520  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The second input pads  320  and the second input test pads  520  may be respectively extended by second input extending wires  720 . First input test pads  510  and second input test pads  520  may be linearly (or substantially linearly) located or disposed. 
     First output test pads  410  may be located or disposed in the test pad area TP of the display panel  100 . The first output pads  210  and the first output test pads  410  may be extended by the first output extending wires  610 . Second output test pads  420  may be located or disposed in the test pad area TP of the display panel  100 . The second output pads  220  and the second output test pads  420  may be respectively extended by second output extending wires  620 . The first output test pads  410  and the second output test pads  420  may be linearly (or substantially linearly) located or disposed. 
     In an embodiment, the first output test pads  410  and the second output test pads  420 , which may be elements necessary for a bonding resistance test, may be positioned or located or disposed in the test pad area TP so that the density of the flexible printed circuit pad area FCP may be lowered and the width of the peripheral area may be further reduced. 
     As described, the first output test pads  410  may be placed in the test pad area TP instead of the flexible printed circuit pad area FCP, and thus the first output extending wires  610  connected with the first output test pads  410  may pass between the first input test pads  510 . For example, the first output extending wires  610  may be located or disposed between the first input test pads  510 . For example, as the second output test pads  420 , which may be an element required for the bonding resistance test, is placed in the test pad area TP instead of the flexible printed circuit pad area FCP, the second output extending wires  620  connected with the second output test pads  420  may pass between the second input test pads  520 . For example, the second output extending wires  620  may be located or disposed between the second input test pads  520 . 
     As shown in  FIG. 19 , after a cutting or separation or removal process, the test pad area TP of the display panel  100  may be removed. Thus, the first output test pads  410  and the second output test pads  420  may be removed in the test pad area TP. 
     A driver IC  900  may be located or disposed in the driver IC pad area ICP of the display panel  100 . First output bumps  910  of the driver IC  900  may be electrically connected with the first output pads  210 . Second output bumps  920  of the driver IC  900  may be electrically connected with the second output pads  220 . First input bumps  930  of the driver IC  900  may be electrically connected with the first input pads  310 . Second input bumps  940  of the driver IC  900  may be electrically connected with the second input pads  320 . 
     A flexible printed circuit  950  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . First test bumps  960  of the flexible printed circuit  950  may overlap the first input test pads  510 . The first test bumps  960  and the first input test pads  510  may be electrically connected with each other. Second test bumps  970  of the flexible printed circuit  950  may overlap the second input test pads  520 . The second test bumps  970  and the second input test pads  520  may be electrically connected with each other. The first input test pads  510  and the second input test pads  520  may be applied with a constant voltage. 
     A display device according to an embodiment will be described with reference to  FIG. 20  and  FIG. 21 . 
     The display device according to the embodiment shown in  FIG. 20  and  FIG. 21  may be similar to the display device according to an embodiment shown in  FIG. 1  to  FIG. 15 , and therefore a description of the same parts will be omitted. In an embodiment, positions of the first output test pads  410  and the first input test pads  510  may be different from those of an embodiment, which will be described below. 
       FIG. 20  is a block diagram of an area of a display device according to an embodiment.  FIG. 20  shows the display device in a state before bonding a driver IC to the display device according to an embodiment.  FIG. 21  is a block diagram of an area of a display device according to an embodiment.  FIG. 21  shows a state in which a cutting or separation or removal process of the display device according to an embodiment may be performed and then a flexible printed circuit may be bonded to the display device.  FIG. 20  and  FIG. 21  show peripheral areas of the display panels. 
     As shown in  FIG. 20 , a display panel  100  may include a driver IC pad area ICP, a flexible printed circuit pad area FCP, and a test pad area TP. A cutting line CL may be located or disposed between the flexible printed circuit pad area FCP and the test pad area TP. 
     First input pads  310  and first output pads  210  may be located or disposed in the driver IC pad area ICP of the display panel  100 . For example, second input pads  320  and second output pads  220  may be located or disposed in the driver IC pad area ICP of the display panel  100 . 
     First input test pads  510  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first input pads  310  and the first input test pads  510  may be respectively extended by first input extending wires  710 . Second output test pads  420  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The second output pads  220  and the second output test pads  420  may be respectively extended by second output extending wires  620 . The first input test pads  510  and the second output test pads  420  may be linearly (or substantially linearly) arranged. 
     First output test pads  410  may be located or disposed in the test pad area TP of the display panel  100 . The first output pads  210  and the first output test pads  410  may be respectively extended by first output extending wires  610 . Second input test pads  520  may be located or disposed in the test pad area TP of the display panel  100 . The second input pads  320  and the second input test pads  520  may be respectively extended by second input extending wires  720 . The first output test pads  410  and the second input test pads  520  may be linearly (or substantially linearly) arranged. 
     In an embodiment, the first output test pads  410  and the second input test pads  520 , which may be elements necessary for a bonding resistance test, may be positioned or located or disposed in the test pad area TP so that the density of the flexible printed circuit pad area FCP may be lowered and the width of the peripheral area may be further reduced. 
     As described, the first output test pads  410  may be placed in the test pad area TP instead of the flexible printed circuit pad area FCP, and thus the first output extending wires  610  connected with the first output test pads  410  may pass between the first input test pads  510 . For example, the first output extending wires  610  may be located or disposed between the first input test pads  510 . For example, as the second input test pads  520 , which may be elements required for the bonding resistance test, is placed in the test pad area TP instead of the flexible printed circuit pad area FCP, the second input extending wires  720  connected with the second input test pads  520  may pass between the second output test pads  420 . For example, the second input extending wires  720  may be located or disposed between the second output test pads  420 . 
     As shown in  FIG. 21 , after the cutting or separation or removal process, the test pad area PT of the display panel  100  may be removed. Accordingly, the first output test pads  410  and the second input test pads  520  located or disposed in the test pad area TP may be removed. 
     A driver IC  900  may be located or disposed in the driver IC pad area ICP of the display panel  100 . First output bumps  910  of the driver IC  900  may be electrically connected with the first output pads  210 . Second output bumps  920  of the driver IC  900  may be electrically connected with the second output pads  220 . First input bumps  930  of the driver IC  900  may be electrically connected with the first input pads  310 . Second input bumps  940  of the driver IC  900  may be electrically connected with the second input pads  320 . 
     A flexible printed circuit  950  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first test bumps  960  of the flexible printed circuit  950  may overlap the first input test pads  510 . The first test bumps  960  and the first input test pads  510  may be electrically connected with each other. The second test bumps  970  of the flexible printed circuit  950  may overlap the second output test pads  420 . The second test bumps  970  and the second output test pads  420  may be electrically connected with each other. The first input test pads  510  and the second output test pads  420  may be applied with a constant voltage. 
     A display device according to an embodiment will be described with reference to  FIG. 22  and  FIG. 23 . 
     The display device according to an embodiment shown in  FIG. 22  and  FIG. 23  may be similar to the display device according to an embodiment shown in  FIG. 20  and  FIG. 21 , and therefore a description of the same parts will be omitted. An embodiment may be different from the previous embodiment in that the bonding resistance measuring pad may not be located or disposed in the test pad region, which will be described below. 
       FIG. 22  is a block diagram of an area of a display device according to an embodiment.  FIG. 22  shows the display device in a state before bonding a driver IC to the display device according to an embodiment.  FIG. 23  is a block diagram of an area of a display device according to an embodiment.  FIG. 23  shows a state in which a cutting or separation or removal process of the display device according to an embodiment may be performed and then a flexible printed circuit may be bonded to the display device.  FIG. 22  and  FIG. 23  show peripheral areas of the display panels. 
     As shown in  FIG. 22 , a display panel  100  may include a driver IC pad area ICP, a flexible printed circuit pad area FCP, and a test pad area TP. A cutting line CL may be located or disposed between the flexible printed circuit pad area FCP and the test pad area TP. 
     First input pads  310  and second output pads  220  may be located or disposed in the driver IC pad area ICP of the display panel  100 . In an embodiment, there may be no elements corresponding to the second input pads  320  and the first output pads  210  as in the previous embodiment. 
     First input test pads  510  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first input pads  310  and the first input test pads  510  may be respectively extended by first input extending wires  710 . Second output test pads  420  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The second output pads  220  and the second output test pads  420  may be respectively extended by second output extending wires  620 . The first input test pads  510  and the second output test pads  420  may be linearly (or substantially linearly) arranged. 
     In an embodiment, a pad for measuring bonding resistance may not be located or disposed in the test pad area TP of the display panel  100 . By way of example, in an embodiment, there may be no elements corresponding to the second input extending wires  720  and the first output extending wires  610  as in an embodiment. 
     In an embodiment, the density of the flexible printed circuit pad area FCP may be reduced, and the width of the peripheral area may be further reduced by omitting elements corresponding to the second input pads  320 , the second input extending wires  720 , the first output pads  210 , and the first output extending wires  610 . 
     As shown in  FIG. 23 , after the cutting or separation or removal process, the test pad area TP of the display panel  100  may be removed. 
     A driver IC  900  may be located or disposed in the driver IC pad area ICP of the display panel  100 . Second output bumps  920  of the driver IC  900  may be electrically connected with the second output pads  220 . First input bumps  930  of the driver IC  900  may be electrically connected with the first input pads  310 . 
     A flexible printed circuit  950  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first test bumps  960  of the flexible printed circuit  950  may overlap the first input test pads  510 . The first test bumps  960  and the first input test pads  510  may be electrically connected with each other. The second test bumps  970  of the flexible printed circuit  950  may overlap the second output test pads  420 . The second test bumps  970  and the second output test pads  420  may be electrically connected with each other. The first input test pads  510  and the second output test pads  420  may be applied with a constant voltage. 
     A display device according to an embodiment will be described with reference to  FIG. 24  and  FIG. 25 . 
     The display device according to an embodiment shown in  FIG. 24  and  FIG. 25  may be similar to the display device according to an embodiment shown in  FIG. 16  to  FIG. 17 , and therefore a description of the same parts will be omitted. The embodiment may be different from the previous embodiment in that the bonding resistance measuring pad may not be located or disposed in the test pad region, which will be described below. 
       FIG. 24  is a block diagram of an area of a display device according to an embodiment.  FIG. 24  shows the display device in a state before bonding a driver IC to the display device according to an embodiment.  FIG. 25  is a block diagram of an area of a display device according to an embodiment.  FIG. 25  shows a state in which a cutting or separation or removal process of the display device according to an embodiment may be performed and then a flexible printed circuit may be bonded to the display device.  FIG. 24  and  FIG. 25  show peripheral areas of the display panels. 
     As shown in  FIG. 24 , a display panel  100  may include a driver IC pad area ICP, a flexible printed circuit pad area FCP, and a test pad area TP. A cutting line CL may be located or disposed between the flexible printed circuit pad area FCP and the test pad area TP. 
     First output pads  210  and second input pads  320  may be located or disposed in the driver IC pad area ICP of the display panel  100 . In an embodiment, there may be no elements corresponding to the second output pads  220  and the first input pads  310  as in the previous embodiment. 
     First output test pads  410  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The first output pads  210  and the first output test pads  410  may be respectively extended by first output extending wires  610 . Second input test pads  520  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . The second input pads  320  and the second input test pads  520  may be respectively extended by second input extending wires  720 . First output test pads  410  and second input test pads  520  may be linearly (or substantially linearly) arranged. 
     In an embodiment, a pad for measuring bonding resistance may not be located or disposed in the test pad area TP of the display panel  100 . For example, in an embodiment, there may be no elements corresponding to the second output extending wires  620  and the first input extending wires  710  as in an embodiment. 
     In an embodiment, the density of the flexible printed circuit pad area FCP may be reduced, and the width of the peripheral area may be further reduced by omitting elements corresponding to the second output pad  220 , the first input extending wires  710 , the first input pads  310 , and the first input extending wires  710 . 
     As shown in  FIG. 25 , after the cutting or separation or removal process, the test pad area TP of the display panel  100  may be removed. 
     A driver IC  900  may be located or disposed in the driver IC pad area ICP of the display panel  100 . First output bumps  910  of the driver IC  900  may be electrically connected with the first output pads  210 . Second input bumps  940  of the driver IC  900  may be electrically connected with the second input pads  320 . 
     A flexible printed circuit  950  may be located or disposed in the flexible printed circuit pad area FCP of the display panel  100 . First test bumps  960  of the flexible printed circuit  950  may overlap the first output test pads  410 . The first test bumps  960  and the first output test pads  410  may be electrically connected with each other. Second test bumps  970  of the flexible printed circuit  950  may overlap the second input test pads  520 . The second test bumps  970  and the second input test pads  520  may be electrically connected with each other. The first output test pads  410  and the second input test pads  520  may be applied with a constant voltage. 
     While this disclosure has been described in connection with the embodiments, it is to be understood that the disclosure is not limited to the disclosed embodiments. This disclosure is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the disclosure.