Display device

Abstract

An exemplary embodiment of the present application relates to a display device including a display panel or a substrate, a fingerprint sensor disposed on a first side of the display panel or the substrate and including a frame and a sensing portion disposed in the frame, and an adhesive bonding the fingerprint sensor to the display panel or the substrate by contacting an outer side of the frame and the first side of the display panel or the substrate, wherein a refractive pattern corresponding to a predetermined height of the adhesive is formed in the outer side of the frame, and a height of a portion of the adhesive contacting the frame is higher than or equal to a height of the refractive pattern.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to a display device. More particularly, the present application relates to a display device including a fingerprint sensor. BACKGROUND

[0002] Biometric technologies using personal security features for personal security systems are commercially available. Fingerprint recognition, iris recognition, face recognition, and vein recognition are examples of such biometric technologies.

[0003] Fingerprint recognition uses a fingerprint sensor that can recognize a fingerprint, such as a fingerprint of a human finger. The fingerprint sensor adopts an electrostatic method for recognizing an electric field flowing through a human body according to the curvature of a fingerprint, an optical method for acquiring a fingerprint image reflected by visible light, and an ultrasonic method for acquiring a fingerprint image using ultrasonic waves.

[0004] The fingerprint sensor is attached to a display device, such as a smartphone, and can be used for locking the display device and mobile payment.

[0005] The above information disclosed in this Background section is only for enhancing the understanding of the background of the application, and therefore, it can contain information that does not form the prior art that is already known in this country to those of ordinary skill in the art. SUMMARY

[0006] During a process for attaching a fingerprint sensor to a display device, an adhesive, such as resin, is applied to fix the fingerprint sensor to the display device. In order to fix the fingerprint sensor, the adhesive needs to be applied up to a predetermined height. When the adhesive is applied lower than the predetermined height, the adhesion of the fingerprint sensor can be weakened, and when the application of the adhesive is excessively higher than the predetermined height, the adhesive can be wasted. Therefore, in the process of attaching the fingerprint sensor to the display device, it should be checked whether the adhesive has been applied to the predetermined height. When the height of the adhesive is directly measured before the adhesive is cured, the fingerprint sensor can be touched, causing poor adhesion of the fingerprint sensor. In order to avoid touching the fingerprint sensor, a non-contact method, such as laser measurement, can be used, but it is not possible to measure the precise height of the adhesive due to light scattering from the display panel.

[0007] An object of the present application is to provide a display device that can easily test whether an adhesive is applied up to a predetermined height during a process for attaching a fingerprint sensor to a display device and enhance the adhesion of the fingerprint sensor.

[0008] A display device according to an exemplary embodiment of the present application includes a display panel; a fingerprint sensor disposed on a first side of the display panel and including a frame and a sensing portion disposed in the frame; and an adhesive joining the fingerprint sensor to the display panel by contacting an outer side of the frame and the first side of the display panel, wherein a refractive pattern corresponding to a predetermined height of the adhesive is formed in the outer side of the frame, and a height of a portion of the adhesive contacting the frame is higher than or equal to a height of the refractive pattern.

[0009] The refractive pattern can include a step formed in the outer side of the frame.

[0010] The height of the step can correspond to the predetermined height of the adhesive, the height of the step being a distance from the first side of the display panel to the step.

[0011] The height of the portion of the adhesive contacting the frame can be the same as or higher than the height of the step.

[0012] The refractive pattern can include an inclined side formed in the outer side of the frame.

[0013] The height of the inclined side can correspond to the predetermined height of the adhesive, the height of the inclined side being a distance from the first side of the display panel to a topmost portion of the inclined side.

[0014] The height of the portion of the adhesive contacting the frame can be the same as or higher than the height of the inclined side.

[0015] The refractive pattern can include a groove formed in the outer side of the frame.

[0016] The height of the groove can correspond to the predetermined height of the adhesive, the height of the groove being a distance from the first side of the display panel to a topmost portion of the groove.

[0017] The height of the portion of the adhesive contacting the frame can be the same as or higher than the height of the groove.

[0018] A display device according to another exemplary embodiment of the present application includes a display panel; a back substrate facing the display panel; a fingerprint sensor disposed on a first side of the back substrate and including a frame, a sensing portion disposed in the frame, and a base substrate connected to the sensing portion; and an adhesive joining the fingerprint sensor to the back substrate by contacting an outer side of the frame, a side surface of the base substrate, and the first side of the back substrate, wherein a refractive pattern corresponding to a predetermined height of the adhesive is formed in the outer side of the frame, and a height of a portion where the adhesive contacts the outer side of the frame and the side surface of the base substrate is higher than or equal to a height of the refractive pattern.

[0019] The refractive pattern can include a step formed in the outer side of the frame.

[0020] The height of the step can correspond to the predetermined height of the adhesive, the height of the step being a distance from a first side of the display panel to the step.

[0021] The height of the portion where the adhesive contacts the outer side of the frame and the side surface of the base substrate can be the same as or higher than the height of the step.

[0022] The refractive pattern can include an inclined side formed in the outer side of the frame.

[0023] The height of the inclined side can correspond to the predetermined height of the adhesive, the height of the inclined side being a distance from the first side of the display panel to a topmost portion of the inclined side.

[0024] The height of the portion where the adhesive contacts the outer side of the frame and the side surface of the base substrate can be the same as or higher than the height of the inclined side.

[0025] The refractive pattern can include a groove formed in the outer side of the frame.

[0026] The height of the groove can correspond to the predetermined height of the adhesive, the height of the groove being a distance from the first side of the display panel to a topmost portion of the groove.

[0027] The height of the portion where the adhesive contacts the outer side of the frame and the side surface of the base substrate can be the same as or higher than the height of the groove.

[0028] In the process of joining the fingerprint sensor to the display device, it is easy to test whether the adhesive has been applied up to the predetermined height, and by shortening the test time of the fingerprint sensor, it is possible to improve production efficiency. In addition, the adhesion of the fingerprint sensor can be enhanced. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a schematic top plan view of a display device including a fingerprint sensor according to an exemplary embodiment.

[0030] Figure 2 is a cross-sectional view of a state in which a fingerprint sensor is attached to a display panel according to an exemplary embodiment.

[0031] Figure 3 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a display panel according to an exemplary embodiment.

[0032] Figure 4 is a cross-sectional view of a state in which a fingerprint sensor is attached to a display panel according to another exemplary embodiment.

[0033] Figure 5 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a display panel according to an exemplary embodiment.

[0034] Figure 6 is a cross-sectional view of a state in which a fingerprint sensor is attached to a display panel according to another exemplary embodiment.

[0035] Figure 7 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a display panel according to an exemplary embodiment.

[0036] Figure 8 is a cross-sectional view of an example of an optical type fingerprint sensor.

[0037] Figure 9 is an exploded perspective view of a display device including a fingerprint sensor according to another exemplary embodiment.

[0038] Figure 10 is a cross-sectional view of an example of a state in which a fingerprint sensor is attached to a back substrate according to an exemplary embodiment.

[0039] Figure 11 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a back substrate according to an exemplary embodiment.

[0040] Figure 12 is a cross-sectional view of an example of a state in which a fingerprint sensor is attached to a back substrate according to another exemplary embodiment.

[0041] Figure 13is a cross-sectional view of another example of a state in which a fingerprint sensor according to an exemplary embodiment is attached to a rear substrate.

[0042] Figure 14 is a cross-sectional view of an example of a state in which a fingerprint sensor according to another exemplary embodiment is attached to a rear substrate.

[0043] Figure 15 is a cross-sectional view of another example of a state in which a fingerprint sensor according to an exemplary embodiment is attached to a rear substrate.

[0044] Figure 16 is a cross-sectional view of another example of an optical type fingerprint sensor. DETAILED DESCRIPTION

[0045] Hereinafter, embodiments of the present application will be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the application are shown. As those skilled in the art would realize, the described embodiments can be modified in various different ways, all without departing from the spirit or scope of the application.

[0046] Also, in the exemplary embodiments, since like reference numerals indicate like elements having the same configuration, the first exemplary embodiment is representatively described, and only the configuration different from the first exemplary embodiment will be described in other exemplary embodiments.

[0047] Portions unrelated to the description will be omitted to clearly describe the present application, and throughout the specification, the same or similar constituent elements will be indicated by the same reference numerals.

[0048] Since the size and thickness of each component shown in the drawings are arbitrarily shown for better understanding and easy description, the present application is not necessarily limited to what is shown. In the drawings, the thickness of layers, films, panels, regions, and the like is exaggerated for clarity. In addition, in the drawings, the thickness of some layers and regions is exaggerated for better understanding and easy description.

[0049] It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. In addition, when an element is referred to as being "on" or "over" another element, it can be positioned on, under, or in the other element and does not necessarily mean "on... or "over... in a direction opposite to gravitational force.

[0050] In addition, unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0051] Also, throughout the specification, the phrase "on a plane" refers to a case of observing a target portion from the top, and the phrase "cross section" refers to a case of observing a cross section of a target portion cut in a vertical direction from the side.

[0052] First, a display device according to an exemplary embodiment will be described with reference to Figure 1 and Figure 2 .

[0053] Figure 1 is a schematic plan view of a display device including a fingerprint sensor according to an exemplary embodiment. Figure 2 is a cross-sectional view of a state in which a fingerprint sensor is attached to a display panel according to an exemplary embodiment.

[0054] Referring to Figure 1 , the display device includes a display panel 100, a fingerprint sensor 200, and an adhesive 300.

[0055] The display panel 100 includes a plurality of pixels and displays an image. The display panel 100 can include a touch sensor including a plurality of touch electrodes to sense a contact touch or a non-contact touch of a user. The display panel 100 can be flexible or rigid. The display panel 100 includes a planar surface, and can partially include a curved surface. Hereinafter, the display panel 100 formed in a plane will be exemplarily described.

[0056] The fingerprint sensor 200 can be attached to a lower portion of the display panel 100 by the adhesive 300. In Figure 1 , the fingerprint sensor 200 is illustrated as a quadrilateral on a plane, but a planar shape of the fingerprint sensor 200 is not limited.

[0057] The adhesive 300 is disposed to surround the fingerprint sensor 200 on a plane, and thus can fix the fingerprint sensor 200 to the display panel 100. In Figure 1 , the adhesive 300 contacts the fingerprint sensor 200 by surrounding all sides of the fingerprint sensor 200, but depending on exemplary embodiments, the adhesive 300 can contact only a portion of the fingerprint sensor 200. For example, the adhesive 300 can be disposed to contact three sides or two sides of the fingerprint sensor 200 at the same time. As a non-limiting example, the adhesive 300 can include a resin in addition to an adhesive having a certain viscosity such as an optically clear resin (OCR), an optically clear adhesive (OCA), a liquid epoxy-based adhesive, and a liquid acrylic-based adhesive.

[0058] Referring to Figure 2The display panel 100 includes a first side 100a and a second side 100b, the second side 100b being an opposite side of the first side 100a. The first side 100a can be a rear side of the display panel 100, and the second side 100b can be a front side of the display panel 100 on which an image is displayed. The first side 100a is a side to which the fingerprint sensor 200 is attached, and the second side 100b can be a side on which an object such as a fingerprint is contacted. The fingerprint sensor 200 is disposed on the first side 100a of the display panel 100.

[0059] The fingerprint sensor 200 includes a frame 210, a sensing portion 220, and a base substrate 230. The frame 210 can have a structure that supports the sensing portion 220 by surrounding a side surface of the sensing portion 220. The sensing portion 220 is disposed inside the frame 210. The sensing portion 220 includes at least one constituent element capable of recognizing a fingerprint of an electrostatic type, an optical type, and an ultrasonic type, etc., and the constituent element of the sensing portion 220 is not limited. The base substrate 230 can be electrically connected with the sensing portion 220. For example, the base substrate 230 can include at least one constituent element that reads and / or controls a signal sensed by the sensing portion 220, and can include a printed circuit board (PCB) or a flexible printed circuit board (FPCB). The base substrate 230 can be disposed on the frame 210.

[0060] A height h2 of the frame 210 from the first side 100a of the display panel 100 can be higher than a height of the sensing portion 220, and an air layer AL can be disposed between the sensing portion 220 and the first side 100a of the display panel 100. The sensing portion 220 can be spaced apart from the display panel 100 by the air layer AL. Depending on an exemplary embodiment, the air layer AL can be filled with a transparent material having a predetermined refractive index.

[0061] The frame 210 can include a step 211 formed in an outer side. A height h1 of the step 211 can correspond to a predetermined height of an adhesive 300 disposed to fix the fingerprint sensor 200. The height h1 of the step 211 is a distance from the first side 100a of the display panel 100 to the step 211. The predetermined height of the adhesive 300 can be a height satisfying a required adhesiveness of the fingerprint sensor 200. That is, the step 211 is formed in the outer side of the frame 210 as a refractive pattern corresponding to the predetermined height of the adhesive 300.

[0062] The height h2 of the frame 210 can be higher than the predetermined height of the adhesive 300, and the height h1 of the step 211 can be lower than the height h2 of the frame 210. The height h1 of the step 211 can be about 70% or more of the height h2 of the frame 210. Alternatively, the height h1 of the step 211 can be about 450 µm or more. That is, the predetermined height of the adhesive 300 for fixing the fingerprint sensor 200 can be about 70% or more of the height h2 of the frame 210, or can be about 450 µm or more.

[0063] The lower portion of the wall structure of the frame 210 has a first width W1, and the upper portion of the wall structure can have a second width W2 that is smaller than the first width W1. Here, the lower portion of the wall structure means a portion below the height h1 of the step 211, and the upper portion of the wall structure means a portion higher than the height h1 of the step 211. The step 211 can have a shape cut as much as a third width W3 that is smaller than the first width W1 from the outer side of the wall structure. The upper portion of the wall structure can have the second width W2 located between the inner side of the contact sensing portion 220 and the step 211.

[0064] In Figure 2 In the above-described embodiment, the step is not formed at the inner side of the frame, but the shape of the inner side of the frame is not limited, and thus a curve corresponding to the step 211 in the outer side can be formed in the inner side, so that the thickness of the wall structure of the frame 210 can be constant.

[0065] The adhesive 300 bonds the fingerprint sensor 200 to the display panel 100 while contacting the outer side of the frame 210 and the first side 100a of the display panel 100. The height h3 of the portion of the adhesive 300 contacting the frame 210 can be the same as the height h1 of the step 211. Since the height h3 of the adhesive 300 is the same as the height h1 of the step 211, the required adhesion of the fingerprint sensor 200 can be satisfied.

[0066] After the adhesive 300 is applied in the process for bonding the fingerprint sensor 200 to the display panel 100, a worker can easily test whether the adhesive 300 is formed up to the height h1 of the step 211 by the naked eye. That is, the worker visually compares the height h3 of the adhesive 300 and the height h1 of the step 211, and when the height h3 of the adhesive 300 is lower than the height h1 of the step 211, determines that the adhesion of the fingerprint sensor 200 is not good, and when the height h3 of the adhesive 300 is the same as or higher than the height h1 of the step 211, can determine that the adhesion of the fingerprint sensor 200 is good. Accordingly, the adhesion inspection time of the fingerprint sensor 200 can be shortened.

[0067] Figure 3 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a display panel according to an exemplary embodiment.

[0068] Referring to Figure 3 , the height h3 of the adhesive 300 can not match the height h1 of the step 211 due to a process error. The height h3 of the adhesive 300 can be greater than the height h1 of the step 211. The height h3 of the adhesive 300 can be higher than the height h1 of the step 211 and lower than the height h2 of the frame 210. In this case, the required adhesion of the fingerprint sensor 200 can also be satisfied, and a worker can easily determine whether the adhesion of the fingerprint sensor 200 is defective.

[0069] In addition to features different from those of the exemplary embodiment of Figure 3 , features of the exemplary embodiment described with reference to Figure 1 and Figure 2 are applicable to the above-described exemplary embodiment of Figure 3 , and thus duplicate features will not be described.

[0070] Figure 4 is a cross-sectional view of a state in which a fingerprint sensor is attached to a display panel according to another exemplary embodiment. Figure 5 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a display panel according to an exemplary embodiment.

[0071] Referring to Figure 4 and Figure 5 , the frame 210 can include an inclined side 213 formed in an outer side thereof. The inclined side 213 can be a refractive pattern corresponding to a predetermined height of the adhesive 300.

[0072] The inclined side 213 has an inclination angle of less than 90 degrees with respect to the first side 100a of the display panel 100. The frame 210 can include a shape in which a width gradually decreases from the first side 100a of the display panel 100 toward a height h1' of the inclined side 213. The height h1' of the inclined side 213 can be a distance from the first side 100a of the display panel 100 to a topmost portion of the inclined side 213. The height h1' of the inclined side 213 can correspond to a predetermined height of the adhesive 300 for fixing the fingerprint sensor 200.

[0073] The height h1' of the inclined side 213 can be the same as the height h1 of the step 211 described with reference to Figure 2 and Figure 3 . Alternatively, the height h1' of the inclined side 213 can be lower than the height h1 of the step 211 described with reference to Figure 2 and Figure 3A height h1 of the described step 211. A height h1' of the inclined side 213 can be lower than a height h2 of the frame 210. The height h1' of the inclined side 213 can be about 70% or more of the height h2 of the frame 210. Alternatively, the height h1' of the inclined side 213 can be about 450 µm or more.

[0074] A bottom of the frame 210 in contact with the first side 100a of the display panel 100 at a lower portion of the wall structure can have a first width W1. An upper portion of the wall structure can have a second width W2 that is smaller than the first width W1. The lower portion of the wall structure means a portion below the height h1' of the inclined side 213, and the upper portion of the wall structure means a portion above the height h1' of the inclined side 213.

[0075] The inclined side 213 can be formed in an outer side of the lower portion of the wall structure. The inclined side 213 is formed within a fourth width W4 corresponding to a difference between the first width W1 and the second width W2, and a topmost portion of the inclined side 213 can contact the upper portion of the wall structure, and a bottommost portion of the inclined side 213 can contact the first side 100a of the display panel 100.

[0076] In Figure 4 and Figure 5 , the inner side of the frame 210 is shown as being vertical, but the shape of the inner side of the frame 210 is not limited, and a curve corresponding to the inclined side 213 at the outer surface can also be formed at the inner side of the frame 210, so that the wall structure can have a constant thickness.

[0077] By contacting the inclined side 213 of the frame 210 and the first side 100a of the display panel 100, the adhesive 300 can bond the fingerprint sensor 200 to the display panel 100. The adhesive 300 can cover the inclined side 213 of the frame 210. Since the frame 210 includes the inclined side 213 and the adhesive 300 covers the inclined side 213 of the frame 210, the adhesion of the fingerprint sensor 200 can be further enhanced.

[0078] As exemplarily shown in Figure 4 , a height h3 of a portion where the adhesive 300 contacts the frame 210 can be the same as the height h1' of the inclined side 213. Since the height h3 of the adhesive 300 is the same as the height h1' of the inclined side 213, the required adhesion of the fingerprint sensor 200 can be satisfied.

[0079] As exemplarily shown in Figure 5As exemplarily shown, the height h3 of the adhesive 300 contacting a portion of the frame 210 can be higher than the height h1' of the inclined side 213. The height h3 of the adhesive 300 can be higher than the height h1' of the inclined side 213 and can be lower than the height h2 of the frame 210. When the height h3 of the adhesive 300 is higher than the height h1' of the inclined side 213, the adhesion of the fingerprint sensor 200 can be satisfied.

[0080] After the adhesive 300 is applied in the process for joining the fingerprint sensor 200 to the display panel 100, a worker can compare the height h3 of the adhesive 300 and the height h1' of the inclined side 213 by naked eyes to determine whether the adhesive 300 is formed up to the height h1' of the inclined side 213. When the height h3 of the adhesive 300 is lower than the height h1' of the inclined side 213, the worker determines that the adhesion quality of the fingerprint sensor 200 is defective, and when the height h3 of the adhesive 300 is higher than or equal to the height h1' of the inclined side 213, the worker determines that the adhesion quality of the fingerprint sensor 200 is good.

[0081] In addition to features different from those of the exemplary embodiments of Figure 4 and Figure 5 , features of the exemplary embodiments described with reference to Figure 1 and Figure 2 are applicable to the above-described exemplary embodiments of Figure 4 and Figure 5 , and thus duplicate features will not be described.

[0082] Figure 6 is a cross-sectional view of a state in which a fingerprint sensor is attached to a display panel according to another exemplary embodiment. Figure 7 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a display panel according to an exemplary embodiment.

[0083] Referring to Figure 6 and Figure 7 , the frame 210 can include a groove 215 formed in an outer side thereof. The groove 215 can be a refractive pattern corresponding to a predetermined height of the adhesive 300.

[0084] A bottom of the frame 210 contacting the first side 100a of the display panel 100 at a lower portion of one wall structure has a first width W1, and an upper portion of the wall structure can have a second width W2 which is the same as the first width W1.

[0085] The recess 215 can include a shape recessed by up to a fifth width W5 in the outer side of the frame 210. The fifth width W5 is smaller than the first width W1. The recess 215 can be formed in the outer side of the lower portion of the wall structure. The uppermost portion of the recess 215 can contact the upper portion of the wall structure, and the lowermost portion of the recess 215 can contact the first side 100a of the display panel 100. The lower portion of the wall structure is a portion below the height h1” of the recess 215, and the upper portion of the wall structure is a portion above the height h1” of the recess 215.

[0086] The height h1” of the recess 215 can correspond to a predetermined height of the adhesive 300 provided to fix the fingerprint sensor 200. The height h1” of the recess 215 is a distance from the first side 100a of the display panel 100 to the uppermost portion of the recess 215, which contacts the upper portion of the wall structure. The height h1” of the recess 215 can be the same as the height h1 of the step 211 described with reference to Figure 2 and Figure 3 Alternatively, the height h1” of the recess 215 can be lower than the height h1 of the step 211 described with reference to Figure 2 and Figure 3 The height h1” of the recess 215 can be lower than the height h2 of the frame 210. The height h1” of the recess 215 can be 70% or more of the height h2 of the frame 210. Alternatively, the height h1” of the recess 215 can be about 450 µm or more.

[0087] In Figure 6 and Figure 7 , the inner side of the frame 210 is shown as being vertical, but the shape of the inner side of the frame 210 is not limited, and a curve corresponding to the recess 215 at the outer surface can also be formed at the inner side of the frame 210, so that the wall structure can have a constant thickness.

[0088] The adhesive 300 can join the fingerprint sensor 200 to the display panel 100 by contacting the recess 215 of the frame 210 and the first side 100a of the display panel 100. The adhesive 300 can be inserted into the recess 215 of the frame 210. Since the frame 210 includes the recess 215 and the adhesive 300 is inserted into the recess 215, the adhesion of the fingerprint sensor 200 can be further enhanced.

[0089] As exemplarily shown in Figure 6 , the height h3 of the portion of the adhesive 300 contacting the frame 210 can be the same as the height h1” of the recess 215. Since the height h3 of the adhesive 300 is the same as the height h1” of the recess 215, the required adhesion of the fingerprint sensor 200 can be satisfied.

[0090] As exemplarily shown in Figure 7As exemplarily shown, the height h3 of the adhesive 300 contacting the portion of the frame 210 can be higher than the height h1" of the groove 215. The height h3 of the adhesive 300 can be higher than the height h1" of the groove 215 and can be lower than the height h2 of the frame 210. Since the height h3 of the adhesive 300 is higher than the height h1" of the groove 215, the required adhesion of the fingerprint sensor 200 can be satisfied.

[0091] After the adhesive 300 is applied in the process for joining the fingerprint sensor 200 to the display panel 100, a worker can compare the height h3 of the adhesive 300 and the height h1" of the groove 215 by naked eye to determine whether the adhesive 300 is formed up to the height h1" of the groove 215. When the height h3 of the adhesive 300 is lower than the height h1" of the groove 215, the worker determines that the adhesion quality of the fingerprint sensor 200 is defective, and when the height h3 of the adhesive 300 is higher than or equal to the height h1" of the groove 215, the worker determines that the adhesion quality of the fingerprint sensor 200 is good.

[0092] In addition to features different from those of the exemplary embodiments of Figure 6 and Figure 7 , features of the exemplary embodiments described with reference to Figure 1 and Figure 2 are applicable to the above-described exemplary embodiments of Figure 6 and Figure 7 , and thus duplicate features will not be described.

[0093] Figure 8 is a cross-sectional view of an example of an optical type fingerprint sensor.

[0094] Referring to Figure 8 , when the fingerprint sensor is provided as an optical type fingerprint sensor, the sensing portion 220 can include a detector 221, an infrared filter 222, an adhesive layer 223, and a lens portion 224.

[0095] The detector 221 is provided in a base substrate 230 while being electrically connected with the base substrate 230. The detector 221 can include an element that converts received light into an electrical signal, such as a charge-coupled device (CCD) and a complementary metal-oxide semiconductor (CMOS), etc.

[0096] The infrared filter 222 is positioned in front of the detector 221 so that the received light is received by the detector 221 through the infrared filter 222. The infrared filter 222 reduces noise of the light received at the detector 221 by removing a long wavelength component of the light.

[0097] The adhesive layer 223 bonds the infrared filter 222 to the detector 221 by being disposed between the detector 221 and the infrared filter 222.

[0098] The air layer AL can be disposed between the infrared filter 222 and the lens portion 224 and between the lens portion 224 and the first side 100a of the display panel 100.

[0099] The lens portion 224 can be positioned at a predetermined distance from the infrared filter 222 by the air layer AL positioned between the infrared filter 222 and the lens portion 224. The lens portion 224 focuses the received light to the detector 221 after the light generated by the display panel 100 is reflected by a finger located on the second side 100b of the display panel 100.

[0100] In Figure 8 , the adhesive for bonding the frame supporting the sensing portion 220 and the fingerprint sensor to the display panel 100 is omitted, and in Figure 8 , the fingerprint sensor according to Figure 2 to Figure 7 , any one of the above exemplary embodiments can be applied to the frame 210 and the adhesive 300.

[0101] Figure 9 is an exploded perspective view of a display apparatus including a fingerprint sensor according to another exemplary embodiment. Figure 10 is a cross-sectional view of an example of a state in which a fingerprint sensor is attached to a back substrate according to an exemplary embodiment. Figure 11 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a back substrate according to an exemplary embodiment.

[0102] Referring to Figure 9 to Figure 11 , the display apparatus includes a display panel 100, a back substrate 400 facing the display panel 100, a fingerprint sensor 200 disposed in an upper portion of the back substrate 400, and an adhesive 300 bonding the fingerprint sensor 200 to the back substrate 400.

[0103] The back substrate 400 is disposed at a rear side of the display panel 100 and can be designed to insert or mount a portion of the display apparatus or a printed board module to the back substrate 400. The back substrate 400 can be a substrate supporting or protecting the rear side of the display panel 100.

[0104] The back substrate 400 includes a first side 400a and a second side 400b which is an opposite side of the first side 400a. The first side 400a of the back substrate 400 can face the first side 100a of the display panel 100. The fingerprint sensor 200 is attached to the first side 400a of the back substrate 400.

[0105] The base substrate 230 is positioned on the rear substrate 400, and the frame 210 and the sensing portion 220 can be positioned on the base substrate 230. In this case, the height h2 of the frame 210 from the first side 400a can be higher than the height of the sensing portion 220. This is to provide an air layer (corresponding to the air layer AL of Figure 2 ).

[0106] The frame 210 includes a step 211 formed in the outer side thereof, and the height h1 of the step 211 can include the thickness h5 of the base substrate 230, the height h1 of the step 211 corresponding to a predetermined height at which the adhesive 300 is disposed to fix the fingerprint sensor 200. The height h2 of the frame 210 can include the thickness h5 of the base substrate 230. The height h1 of the step 211 can be lower than the height h2 of the frame 210.

[0107] The adhesive 300 can join the fingerprint sensor 200 to the rear substrate 400 by contacting the outer side of the frame 210, the side surface of the base substrate 230, and the first side 400a of the rear substrate 400.

[0108] As exemplarily shown in Figure 10 , the height h3 of the adhesive 300 can be the same as the height h1 of the step 211. Alternatively, as exemplarily shown in Figure 11 , the height h3 of the adhesive 300 can be higher than the height h1 of the step 211. The height h3 of the adhesive 300 is the height of a portion of the adhesive 300 that contacts the outer side of the frame 210 and the side surface of the base substrate 230.

[0109] Except for features different from those of the exemplary embodiment of Figure 9 to Figure 11 , the features of the exemplary embodiments described with reference to Figure 1 and Figure 2 are applicable to the above-described exemplary embodiments of Figure 9 to Figure 11 , and thus the repeated features will not be described.

[0110] Figure 12 is a cross-sectional view of an example of a state in which a fingerprint sensor is attached to a rear substrate according to another exemplary embodiment. Figure 13 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a rear substrate according to an exemplary embodiment.

[0111] Referring to Figure 12 and Figure 13 , the frame 210 includes an inclined side 213 formed in the outer side thereof. The inclined side 213 has an inclined angle of less than 90 degrees with respect to the first side 400a of the rear substrate 400.

[0112] The height h1' of the inclined side 213 can include the thickness h5 of the base substrate 230, and the height h1' of the inclined side 213 corresponds to a predetermined height of the adhesive 300 disposed to fix the fingerprint sensor 200. The height h2 of the frame 210 can include the thickness h5 of the base substrate 230. The height h1' of the inclined side 213 can be lower than the height h2 of the frame 210.

[0113] The adhesive 300 can join the fingerprint sensor 200 to the back substrate 400 by contacting the inclined side 213 of the frame 210, the side surface of the base substrate 230, and the first side 400a of the back substrate 400.

[0114] As exemplarily shown in Figure 12 , the height h3 of the adhesive 300 can be the same as the height h1' of the inclined side 213. Alternatively, as exemplarily shown in Figure 13 , the height h3 of the adhesive 300 can be higher than the height h1' of the inclined side 213.

[0115] Except for features different from those of the exemplary embodiments of Figure 12 and Figure 13 , the features of the exemplary embodiments described with reference to Figure 4 and Figure 5 are applicable to the above-described exemplary embodiments of Figure 9 to Figure 11 and Figure 12 , and thus the duplicated features will not be described. Figure 13

[0116] Figure 14 is a cross-sectional view of an example of a state in which a fingerprint sensor is attached to a back substrate according to another exemplary embodiment. Figure 15 is a cross-sectional view of another example of a state in which a fingerprint sensor is attached to a back substrate according to an exemplary embodiment.

[0117] Referring to Figure 14 and Figure 15 , the frame 210 includes a groove 215 formed in an outer side thereof. A topmost portion of the groove 215 can contact an upper portion of a wall structure, and a bottommost portion of the groove 215 can contact the base substrate 230.

[0118] The height h1" of the groove 215 corresponding to a predetermined height of the adhesive 300 disposed to fix the fingerprint sensor 200 can include the thickness h5 of the base substrate 230. The height h2 of the frame 210 can include the thickness h5 of the base substrate 230. The height h1" of the groove 215 can be lower than the height h2 of the frame 210.

[0119] ​The adhesive 300 can join the fingerprint sensor 200 to the back substrate 400 by contacting the groove 215 of the frame 210, the side surface of the base substrate 230, and the first side 400a of the back substrate 400.

[0120] As exemplarily shown in Figure 14 , the height h3 of the adhesive 300 can be the same as the height h1” of the groove 215. Alternatively, as exemplarily shown in Figure 15 , the height h3 of the adhesive 300 can be higher than the height h1” of the groove 215.

[0121] In addition to the features different from those of the exemplary embodiments of Figure 14 and Figure 15 , the features of the exemplary embodiments described with reference to Figure 6 and Figure 7 , and the features of the exemplary embodiments described with reference to Figure 9 to Figure 11 are applicable to the above-described exemplary embodiments of Figure 14 and Figure 15 , and thus the duplicated features will not be described.

[0122] Figure 16 is a cross-sectional view of another example of an optical type fingerprint sensor.

[0123] Referring to Figure 16 , when the optical type fingerprint sensor is positioned on the first side 400a of the back substrate 400 facing the first side 100a of the display panel 100, the base substrate 230 can be positioned on the first side 400a of the back substrate 400. The detector 221, the adhesive layer 223, the infrared filter 222, and the lens portion 224 can be sequentially disposed on the base substrate 230. The air layer AL can be disposed between the infrared filter 222 and the lens portion 224 and between the lens portion 224 and the first side 100a of the display panel 100.

[0124] Light generated by the display panel 100 is reflected in a finger in the second side 100b of the display panel 100 and then received at the detector 221 through the lens portion 224 and the infrared filter 222. The detector 221 can convert the received light into an electrical signal.

[0125] In Figure 16 , the adhesive joining the support sensing portion 220 and the frame of the fingerprint sensor to the back substrate 400 is omitted, and the frame 210 and the adhesive 300 according to any one of the above-described exemplary embodiments in Figure 10 to Figure 15 can be applied to the fingerprint sensor of Figure 16 .

[0126] The accompanying drawings and detailed description of the application are merely exemplary of the application, and are intended to be used for descriptive purposes only and are not intended to limit the meaning or scope of the application. Therefore, it will be understood by those skilled in the art that various modifications and other exemplary embodiments of the application are possible.

[0127] <SYMBOL EXPLANATION>

[0128] 100: display panel

[0129] 200: fingerprint sensor

[0130] 210: frame

[0131] 211: step

[0132] 213: inclined side

[0133] 215: groove

[0134] 220: sensing portion

[0135] 230: base substrate

[0136] 300: adhesive

[0137] 400: rear substrate

Claims

1. A display device, wherein, The display device includes: a display panel or substrate; a fingerprint sensor disposed on a surface of a first side of the display panel or substrate and including a frame and a sensing portion disposed in the frame; and an adhesive disposed on the surface of the first side of the display panel or substrate, joining the fingerprint sensor to the surface of the first side of the display panel or substrate by contacting an outer side of the frame and the surface of the first side of the display panel or substrate, wherein a refractive pattern corresponding to a predetermined height of the adhesive is formed in the outer side of the frame, and a height of a portion of the adhesive contacting the frame beyond the surface is higher than or equal to a height of the refractive pattern beyond the surface, wherein the refractive pattern includes a step, an inclined side, or a groove formed in the outer side of the frame.

2. The display device according to claim 1, wherein A height of the step corresponds to the predetermined height of the adhesive, the height of the step being a distance from the first side of the display panel or substrate to the step.

3. The display device of claim 2, wherein, The height of the portion of the adhesive contacting the frame is the same as or higher than the height of the step.

4. The display device according to claim 1, wherein A height of the inclined side corresponds to the predetermined height of the adhesive, the height of the inclined side being a distance from the first side of the display panel or substrate to a topmost portion of the inclined side.

5. The display device of claim 4, wherein, The height of the portion of the adhesive contacting the frame is the same as or higher than the height of the inclined side.

6. The display device according to claim 1, wherein A height of the groove corresponds to the predetermined height of the adhesive, the height of the groove being a distance from the first side of the display panel or substrate to a topmost portion of the groove.

7. The display device of claim 6, wherein, The height of the portion of the adhesive contacting the frame is the same as or higher than the height of the groove.

Images