Display device

Abstract

A display device according to embodiments of the present invention comprises a base layer, a pixel layer disposed on the base layer and including a light-emitting element and a light-receiving element, an encapsulation layer covering the pixel layer, a black matrix disposed on the encapsulation layer and including a first aperture corresponding to a light-receiving element and a second aperture corresponding to a light-emitting element, a color filter disposed on the black matrix, a refractive layer disposed on the color filter and including a first refractive layer including a third aperture corresponding to a first aperture and a second refractive layer covering the first refractive layer, and a window disposed on the refractive layer. The cross-section of the third aperture is characterized by having a first inclined surface.

Description

Technology Field

[0001] The present invention relates to a display device including a light sensor. Background Technology

[0002] As the information society develops, the demand for display devices to show images is increasing in various forms. For example, display devices are being applied to a wide range of electronic devices, such as smartphones, digital cameras, laptop computers, navigation systems, and smart televisions.

[0003] Recently, research and development are underway on technology to integrate fingerprint sensors for fingerprint recognition into the display panel, which occupies the largest area of ​​the display device.

[0004] Meanwhile, the display device may include a cover window on the display panel for protection from external impact. If the thickness of the cover window increases, the fingerprint acquisition area (or sensing area) that the fingerprint sensor can acquire may also increase. In order for the fingerprint sensor to distinguish between the ridges and valleys of the fingerprint, it is desirable that the fingerprint acquisition area (or sensing area) of the fingerprint sensor be smaller than the period of the fingerprint. That is, if the fingerprint acquisition area (or sensing area) of the fingerprint sensor increases, the fingerprint sensing resolution may decrease. The problem to be solved

[0005] The technical problem to be solved is to provide a display device capable of reducing the fingerprint acquisition area (or sensing area) increased by the cover window.

[0006] However, the objectives of the present invention are not limited to the objectives described above and may be expanded in various ways without departing from the spirit and scope of the present invention. means of solving the problem

[0007] To achieve one objective of the present invention, a display device according to embodiments of the present invention comprises: a base layer; a pixel layer disposed on the base layer and comprising a light-emitting element and a light-receiving element; an encapsulation layer covering the pixel layer; a black matrix disposed on the encapsulation layer and comprising a first aperture corresponding to the light-receiving element and a second aperture corresponding to the light-emitting element; a color filter disposed on the black matrix; a refractive layer disposed on the color filter and comprising a first refractive layer including a third aperture corresponding to the first aperture and a second refractive layer covering the first refractive layer; and a window disposed on the refractive layer. The cross-section of the third aperture is characterized by having a first inclined surface.

[0008] The first inclined surface may have a first inclination angle that totally reflects reflected light from an object in contact with the window.

[0009] A portion of the reflected light reflected by the first inclined surface may be incident outside the light receiving area of ​​the light receiving element.

[0010] The above first inclination angle may be greater than 0° and less than or equal to 57.2°.

[0011] The first inclined surface may have a second inclined angle that refracts reflected light reflected from an object in contact with the window.

[0012] A portion of the reflected light refracted by the first inclined surface may be incident outside the light receiving area of ​​the light receiving element.

[0013] The above second inclination angle may be greater than 57.2° and less than 90°.

[0014] The refractive index of the first refractive layer may be smaller than the refractive index of the second refractive layer.

[0015] The width of the sensing area of ​​the light receiving element above can be calculated by the following Equation 1.

[0016] [Formula 1]

[0017] S=P+L1 / L2 (P+S0)

[0018] At this time, S is the sensing area, P is the width of the first aperture, L1 is the vertical distance from the bottom surface of the black matrix to the top surface of the window, L2 is the vertical distance from the bottom surface of the matrix to the top surface of the light-receiving element, and S0 is the width of the light-receiving element.

[0019] The width of the sensing area can be reduced in correspondence with the angle of inclination of the first inclined surface.

[0020] The width of the sensing area may be further reduced in correspondence with a second angle of inclination that refracts the reflected light, compared to a first angle of inclination that totally reflects the reflected light reflected from an object in contact with the window.

[0021] If the thickness of the first refractive layer increases between 0 and a preset value, the width of the sensing area may be reduced.

[0022] The thickness of the second refractive layer may be greater than 0 μm and less than or equal to 6 μm.

[0023] A touch sensor layer may be further included between the above-mentioned encapsulation layer and the above-mentioned matrix.

[0024] The first refractive layer includes a fourth opening corresponding to the second opening, and the cross-section of the fourth opening may have a second inclined surface.

[0025] The second inclined surface may have a third inclined angle that totally reflects the emitted light emitted from the light-emitting element or a fourth inclined angle that refracts the emitted light.

[0026] The above third inclination angle may be greater than 0° and less than or equal to 57.2°, and the above fourth inclination angle may be greater than 57.2° and less than 90°.

[0027] The angle of inclination of the first inclined surface and the angle of inclination of the second inclined surface may be different.

[0028] The thickness of the first refractive layer may differ between the thickness of the region corresponding to the third opening and the thickness of the region corresponding to the fourth opening.

[0029] The width of the third opening may be smaller than the width of the fourth opening. Effects of the invention

[0030] A display device according to one embodiment of the present invention can reduce the fingerprint acquisition area increased by the cover glass by further including a refractive layer between the display panel and the cover glass.

[0031] A display device according to one embodiment of the present invention can increase the frontal light efficiency of light emitted from a light-emitting element by further including a refractive layer between the display panel and the cover glass.

[0032] However, the effects of the present invention are not limited to the effects described above and may be extended in various ways without departing from the spirit and scope of the present invention. Brief explanation of the drawing

[0033] FIG. 1 is a block diagram showing a display device according to embodiments of the present invention. Figure 2 is a circuit diagram showing an example of a pixel and a light sensor included in the display device of Figure 1. Figure 3 is a cross-sectional view showing an example of the display area of ​​Figure 1. Figure 4 is a simplified cross-sectional view of Figure 3 to explain the sensing area of ​​the light-receiving element and the front light efficiency of the light-emitting element. FIG. 5a is a cross-sectional view of a display device including a refractive layer according to one embodiment. FIG. 5b is a diagram illustrating the optical path modified by the refractive layer shown in FIG. 5a. FIG. 6a is a cross-sectional view of a display device including a refractive layer according to one embodiment. FIG. 6b is a diagram illustrating the optical path modified by the refractive layer shown in FIG. 6a. FIG. 7 is a cross-sectional view of a display device including a refractive layer according to another embodiment. FIG. 8 is a cross-sectional view of a display device including a refractive layer according to another embodiment. FIG. 9 is a cross-sectional view of a display device including a refractive layer according to another embodiment. Specific details for implementing the invention

[0034] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the attached drawings. Identical components in the drawings are given the same reference numerals, and redundant descriptions of identical components are omitted.

[0035] FIG. 1 is a block diagram showing a display device according to embodiments of the present invention.

[0036] Referring to FIG. 1, the display device (1000) may include a display panel (100) and a driving circuit (200). In one embodiment, the driving circuit (200) may include a panel driving unit (210) and a sensor driving unit (220).

[0037] The display device (1000) may be implemented as a self-luminous display device including a plurality of self-luminous elements. In particular, the display device (1000) may be an organic light-emitting display device including organic light-emitting elements. However, as this is exemplary, the display device (1000) may be implemented as a display device including inorganic light-emitting elements, or a display device including light-emitting elements composed of a combination of inorganic and organic materials. Alternatively, the display device (1000) may be implemented as a liquid crystal display device, a plasma display device, a quantum dot display device, etc.

[0038] The display device (1000) may be a flat display device, a flexible display device, a curved display device, a foldable display device, a bendable display device. Additionally, the display device may be applied to a transparent display device, a head-mounted display device, a wearable display device, etc.

[0039] A display panel (100) includes a display area (AA) and a non-display area (NA). The display area (AA) may be an area provided with a plurality of pixels (PX). Each of the pixels (PX) may include at least one light-emitting element. For example, the light-emitting element may include a light-emitting layer (or, an organic light-emitting layer). The portion that emits light by the light-emitting element may be defined as a light-emitting area. The display device (1000) can display an image in the display area (AA) by driving the pixels (PX) in response to image data input from the outside.

[0040] In one embodiment, the display area (AA) may include a light sensor (PHS, or may be referred to as a sensor pixel). The light sensor (PHS) may include a light receiving element comprising a light receiving layer. Within the display area (AA), the light receiving layer of the light receiving element may be spaced apart from the light-emitting layer of the light-emitting element.

[0041] In one embodiment, a plurality of light sensors (PHS) may be spaced apart from each other and distributed across the entire area of ​​the display area (AA). However, as this is exemplary, only a portion of the display area (AA) may be set as a predetermined sensing area, and light sensors (PHS) may be provided in the corresponding sensing area. Additionally, light sensors (PHS) may be included in at least a portion of the non-display area (NA).

[0042] In one embodiment, light sensors (PHS) can detect light emitted from a light source (e.g., a light-emitting element) being reflected by an external object (e.g., a user's finger). For example, a user's fingerprint can be detected through the light sensors (PHS). Although the present invention is described below with the light sensors (PHS) being used for fingerprint detection as an example, in various embodiments, the light sensors (PHS) can detect various biometric information such as irises, veins, etc. Additionally, the light sensors (PHS) may detect external light and may perform functions such as gesture sensors, motion sensors, proximity sensors, light sensors, and image sensors.

[0043] The non-display area (NA) may be an area provided around the display area (AA). In one embodiment, the non-display area (NA) may comprehensively refer to the remaining area on the display panel (100) excluding the display area (AA). For example, the non-display area (NA) may include a wiring area, a pad area, and various dummy areas.

[0044] The display device (1000) may include a panel driving unit (210) and a sensor driving unit (220). Although the panel driving unit (210) and the sensor driving unit (220) are shown separately in FIG. 1, the technical concept of the present invention is not limited thereto. For example, at least a portion of the sensor driving unit (220) may be included in the panel driving unit (210) or may operate in conjunction with the panel driving unit (210).

[0045] The panel driving unit (210) can scan pixels (PX) of a display area (AA) and supply a data signal corresponding to image data (or an image) to the pixels (PX). The display panel (100) can display an image corresponding to the data signal.

[0046] In one embodiment, the panel driver (210) may supply a driving signal for fingerprint sensing to pixels (PX). This driving signal may be provided to cause the pixels (PX) to emit light and operate as a light source for a light sensor (PHS). In one embodiment, the panel driver (210) may also supply the driving signal for fingerprint sensing and / or other driving signals to the light sensor (PHS). However, as this is exemplary, the driving signals for fingerprint sensing may be provided by the sensor driver (220).

[0047] The sensor driving unit (220) can detect biometric information, such as a user fingerprint, based on detection signals received from optical sensors (PHS). In one embodiment, the sensor driving unit (220) may supply the driving signals to the optical sensors (PHS) and / or pixels (PX).

[0048] Figure 2 is a circuit diagram showing an example of a pixel and a light sensor included in the display device of Figure 1.

[0049] In FIG. 2, for convenience of explanation, a pixel (PX) located in the i-th pixel row (or i-th horizontal line) and connected to the j-th data line (Dj), and a light sensor (PHS) located in the i-th pixel row and connected to the k-th readout line (RXk) are shown (where i, j, and k are natural numbers).

[0050] Referring to FIGS. 1 and 2, the pixel (PX) includes a pixel circuit (PXC) and a light-emitting element (LED) connected thereto, and the light sensor (PHS) may include a sensor circuit (SSC) and a light-receiving element (LRD) connected thereto.

[0051] The first electrode (or first pixel electrode) of the light-emitting element (LED) may be connected to the fourth node (N4), and the second electrode (or second pixel electrode) may be connected to the second power supply (VSS). The light-emitting element (LED) may generate light of a predetermined brightness in correspondence with the amount of current (driving current) supplied from the first pixel transistor (T1).

[0052] In one embodiment, the light-emitting element (LED) may be an organic light-emitting diode comprising an organic light-emitting layer. In another embodiment, the light-emitting element (LED) may be an inorganic light-emitting element formed from an inorganic material. In another embodiment, the light-emitting element (LED) may be a light-emitting element composed of a composite of an inorganic material and an organic material.

[0053] The first electrode (or first sensor electrode) of the light receiving element (LRD) may be connected to the fifth node (N5), and the second electrode (or second sensor electrode) may be connected to the second power supply (VSS). The light receiving element (LRD) may generate carriers including free electrons and holes based on the intensity of light incident on the light receiving layer, and may generate a current (photocurrent) by the movement of carriers.

[0054] The pixel circuit (PXC) may include a first pixel transistor (T1), a second pixel transistor (T2), a storage capacitor (Cst), and a light-emitting element (LED). In one embodiment, the pixel circuit (PXC) may further include third to seventh pixel transistors (T3 to T7).

[0055] The first pixel transistor (T1) (or driving transistor) may be connected between a driving power line (PL1), to which the voltage of a driving power source (VDD1, or the first power source) is applied, and a first electrode of a light-emitting element (LED). The first pixel transistor (T1) may include a gate electrode connected to a first node (N1).

[0056] The first pixel transistor (T1) can control the amount of current (driving current) flowing from the driving power supply (VDD1) to the second power supply (VSS) via the light-emitting element (LED) based on the voltage of the first node (N1). To this end, the driving power supply (VDD1) can be set to a higher voltage than the second power supply (VSS).

[0057] The second pixel transistor (T2) can be connected between the j-th data line (Dj, hereinafter referred to as the data line) and the second node (N2). The gate electrode of the second pixel transistor (T2) can be connected to the i-th first scan line (S1i, hereinafter referred to as the first scan line). The second pixel transistor (T2) can be turned on when a first scan signal is supplied to the first scan line (S1i) to electrically connect the data line (Dj) and the second node (N2).

[0058] The third pixel transistor (T3) can be connected between the first node (N1) and the initialization power line (IPL) that transmits the voltage of the initialization power supply (Vint). The gate electrode of the third pixel transistor (T3) can be connected to the i-th second scan line (S2i, hereinafter referred to as the second scan line). The third pixel transistor (T3) can be turned on by a second scan signal supplied to the second scan line (S2i). When the third pixel transistor (T3) is turned on, the voltage of the initialization power supply (Vint) can be supplied to the first node (N1, i.e., the gate electrode of the first pixel transistor (T1)). In one embodiment, the timing of the second scan signal supplied to the second scan line (S2i) may be the same as the timing of the scan signal supplied to the i-1-th first scan line (e.g., referred to as S1i-1).

[0059] The fourth pixel transistor (T4) can be connected between the first node (N1) and the third node (N3). The gate electrode of the fourth pixel transistor (T4) can be connected to the first scan line (S1i). The fourth pixel transistor (T4) can be turned on simultaneously with the second pixel transistor (T2).

[0060] The fifth pixel transistor (T5) can be connected between the driving power line (PL1) and the second node (N2). The gate electrode of the fifth pixel transistor (T5) can be connected to the i-th light emission control line (Ei, hereinafter referred to as the light emission control line). The sixth pixel transistor (T6) can be connected between the third node (N3) and the light-emitting element (LED, or the fourth node (N4)). The gate electrode of the sixth pixel transistor (T6) can be connected to the light emission control line (Ei). The fifth pixel transistor (T5) and the sixth pixel transistor (T6) can be turned off when a light emission control signal is supplied to the light emission control line (Ei), and turned on in other cases.

[0061] According to the embodiment, when the fifth and sixth pixel transistors (T5, T6) are turned on, the current flowing through the first pixel transistor (T1) is transferred to the light-emitting element (LED), and the light-emitting element (LED) can emit light.

[0062] The seventh pixel transistor (T7) can be connected between the first electrode of the light-emitting element (LED) (i.e., the fourth node (N4)) and the initialization power line (IPL). The gate electrode of the seventh pixel transistor (T7) can be connected to the i-th third scan line (S3i, hereinafter referred to as the third scan line). The seventh pixel transistor (T7) can be turned on by a third scan signal supplied to the third scan line (S3i) to supply the voltage of the initialization power (Vint) to the first electrode of the light-emitting element (LED). In one embodiment, the timing of the third scan signal supplied to the third scan line (S3i) may be the same as the timing of one of the scan signals supplied to the first scan line (S1i), the i-1th first scan line (S1i-1), and the i+1th first scan line (e.g., S1i+1).

[0063] The storage capacitor (Cst) can be connected between the driving power line (PL1) and the first node (N1).

[0064] In one embodiment, the first scan signal may be supplied after the second scan signal is supplied. For example, the second scan signal and the first scan signal may be supplied with a difference of one horizontal period.

[0065] In one embodiment, the third scan signal may be supplied simultaneously with the first scan signal. However, as this is exemplary, the first scan signal may be supplied after the third scan signal is supplied. For example, the supply interval between the third scan signal and the first scan signal may be one horizontal period. Alternatively, the third scan signal may be supplied after the first scan signal is supplied.

[0066] The sensor circuit (SSC) may include a first sensor transistor (M1), a second sensor transistor (M2), and a third sensor transistor (M3).

[0067] The first sensor transistor (M1) and the second sensor transistor (M2) may be connected in series between the sensing power line (PL2) and the k-th readout line (RXk, hereinafter referred to as the readout line). A sensing power supply (VDD2) may be supplied through the sensing power line (PL2). For example, the voltage of the sensing power supply (VDD2) may be different from the voltage of the driving power supply (VDD1). However, this is exemplary, and the voltages of the sensing power supply (VDD2) and the driving power supply (VDD1) may be the same.

[0068] The gate electrode of the first sensor transistor (M1) can be connected to the fifth node (N5, or the first electrode (first sensor electrode)) of the photodetector (LRD). The first sensor transistor (M1) can generate a sensing current flowing from the sensing power line (PL2) to the readout line (RXk) based on the voltage of the fifth node (N5) caused by the photocurrent generated from the photodetector (LRD).

[0069] In one embodiment, the gate electrode of the second sensor transistor (M2) may be connected to the i-1th sensing scan line (SSi-1, hereinafter referred to as the previous sensing scan line). The second sensor transistor (M2) may be turned on when a sensing scan signal is supplied to the previous sensing scan line (SSi-1) to electrically connect the first sensor transistor (M1) and the readout line (RXk). Then, a sensing signal (sensing current) may be supplied to the sensor driver (220) through the readout line (RXk).

[0070] The third sensor transistor (M3) can be connected between the previous sensing scan line (SSi-1) and the fifth node (N5). The gate electrode of the third sensor transistor (M3) can be connected to the i-th sensing scan line (SSi, hereinafter referred to as the sensing scan line). The third sensor transistor (M3) can be turned on by a sensing scan signal supplied to the i-th sensing scan line (SSi) to supply the voltage supplied to the previous sensing scan line (SSi-1) to the fifth node (N5). The third sensor transistor (M3) can be used for voltage reset (or initialization) of the fifth node (N5).

[0071] In one embodiment, the third sensor transistor (M3) may include a plurality of sub-transistors (M3-1, M3-2) connected in series.

[0072] In one embodiment, the sensing scan signal supplied to the sensing scan line (SSi) may differ from the supply timing of the scan signals supplied to the first to third scan lines (S1i, S2i, S3i). However, as this is exemplary, the sensing scan signal supplied to the sensing scan line (SSi) may be supplied at the same time as one of the scan signals supplied to the first to third scan lines (S1i, S2i, S3i).

[0073] The pixel transistors (T1 to T7) and sensor transistors (M1 to M3) may be P-type transistors (e.g., PMOS transistors), but are not limited thereto. For example, at least one of the pixel transistors (T1 to T7) and sensor transistors (M1 to M3) may be implemented as an N-type transistor (e.g., NMOS). When the pixel transistors (T1 to T7) and sensor transistors (M1 to M3) are N-type transistors, the positions of the source region (source electrode) and the drain region (drain electrode) may be reversed.

[0074] Figure 3 is a cross-sectional view showing an example of the display area of ​​Figure 1.

[0075] Referring to FIGS. 1 through 3, a display device (1000) (or a display panel (100)) may include a base layer (BL), a backplane structure (BP), a pixel layer (PXL), and an encapsulation layer (TFE). The display panel (100) may further include a touch sensor layer (TSL), a black matrix (BM), color filters (CF1, CF2), a refractive layer (RFL), and a window (WIN). The black matrix (BM) may form an optical system for transmitting light to a light receiving element (LRD).

[0076] The cross-sectional view of FIG. 3 shows a partial configuration of a pixel (PX) and a light sensor (PHS). FIG. 3 will focus on describing the configuration of the first pixel transistor (T1) and the third sensor transistor (M3). For convenience of explanation, FIG. 3 shows the first pixel transistor (T1) directly connected to a light-emitting element (LED). The first pixel transistor (T1) may include a first active pattern (ACT1), a first gate electrode (GE1), a first source electrode (11), and a first drain electrode (12). The third sensor transistor (M3) may include a tenth active pattern (ACT10), a tenth gate electrode (GE10), a tenth source electrode (13), and a tenth drain electrode (14).

[0077] The base layer (BL) may be made of an insulating material such as glass or resin. Additionally, the base layer (BL) may be made of a flexible material that allows it to be bent or folded, and may have a single-layer or multi-layer structure.

[0078] A backplane structure (BP) including a pixel circuit (PXC) and a sensor circuit (SSC) may be provided on a base layer (BL). The backplane structure (BP) may include semiconductor layers (ACT1, ACT10), conductive layers (GE1, GE10, 11, 12, 13, 14), and insulating layers (GI, IL1, IL2, IL3).

[0079] A buffer layer (BF) may be formed on the base layer (BL). The buffer layer (BF) can prevent impurities from diffusing into the transistors (T1, M3). The buffer layer (BF) may be omitted depending on the material and process conditions of the base layer (BL).

[0080] A semiconductor layer comprising a first active pattern (ACT1) and a tenth active pattern (ACT10) is provided on the buffer layer (BF). In one embodiment, the semiconductor layer may include a polysilicon semiconductor. For example, the semiconductor layer may be formed through a low-temperature polysilicon process (e.g., a low-temperature polysilicon (LTPS) process). However, this is exemplary, and at least a portion of the semiconductor layer may be formed from an oxide semiconductor, a metal oxide semiconductor, etc.

[0081] A gate insulating layer (GI) may be provided on the semiconductor layer. The gate insulating layer (GI) may be an inorganic insulating layer made of an inorganic material.

[0082] A first conductive layer comprising a first gate electrode (GE1) and a tenth gate electrode (GE10) may be provided on the gate insulating layer (GI). The first gate electrode (GE1) may cover an area corresponding to the channel region of the first active pattern (ACT1). The tenth gate electrode (GE10) may cover an area corresponding to the channel region of the tenth active pattern (ACT10).

[0083] A first conductive layer comprising a first gate electrode (GE1) and a tenth gate electrode (GE10) may be made of a metal. For example, the first conductive layer may be made of at least one of metals such as gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy of metals. Additionally, the first conductive layer may be formed as a single layer or as a multilayer in which two or more materials among metals and alloys are stacked.

[0084] A first insulating layer (IL1, or a first interlayer insulating layer) may be provided on the first conductive layer. The first insulating layer (IL1) may be an inorganic insulating layer made of an inorganic material. Polysiloxane, silicon nitride, silicon oxide, silicon oxynitride, etc. may be used as inorganic materials.

[0085] A second conductive layer may be provided on the first insulating layer (IL1). In one embodiment, the second conductive layer may include a readout line (RXk), an initialization power line (IPL), and a sensing power line (PL2). The second conductive layer may be made of at least one of metals such as gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy of metals. Additionally, the second conductive layer may be formed as a single layer, but is not limited thereto, and may be formed as a multilayer in which two or more materials among metals and alloys are stacked.

[0086] A second insulating layer (IL2, or a second interlayer insulating layer) may be provided on the second conductive layer. The second insulating layer (IL2) may be an inorganic insulating layer made of an inorganic material. Polysiloxane, silicon nitride, silicon oxide, silicon oxynitride, etc. may be used as inorganic materials.

[0087] A third conductive layer including a first source electrode (11), a first drain electrode (12), a tenth source electrode (13), and a tenth drain electrode (14) may be provided on the second insulating layer (IL2). FIG. 3 is illustrated on the premise that the first pixel transistor (T1) and the third sensor transistor (M3) are P-type transistors, but the source electrode and drain electrode may differ depending on the type of transistor, etc.

[0088] The first source electrode (11) and the first drain electrode (12) can respectively contact the source region and the drain region on both sides of the first active pattern (ACT1) through contact holes formed in the gate insulating layer (GI), the first insulating layer (IL1), and the second insulating layer (IL2).

[0089] The 10th source electrode (13) and the 10th drain electrode (14) can respectively contact the source region and drain region on both sides of the 10th active pattern (ACT2) through contact holes formed in the 1st insulating layer (INS1), the interlayer insulating layer (IL), and the gate insulating layer (GI).

[0090] A third conductive layer comprising source electrodes (11, 13) and drain electrodes (12, 14) may be made of a metal. For example, the third conductive layer may be made of at least one of metals such as gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy of metals.

[0091] In one embodiment, a passivation layer (not shown) may be provided on the third conductive layer. The passivation layer may be an inorganic insulating layer made of an inorganic material. Polysiloxane, silicon nitride, silicon oxide, silicon oxynitride, etc. may be used as the inorganic material.

[0092] A third insulating layer (IL3) may be provided on the third conductive layer (or passivation layer). In one embodiment, the third insulating layer (IL3) may be an organic insulating layer made of an organic material. Organic insulating materials such as polyacrylic compounds, polyimide compounds, fluorinated carbon compounds like Teflon, and benzocyclobutene compounds may be used as organic materials. Alternatively, the third insulating layer (IL3) may be an inorganic insulating layer made of an inorganic material.

[0093] FIG. 3 is illustrated as having a third insulating layer (IL3) provided on a second insulating layer (IL2), but the arrangement of the insulating layers may vary. For example, only a passivation layer may be provided on the source and drain electrodes (11, 12, 13, 14), and a first pixel electrode (PEL1) and a first sensor electrode (SEL1) may be provided on the passivation layer. Alternatively, an additional conductive layer and a fourth insulating layer covering it may be provided on the third insulating layer (IL3), and a first pixel electrode (PEL1) and a first sensor electrode (SEL1) may be provided on the fourth insulating layer.

[0094] A pixel layer (PXL) may be provided on the backplane structure (BP). The pixel layer (PXL) may include a light-emitting element (LED) connected to a pixel circuit (PXC) and a light-receiving element (LRD) connected to a sensor circuit (SSC).

[0095] In one embodiment, the light-emitting element (LED) may include a first pixel electrode (PEL1), a first hole transport layer (HTL1), a light-emitting layer (EML), an electron transport layer (ETL), and a second pixel electrode (PEL2). In one embodiment, the light-receiving element (LRD) may include a first sensor electrode (SEL1), a second hole transport layer (HTL2), an electron blocking layer (EBL), a light-receiving layer (LRL), an electron transport layer (ETL), and a second sensor electrode (SEL2).

[0096] In one embodiment, the first pixel electrode (PEL1) and the first sensor electrode (SEL1) may be composed of a metal layer such as Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or alloys thereof, and / or ITO (indium tin oxide), IZO (indium zinc oxide), ZnO (zinc oxide), ITZO (indium tin zinc oxide), etc. The first pixel electrode (PEL1) may be connected to the first drain electrode (12) through a contact hole. The first sensor electrode (SEL1) may be connected to the tenth drain electrode (14) through a contact hole.

[0097] The first pixel electrode (PEL1) and the first sensor electrode (SEL1) can be formed simultaneously through patterning using a mask.

[0098] A bank layer (BK, or pixel defining film) that partitions a light-emitting region (EA) and a light-receiving region (RA) may be provided on the third insulating layer (IL3) on which the first pixel electrode (PEL1) and the first sensor electrode (SEL1) are formed. The portion that receives light by the light-receiving element (LRD) may be defined as the light-receiving region (RA).

[0099] The bank layer (BK) may be an organic insulating layer made of an organic material. Organic materials may include acrylic resin, epoxy resin, phenolic resin, polyamide resin, polyimide resin, etc.

[0100] Additionally, the bank layer (BK) may contain a light-absorbing material or be coated with a light-absorbing agent to absorb light introduced from the outside. For example, the bank layer (BK) may contain a carbon-based black pigment. However, it is not limited thereto, and the bank layer (BK) may also contain opaque metallic materials with high light absorption rates, such as chromium (Cr), molybdenum (Mo), an alloy of molybdenum and titanium (MoTi), tungsten (W), vanadium (V), niobium (Nb), tantalum (Ta), manganese (Mn), cobalt (Co), or nickel (Ni).

[0101] The bank layer (BK) exposes the upper surface of the first pixel electrode (PEL1) and the upper surface of the first sensor electrode (SEL1) and may protrude from the third insulating layer (IL3) along the periphery of the light-emitting region (EA) and the light-receiving region (RA). That is, the bank layer (BK) may include openings corresponding to the light-emitting region (EA) and the light-receiving region (RA).

[0102] A first hole transport layer (HTL1) may be provided on the upper surface of the first pixel electrode (PEL1) exposed by the bank layer (BK), and a second hole transport layer (HTL2) may be provided on the upper surface of the exposed first sensor electrode (SEL1). Holes may be moved to the light-emitting layer (EML) through the first hole transport layer (HTL1), and holes may be moved to the light-receiving layer (LRL) through the second hole transport layer (HTL2).

[0103] In one embodiment, depending on the materials of the light-emitting layer (EML) and the light-receiving layer (LRL), the first hole transport layer (HTL1) and the second hole transport layer (HTL2) may be the same or different.

[0104] In the light-emitting region (EA) surrounded by the bank layer (BK), a light-emitting layer (EML) may be provided on the first hole transport layer (HTL1). In one embodiment, the light-emitting layer (EML) may be composed of an organic light-emitting layer. Depending on the organic material included in the light-emitting layer (EML), the light-emitting layer (EML) may emit light such as red light, green light, or blue light.

[0105] In one embodiment, as shown in FIG. 3, an electron blocking layer (EBL) may be provided on a second hole transport layer (HTL2) in a light-receiving region (RA) surrounded by a bank layer (BK). The electron blocking layer (EBL) can prevent the charge of the light-receiving layer (LRL) from moving to the hole transport layer (HTL). In one embodiment, the electron blocking layer (EBL) may comprise the same material as the first hole transport layer (HTL1) in the light-emitting region.

[0106] In one embodiment, the electron blocking layer (EBL) may be omitted.

[0107] A light-receiving layer (LRL) may be disposed on the electron blocking layer (EBL) or the second hole transport layer (HTL2). The light-receiving layer (LRL) can detect the intensity of light by emitting electrons in response to light of a specific wavelength band.

[0108] In one embodiment, the light-receiving layer (LRL) may include a low-molecular-weight organic material. For example, the light-receiving layer (LRL) is composed of a phthalocyanine compound comprising one or more metals selected from the group consisting of copper (Cu), iron (Fe), nickel (Ni), cobalt (Co), manganese (Mn), aluminum (Al), palladium (Pd), tin (Sn), indium (In), lead (Pb), titanium (Ti), rubidium (Rb), vanadium (V), gallium (Ga), terbium (Tb), cerium (Ce), lanthanum (La), and zinc (Zn).

[0109] Alternatively, the low molecular weight organic material included in the light-receiving layer (LRL) may be composed of a bi-layer comprising a layer comprising a phthalocyanine compound comprising one or more metals selected from the group consisting of copper (Cu), iron (Fe), nickel (Ni), cobalt (Co), manganese (Mn), aluminum (Al), palladium (Pd), tin (Sn), indium (In), lead (Pb), titanium (Ti), rubidium (Rb), vanadium (V), gallium (Ga), terbium (Tb), cerium (Ce), lanthanum (La), and zinc (Zn), and a layer comprising C60, or may be composed of a single mixing layer comprising a phthalocyanine compound and a mixture of C60.

[0110] However, as this is exemplary, the light-receiving layer (LRL) may also have a polymer organic layer.

[0111] Meanwhile, in FIG. 3, for convenience of explanation, the area of ​​the light-receiving region (RA) and the area of ​​the light-emitting region (EA) are depicted similarly, but the area of ​​the light-receiving region (RA) may be smaller than the area of ​​the light-emitting region (EA). Therefore, the presence of the light-receiving region (RA) does not significantly affect the light emission of the pixel (PX) for image display, and image quality above a certain level can be guaranteed.

[0112] In one embodiment, an electron transport layer (ETL) may be provided on the light-emitting layer (EML) and the light-receiving layer (LRL). The electron transport layer (ETL) may be integrally formed on the display area (AA). Thus, the electron transport layer (ETL) may be in contact with the upper surface of the bank layer (BK).

[0113] However, as this is exemplary, at least one of the first hole transport layer (HTL1), the second hole transport layer (HTL2), the electron blocking layer (EBL), and the electron transport layer (ETL) may be omitted. Additionally, functional layers such as a hole injection layer and an electron injection layer may be added.

[0114] A second pixel electrode (PEL2) may be provided on the electron transport layer (ETL) of the light-emitting region (EA), and a second sensor electrode (SEL2) may be provided on the electron transport layer (ETL) of the light-receiving region (RA). In one embodiment, the second pixel electrode (PEL2) and the second sensor electrode (SEL2) may be a common electrode (CD) formed integrally on the display region (AA). The voltage of the second power supply (VSS) may be supplied to the second pixel electrode (PEL2) and the second sensor electrode (SEL2).

[0115] The second pixel electrode (PEL2) and the second sensor electrode (SEL2) may be composed of a metal layer such as Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, and / or a transparent conductive layer such as ITO, IZO, ZnO, ITZO. In one embodiment, the common electrode (CD) may be composed of a double layer or more including a metal thin layer, and may be composed of, for example, a triple layer of ITO / Ag / ITO.

[0116] An encapsulation layer (TFE) may be provided on a common electrode (CD) comprising a second pixel electrode (PEL2) and a second sensor electrode (SEL2). The encapsulation layer (TFE) may be composed of a single layer, but may be composed of multiple layers. In one embodiment, the encapsulation layer (TFE) may have a stacked structure in which an inorganic material, an organic material, and an inorganic material are deposited in that order. The top layer of the encapsulation layer (TFE) may be formed of an inorganic material.

[0117] In one embodiment, a touch sensor layer (TSL) may be disposed on an encapsulation layer (TFE). The touch sensor layer (TSL) may include a conductive pattern for touch detection and an insulating layer. The conductive pattern of the touch sensor layer (TSL) may be composed of a single layer or a double layer formed with an insulating layer in between.

[0118] In one embodiment, to ensure image quality and light reception amount, the conductive pattern of the touch sensor layer (TSL) may be arranged to avoid the light-emitting region (EA) and the light-receiving region (RA).

[0119] A black matrix (BM) may be provided on an encapsulation layer (TFE) or a touch sensor layer (TSL). The black matrix (BM) may absorb or block light entering from the outside. The black matrix (BM) may include an organic light-blocking material. For example, the organic light-blocking material may include at least one of carbon black and titanium black, but is not necessarily limited thereto.

[0120] The black matrix (BM) may include a plurality of openings (OP1, OP2). In one embodiment, the black matrix (BM) may be formed by a patterning process using a mask or a printing process, etc.

[0121] In one embodiment, the black matrix (BM) may be provided superimposed on the bank layer (BK). Additionally, the black matrix (BM) may be positioned to cover the conduction patterns of the touch sensor layer (TSL). The black matrix (BM) is positioned to avoid the light-emitting region (EA). For example, the black matrix (BM) may be provided in the form of a pattern including a second opening (OP2) that superimposes the light-emitting region (EA).

[0122] The first aperture (OP1) of the black matrix (BM) can be superimposed on the light receiving region (RA). The first aperture (OP1) of the black matrix (BM) can provide an optical path for external light to be incident on the light receiving layer (LRL).

[0123] For example, the vertical light component of the external light can be transmitted to the light receiving layer (LRL) through the first aperture (OP1). Alternatively, the phase of the image formed on the light receiving layer (LRL) after passing through the first aperture (OP1) can be reversed 180 degrees from the external light. However, this is exemplary, and the function of the first aperture (OP1) as an optical system can be determined by the width of the first aperture (OP1), the thickness of the black matrix (BM), the distance between the black matrix (BM) and the light receiving layer (LRL), the distance between the black matrix (BM) and the upper structure (window (WIN)), etc.

[0124] In one embodiment, color filters (CF1, CF2) may be disposed on the touch sensor layer (TSL) and the black matrix (BM). Depending on the color of the light emitted from the light-emitting region (EA), the second color filter (CF2) may be one of a red color filter, a green color filter, and a blue color filter. For example, if green light is output from the light-emitting region (EA), the second color filter (CF2) may be a green color filter.

[0125] In one embodiment, the color filters (CF1, CF2) may come into direct contact with at least a portion of the upper and side surfaces of the black matrix (BM). For example, the color filters (CF1, CF2) may be placed directly on the black matrix (BM). Alternatively, no material other than a bonding member is interposed between the color filters (CF1, CF2) and the black matrix (BM) to bond them.

[0126] The second color filter (CF2) can selectively pass light emitted from a light-emitting element (LED) according to wavelength or color. When a black matrix (BM) and color filters (CF1, CF2) are placed on a touch sensor layer (TSL), external light reflection can be sufficiently prevented without a polarizing layer having a thickness of generally 80 μm or more. In addition, since it has a higher transmittance than a polarizing layer, contrast and light efficiency can be improved.

[0127] In one embodiment, a first color filter (CF1) may be provided superimposed on a light receiving area (RA). The first color filter (CF1) may be one of a red color filter, a green color filter, and a blue color filter depending on the color light detected by the light receiving layer (LRL). For example, if the light receiving layer (LRL) absorbs light in the green wavelength range, the first color filter (CF1) may be a green filter. That is, the first color filter (CF1) may be set independently of the light emission color of adjacent pixels.

[0128] Meanwhile, the black matrix (BM) and color filters (CF1, CF2) can function as an anti-reflection layer that blocks external light reflection. Since the display panel (100) includes the black matrix (BM) and color filters (CF1, CF2) that function as an anti-reflection layer, a separate polarizing layer is not included (is removed). Accordingly, a decrease in brightness is prevented, and at the same time, the thickness of the display panel (100) can be minimized.

[0129] In one embodiment, a refractive layer (RFL) may be disposed on color filters (CF1, CF2). The refractive layer (RFL) may include sub-refractive layers having different refractive indices. The refractive layer (RFL) can change the path of light reflected from an external object to a light receiving element (LRD) and the path of light emitted from a light emitting element (LED). The refractive layer (RFL) will be described in detail later with reference to FIGS. 5a through 9.

[0130] In one embodiment, a window (WIN) may be further included on the refractive layer (RFL). The window (WIN) serves to cover and protect the structures placed underneath it. The window (WIN) may be attached to the refractive layer (RFL) via an adhesive. For example, the adhesive may include OCA (Optically Clear Adhesive), SVR (Super View Resin), PSA (Pressure Sensitive Adhesive), or OCR (Optically Clear Resin).

[0131] The window can be made of a transparent material. The window can be made of plastic, in which case the window can have flexible properties. The thickness of the window can be 500 μm.

[0132] Examples of plastics applicable to WIN include, but are not limited to, polyimide, polyacrylate, polymethylmethacrylate, polycarbonate, polyethylenenaphthalate, polyvinylidene chloride, polyvinylidene fluoride, polystyrene, ethylene vinylalcohol copolymer, polyethersulfone, polyetherimide, polyphenylene sulfide, polyallylate, triacetyl cellulose, cellulose acetate propionate, etc. WIN may be made by including one or more of the plastic materials listed above.

[0133] FIG. 4 is a simplified cross-sectional view of FIG. 3 to explain the sensing area of ​​the light-receiving element and the front light efficiency of the light-emitting element. In this case, the sensing area may be a fingerprint acquisition area when the light-receiving element functions as a fingerprint sensor.

[0134] Referring to FIGS. 1 and FIGS. 4, the sensing area (S) (or width of the sensing area) of the light receiving element (LRD) can be calculated by the following Equation 1.

[0136] [Formula 1]

[0137]

[0138] (wherein S is the sensing area, P is the width of the first aperture (OP1), L1 is the vertical distance from the bottom surface of the black matrix (BM) to the top surface of the window (WIN), L2 is the vertical distance from the bottom surface of the black matrix (BM) to the top surface of the light receiving element (LRD), and S0 is the width of the light receiving element (LRD))

[0140] The display device (1000) may include a window (WIN) on color filters (CF1, CF2) for protection from external impact. However, due to the thickness of the window (WIN), the vertical distance (L1) from the lower surface of the black matrix (BM) to the upper surface of the window (WIN) increases, so the width of the sensing area (S) of the light receiving element (LRD) may increase. For example, if the light receiving element (LRD) is a fingerprint sensor, the object (OBJ) in contact with the window (WIN) may be a user's finger, and in order to distinguish the ridges and valleys of the fingerprint, the width of the sensing area (S) must be smaller than the period of the fingerprint, but if the width of the sensing area (S) increases, the fingerprint sensing resolution may decrease.

[0141] Meanwhile, if the vertical distance (L1) from the lower surface of the black matrix (BM) to the upper surface of the window (WIN) increases due to the thickness of the window (WIN), the frontal light efficiency of the light-emitting element (LED) may decrease. In this case, the frontal light efficiency can be defined as the ratio of light emitted toward the front (or display surface (IS)) among the light emitted from the light-emitting element (LED). For example, the frontal light efficiency when the window (WIN) is not attached may correspond to a first width (W1), and the frontal light efficiency when the window (WIN) is attached may correspond to a second width (W2). The frontal light efficiency corresponding to a second width (W2) which is greater than the first width (W1) may be lower than the frontal light efficiency of the light-emitting element (LED) corresponding to the first width (W1).

[0142] Hereinafter, a method for reducing the width of the sensing area (S) of the light-receiving element (LRD) and improving the front light efficiency of the light-emitting element (LED) by placing a refractive layer (RFL of FIG. 3) between the window (WIN) and the light-receiving element (LRD) even when the display device (1000) includes a window (WIN).

[0143] FIG. 5a is a cross-sectional view of a display device including a refractive layer according to one embodiment. FIG. 5b is a diagram illustrating the light path modified by the refractive layer shown in FIG. 5a.

[0144] The embodiment illustrated in FIG. 5a differs from the embodiment illustrated in FIG. 4 in that it further includes a refractive layer (RFL) between the color filters (CF1, CF2) and the window (WIN).

[0145] A refractive layer (RFL) according to one embodiment may be disposed on color filters (CF1, CF2) and may include a first refractive layer (RFL1) and a second refractive layer (RFL2) covering the first refractive layer (RFL1). The first refractive layer (RFL1) may include a third aperture (OP3) corresponding to a first aperture (OP1) and a fourth aperture (OP4) corresponding to a second aperture (OP2). In this case, the light receiving region (RA) of the light receiving element (LRD) may overlap with the first aperture (OP1) and the third aperture (OP3) in the thickness direction. Additionally, the light emitting region (EA) of the light emitting element (LED) may overlap with the second aperture (OP2) and the fourth aperture (OP4) in the thickness direction.

[0146] According to one embodiment, a first refractive layer (RFL1) can be formed through a photolithography process. A photoresist is applied to color filters (CF1, CF2), and after patterning by exposure and development, a first refractive layer (RFL1) having third and fourth apertures (OP3, OP4) can be formed using photocuring or the like. A second refractive layer (RFL2) can be disposed on the first refractive layer (RFL1). The second refractive layer (RFL2) can be formed on the color filters (CF1, CF2) while covering the first refractive layer (RFL1).

[0147] According to one embodiment, the cross-section of the third opening (OP3) may have a first inclined surface (SP1), and the cross-section of the fourth opening (OP4) may have a second inclined surface (SP2). In this case, the first inclined surface (SP1) and the second inclined surface (SP2) may be symmetrical. The first inclined surface (SP1) and the second inclined surface (SP2) may have a first inclination angle (θ1). The first inclination angle (θ1) may be an angle that causes total reflection of light incident on the first inclined surface (SP1) (e.g., reflected light reflected from an object (OBJ) in contact with the window (WIN), light emitted from a light-emitting element (LED)). For example, the first inclination angle (θ1) may be an angle greater than 0° and less than or equal to 57.2°.

[0148] According to one embodiment, the refractive index of the first refractive layer (RFL1) may be lower than the refractive index of the second refractive layer (RFL2). The first refractive layer (RFL1) may include, for example, an acrylic resin, which is a material having a relatively low refractive index. Additionally, the second refractive layer (RFL2) may include, for example, at least one of zirconium oxide (ZrOx), aluminum oxide (AlOx), and titanium oxide (TiOx) and a siloxane to have a relatively high refractive index.

[0149] Referring to FIG. 5a and FIG. 5b, assuming that the width (P) of the first aperture (OP1) is 6 μm, the vertical distance (L1) from the bottom surface of the black matrix (BM) to the top surface of the window (WIN) is 575 μm, the vertical distance (L2) from the bottom surface of the black matrix (BM) to the top surface of the light receiving element (LRD) is 11.5 μm, and the width (S0) of the light receiving element (LRD) is 11 μm, the width of the sensing area (S) when the refractive layer (RFL) is omitted according to Equation 1 may be 856 μm.

[0150] On the other hand, when a refractive layer (RFL) is included, the first refractive layer (RFL1) has a first inclination angle (θ1) that totally reflects light incident on the first inclined surface (SP1), and since the refractive index of the first refractive layer (RFL1) is smaller than the refractive index of the second refractive layer (RFL2), some of the reflected light (RL1) can be reflected from the first inclined surface (SP1) of the third aperture (OP3) and incident outside the light receiving region (RA) of the light receiving element (LRD). As a result, the sensing region (S1) of the light receiving element (LRD) can be reduced compared to the width of the sensing region (S) when the refractive layer (RFL) is not included. For example, when the thickness of the first refractive layer (RFL) is 3 μm and the first inclination angle (θ1) is 50°, the sensing region (S1) can be reduced to 785 μm.

[0151] Meanwhile, the second inclined surface (SP2) of the fourth aperture (OP4) also has a first inclined angle (θ1) that causes total reflection of incident light, and since the refractive index of the first refractive layer (RFL1) is smaller than the refractive index of the second refractive layer (RFL2), light emitted from a light-emitting element (LED) can be total reflected when incident on the first inclined surface (SP1). Light directed toward the side direction of the display device (1000, see FIG. 1) can be reflected from the second inclined surface (SP2) and emitted toward the front direction of the display device (1000) (e.g., display surface (IS)). As a result, the front light efficiency of the display device (1000) can be increased. For example, the front light efficiency in the case of including a refractive layer (RFL) having the first inclined angle (θ1) can correspond to the third width (W3). At this time, the third width (W3) may be smaller than the second width (W2, see FIG. 4) corresponding to the frontal light efficiency when the refractive layer (RFL) is not included. That is, the frontal light efficiency corresponding to the second width (W2), which is smaller than the first width (W1), may be greater than the frontal light efficiency of the light-emitting element (LED) corresponding to the first width (W1).

[0152] FIG. 6a is a cross-sectional view of a display device including a refractive layer according to one embodiment. FIG. 6b is a diagram illustrating the light path modified by the refractive layer shown in FIG. 6a.

[0153] The embodiment illustrated in FIG. 6a differs from the embodiments illustrated in FIG. 5a and FIG. 5b, which have a first inclination angle (θ1) that causes total reflection of incident light, in that the refractive layer (RFL) has a second inclination angle (θ2) that causes refractive light.

[0154] According to one embodiment, the cross-section of the third opening (OP3) may have a first inclined surface (SP1), and the cross-section of the fourth opening (OP4) may have a second inclined surface (SP2). In this case, the first inclined surface (SP1) and the second inclined surface (SP2) may be symmetrical. The first inclined surface (SP1) and the second inclined surface (SP2) may have a second inclination angle (θ2). The second inclination angle (θ2) may be an angle that refracts light incident on the second inclined surface (SP2) (e.g., reflected light reflected from an object (OBJ) in contact with the window (WIN)). For example, the second inclination angle (θ2) may be an angle greater than 57.2° and less than 90°.

[0155] According to one embodiment, the refractive index of the first refractive layer (RFL1) may be smaller than the refractive index of the second refractive layer (RFL2).

[0156] Referring to FIG. 6a and FIG. 6b, assuming that the width (P) of the first aperture (OP1) is 6 μm, the vertical distance (L1) from the bottom surface of the black matrix (BM) to the top surface of the window (WIN) is 575 μm, the vertical distance (L2) from the bottom surface of the black matrix (BM) to the top surface of the light receiving element (LRD) is 11.5 μm, and the width (S0) of the light receiving element (LRD) is 11 μm, the width of the sensing area (S) when the refractive layer (RFL) is omitted according to Equation 1 may be 856 μm.

[0157] On the other hand, when a refractive layer (RFL) is included, the first refractive layer (RFL1) has a second inclination angle (θ2) that refracts light incident on the first inclined surface (SP1), and since the refractive index of the first refractive layer (RFL1) is smaller than the refractive index of the second refractive layer (RFL2), some of the reflected light (RL2) can be refracted at the first inclined surface (SP1) of the third aperture (OP3) and incident outside the light receiving region (RA) of the light receiving element (LRD). As a result, the sensing region (S2) of the light receiving element (LRD) can be reduced compared to the width of the sensing region (S) when the refractive layer (RFL) is not included. For example, if the thickness of the first refractive layer (RFL) is 3 μm and the first inclination angle (θ1) is 70°, the sensing region (S1) can be reduced to 747 μm.

[0158] Meanwhile, the second inclined surface (SP2) of the fourth aperture (OP4) also has a second inclined angle (θ2) that refracts incident light, and since the refractive index of the first refractive layer (RFL1) is smaller than the refractive index of the second refractive layer (RFL2), light emitted from a light-emitting element (LED) can be refracted when incident on the second inclined surface (SP2). Light directed toward the side direction of the display device (1000, see FIG. 1) can be reflected from the first inclined surface (SP1) and emitted toward the front direction of the display device (1000) (e.g., display surface (IS)). Accordingly, the front light efficiency of the display device (1000) can be increased. For example, the front light efficiency in the case of including a refractive layer (RFL) having a second inclined angle (θ2) can correspond to the fourth width (W4). At this time, the fourth width (W4) may be smaller than the third width (W3, see FIG. 5a). The frontal light efficiency corresponding to the fourth width (W4), which is smaller than the third width (W3), may be greater than the frontal light efficiency of the light-emitting element (LED) corresponding to the third width (W3).

[0159] The light-receiving region (RA) of the light-receiving element (LRD) may overlap with the first aperture (OP1) and the third aperture (OP3) in the thickness direction. Additionally, the light-emitting region (EA) of the light-emitting element (LED) may overlap with the second aperture (OP2) and the fourth aperture (OP4) in the thickness direction.

[0160] Other embodiments are described below. In the following embodiments, descriptions of components identical to those already described will be omitted or simplified, and the focus will be on the differences.

[0161] FIG. 7 is a cross-sectional view of a display device including a refractive layer according to another embodiment.

[0162] The embodiment illustrated in FIG. 7 differs from the embodiments illustrated in FIG. 5a to 6b, in that the angle of inclination of the cross-section of the third opening (OP3) and the angle of inclination of the cross-section of the fourth opening (OP4) are the same, in that the angle of inclination of the cross-section of the third opening (OP3) and the angle of inclination of the cross-section of the fourth opening (OP4) are different.

[0163] According to one embodiment, the first refractive layer (RFL1) can be formed through a photolithography process. A photoresist is applied to color filters (CF1, CF2), and after patterning by exposure and development, a first refractive layer (RFL1) having third and fourth apertures (OP3, OP4) can be formed using photocuring or the like. A structure in which the angle of inclination of the cross-section of the third aperture (OP3) and the angle of inclination of the cross-section of the fourth aperture (OP4) are different can be formed by varying the amount of exposure during the photolithography process.

[0164] As illustrated in FIG. 7, the cross-section of the third opening (OP3) may have a first inclined surface (SP1). In this case, the first inclined surface (SP1) may be symmetrical. The first inclined surface (SP1) may have a second inclination angle (θ2). The second inclination angle (θ2) may be an angle that refracts light incident on the first inclined surface (SP1) (e.g., reflected light reflected from an object (OBJ) in contact with the window (WIN)). For example, the second inclination angle (θ2) may be an angle greater than 57.2° and less than 90°. As a result, the sensing area (S2) of the light receiving element (LRD) may be reduced compared to the width of the sensing area (S, see FIG. 4) when the refractive layer (RFL) is not included.

[0165] The cross-section of the fourth opening (OP4) may have a second inclined surface (SP2). In this case, the second inclined surface (SP2) may be symmetrical. The second inclined surface (SP2) may have a first inclination angle (θ1). The first inclination angle (θ1) may be an angle that causes total reflection of light incident on the second inclined surface (SP2) (e.g., light emitted from a light-emitting element (LED)). For example, the first inclination angle (θ1) may be an angle greater than 0° and less than or equal to 57.2°. As a result, the frontal light efficiency of the display device (1000) may be increased. The frontal light efficiency when including a refractive layer (RFL) having the first inclination angle (θ1) may correspond to a third width (W3). In this case, the third width (W3) may be smaller than the second width (W2, see FIG. 4) which corresponds to the frontal light efficiency when the refractive layer (RFL) is not included. That is, the frontal light efficiency corresponding to a third width (W3) that is smaller than the second width (W2) can be greater than the frontal light efficiency of the light-emitting element (LED) corresponding to the second width (W2).

[0166] The light-receiving region (RA) of the light-receiving element (LRD) may overlap with the first aperture (OP1) and the third aperture (OP3) in the thickness direction. Additionally, the light-emitting region (EA) of the light-emitting element (LED) may overlap with the second aperture (OP2) and the fourth aperture (OP4) in the thickness direction.

[0167] In this way, by designing the angle of inclination of the cross-section of the third opening (OP3) and the angle of inclination of the cross-section of the fourth opening (OP4) differently, it is possible to achieve both optimization of the sensing area (S2) of the light receiving element (LRD) and optimization of the front light efficiency of the light emitting element (LED).

[0168] Generally, optimizing the frontal light efficiency of a light-emitting element (LED) may be advantageous in that the angle of inclination of the cross-section of the fourth aperture (OP4) has a first angle of inclination (θ1), thereby causing total reflection of light incident on the interface of the first refractive layer (RFL1) and the second refractive layer (RFL2).

[0169] Although not illustrated, contrary to the embodiment illustrated in FIG. 7, the cross-section of the third opening (OP3) may have a first inclination angle (θ1) and the cross-section of the fourth opening (OP4) may have a second inclination angle (θ2).

[0170] FIG. 8 is a cross-sectional view of a display device including a refractive layer according to another embodiment.

[0171] The embodiment illustrated in FIG. 8 differs from the embodiment illustrated in FIG. 5a and 5b, in that the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3) and the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth opening (OP4) are different, in that the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3) and the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth opening (OP4) are the same.

[0172] According to one embodiment, the first refractive layer (RFL1) can be formed through a photolithography process. A photoresist is applied to color filters (CF1, CF2), and after patterning by exposure and development, a first refractive layer (RFL1) having third and fourth apertures (OP3, OP4) can be formed using photocuring or the like. A structure in which the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third aperture (OP3) and the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth aperture (OP4) are different can be formed by applying the photolithography process twice.

[0173] As illustrated in FIG. 8, the cross-sections of the third and fourth openings (OP3, OP4) have a first inclination angle (θ1), and the thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3) may be greater than the thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth opening (OP4). However, this is not limited thereto, and the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3) may be smaller than the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth opening (OP4).

[0174] When the cross-section of the third opening (OP3) has a first inclination angle (θ1), the width of the sensing area (S3) can be reduced as the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3) increases between 0 and a preset value.

[0175] Referring to Table 1 below, when the refractive layer (RFL) is not included, that is, when the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third aperture (OP3) is 0 μm, the width of the sensing area (S) is 856 μm; when the first thickness (d1) is 2.05 μm, the width of the sensing area (S3) is 811 μm; when the first thickness (d1) is 3 μm, the width of the sensing area (S3) is 785 μm; when the first thickness (d1) is 4 μm, the width of the sensing area (S3) is 751 μm; when the first thickness (d1) is 5 μm, the width of the sensing area (S3) is 709 μm; and when the first thickness (d1) is 6 μm, the width of the sensing area (S3) is 654 μm. In this way, it can be seen that as the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third aperture (OP3) increases from 0 to 6 μm, the width of the sensing area (S3) decreases. However, the width of the sensing area (S3) corresponding to the first thickness (d1) described in Table 1 is an exemplary value and is not limited thereto.

[0177] First thickness (μm) 0 2.05 3 4 5 6 Sensing area (μm) 856 811 785 751 709 654

[0179] Meanwhile, even if the cross-section of the third opening (OP3) has a second inclination angle (θ2) which is not illustrated, the width of the sensing area (S3) can be reduced as the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3) increases between 0 and a preset value.

[0180] Referring to Table 2 below, when the refractive layer (RFL) is not included, that is, when the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third aperture (OP3) is 0 μm, the width of the sensing area (S) is 856 μm; when the first thickness (d1) is 2.05 μm, the width of the sensing area (S3) is 782 μm; when the first thickness (d1) is 3 μm, the width of the sensing area (S3) is 747 μm; when the first thickness (d1) is 4 μm, the width of the sensing area (S3) is 709 μm; when the first thickness (d1) is 5 μm, the width of the sensing area (S3) is 671 μm; and when the first thickness (d1) is 6 μm, the width of the sensing area (S3) is 632 μm. In this way, it can be seen that as the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third aperture (OP3) increases from 0 to 6 μm, the width of the sensing area (S3) decreases. However, the width of the sensing area (S3) corresponding to the first thickness (d1) described in Table 2 is an exemplary value and is not limited thereto.

[0182] First thickness (μm) 0 2.05 3 4 5 6 Sensing area (μm) 856 782 747 709 671 632

[0184] Referring to Tables 1 and 2 above, under the same conditions, the effect of reducing the width of the sensing area (S3) may be greater when the cross-section of the third opening (OP3) has a second inclination angle (θ2) than when the cross-section of the third opening (OP3) has a first inclination angle (θ1).

[0185] The cross-section of the fourth opening (OP4) may have a second inclined surface (SP2). In this case, the second inclined surface (SP2) may be symmetrical. The second inclined surface (SP2) may have a first inclination angle (θ1). The first inclination angle (θ1) may be an angle that causes total reflection of light incident on the second inclined surface (SP2) (e.g., light emitted from a light-emitting element (LED)). For example, the first inclination angle (θ1) may be an angle greater than 0° and less than or equal to 57.2°. As a result, the frontal light efficiency of the display device (1000) may be increased. The frontal light efficiency when including a refractive layer (RFL) having the first inclination angle (θ1) may correspond to a third width (W3). In this case, the third width (W3) may be smaller than the second width (W2, see FIG. 4) which corresponds to the frontal light efficiency when the refractive layer (RFL) is not included. That is, the frontal light efficiency corresponding to a third width (W3) that is smaller than the second width (W2) can be greater than the frontal light efficiency of the light-emitting element (LED) corresponding to the second width (W2).

[0186] In this way, by designing the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third aperture (OP3) and the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth aperture (OP4) differently, it is possible to achieve both optimization of the sensing area (S2) of the light receiving element (LRD) and optimization of the front light efficiency of the light emitting element (LED).

[0187] FIG. 9 is a cross-sectional view of a display device including a refractive layer according to another embodiment.

[0188] The embodiment illustrated in FIG. 9 differs from the embodiment illustrated in FIG. 5a to 6b, in that the angle of inclination of the cross-section of the third opening (OP3) and the angle of inclination of the cross-section of the fourth opening (OP4) are different, and the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3) and the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth opening (OP4) are different, in that the angle of inclination of the cross-section of the third opening (OP3) and the angle of inclination of the cross-section of the fourth opening (OP4) are the same, and the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3) and the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth opening (OP4) are the same.

[0189] According to one embodiment, the first refractive layer (RFL1) can be formed through a photolithography process. A photoresist is applied to color filters (CF1, CF2), and after patterning by exposure and development, a first refractive layer (RFL1) having third and fourth apertures (OP3, OP4) can be formed using photocuring or the like. A structure in which the angle of inclination of the cross-section of the third aperture (OP3) and the angle of inclination of the cross-section of the fourth aperture (OP4) are different can be formed by varying the amount of exposure during the photolithography process. A structure in which the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third aperture (OP3) and the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth aperture (OP4) are different can be formed by applying the photolithography process twice.

[0190] As illustrated in FIG. 9, the cross-section of the third opening (OP3) may have a first inclined surface (SP1). In this case, the first inclined surface (SP1) may be symmetrical. The first inclined surface (SP1) may have a second inclination angle (θ2). The second inclination angle (θ2) may be an angle that refracts light incident on the first inclined surface (SP1) (e.g., reflected light reflected from an object (OBJ) in contact with the window (WIN)). For example, the second inclination angle (θ2) may be an angle greater than 57.2° and less than 90°. As a result, the sensing area (S2) of the light receiving element (LRD) may be reduced compared to the width of the sensing area (S, see FIG. 4) when the refractive layer (RFL) is not included.

[0191] The cross-section of the fourth opening (OP4) may have a second inclined surface (SP2). At this time, the second inclined surface (SP2) may be symmetrical. The second inclined surface (SP2) may have a first inclination angle (θ1). The first inclination angle (θ1) may be an angle that causes total reflection of light incident on the second inclined surface (SP2) (e.g., light emitted from a light-emitting element (LED)). For example, the first inclination angle (θ1) may be an angle greater than 0° and less than or equal to 57.2°.

[0192] Additionally, the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth opening (OP4) may be greater than the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3). For example, the second thickness (d2) shown in FIG. 9 may be greater than the second thickness (d2) shown in FIG. 8.

[0193] As the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth aperture (OP4) increases between 0 and a preset value, the frontal light efficiency can be increased. For example, the second thickness (d2) can also be increased from 0 to 6 μm, just like the first thickness (d1), and as the second thickness (d2) increases from 0 to 6 μm, the frontal light efficiency can be increased.

[0194] As a result, the frontal light efficiency in the case of including a refractive layer (RFL) having a first inclination angle (θ1) and a second thickness (d2) can correspond to a fifth width (W5). In this case, the fifth width (W5) may be smaller than the third width (W3, see FIG. 8). That is, the frontal light efficiency of the light-emitting element (LED) shown in FIG. 9 may be greater than the frontal light efficiency of the light-emitting element (LED) shown in FIG. 8.

[0195] In this way, by designing the angle of inclination of the cross-section of the third opening (OP3), the angle of inclination of the cross-section of the fourth opening (OP4), the first thickness (d1) of the first refractive layer (RFL1) corresponding to the third opening (OP3), and the second thickness (d2) of the first refractive layer (RFL1) corresponding to the fourth opening (OP4) differently depending on the situation, it is possible to achieve both optimization of the sensing area (S2) of the light receiving element (LRD) and optimization of the front light efficiency of the light emitting element (LED).

[0196] Although the present invention has been described above with reference to embodiments thereof, those skilled in the art will understand that various modifications and changes can be made to the invention without departing from the spirit and scope of the invention as described in the following claims. Explanation of the symbols

[0197] 1000: Display device 100: Display panel PX: Pixel PHS: Light sensor PXC: Pixel circuit SSC: Sensor circuit T1~T7: Pixel transistors M1~M3: Sensor transistors LED: Light-emitting element LRD: Light-receiving element WIN: Window RFL1, RFL2: First and second refractive layers

Claims

Claim 1 A display device comprising: a base layer; a pixel layer disposed on the base layer and including a light-emitting element and a light-receiving element; an encapsulation layer covering the pixel layer; a black matrix disposed on the encapsulation layer and including a first opening corresponding to the light-receiving element and a second opening corresponding to the light-emitting element; a color filter disposed on the black matrix; a refractive layer disposed on the color filter and including a first refractive layer including a third opening corresponding to the first opening and a second refractive layer covering the first refractive layer; and a window disposed on the refractive layer; wherein the cross-section of the third opening has a first inclined surface. Claim 2 In claim 1, the first inclined surface is a display device having a first inclination angle that totally reflects reflected light reflected from an object in contact with the window. Claim 3 A display device according to claim 2, wherein a portion of the reflected light reflected by the first inclined surface is incident outside the light receiving area of ​​the light receiving element. Claim 4 A display device according to claim 2, wherein the first inclination angle is greater than 0° and less than or equal to 57.2°. Claim 5 In claim 1, the first inclined surface is a display device having a second inclined angle that refracts reflected light reflected from an object in contact with the window. Claim 6 A display device according to claim 5, wherein a portion of the reflected light refracted by the first inclined surface is incident outside the light receiving area of ​​the light receiving element. Claim 7 In claim 5, the display device wherein the second inclination angle is greater than 57.2° and less than 90°. Claim 8 A display device according to claim 1, wherein the refractive index of the first refractive layer is smaller than the refractive index of the second refractive layer. Claim 9 In claim 1, the width of the sensing area of ​​the light-receiving element is calculated by the following Equation 1, and the width of the sensing area is the width in the horizontal direction from the display surface of the window. [Equation 1] S = P + L1 / L2 (P + S0) (wherein S is the sensing area, P is the width of the first aperture, L1 is the vertical distance from the lower surface of the black matrix to the upper surface of the window, L2 is the vertical distance from the lower surface of the black matrix to the upper surface of the light-receiving element, and S0 is the width of the light-receiving element) Claim 10 delete Claim 11 A display device according to claim 9, wherein the width of the sensing area corresponding to the first inclination angle that totally reflects reflected light from an object in contact with the window is larger than the width of the sensing area corresponding to the second inclination angle that refracts the reflected light. Claim 12 delete Claim 13 A display device according to claim 9, characterized in that the thickness of the second refractive layer is greater than 0 μm and less than or equal to 6 μm. Claim 14 A display device according to claim 1, further comprising a touch sensor layer between the encapsulation layer and the black matrix. Claim 15 A display device according to claim 1, wherein the first refractive layer includes a fourth opening corresponding to the second opening, and the cross-section of the fourth opening has a second inclined surface. Claim 16 In claim 15, the second inclined surface is a display device having a third inclined angle that totally reflects the emitted light emitted from the light-emitting element or a fourth inclined angle that refracts the emitted light. Claim 17 A display device according to claim 16, wherein the third inclination angle is greater than 0° and less than or equal to 57.2°, and the fourth inclination angle is greater than 57.2° and less than 90°. Claim 18 In claim 15, a display device in which the angle of inclination of the first inclined surface and the angle of inclination of the second inclined surface are different. Claim 19 In claim 15, the thickness of the first refractive layer is different from the thickness of the region corresponding to the third opening and the thickness of the region corresponding to the fourth opening in a display device. Claim 20 In claim 15, a display device in which the horizontal width of the third opening is smaller than the horizontal width of the fourth opening.

Images