Display screen, fingerprint image acquisition method and display device

Abstract

The display screen, the fingerprint image acquisition method and the display device are provided, and the display screen comprises a substrate, a photosensitive element arranged on one side of the substrate, a pixel definition layer and a light-emitting layer, the pixel definition layer is arranged on a side of the photosensitive element away from the substrate, the pixel definition layer has a plurality of pixel openings, and the light-emitting layer is arranged at the pixel openings, a color film layer comprising a target color filter unit and a black matrix, the black matrix opposite to the photosensitive element is provided with an imaging hole, and a light-blocking structure is located between the photosensitive element and the target color filter unit and is configured to block a transmission path of target light between the target color filter unit and the photosensitive element, wherein the target light is ambient light passing through a fingerprint of a user's finger when the finger touches a fingerprint recognition area of the display screen.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of display, and in particular, to a display screen, a fingerprint image acquisition method and a display device. BACKGROUND

[0002] Fingerprint recognition is one of the important user authentication methods, which can be applied in fingerprint unlocking and fingerprint payment scenarios. With the development of fingerprint recognition technology, an in-screen fingerprint recognition scheme based on optical fingerprint recognition technology has emerged. In this scheme, the pixel circuit and the photosensitive element for fingerprint collection are manufactured on the same substrate, effectively reducing the thickness of the display screen with fingerprint recognition function and lowering the process manufacturing cost, making full-screen fingerprint recognition and folding screen fingerprint recognition possible, with the characteristics of short optical path and high transmittance compared with under-screen fingerprint recognition. However, this in-screen fingerprint recognition scheme still has some problems, for example, when using ambient light for fingerprint imaging, the phenomenon of blurred fingerprint imaging occurs. SUMMARY

[0003] In view of the above problems, the present disclosure is proposed to provide a display screen, a fingerprint image acquisition method and a display device which are beneficial to improve the above problems or at least partially improve the above problems.

[0004] In a first aspect, the embodiments of the present disclosure provide a display screen with fingerprint recognition function, comprising:

[0005] a substrate substrate;

[0006] a photosensitive element disposed on one side of the substrate substrate;

[0007] a pixel definition layer and a light emitting layer, the pixel definition layer is disposed on the side of the photosensitive element away from the substrate substrate, the pixel definition layer has a plurality of pixel openings, and the light emitting layer is disposed at the pixel openings;

[0008] a color film layer including a target color filter unit and a black matrix, the black matrix opposite to the photosensitive element is provided with an imaging hole;

[0009] a light shielding structure located between the photosensitive element and the target color filter unit, configured to block the transmission path of target light between the target color filter unit and the photosensitive element, wherein the target light is ambient light transmitted through the fingerprint of the user's finger when the user's finger touches the fingerprint recognition area of the display screen.

[0010] Further, the light shielding structure includes a blocking part between adjacent pixel openings in the pixel definition layer, and the material of the blocking part is a light shielding material to block the target light transmitted from the target color filter unit from being incident on the photosensitive element.

[0011] Further, a side wall of the blocking part has a preset slope angle, and the preset slope angle and a thickness of the blocking part in a direction perpendicular to the substrate substrate are set according to an incident angle of a first reference light, wherein the first reference light is a light ray in target light transmitted from the target color filter unit to the pixel defining layer, the light path of which points to a first critical imaging position of the photosensitive element, and the first critical imaging position is a critical imaging position relatively far away from the target color filter unit.

[0012] Further, the display screen further comprises a touch layer arranged between the light-emitting layer and the color film layer, the touch layer comprising a plurality of first touch electrodes extending along a first direction and a plurality of second touch electrodes extending along a second direction, the first touch electrodes and the second touch electrodes being in orthographic projection on the substrate substrate within the orthographic projection of the black matrix on the substrate substrate.

[0013] The light-shielding structure comprises the first touch electrode, and the first touch electrode is configured to block target light transmitted from the target color filter unit from being incident on the photosensitive element.

[0014] Further, a wire width of the first touch electrode, and / or a distance between the first touch electrode and the color film layer in a direction perpendicular to the substrate substrate is set according to an incident angle of a second reference light,

[0015] wherein the second reference light is a light ray in target light transmitted from the target color filter unit to the touch layer, the light path of which points to a second critical imaging position of the photosensitive element, and the second critical imaging position is a critical imaging position relatively close to the target color filter unit.

[0016] Further, in a direction perpendicular to the substrate substrate, an edge of the first touch electrode is flush with an edge of the corresponding black matrix.

[0017] In a second aspect, the embodiments of the present disclosure further provide a display screen with a fingerprint identification function, comprising:

[0018] a substrate substrate;

[0019] a light-emitting layer and a color film layer, the color film layer comprising a target color filter unit and a black matrix;

[0020] a fingerprint acquisition module comprising a photosensitive element and a signal acquisition module, the orthographic projection of the photosensitive element on the substrate substrate being within the orthographic projection of the black matrix on the substrate substrate;

[0021] The signal acquisition module is connected with the photosensitive element and is configured to: acquire a first fingerprint image and a second fingerprint image respectively, adjust pixel coordinates of the first fingerprint image, so that positions of the first fingerprint image and the second fingerprint image coincide, superimpose the first fingerprint image and the second fingerprint image after the adjustment, and obtain a target fingerprint image.

[0022] The first fingerprint image is an image formed on a photosensitive element on a first side of the target color filter unit by target light passing through the target color filter unit, the second fingerprint image is an image formed on a photosensitive element on a second side of the target color filter unit by target light passing through the target color filter unit, and the target light is ambient light passing through a fingerprint of a user's finger when the finger touches a fingerprint recognition area of the display screen.

[0023] Further, the light-emitting layer includes a red light-emitting device, a green light-emitting device, and a blue light-emitting device, and the fingerprint acquisition module further includes a light source for the green light-emitting device and the blue light-emitting device of the fingerprint recognition area. The photosensitive element has a protruding portion extending towards a spacing area between the green light-emitting device and the blue light-emitting device.

[0024] In a third aspect, the embodiments of the present disclosure further provide a fingerprint image acquisition method applied to a display screen with a fingerprint recognition function. The display screen includes a substrate, a photosensitive element, and a color film layer. The color film layer includes a target color filter unit and a black matrix. A normal projection of the photosensitive element on the substrate is located within a normal projection of the black matrix on the substrate. The method includes:

[0025] In response to a fingerprint touch operation of a user, a first fingerprint image and a second fingerprint image are acquired respectively. The first fingerprint image is an image formed on a photosensitive element on a first side of the target color filter unit by target light passing through the target color filter unit, and the second fingerprint image is an image formed on a photosensitive element on a second side of the target color filter unit by target light passing through the target color filter unit. The target light is ambient light passing through a fingerprint of a user's finger when the finger touches a fingerprint recognition area of the display screen.

[0026] Pixel coordinates of the first fingerprint image are adjusted so that positions of the first fingerprint image and the second fingerprint image coincide.

[0027] The first fingerprint image and the second fingerprint image after the adjustment are superimposed to obtain a target fingerprint image.

[0028] Further, adjusting pixel coordinates of the first fingerprint image so that positions of the first fingerprint image and the second fingerprint image coincide includes:

[0029] performing rotation and translation processing on the pixel coordinates of the first fingerprint image, so that the pixel coordinates of the first fingerprint image coincide with the pixel coordinates of the second fingerprint image.

[0030] In a fourth aspect, the present disclosure also provides a display device, including the display screen provided in the first aspect or the second aspect.

[0031] The technical solutions provided in the embodiments of the present disclosure have at least the following technical effects or advantages:

[0032] The display screen with the fingerprint identification function provided in the embodiments of the present disclosure has the imaging hole arranged in the black matrix opposite to the photosensitive element, and on the basis of collecting the target light entering from the imaging hole, the light shielding structure is further arranged to block the transmission path of the target light between the target color filter unit and the photosensitive element. The target light is the ambient light that passes through the fingerprint of the user's finger when the user's finger touches the fingerprint identification area of the display screen. In this way, when the ambient light is used for fingerprint imaging, the problem of fingerprint imaging blur caused by the target light incident from the target color filter unit can be effectively improved, thereby improving the clarity of the collected fingerprint image.

[0033] The above description is only a summary of the technical solutions provided in the embodiments of the present disclosure, in order to enable the technical means of the embodiments of the present disclosure to be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the embodiments of the present disclosure more obvious and easy to understand, the following specific embodiments of the present disclosure are described. BRIEF DESCRIPTION OF DRAWINGS

[0034] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description. The accompanying drawings are included to provide a description of preferred embodiments, and are not meant to limit the present disclosure. Moreover, the same reference numerals are used throughout the accompanying drawings to represent same or similar components. In the drawings:

[0035] Figure 1 is a schematic cross-sectional view of an exemplary display screen;

[0036] Figure 2 is a schematic light path diagram of the ambient light transmitted by the fingerprint;

[0037] Figure 3 is a schematic cross-sectional view of an exemplary display screen in the embodiments of the present disclosure;

[0038] Figure 4 is a schematic diagram of the blocking of the target light by the side wall of the blocking portion in the embodiments of the present disclosure;

[0039] Figure 5A design schematic of the blocking part in the embodiment of the present disclosure;

[0040] Figure 6 A schematic diagram of the first touch electrode shielding the target light in the embodiment of the present disclosure;

[0041] Figure 7 A design schematic of the touch electrode in the embodiment of the present disclosure;

[0042] Figure 8 A cross-sectional schematic diagram of another exemplary display screen in the embodiment of the present disclosure;

[0043] Figure 9 A light path diagram of the target light in the embodiment of the present disclosure imaging on the light-sensitive elements on both sides of the red filter unit;

[0044] Figure 10 An exemplary mixed light fingerprint image;

[0045] Figure 11 A fingerprint image collected by the left light-sensitive element;

[0046] Figure 12 A fingerprint image collected by the right light-sensitive element;

[0047] Figure 13 A target fingerprint image processed in the embodiment of the present disclosure;

[0048] Figure 14 A schematic diagram of the arrangement of the pixels and the light-sensitive elements in the embodiment of the present disclosure;

[0049] Figure 15 A flowchart of a fingerprint image acquisition method in the embodiment of the present disclosure. DETAILED DESCRIPTION

[0050] The most obvious structural feature of a fingerprint is the alternating ridge line and valley line, the ridge line being the raised part in the fingerprint texture, and the valley line being the recessed part in the fingerprint texture. For example, the following two ways can be adopted to acquire the fingerprint texture by using optical fingerprint sensing technology:

[0051] Firstly, ambient light transmission imaging. When a user's finger touches the fingerprint recognition area of the display screen, ambient light is irradiated onto the finger, and ridge transmission light (i.e. ambient light transmitted after irradiating onto the ridge in the fingerprint) and valley transmission light (i.e. ambient light transmitted after irradiating onto the valley in the fingerprint) are obtained. The light intensities of the ridge transmission light and the valley transmission light are different, and after the ridge transmission light and the valley transmission light are collected, a fingerprint image with alternating bright and dark parts can be formed according to the ridge transmission light and the valley transmission light.

[0052] The second kind is to display light reflection imaging. By collecting the light reflected after the display light irradiating into the ridge of the fingerprint and the light reflected after the display light irradiating into the valley of the fingerprint, the image of the fingerprint with light and shade is obtained.

[0053] As shown in Figure 1 some examples, the display screen with in-screen fingerprint identification function can include: a substrate 100, a photosensitive element 102 arranged on one side of the substrate 100, a pixel defining layer 104 and a light emitting layer 106 arranged on the side of the photosensitive element 102 away from the substrate 100, and a color film layer 110 arranged on the side of the light emitting layer 106 away from the photosensitive element 102. The light emitting layer 106 is arranged at the pixel opening of the pixel defining layer 104, and the color film layer 110 includes a plurality of color filter units 111 and a black matrix 112 arranged between adjacent color filter units 111.

[0054] The orthographic projection of the photosensitive element 102 on the substrate 100 is located in the orthographic projection of the black matrix 112 on the substrate 100. The black matrix 112 directly opposite the photosensitive element 102 is provided with an opening as an imaging hole 113 for imaging the fingerprint. The size ratio of the photosensitive element 102 and the directly opposite black matrix 112 realizes the effect of micro-collimation, so that the photosensitive element 102 can receive the light carrying fingerprint information from the ambient light transmission or display light reflection through the imaging hole 113.

[0055] For example, when using ambient light for fingerprint imaging, the ambient light transmitted through the finger can be incident on the photosensitive element 102 through the imaging hole 113 for imaging to obtain a fingerprint image. However, in actual application, it is found that under ambient light, the phenomenon of blurred fingerprint imaging occurs. For this reason, through actual verification analysis and data verification, it is found that the cause of mixed light is that when using ambient light for fingerprint imaging, as shown in Figure 2 the light transmitted through the finger will have a larger part transmitted from the red filter unit 111a above the light emitting layer 106 in addition to the imaging hole 113 of the black matrix 112 above the photosensitive element 102 as expected. Since the ambient light transmitted through the finger is usually red light, the red light can pass through the red filter unit 111a therein without being affected in terms of spectral transmission, but the opening of the red filter unit 111a is relatively large, resulting in a high amount of light collected. Therefore, when using ambient light for fingerprint imaging, two images generated by the light transmitted through the red filter unit 111a will appear, resulting in blurred fingerprint imaging.

[0056] Therefore, the present disclosure provides two solutions. One solution is to use the imaging hole 113 for fingerprint imaging and shield the transmission light of the large-angle oblique red filter unit 111a. The other solution is to abandon the design of the hole on the black matrix 112 directly opposite the photosensitive element 102 and only use the ambient light obliquely incident through the red filter unit 111a for fingerprint imaging. Both solutions can effectively improve the imaging blur problem caused by mixed light during ambient light fingerprint imaging, thereby improving the clarity of the collected fingerprint image.

[0057] Exemplary embodiments of the present disclosure will be described in greater detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be accurately conveyed to those skilled in the art.

[0058] It should be noted that the term "and / or" appearing in the present document merely describes an association relationship of associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. The term "multiple" includes two or more cases.

[0059] An embodiment of the present disclosure provides a display screen with a fingerprint recognition function. For example, the display screen can be a display panel, a smart display screen, or other display products or components with a fingerprint recognition function.

[0060] The display screen includes a plurality of pixel regions, each pixel region including a plurality of sub-pixels, each sub-pixel emitting light of one color, such as one of red, green, blue, and white. The number and arrangement of sub-pixels provided in each pixel region can be set as needed, and the present embodiment does not limit this. For example, each pixel region can include three sub-pixels, which are red, green, and blue sub-pixels, respectively. For another example, each pixel region can also include four sub-pixels, which are white, red, green, and blue sub-pixels, respectively; or, which are red, blue, and two green sub-pixels, respectively.

[0061] The display screen includes a fingerprint recognition region, for example, the fingerprint recognition region can be located in the active display area (AA area) of the display screen. When a user's finger touches the fingerprint recognition region, the display screen can collect the user's fingerprint image, thereby realizing the fingerprint recognition function.

[0062] Figure 3 A cross-sectional schematic view of an exemplary display screen is shown. As Figure 3As shown, the display screen 10 can include a substrate 100, a photosensitive element 102, a pixel define layer 104 (PDL), a light emitting layer 106, a color film layer 110, and a light shielding structure.

[0063] For example, the substrate 100 can be a rigid substrate such as a glass substrate or a PMMA (Polymethylmethacrylate) substrate, or can also be a flexible substrate such as an ultra-thin glass, a PET (Polyethylene terephthalate) substrate, a PEN (Polyethylenenaphthalate two formic acid glycol ester) substrate, or a PI (Polyimide) substrate, and the like, which is not limited in the present embodiment.

[0064] The photosensitive element 102 is disposed on one side of the substrate 100. For example, the photosensitive element 102 can be an amorphous silicon (a-Si) PIN photosensitive diode, or other elements having the function of converting optical signals into electrical signals.

[0065] It should be noted that the side of the photosensitive element 102 close to the substrate 100 is also provided with a thin film transistor array and related functional film layers such as a buffer layer and / or an insulating layer, etc. For example, the thin film transistor array can include a drive transistor 122 and a photosensitive control transistor 121, the drive transistor 122 is connected with the light emitting device of the corresponding sub-pixel, and the photosensitive control transistor 121 is connected with the photosensitive element 102 and is configured to control the output of the electrical signal converted by the photosensitive element 102. For example, when the photosensitive control transistor 121 is turned on, the electrical signal converted by the light signal collected by the photosensitive element 102 is output through the photosensitive control transistor 121.

[0066] In some examples, the photosensitive element 102 is distributed in the fingerprint recognition area. For example, at least one photosensitive element 102 is disposed in each pixel area in the fingerprint recognition area. That is, one photosensitive element 102 can be disposed in each pixel area, or a plurality of photosensitive elements 102 can also be disposed in each pixel area, which is set according to actual needs. Of course, in other examples, the photosensitive element 102 can also be disposed in other display areas as needed in addition to being distributed in the fingerprint recognition area, which is not limited in the present embodiment.

[0067] The pixel defining layer 104 is disposed on the side of the light sensitive element 102 away from the substrate 100. The pixel defining layer 104 has a plurality of pixel openings for defining the light emitting area of each sub-pixel.

[0068] The light emitting layer 106 is located in the pixel openings and includes a plurality of light emitting devices. Each sub-pixel includes one light emitting device. Taking the example of a pixel area including a red sub-pixel, a green sub-pixel and a blue sub-pixel, the light emitting layer 106 can include a red light emitting device, a blue light emitting device and a green light emitting device.

[0069] The light emitting device can include a first electrode layer, a light emitting material layer and a second electrode layer stacked together, the first electrode layer and the second electrode layer serving as the anode 103 and the cathode respectively. For example, the first electrode layer can be the anode 103 and the second electrode layer can be the cathode. In addition, the light emitting device can further include a functional material layer, such as a hole injection layer, a hole transport layer, an electron injection layer and an electron transport layer, disposed between the anode 103 and the light emitting material layer, and between the cathode and the light emitting material.

[0070] The light emitting material layer can employ a variety of light emitting materials. For example, the light emitting material can include an organic material, in which case the light emitting device can be an OLED (Organic Light Emitting Diode) light emitting device. For another example, the light emitting material can include a quantum dot material, in which case the light emitting device can be a QLED (Quantum Dot Light Emitting Diodes) light emitting device.

[0071] Of course, the display screen further includes a thin film encapsulation layer 130 (TFE) disposed on the side of the light emitting layer 106 away from the substrate 100, which can protect the light emitting layer 106 and achieve planarization.

[0072] The color filter layer 110 is disposed on the side of the thin film encapsulation layer 130 away from the light emitting layer 106, i.e., a COE (Color filter On Encapsulation) structure is adopted, so that no polarizer needs to be additionally disposed, reducing the thickness of the screen.

[0073] The color filter layer 110 includes a plurality of color filter units 111 and a black matrix 112. The color filter units 111 are arranged correspondingly to the light emitting devices. Taking the plurality of light emitting devices including a red light emitting device, a blue light emitting device and a green light emitting device as an example, the color filter units 111 also include a red filter unit 111a, a blue filter unit and a green filter unit correspondingly. The photosensitive element 102 is arranged correspondingly to the black matrix 112, and the black matrix 112 opposite to the photosensitive element 102 is provided with an imaging hole 113. When performing fingerprint identification, the light reflected or transmitted by the finger can enter the photosensitive element 102 through the imaging hole 113 to form an image.

[0074] In the scenario of using ambient light for fingerprint imaging, when the user's finger touches the fingerprint identification area of the display screen, the ambient light transmitted through the fingerprint of the finger is referred to as target light. Part of the target light can pass through the imaging hole 113 on the black matrix 112 and enter the corresponding photosensitive element 102 to form an image. Another part can pass through the color filter unit 111 of the corresponding color and continue to enter the screen. The color filter unit 111 capable of transmitting the above-mentioned target light is referred to as a target color filter unit herein. For example, the target light is red light, and the target color filter unit is a color filter unit 111 capable of transmitting red light. Taking the color filter unit 111 including a red filter unit, a blue filter unit and a green filter unit as an example, the target color filter unit is a red filter unit. The target color filter unit is mainly taken as a red filter unit for illustration herein.

[0075] The light shielding structure is located between the photosensitive element 102 and the target color filter unit. The light shielding structure is configured to block the transmission path of the target light between the target color filter unit and the photosensitive element 102. In this way, the target light incident at a large angle from the target color filter unit can be shielded, and it is ensured that the target light transmitted through the target color filter unit will not irradiate on the photosensitive element 102, and the fingerprint imaging is performed using the imaging hole 113 opposite to the photosensitive element 102, thereby improving the problem of blurred fingerprint imaging caused by the mixed light of the target light incident from the target color filter unit and the target light incident from the imaging hole 113, and being beneficial to improving the clarity of the collected fingerprint image.

[0076] In some examples, the light-shielding structure may include a blocking portion 1041 located between adjacent pixel openings in the pixel defining layer 104. By designing the material and structural parameters of the blocking portion 1041, it is possible to effectively block target light transmitted from the target color filter unit from entering the photosensitive element 102. In this case, the material of the pixel defining layer 104 is a light-shielding material, that is, the material of the blocking portion 1041 is a light-shielding material. For example, in actual processing, after the anode 103 layer of the light-emitting device is prepared, the pixel defining layer 104 can be prepared on the anode 103 layer using a black light-shielding material to form a blocking portion 1041 that can block the target light incident at a large angle.

[0077] For example, considering the limitations of the pixel defining layer 104 manufacturing process, and to better block large-angle target light rays transmitted from the target color filter unit, the sidewall of the blocking portion 1041 can be an arc surface convex toward the pixel opening direction. Of course, in other examples, the sidewall of the blocking portion 1041 can also be an inclined plane or other non-planar surface, and this embodiment does not limit this.

[0078] like Figure 4 As shown, the sidewall of the blocking part 1041 has a preset slope angle. By configuring the slope angle and the thickness of the blocking part 1041 in the direction perpendicular to the substrate 100, the target light transmitted from the target color filter unit and incident on the photosensitive element 102 can be blocked.

[0079] For example, such as Figure 5 As shown, the closer the incident light is to the right side of the red filter unit 111a, the more easily it is blocked by the aforementioned blocking part 1041. The light incident from the left side is the easiest to bypass the blocking part 1041 and enter the photosensitive element 102. It can be understood that the photosensitive element 102 has an effective imaging area, that is, the area that can collect the incident target light. It has two critical imaging positions relative to the red filter unit 111a, located on both sides of the effective imaging area. In this paper, the critical imaging position relatively far away from the red filter unit 111a is called the first critical imaging position P1, and the critical imaging position relatively close to the red filter unit 111a is called the second critical imaging position P2.

[0080] Therefore, the target light rays incident at a large angle from the first incident light position of the red filter unit 111a onto the pixel defining layer 104 can illuminate the photosensitive element 102 in two critical situations: one is pointing to the first critical imaging position P1 of the photosensitive element 102, such as... Figure 5 Another type of ray is ray 2, which points to the second critical imaging position P2 of the photosensitive element 102, such as... Figure 5 The light ray 1 in the light source. The first incident light position is the critical incident light position near the side of the corresponding photosensitive element 102.

[0081] In some examples, considering that the touch layer 140 also has a certain shielding effect on the target light when the display screen also has a touch function, assuming that the touch layer 140 has a shielding function of h0 microns, for the light-sensitive element 102 located on the left side of the red filter unit 111a, considering the shielding of the touch layer 140, the first light entry position is Q1 point in the following figure. Figure 5 At this time, for the target light incident from the left side of the red filter unit 111a and not shielded by the touch layer 140, the incident angle can be calculated by the following method respectively:

[0082] For light 1, the incident angle A can be obtained by A = arctan(b / (h-h0)), where b represents the distance between the opening of the black matrix 112 corresponding to the red filter unit 111a and the imaging hole 113 along the first direction (i.e. the x direction in the figure), and h represents the spacing between the anode 103 and the black matrix 112 along the direction perpendicular to the substrate 100 (i.e. the z direction in the figure).

[0083] For light 2, the incident angle B can be obtained by B = arctan((b+k) / (h-h0)), where k represents the effective imaging surface width of the light-sensitive element 102 along the first direction. It can be considered that the blocking part 1041 only needs to shield the above-mentioned light 2, that is, the large-angle target light incident on the light-sensitive element 102.

[0084] That is, the above-mentioned light 2 can be taken as the first reference light. The slope angle of the side wall of the blocking part 1041 and the thickness of the blocking part 1041 can be set according to the incident angle B of the above-mentioned light 2, that is, determined according to the above-mentioned b, k, h and h0.

[0085] For example, if the touch metal layer has a thickness of 6500 angstroms along the direction perpendicular to the substrate 100, and the spacing between the touch metal layer and the black matrix 112 is 3000 angstroms, it can be considered that the touch metal layer has a shielding function of 1 micron, h0 = 1 micron, and h = 15 microns, b = 13.5 microns, k = 6 microns, then the incident angle of the above-mentioned light 2 is arctan(19.5 / 14) = 54°. At this time, the slope angle C of the side wall of the blocking part 1041 can be set to 60°, and the thickness of the blocking part 1041 can be set to 7 microns. Of course, the above-mentioned slope angle and thickness can also be within an acceptable error range, and can meet the requirements of the required fingerprint imaging quality.

[0086] In some examples, the display screen further comprises a touch layer 140, so that the display screen also has a touch function. The touch layer 140 is arranged between the light-emitting layer 106 and the color film layer 110, and can be arranged between the above-mentioned encapsulation layer and the color film layer 110.

[0087] The touch layer 140 includes a plurality of first touch electrodes 141 extending along a first direction and a plurality of second touch electrodes 142 extending along a second direction. The first direction and the second direction intersect. For example, the first direction is the x-direction of the display screen, and the second direction is the y-direction of the display screen. The orthographic projections of the first touch electrodes 141 and the second touch electrodes 142 on the substrate 100 lie within the orthographic projection of the aforementioned black matrix 112 on the substrate 100, and the first touch electrodes 141 and the second touch electrodes 142 are insulated from each other.

[0088] At this time, the light-shielding structure may include: the first touch electrode 141 described above. For example... Figure 6 As shown, in addition to providing touch functionality, the first touch electrode 141 is also configured to block target light transmitted from the target color filter unit from entering the photosensitive element 102.

[0089] For example, based on meeting the design requirements of the touch function, the first touch electrode 141 can be widened, and / or the distance between the first touch electrode 141 and the color filter layer 110 in the direction perpendicular to the substrate 100 can be increased to block the large-angle target light rays that pass through the target color filter unit and are incident on the photosensitive element 102.

[0090] In some examples, the traces of the first touch electrode 141 can be widened so that the edge of the first touch electrode 141 is flush with the edge of the corresponding black matrix 112 along the direction perpendicular to the substrate 100, so as to better block the target light incident at a large angle.

[0091] For example, such as Figure 7 As shown, when designing the target light blocking for the first touch electrode 141, it is only necessary to block the target light that might illuminate the photosensitive element 102 transmitted from the second light-incident position of the red filter unit 111a. This will block the large-angle target light incident on the photosensitive element 102. The second light-incident position is the critical light-incident position away from the corresponding photosensitive element 102, such as... Figure 7 The Q2 position is located to the right of the red filter unit 111a.

[0092] At this time, for light rays 3 and 4 incident from the second incident position toward the first critical imaging position P1 and the second critical imaging position P2 of the corresponding photosensitive element 102, the incident angle can be calculated as follows:

[0093] The incident angle A1 of the light ray 3 can be obtained by the formula: A1=arctan(b1 / h), and the incident angle B1 of the light ray 4 can be obtained by the formula: B1=arctan(b2 / h). Wherein, b1 is the distance between the second light-in position and the second critical imaging position P2 along the first direction, i.e., the x direction in the figure; and b2 is the distance between the second light-in position and the first critical imaging position P1 along the first direction, i.e., the x direction in the figure.

[0094] Therefore, the target light ray of the A1 angle can be shielded to achieve the shielding of the large-angle target light ray. That is, the light ray 3 can be taken as the second reference light ray, and the width of the trace of the first touch electrode 141 and / or the distance between the first touch electrode 141 and the color filter layer 110 in the direction perpendicular to the substrate 100 can be set according to the incident angle of the light ray 3, i.e., according to b1 and h.

[0095] For example, if the black matrix 112 opening size b11 of the red filter unit 111a is 33.5 microns, the black matrix 112 width b12 between the black matrix 112 opening and the imaging hole 113 is 13.5 microns, k is 6 microns, and h1 is 15 microns, then b1=b11+b12=47 microns, and b2=b1+k=53 microns. Then, A1 is 72°, and B1 is 74°. At this time, the trace of the first touch electrode 141 can be widened to be flush with the corresponding black matrix 112, and the distance D between the first touch electrode 141 and the color filter layer 110 in the direction perpendicular to the substrate 100 can be set to 10.7 microns, so as to achieve the shielding of the large-angle target light ray incident from the red filter unit 111a while meeting the touch function.

[0096] For example, the distance of the first touch electrode 141 relative to the color filter layer 110 in the direction perpendicular to the substrate 100 can be adjusted, for example, by moving the bottom surface position of the first touch electrode 141 downward to increase the distance D between the first touch electrode 141 and the color filter layer 110 in the direction perpendicular to the substrate 100, so as to increase the shielding of the large-angle incident target light ray.

[0097] It should be noted that the above light shielding structure can include the above blocking part 1041 and / or the above first touch electrode 141. That is, both of the above two schemes can achieve the shielding of the large-angle target light ray incident from the target color filter unit, and the two schemes can be applied separately in products or together in products, and the present embodiment does not limit the same.

[0098] Of course, in addition to the above structure, the display screen can also include other structures, for example, also includes a cover layer (not shown in the figure), which is arranged on the side of the color film layer 110 away from the substrate 100, for protecting the color film layer 110, which can be referred to in the related art.

[0099] The embodiment of the present disclosure improves the original hierarchical structure in the display screen, so that it can block the large-angle target light rays transmitted from the target color filter unit, so as to improve the problem of blurred fingerprint imaging caused by the target light rays incident on the photosensitive element 102, and is conducive to improving the clarity of the collected fingerprint image.

[0100] An embodiment of the present disclosure also provides a display screen with a fingerprint recognition function, for example, the display screen can be a display panel, a smart display screen, or other display products or components with a fingerprint recognition function. As shown in Figure 8 The display screen 20 includes a substrate 100, a pixel definition layer 104, a light-emitting layer 106, a color film layer 110, and a fingerprint collection module.

[0101] The color film layer 110 includes a plurality of color filter units 111 and a black matrix 112. Among the plurality of color filter units 111, the color filter unit 111 capable of transmitting the target light rays is referred to as a target color filter unit.

[0102] The fingerprint collection module includes a photosensitive element 102 and a signal collection module. The orthogonal projection of the photosensitive element 102 on the substrate 100 is located within the orthogonal projection of the black matrix 112 on the substrate 100. Unlike the embodiments provided above, the black matrix 112 directly opposite the photosensitive element 102 in this embodiment is not provided with the imaging hole 113. At this time, when using ambient light for fingerprint imaging, the fingerprint imaging light rays come from the target light rays transmitted through the target color filter unit and incident at a large angle. The target light rays transmitted through the target color filter unit are respectively incident on the photosensitive elements 102 on both sides for fingerprint imaging.

[0103] For example, as shown in Figure 9 The target light rays carrying fingerprint information will be imaged on the photosensitive elements 102a and 102b on both sides after transmitting through the red filter unit 111a, thereby causing the collected fingerprint image to have two overlapping images, as shown in Figure 10 The light signals collected by the photosensitive elements 102a and 102b on both sides of the red filter unit 111a are extracted into separate fingerprint images, Figure 11 The fingerprint image collected by the left photosensitive element 102a is shown, Figure 12 The fingerprint image collected by the right photosensitive element 102b is shown. By comparing Figure 11 and Figure 12It is found that the images formed on the two sides are the same, but there is a positional deviation in the imaging position, resulting in the misalignment of the two images and ghosting, affecting the clarity of the fingerprint image.

[0104] Therefore, according to the relative position relationship of the two images, the coordinate conversion is performed before superposition, which can improve the imaging blur problem caused by misalignment, and the signal quantity after brightness superposition is twice that of a single fingerprint image, which can effectively improve the signal-to-noise ratio of the collected fingerprint image, thereby obtaining a clearer fingerprint image.

[0105] Based on this, the image formed on the photosensitive element on the first side of the target color filter unit by the target light passing through the target color filter unit is referred to as the first fingerprint image, and the image formed on the photosensitive element on the second side of the target color filter unit by the target light passing through the target color filter unit is referred to as the second fingerprint image. The first side and the second side are opposite sides, for example, if the first side is the left side in Figure 9 , the second side is the right side in Figure 9 , if the first side is the right side in Figure 9 , then the second side is the left side in Figure 9 , and the present embodiment does not limit this.

[0106] The above signal acquisition module is connected with the photosensitive element 102 and is configured to acquire the first fingerprint image and the second fingerprint image, and then adjust the pixel coordinates of the first fingerprint image so that the positions of the first fingerprint image and the second fingerprint image coincide. Then, the adjusted first fingerprint image and the second fingerprint image are superimposed to obtain the target fingerprint image.

[0107] In specific implementation, the signals collected by the photosensitive elements on the first side of each target color filter unit and the signals collected by the photosensitive elements on the second side of each target color filter unit can be acquired respectively. The signals collected by the photosensitive elements on the first side are spliced to obtain the first fingerprint image, and the signals collected by the photosensitive elements on the second side are spliced to obtain the second fingerprint image.

[0108] After the first fingerprint image and the second fingerprint image are acquired, the misaligned first fingerprint image and the second fingerprint image can be positionally corrected. For example, the positional relationship of the two can be determined and configured in advance, and then the pixel coordinates of the first fingerprint image are rotated and translated according to the preset positional relationship, so that the positions of the first fingerprint image and the second fingerprint image coincide. For example, the preset positional relationship can include a rotation matrix and a translation matrix, and the pixel coordinates of the first fingerprint image are adjusted according to the rotation matrix and the translation matrix, so that the pixel coordinates of the first fingerprint image coincide with the pixel coordinates of the second fingerprint image.

[0109] After the position adjustment is completed, the pixel values of the first fingerprint image and the pixel values of the second fingerprint image can be superimposed to obtain a target fingerprint image. That is, for each pixel, the pixel value of the first fingerprint image is superimposed with the pixel value in the second fingerprint image, and the superimposed pixel value is taken as the pixel value of the pixel in the target fingerprint image, effectively improving the signal-to-noise ratio of the ambient light fingerprint image. For example, after superimposition by the coordinate conversion shown in Figure 11 and Figure 12 The target fingerprint image obtained after superimposition is shown in Figure 13 , which effectively improves the definition compared with the image shown in Figure 10 .

[0110] On this basis, in order to ensure that a fingerprint image can still be formed under low ambient light, the display screen provided by the embodiments of the present disclosure also has a display light imaging function. When it is detected that the ambient light brightness is lower than a preset threshold, it is determined that the ambient light brightness is too low, and the display light fingerprint imaging mode is started, that is, the light reflected by the display light irradiated on the fingerprint is used for fingerprint imaging.

[0111] At this time, the fingerprint collection module further includes a light source. For example, part of the light emitting devices distributed in the fingerprint recognition area can be reused as the light source for display light fingerprint imaging. In some examples, the light emitting layer 106 includes red light emitting devices, green light emitting devices, and blue light emitting devices. Considering that the ambient light that transmits through the finger is usually red light, the green light emitting devices and the blue light emitting devices in the fingerprint recognition area can be reused as the light source for display light fingerprint imaging, so as to suppress the influence of ambient light. Accordingly, the fingerprint reflected light transmitted from the blue filter unit and the green filter unit can be used for fingerprint imaging.

[0112] Further, as shown in Figure 14 , the photosensitive element 102 also has a protruding portion 1021 that extends towards the spacing area between the green light emitting devices and the blue light emitting devices, away from the red filter unit 111a. The shape and area of the protruding portion 1021 can be set according to actual needs, for example, the shape can be square, such as adding a 6 microns*6 microns or 10 microns*10 microns area, or the shape can also be circular, which is not limited in the embodiments.

[0113] For example, as shown in Figure 14 , each pixel area 200 of the display screen can include one red sub-pixel R, two green sub-pixels G, and one blue sub-pixel B. Each pixel area 200 can be provided with one photosensitive element 102, which can be arranged between the red sub-pixel R and the blue sub-pixel B. That is, the photosensitive element 102 is arranged opposite to the black matrix 112 between the red sub-pixel R and the blue sub-pixel B. The photosensitive element 102 can be provided with the protruding portion 1021 described above between the upper green sub-pixel G and the blue sub-pixel B (such asFigure 14 The convex portion 1021 can be arranged between the green sub-pixel G and the blue sub-pixel B, or the convex portion 1021 can be arranged between the green sub-pixel G and the blue sub-pixel B on the lower side, or the convex portion 1021 can be arranged between the green sub-pixel G and the blue sub-pixel B on the upper side, or the convex portion 1021 can be arranged between the green sub-pixel G and the blue sub-pixel B on the lower side and the upper side, and the present embodiment is not limited in this regard.

[0114] By increasing the area of the photosensitive element 102 and adding the area between the blue sub-pixel B and the green sub-pixel G, the small imaging area can form a micro-collimation effect with the blue filter unit and the green filter unit. In this way, the display light intensity can be utilized to the greatest extent, the light efficiency of the fingerprint reflection can be improved, the influence of the ambient light can be suppressed, and a clear fingerprint image can be formed.

[0115] In addition, an embodiment of the present disclosure further provides a fingerprint image acquisition method applied to a display screen with a fingerprint recognition function. The display screen comprises a substrate 100, a photosensitive element 102, a light-emitting layer 106, and a color film layer 110, wherein the color film layer 110 comprises a target color filter unit and a black matrix 112; the orthographic projection of the photosensitive element 102 on the substrate 100 is located in the orthographic projection of the black matrix 112 on the substrate 100. The specific structure can refer to the related description in the above embodiment, and will not be described here again. As shown in the figure, the method can comprise: Figure 15

[0116] Step S101, in response to a fingerprint touch operation of a user, acquiring a first fingerprint image and a second fingerprint image respectively;

[0117] Step S102, adjusting the pixel coordinates of the first fingerprint image so that the first fingerprint image and the second fingerprint image are coincident in position;

[0118] Step S103, superimposing the adjusted first fingerprint image and the second fingerprint image to obtain a target fingerprint image.

[0119] The first fingerprint image is an image formed by a target light ray passing through the target color filter unit on the photosensitive element on the first side of the target color filter unit, and the second fingerprint image is an image formed by the target light ray passing through the target color filter unit on the photosensitive element on the second side of the target color filter unit. The target light ray is the ambient light passing through the fingerprint of the user's finger when the user's finger touches the fingerprint recognition area of the display screen.

[0120] It should be noted that the specific implementation process of steps S101 to S103 can refer to the related description in the above embodiment, and will not be described here again.

[0121] ​In some examples, the process of adjusting the pixel coordinates of the first fingerprint image so that the positions of the first fingerprint image and the second fingerprint image coincide can include: performing rotation and translation processing on the pixel coordinates of the first fingerprint image so that the positions of the first fingerprint image and the second fingerprint image coincide. The specific implementation process can refer to the related description in the foregoing embodiments, and will not be described here again.

[0122] In addition, an embodiment of the present disclosure further provides a display device, including the display screen provided in any one of the foregoing embodiments. For example, the display device can be a mobile phone, a notebook computer, a tablet computer, a display, a television, a digital photo frame, or any product or component having a display function.

[0123] It should be noted that each of the embodiments provided by the present disclosure is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other.

[0124] In the foregoing description, the technical details such as the composition of each layer of the product are not described in detail. However, those skilled in the art should understand that the layers, regions, etc. of the required shape can be formed by various technical means. In addition, those skilled in the art can also design methods that are not exactly the same as the methods described above in order to form the same structure. Although each embodiment is described above, this does not mean that the measures in each embodiment cannot be used advantageously in combination.

[0125] In addition, those skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the present disclosure is limited to these examples; under the idea of the present disclosure, the above embodiments or technical features in different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes of different aspects of one or more embodiments of the present disclosure as described above. In order to be brief, they are not provided in detail.

[0126] Although the preferred embodiments of the present disclosure have been described, those skilled in the art can make further changes and modifications to the embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to include the preferred embodiments and all changes and modifications falling within the scope of the present disclosure.

Claims

1. A display screen with a fingerprint recognition function, characterized in that, The display screen comprises a substrate, a light-emitting layer, and a color filter layer, the color filter layer comprising a target color filter unit and a black matrix, a fingerprint collection module comprising a photosensitive element and a signal collection module, a normal projection of the photosensitive element on the substrate being located within a normal projection of the black matrix on the substrate, the signal collection module being connected to the photosensitive element and being configured to acquire a first fingerprint image and a second fingerprint image respectively, to perform pixel coordinate adjustment on the first fingerprint image so that the first fingerprint image and the second fingerprint image are overlapped in position, to superimpose the adjusted first fingerprint image and the second fingerprint image to obtain a target fingerprint image, wherein the first fingerprint image is an image formed by target light passing through the target color filter unit on a photosensitive element on a first side of the target color filter unit, the second fingerprint image is an image formed by target light passing through the target color filter unit on a photosensitive element on a second side of the target color filter unit, and the target light is ambient light passing through a fingerprint of a user's finger when the finger touches a fingerprint recognition area of the display screen. The light-emitting layer comprises a red light-emitting device, a green light-emitting device, and a blue light-emitting device, the fingerprint collection module further comprises a light source, the light source being the green light-emitting device and the blue light-emitting device of the fingerprint recognition area, and the photosensitive element has a protruding portion extending towards a spacing area between the green light-emitting device and the blue light-emitting device. The display screen comprises a substrate, a light-emitting layer, and a color filter layer, the color filter layer comprising a target color filter unit and a black matrix, a fingerprint collection module comprising a photosensitive element and a signal collection module, a normal projection of the photosensitive element on the substrate being located within a normal projection of the black matrix on the substrate, the method comprising: in response to a fingerprint touch operation of a user, acquiring a first fingerprint image and a second fingerprint image respectively, the first fingerprint image being an image formed by target light passing through the target color filter unit on a photosensitive element on a first side of the target color filter unit, the second fingerprint image being an image formed by target light passing through the target color filter unit on a photosensitive element on a second side of the target color filter unit, and the target light being ambient light passing through a fingerprint of a user's finger when the finger touches a fingerprint recognition area of the display screen; performing pixel coordinate adjustment on the first fingerprint image so that the first fingerprint image and the second fingerprint image are overlapped in position; superimposing the adjusted first fingerprint image and the second fingerprint image to obtain a target fingerprint image. The pixel coordinate adjustment on the first fingerprint image so that the first fingerprint image and the second fingerprint image are overlapped in position comprises:

2. The display screen of claim 1, wherein, performing rotation and translation processing on the pixel coordinates of the first fingerprint image so that the first fingerprint image and the second fingerprint image are overlapped in position.

3. A method of acquiring a fingerprint image, characterized by, The display screen of claim 1 or 2. ​ ​ ​ 4. The method of claim 3, wherein, ​ ​ 5. A display device, characterized by comprising: ​ ​

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