Array substrate and detection method thereof and display device

[0037] In view of the problem in the prior art that the strong light reflection performance of the metal light shielding layer affects the display effect of the display panel, embodiments of the present invention provide an array substrate, a detection method thereof, and a display device.

[0038] In the following, specific implementations of the array substrate, the detection method thereof, and the display device provided by the embodiments of the present invention will be described in detail with reference to the accompanying drawings. The thickness and shape of each film layer in the drawings do not reflect the true ratio, and the purpose is only to illustrate the content of the present invention schematically.

[0039] The embodiment of the present invention provides an array substrate, such as figure 1 As shown, it includes: a base substrate 10, thin film transistors 11 on the base substrate 10, for example, a plurality of thin film transistors arranged in an array, and a photosensitive layer 12 on the base substrate 10; wherein,

[0040] The photosensitive layer 12 includes: a light shielding portion 121;

[0041] The orthographic projection of the pattern of the shading portion 121 on the base substrate 10 at least partially shields the pattern of the active layer 111 of the thin film transistor 11, and the shading portion 121 is located on the side of the active layer 111 of the thin film transistor 11 away from the gate 112;

[0042] The array substrate provided by the embodiment of the present invention uses the light-shielding portion in the photosensitive layer to block the pattern of the active layer. Since the photosensitive layer is irradiated by light, a photo-generated current is generated, that is, the photosensitive layer can convert light energy into electric energy. Therefore, the photosensitive layer has With a certain light absorption effect, most of the light is absorbed by the photosensitive layer, thereby reducing the light reflection performance of the light shielding part, and will not affect the display effect of the display device.

[0043] Further, the orthographic projection of the pattern of the light shielding portion 121 on the base substrate 10 completely shields the pattern of the active layer 111 of the thin film transistor 11.

[0044] Further, in the above-mentioned array substrate provided by the embodiment of the present invention, reference is also made to figure 1 , The above-mentioned photosensitive layer 12 may also include:

[0045] The fingerprint recognition part 122 formed by the same patterning process as the shading part 121;

[0046] The fingerprint recognition unit 122 is electrically connected to the input terminal 113 of the thin film transistor 11.

[0047] The fingerprint recognition portion 122 and the light shielding portion 121 are manufactured through a single patterning process, that is, the light shielding portion 121 and the fingerprint recognition portion 122 are of the same layer and the same material, which saves a patterning process, thereby simplifies the manufacturing process of the array substrate and saves costs.

[0048] In specific implementation, the fingerprint recognition unit 122 can not only recognize fingerprints, but also can be multiplexed as touch electrodes to realize touch detection. That is, the fingerprint recognition unit 122 can realize touch detection and fingerprint recognition respectively through time-sharing driving. .

[0049] In specific implementation, the photosensitive layer 12 is generally made of a photosensitive semiconductor. The photosensitive layer 12 will generate photocurrent when irradiated by light, that is, the photosensitive layer 12 can convert light energy into electrical energy. Therefore, the photosensitive layer 12 has a certain light absorption effect. Therefore, the light absorption characteristics of the photosensitive layer 12 can be used as a light shielding layer. In addition, the difference in the light intensity reflected by the valleys and ridges of the finger can be used to make the photocurrent of the photosensitive layer 12 different to determine the positions of the valleys and ridges of the finger. That is, the photosensitive layer 12 is used to realize the function of fingerprint recognition. Therefore, the light shielding part 121 and the fingerprint recognition part 122 can be set to the same layer and the same material. In this way, the light shielding layer and the fingerprint recognition part 122 can be formed through a single patterning process, without the need for separate light shielding Section 121 saves a patterning process.

[0050] Optionally, in order to avoid the influence of the photocurrent in the light shielding portion 121 on fingerprint recognition, there is no electrical signal connection between the light shielding portion 121 and the fingerprint recognition portion 122.

[0051] It should be noted that in the embodiment of the present invention, the input terminal 113 of the thin film transistor 11 may be a source or a drain, that is, when the input terminal 113 is a source, the output terminal 114 is a drain; or the input terminal 113 is When it is the drain, the output terminal 114 is the source. The fingerprint recognition unit 122 is electrically connected to the input terminal 113 of the thin film transistor 11, so that fingerprint recognition and detection can be realized by reading the current of the output terminal 114 of the thin film transistor 11.

[0052] Reference figure 1 , figure 1 Taking the bottom-gate type of the thin film transistor 11 on the array substrate as an example for illustration, the pattern of the light shielding portion 121 is set to the pattern of the orthographic projection on the base substrate 10 to shield the active layer 111 of the thin film transistor 11, and the light shielding portion 121 is located on the side of the active layer 111 of the thin film transistor 11 away from the gate 112, so that the channel region of the thin film transistor 11 can be effectively shielded to prevent external light from affecting the switching characteristics of the thin film transistor 11. It should be noted that the array substrate provided by the embodiment of the present invention is also applicable to the top-gate thin film transistor 11. The gate 112 of the top-gate thin film transistor 11 is located on the side of the active layer 111 away from the base substrate 10, and the light shielding portion 121 It is also arranged on the side of the active layer 111 away from the gate 112. For the top-gate thin film transistor 11, the light-shielding portion 121 can block the light of the backlight source to prevent the light from the backlight source from irradiating the active layer 111 to the thin film transistor 11 The switching characteristics of the For ease of production, for the top-gate thin film transistor 11, the fingerprint identification part 122 can be arranged on the side of the input terminal 113 of the thin film transistor 11 close to the base substrate 10, and the conduction part related to the fingerprint identification part 122 can also be made corresponding Adjustment. For ease of illustration, the drawings in the embodiments of the present invention all use bottom-gate thin film transistors 11 for illustration. In specific implementation, all the embodiments in the embodiments of the present invention can be applied to top-gate thin film transistors 11.

[0053] Furthermore, in the above-mentioned array substrate provided by the embodiment of the present invention, such as image 3 As shown, the pattern of the above-mentioned light shielding portion 121 can also be multiplexed as touch electrodes;

[0054] The aforementioned array substrate may further include: a touch detection signal line 19 provided on the same layer as the gate 112 of the thin film transistor 11;

[0055] The touch detection signal line 19 is electrically signal connected to the corresponding light shielding portion 121.

[0056] In the above, according to the arrangement of the thin film transistors on the array substrate, a plurality of touch detection signal lines can be provided accordingly. By arranging the touch detection signal line 19 in the same layer as the gate 112, on the one hand, the touch detection signal line 19 and the gate 112 can be made by the same patterning process, saving one patterning process; on the other hand, it can be read The current of each touch detection signal line 19 determines the touch position. If the current of the touch detection signal line 19 at a certain position changes, the position where the corresponding light shielding portion 121 is located is touched. Therefore, image 3 In the structure of the array substrate shown, the fingerprint recognition part 122 realizes the fingerprint recognition function, and the light shielding layer realizes the touch detection function. Fingerprint recognition and touch detection can be independent of each other, and there is no need to multiplex the fingerprint recognition part 122 as touch electrodes. In this way, the drive timing can be simplified.

[0057] The touch detection signal line 19 is used to connect the corresponding light shielding portion 121 with electrical signals to realize the principle of touch display: when the position of the light shielding portion 121 is touched, the light intensity reflected by the finger will change the light of the light shielding portion 121 Therefore, the touch detection signal line 19 can monitor the current change to determine the touch position.

[0058] In practical applications, in the above-mentioned array substrate provided by the embodiment of the present invention, the touch detection signal line 19 corresponds to the light shielding portion 121 one-to-one, or,

[0059] Each touch detection signal line 19 corresponds to a plurality of light shielding parts 121.

[0060] Since the finger and the touch screen have a certain contact area when the finger touches the display screen, the contact area generally corresponds to multiple pixels, so it is possible to set several pixels within a certain range to share the same touch detection signal line 19 to meet the detection accuracy Therefore, the number of touch detection signal lines 19 can be reduced on the premise of meeting the detection accuracy. For example, the light shielding portion 121 of each pixel within a range of 5×5 mm can be connected to the same touch detection signal line 19. When the required detection accuracy is high, the touch detection signal line 19 can also be set to correspond to the light shielding portion 121 one-to-one.

[0061] In practical applications, in the above-mentioned array substrate provided by the embodiments of the present invention, refer to figure 1 , It may further include: a first reference signal line 13 provided in the same layer as the gate 112 of the thin film transistor 11;

[0062] The first reference signal line 13 is electrically signal connected to the corresponding fingerprint identification unit 122.

[0063] In the above, according to the arrangement of the thin film transistors on the array substrate, a plurality of first reference signal lines can be provided accordingly. Since the photosensitive layer 12 is generally made of photosensitive semiconductor, the PN junction or PIN junction formed by the photosensitive semiconductor has unidirectional conductivity. Therefore, in the process of detecting fingerprints, it is necessary to apply a reverse voltage to the fingerprint recognition part 122 to make the fingerprint recognition part The PN junction or PIN junction in 122 is in a reverse biased state. When there is no light, there is a small reverse current in the fingerprint identification part 122. When the fingerprint identification part 122 is illuminated by light, the PN junction or The PIN junction generates electron-hole pairs, which increases the density of minority carriers. These carriers drift under the reverse voltage, which greatly increases the reverse current and forms a photocurrent. The size of the photocurrent is determined by the intensity of light. .

[0064] When P of the fingerprint recognition part 122 is extremely low and N is extremely high, the fingerprint recognition part 122 is in a reverse biased state, because the fingerprint recognition part 122 is electrically connected to the input terminal 113 of the thin film transistor 11 and is connected to the corresponding first reference The signal line 13 is electrically connected. Therefore, different voltages can be applied to the input terminal 113 of the thin film transistor 11 and the first reference signal line 13, so that the fingerprint recognition part 122 is in a reverse biased state, so that the fingerprint recognition part 122 and the thin film transistor The end connected to the input terminal 113 of 11 is the N pole, and the end connected to the first reference signal line 13 is the P pole. For example, a voltage of -1V can be applied to the first reference signal line 13 and the input terminal 113 of the thin film transistor 11 The voltage of +3V is just an example here and does not limit the magnitude of the applied voltage.

[0065] In addition, by arranging the first reference signal line 13 and the gate 112 of the thin film transistor 11 in the same layer, the pattern of the first reference signal line 13 and the gate 112 can be formed by one patterning process in the manufacturing process, avoiding the first Refer to the pattern of the signal line 13 and the gate 112 to save a patterning process.

[0066] The following combination Figure 2a with Figure 2b The principle of fingerprint identification in the embodiment of the present invention is explained:

[0067] Reference Figure 2a with Figure 2b , The gate 112 of each thin film transistor 11 is connected to the gate drive module 22 through the gate line 21, and the output end 114 of each thin film transistor 11 is connected to the data signal receiving module through the data line 23. When fingerprints are detected, the gate drive module 22. The gate 112 is controlled to turn on the thin film transistor 11 row by row. The data signal processing module 24 first inputs a certain voltage to the fingerprint recognition unit 122 to make the fingerprint recognition unit 122 in a reverse bias state, and detects the current magnitude of each data line 23. When the finger is touched, due to the inconsistency of the light intensity reflected by the valley and ridge of the finger, the current magnitude of the data line 23 at the corresponding position is not consistent. The data signal processing module 24 can identify the valley and ridge of the finger according to the magnitude of the current on the data line 23 Position, and then form the fingerprint image of the finger.

[0068] Figure 2a Only four gate lines 21 and four data lines 23 are shown in the figure. The ellipsis in the figure indicates that more gate lines 21 and more data lines 23 are included. The number is limited, Figure 2b Medium V d Indicates the input voltage of the first reference signal line 13.

[0069] In specific implementation, the above-mentioned array substrate provided by the embodiment of the present invention may further include: a second reference signal line provided in the same layer as the gate electrode 112 of the thin film transistor 11;

[0070] The second reference signal line is electrically signal connected to the corresponding light shielding portion 121.

[0071] In the above, according to the arrangement of the thin film transistors on the array substrate, a plurality of second reference signal lines can be correspondingly provided. Since the shading part 121 is used to realize touch detection, the touch position can be determined only by detecting a change in the current at a certain position. Therefore, during the detection process, the shading part 121 can be in a forward biased state or in a reverse state. In the polarized state, by providing a second reference signal line connected to the corresponding light shielding portion 121 with electrical signals, a certain voltage can be applied to the light shielding portion 121 through the second reference signal line and the touch detection signal line 19 so that the light shielding portion 121 is in a positive state. Polarized state or reverse-polarized state. In addition, voltage may not be applied to the shading part 121. The light reflected when a finger touches the shading part 121 will cause the shading part 121 to form a photocurrent. The current of the shading part 121 is directly read through the touch detection signal line 19 , The touch position can also be detected. This detection method is relatively simple. Applying a voltage to the shading part 121 makes the shading part 121 in a forward or reverse biased state, which will make the detected current change more obvious and make it easier to detect the touch. 控位。 Control position.

[0072] The second reference signal line is set to the same layer as the gate electrode 112, and the patterns of the gate electrode 112 and the second reference signal line can be formed through the same patterning process, which saves one patterning process and saves cost.

[0073] In specific implementation, the above-mentioned first reference signal line 13 and the second reference signal line may be the same reference signal line.

[0074] The first reference signal line 13 and the second reference signal line are the same signal line. Taking the first reference signal line 13 as an example for description, a certain voltage can be applied to the first reference signal line 13 during the detection process. In order to keep the position of the first reference signal line 13 at a certain potential, a certain voltage can be applied to the input terminal 113 of the thin film transistor 11 to keep the fingerprint recognition unit 122 in a reverse bias state and apply to the touch detection signal line 19. A certain voltage keeps the light shielding part 121 in a forward or reverse bias state. For example, a voltage of -2V can be applied to the first reference signal line 13, and a voltage of +1V can be applied to the input terminal 113 of the thin film transistor 11. Applying +2 to the detection signal line 19 makes the light shielding part 121 in a reverse biased state, or applying a voltage of -5V to the touch detection signal line 19 makes the light shielding part 121 in a forward biased state, so that the touch detection and fingerprint recognition detection can be shared Reference signal line, and does not affect the test results.

[0075] In specific implementation, the above-mentioned array substrate provided by the embodiment of the present invention, such as image 3 As shown, it may further include: a gate insulating layer 14 located between the active layer 111 and the gate 112 of the thin film transistor 11, and a first insulating layer 15 located between the active layer 111 and the photosensitive layer 12 of the thin film transistor 11 , And the second insulating layer 16 on the side of the photosensitive layer 12 away from the gate 112 of the thin film transistor 11.

[0076] The gate insulating layer 14 may function to isolate the active layer 111 and the gate 112, the first insulating layer 15 may function to isolate the active layer 111 from the light shielding portion 121, and the second insulating layer 16 may function To the effect of flattening.

[0077] In practical applications, in order to realize the electrical signal connection between the fingerprint recognition portion 122 and the corresponding first reference signal line 13 and the electrical signal connection between the light shielding portion 121 and the corresponding touch detection signal line 19, refer to image 3 , The above-mentioned array substrate provided by the embodiment of the present invention may further include: a first conductive portion 131 and a second conductive portion 132 disposed on the same layer as the input terminal 113 of the thin film transistor 11, and located on the second insulating layer 16 away from the liner The third conductive portion 191 and the fourth conductive portion 192 provided in the same layer on the side of the base substrate 10;

[0078] The first reference signal line 13 is electrically signal connected to the fingerprint identification portion 122 through the first conductive portion 131 and the third conductive portion 191;

[0079] The touch detection signal line 19 is electrically signal connected to the light shielding portion 121 through the second conductive portion 132 and the fourth conductive portion 192.

[0080] Same reference image 3 , The first conductive portion 131 and the second conductive portion 132 are arranged in the same layer as the input terminal 113 of the thin film transistor 11. Therefore, the input terminal 113, the first conductive portion 131 and the second conductive portion 131 of the thin film transistor 11 can be formed by one patterning process. For the pattern of the conductive portion 132, in order to connect the first conductive portion 131 to the first reference signal line 13, before the pattern of the first conductive portion 131 is formed, the gate insulating layer 14 corresponds to the first reference The via hole is made at the position of the signal line 13, which can be specifically realized by an etching process. Similarly, in order to electrically connect the second conductive portion 132 with the touch detection signal line 19, it is necessary to form the second conductive portion 132 Before the patterning, a via hole is formed at the position of the gate insulating layer 14 corresponding to the touch detection signal line 19, which can be specifically formed with the via hole at the corresponding position of the first reference signal line 13 by using the same etching process.

[0081] The third conducting portion 191 and the fourth conducting portion 192 are arranged in the same layer, so the patterns of the third conducting portion 191 and the fourth conducting portion 192 can be formed by one patterning process. Because the fingerprint recognition portion 122 uses the valley of a finger Different from the light intensity of the ridge reflection to realize fingerprint recognition, the light shielding part 121 also generates photocurrent to detect the touch position by the light reflected by the finger. Therefore, in order to prevent the third conducting part 191 from blocking the fingerprint recognition part 122, and To prevent the fourth conductive portion 192 from blocking the light shielding portion 121, the third conductive portion 191 and the fourth conductive portion 192 are preferably made of a transparent conductive material, for example, indium tin oxide (ITO) or the like.

[0082] Such as image 3 As shown, in order to realize the electrical signal connection between the fingerprint recognition portion 122 and the first conductive portion 131, and further realize the electrical signal connection between the fingerprint recognition portion 122 and the first reference signal line 13, a third conductive portion is formed. Before the pattern of 191, via holes need to be formed at the positions of the first insulating layer 15 and the second insulating layer 16 corresponding to the first conductive portion 131. In the same way, in order to realize the electrical signal connection between the light shielding portion 121 and the second conductive portion 132, and further realize the electrical signal connection between the light shielding portion 121 and the touch detection signal line 19, the fourth conductive portion 192 is formed Before patterning, it is necessary to form via holes at the positions of the first insulating layer 15 and the second insulating layer 16 corresponding to the second conductive portion 132. During the manufacturing process, the first insulating layer 15 and the second insulating layer 16 correspond to the The vias of the first conductive portion 131 and the second conductive portion 132 can be fabricated together using the same etching process.

[0083] In addition, on the side of the third conductive portion 191 and the fourth conductive portion 192 facing away from the base substrate 10, a third insulating layer 17 is also provided, which can provide a gap between the third conductive portion 191 and the fourth conductive portion 192. Play a protective role, and play a flattening role.

[0084] In the actual process, when making the pattern of the allergy layer and making the via hole in the second insulating layer 16, an etching process is required. In order to avoid the etching liquid used in the etching process from affecting the photosensitive layer 12 Damage to the surface, such as figure 1 with image 3 As shown, the above-mentioned array substrate provided by the embodiment of the present invention may further include: a protective layer 18 on the side of the photosensitive layer 12 away from the base substrate 10;

[0085] The pattern of the protective layer 18 is consistent with the pattern of the photosensitive layer 12.

[0086] In the same consideration as the third conducting portion 191 and the fourth conducting portion 192, in order to prevent the protection layer 18 from affecting the detection accuracy of the fingerprint recognition portion 122 to detect fingerprints, and the detection accuracy of the light shielding portion 121 to detect the touch position, the protection layer 18 Preferably, it is made of a transparent conductive material, for example, indium tin oxide (ITO) and other materials.

[0087] In a specific implementation, the above-mentioned photosensitive layer 12 is preferably composed of a PIN-type semiconductor material, and may be made of amorphous silicon or polycrystalline silicon material. The P pole and N pole of the photosensitive layer 12 can be set according to actual needs. For example, the side close to the base substrate 10 can be set as the N pole, and the side far away from the base substrate 10 can be set as the P pole. This is just an example. , Does not limit the specific implementation of the light shielding layer.

[0088] Based on the same inventive concept, the embodiment of the present invention also provides a detection method of the above-mentioned array substrate. Since the principle of the detection method to solve the problem is similar to the above-mentioned array substrate, the implementation of the detection method can refer to the implementation of the above-mentioned array substrate, and the repetition will not be repeated.

[0089] The embodiment of the present invention provides a method for fingerprint detection based on the above-mentioned array substrate, such as Figure 4 Shown, including:

[0090] S301, inputting a turn-on signal to the gate of the thin film transistor on the array substrate;

[0091] S302: Detect the fingerprint identification signal at the output terminal of the thin film transistor, and determine the fingerprint pattern according to the fingerprint identification signal.

[0092] The detection method of the above-mentioned array substrate provided by the embodiment of the present invention utilizes the different light intensity reflected by the finger valley and the ridge, so that the photocurrent formed in the fingerprint recognition part at the corresponding position is different, by inputting to the gate of the thin film transistor Turn-on signal, for example, input the turn-on signal row by row or column by row, so that the input and output of the thin film transistor are turned on row by row or column by row, and then the fingerprint can be determined by detecting the fingerprint identification signal at the output of each thin film transistor pattern.

[0093] It should be noted that the array substrate in the detection method provided by the embodiment of the present invention refers to an array substrate in which the photosensitive layer includes a light shielding part and a fingerprint recognition part.

[0094] Further, the detection method of the above-mentioned array substrate provided by the embodiment of the present invention can also realize touch detection, which can be specifically realized in the following two ways:

[0095] Implementation mode 1: The above detection method may also include:

[0096] The touch detection signal at the output end of the thin film crystal is detected, and the touch position is determined according to the touch detection signal.

[0097] The fingerprint recognition unit can be multiplexed as a touch electrode. When a finger touches the display screen, the light reflected by the finger will form a photocurrent in the fingerprint recognition unit, so it can be changed according to the current at the output terminal of the thin film transistor connected to the fingerprint recognition unit. To determine the touch position, specifically, touch detection and fingerprint recognition can be realized respectively through time-sharing driving. During the touch detection period, the touch detection signal at the output terminal of each thin film transistor is detected, and the touch detection signal Determine the touch location.

[0098] Implementation method two:

[0099] The aforementioned array substrate may include: touch detection signal lines provided on the same layer as the gate of the thin film transistor;

[0100] Each touch detection signal line is connected with the corresponding electric signal of the shading part;

[0101] The above detection method may also include:

[0102] The touch detection signal of the touch detection signal line is detected, and the touch position is determined according to the touch detection signal.

[0103] By setting each touch detection signal line connected to the corresponding electric signal of the shading part, the touch position can be determined by reading the current of each touch detection signal line. If the current of the touch detection signal line at a certain position changes, Then the position of the corresponding light-shielding part is touched. Therefore, the fingerprint recognition function can be realized through the fingerprint recognition part, and the touch detection function is realized through the light-shielding layer. Fingerprint recognition and touch detection can be independent of each other, and there is no need to duplicate the fingerprint recognition part. Used as a touch electrode, in this way, the driving sequence can be simplified.

[0104] Based on the same inventive concept, an embodiment of the present invention also provides a display panel including the above-mentioned array substrate. The type of the display panel is not particularly limited. For example, it may be an LCD display panel, an OLED display panel, a QLED display panel, a Micro LED display panel, and the like. Since the principle of solving the problem of the display device is similar to the above-mentioned array substrate, the implementation of the display device can refer to the implementation of the above-mentioned array substrate, and the repetition will not be repeated.

[0105] Based on the same inventive concept, the embodiments of the present invention also provide a display device, including the above-mentioned display panel. The display device can be applied to mobile phones, tablet computers, televisions, monitors, notebook computers, digital photo frames, navigators, etc. Functional products or components. Since the principle of solving the problem of the display device is similar to the above-mentioned array substrate, the implementation of the display device can refer to the implementation of the above-mentioned array substrate, and the repetition will not be repeated.

[0106] In the array substrate provided by the embodiment of the present invention, by setting the shading part to be the same layer and the same material as the fingerprint identification part, the fingerprint identification part and the shading part can be manufactured through a single patterning process, and there is no need to make the shading part separately, which saves one composition The manufacturing process of the array substrate is simplified, and the cost is saved. In addition, by setting each touch detection signal line connected to the corresponding electric signal of the shading part, the touch position can be determined by reading the current of each touch detection signal line. If the current of the touch detection signal line at a certain position is If there is a change, the position of the corresponding shading part is touched. Therefore, the fingerprint recognition function can be realized by the fingerprint recognition part, and the touch detection function can be realized by the shading layer. Fingerprint recognition and touch detection can be independent of each other, and there is no need to change the fingerprint The identification part is multiplexed as touch electrodes, so that the driving sequence can be simplified.

[0107] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. In this way, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.