Patent Description:
A fingerprint module is one of core components of an electronic device. With the continuous development of the electronic device industry, people have growing performance requirements for the fingerprint module, which brings greater challenges to structural design of the fingerprint module.

The structure of the fingerprint module is relatively diverse, and an optical fingerprint module that can be disposed under a display screen may improve the appearance of the electronic device. Therefore, this fingerprint module is used more and more widely. There is a fingerprint recognition region on the display screen, and when a user places a finger on the fingerprint recognition region, the fingerprint module under the fingerprint recognition region may recognize fingerprint information of the user.

<CIT> discloses a display panel, which comprises a first substrate, a second substrate and a liquid crystal layer filled between the first substrate and the second substrate. The second substrate comprises a pixel layer provided with a plurality of pixel units. At least one fingerprint identification unit is arranged in the second substrate and located at a gap of the pixel units.

<CIT> discloses a fingerprint-sensing display capable of sensing a fingerprint on a display screen. The display apparatus having an image scanning function includes an optical amplification cover, one side of which forms a display surface, including a transparent optical amplification layer configured to amplify an optical pattern generated by a fingerprint of a user in contact with the display surface and a cover window for reinforcement, a thin film transistor (TFT) array configured to drive a plurality of pixels forming an image, and an optical sensor array disposed between the optical amplification cover and the TFT array and configured to sense the optical pattern amplified by the optical amplification cover.

<CIT> discloses an optical image acquisition unit, an optical image acquisition system and electronic equipment. The optical image acquisition unit comprises components of an optical focusing device; a diaphragm which is arranged on the back focal plane of the optical focusing device, wherein the diaphragm is provided with a window; a photoelectric sensing unit which is arranged below the diaphragm, wherein the optical focusing device is used for focusing an optical signal in a specific incidence angle range to the window, and the optical signal is transmitted from the window to the photoelectric sensing unit.

The foregoing fingerprint module is usually disposed in a part of the electronic device, so the fingerprint recognition region of the display screen is relatively small, and the user needs to place the finger in a designated fingerprint recognition region for fingerprint recognition, which results in low fingerprint recognition efficiency.

The present disclosure provides a display module and an electronic device to solve the problem of low fingerprint recognition efficiency. To solve the foregoing problem, the following technical solutions are used in the present disclosure:.

A display module, including a first substrate, a surface of one side of the first substrate being provided with an image sensor, a color filter layer, and a black matrix, a surface of the other side of the first substrate being provided with a collimator, the color filter layer and the black matrix being disposed in a same layer, the image sensor being located between the black matrix and the first substrate, and the collimator and the image sensor being arranged at intervals along a direction perpendicular to the first substrate, wherein the other side of the first substrate facing away from the image sensor is provided with a first polarizer, a surface of one side of the first polarizer facing the first substrate is provided with a concave portion, and the collimator is located in the concave portion.

An electronic device, including the foregoing display module.

The technical solutions used in the present disclosure can achieve the following beneficial effects:
In the display module provided in the present disclosure, both the collimator and the image sensor are disposed on the first substrate. The image sensor is corresponding to the black matrix, and the black matrix has a relatively large area in the display module. Therefore, the collimator and the image sensor may be distributed on the display module in a large area, so that an area of the fingerprint recognition region on the display module is enlarged, and the user may freely choose a position to place the finger, thereby improving the fingerprint recognition efficiency.

The accompanying drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of the present disclosure. The illustrative embodiments of the present disclosure and descriptions thereof are used to explain the present disclosure, and do not constitute any improper limitation on the present disclosure. In the accompanying drawings:.

<NUM>-second substrate, <NUM>-first substrate, <NUM>-color filter layer, <NUM>-black matrix, <NUM>-collimator, <NUM>-image sensor, <NUM>-photodiode, <NUM>-first thin film transistor, <NUM>-transparent cover plate, <NUM>-second polarizer, <NUM>-first polarizer, <NUM>-second thin film transistor, <NUM>-liquid crystal layer, <NUM>-frame sealant, <NUM>-backlight module, <NUM>-finger, <NUM>-fingerprint valley, and <NUM>-fingerprint ridge.

To make the objectives, technical solutions, and advantages of the present disclosure clearer, the following clearly and completely describes the technical solutions of the present disclosure with reference to specific embodiments of the present disclosure and the accompanying drawings. Apparently, the described embodiments are merely some rather than all of the embodiments of the present disclosure.

The following describes in detail the technical solutions disclosed in the embodiments of the present disclosure with reference to the accompanying drawings.

As shown in <FIG>, the embodiments of the present disclosure disclose a display module, and the display module may be applied to an electronic device. The display module includes a first substrate <NUM> and may include a second substrate <NUM>, and the second substrate <NUM> and the first substrate <NUM> may be stacked. A surface of one side of the first substrate <NUM> facing the second substrate <NUM> is provided with an image sensor <NUM>, a color filter layer <NUM>, and a black matrix <NUM>. The color filter layer <NUM> and the black matrix <NUM> are disposed in a same layer. Optionally, the color filter layer <NUM> may include a plurality of red filter layers, yellow filter layers, and blue filter layers, and all of these filter layers may be arranged in an array. The black matrix <NUM> may fill gaps between adjacent groups of the red filter layer, the yellow filter layer, and the blue filter layer, thereby shielding a wiring structure. Therefore, a distribution area of the black matrix <NUM> in the display module is relatively large, basically corresponding to an entire display region of the display module.

The image sensor <NUM> is corresponding to the black matrix <NUM>, and the image sensor <NUM> is located between the black matrix <NUM> and the first substrate <NUM>. A surface of one side of the first substrate <NUM> facing away from the second substrate <NUM> is provided with a collimator <NUM>, and the collimator <NUM> and the image sensor <NUM> are arranged at intervals along a direction perpendicular to the first substrate <NUM>. The collimator <NUM> and the image sensor <NUM> herein may be used together for fingerprint recognition. Optionally, the collimator <NUM> is provided with a plurality of light transmission holes, and axes of these light transmission holes may be perpendicular to the image sensor <NUM>. The collimator <NUM> may control a luminous flux passing through the collimator <NUM> according to the principle of pin-hole imaging. The image sensor <NUM> may sense light, and may convert a light signal into an electrical signal.

In addition, the display module further includes a transparent cover plate <NUM>, a first polarizer <NUM>, and a second polarizer <NUM>. The second polarizer <NUM> is disposed on a side of the second substrate <NUM> facing away from the first substrate <NUM>, the first polarizer <NUM> is disposed on a side of the first substrate <NUM> facing away from the second substrate <NUM>, and the transparent cover plate <NUM> is disposed on a side of the first polarizer <NUM> facing away from the first substrate <NUM>.

When the user places a finger <NUM> on the transparent cover plate <NUM>, a light in the display module is reflected by a fingerprint of the user (for details, refer to an optical path indicated by a dashed line with arrow in <FIG>). A fingerprint valley <NUM> and a fingerprint ridge <NUM> of the finger <NUM> of the user have different reflection effects on light, and therefore, the light reflected by the finger <NUM> carries fingerprint information of the user. The reflected light irradiates the image sensor <NUM> through the light transmission holes of the collimator <NUM>, and the image sensor <NUM> senses a light signal, and then converts the light signal representing the fingerprint information into an electrical signal. The electrical signal may be transmitted to a main board of the electronic device, and the main board may be used to judge whether the obtained fingerprint information is consistent with pre-stored fingerprint information, thereby judging whether an access operation of the user is valid.

In the display module disclosed in the embodiments of the present disclosure, both the collimator <NUM> and the image sensor <NUM> are disposed on the first substrate <NUM>, the collimator <NUM> and the image sensor <NUM> are arranged at intervals along the direction perpendicular to the first substrate <NUM>, and the image sensor <NUM> is corresponding to the black matrix <NUM>. The black matrix <NUM> has a relatively large area in the display module, and therefore, the collimator <NUM> and the image sensor <NUM> may be distributed on the display module in a large area, so that an area of the fingerprint recognition region on the display module is enlarged, and the user may freely choose a position to place the finger <NUM>, thereby improving the fingerprint recognition efficiency. In addition, a process of disposing the collimator <NUM> and the image sensor <NUM> on the first substrate <NUM> is relatively simple. Therefore, when the collimator <NUM> and the image sensor <NUM> are disposed in a large area, costs of the display module may not be too high.

Specifically, the collimator <NUM> is located between the first substrate <NUM> and the first polarizer <NUM>. However, since the collimator <NUM> has a specific thickness, a thickness of the entire display module may be increased when the collimator <NUM> is disposed in this way, resulting in the increase of the thickness of the display module. Therefore, a surface of one side of the first polarizer <NUM> facing the first substrate <NUM> is provided with a concave portion, and the collimator <NUM> is located in the concave portion. At this time, the collimator <NUM> may make full use of a space occupied by the first polarizer <NUM>, but basically does not occupy additional space, thereby reducing the thickness of the display module. Optionally, the concave portion herein may be formed by processes such as exposure.

Since the image sensor <NUM> is relatively thin, in order to simplify a molding process of the image sensor <NUM>, the image sensor <NUM> is disposed on a surface of one side of the first substrate <NUM> facing away from the collimator <NUM>. For example, the image sensor <NUM> may be formed on a surface of the first substrate <NUM> by coating or the like.

As described above, the black matrix <NUM> is distributed in a large area in the display module, so corresponding to the black matrix <NUM>, the collimator <NUM> and the image sensor <NUM> may also be distributed in a large area, thereby further expanding the fingerprint recognition region. That is, the display module has a fingerprint recognition region, both the collimator <NUM> and the image sensor <NUM> are located in the fingerprint recognition region, and the fingerprint recognition region extends to an edge of the first substrate <NUM>, so that a region covered by the collimator <NUM> and the image sensor <NUM> is substantially the same size as a region where the first substrate <NUM> is located, thereby realizing full-screen unlocking.

In an optional embodiment, in the direction perpendicular to the first substrate <NUM>, a center of a projection of the collimator <NUM> overlaps with a center of a projection of the image sensor <NUM>. The collimator <NUM> and the image sensor <NUM> may have a same shape, and when the centers of the projections thereof overlap, relative positions thereof are more accurate, which makes arrangement of the collimator <NUM> and the image sensor <NUM> easier, thereby improving accuracy of fingerprint recognition.

There may be one collimator <NUM> and one image sensor <NUM>, but this structure has higher requirements on the molding process, and an area of a single collimator <NUM> or an image sensor <NUM> is too large, utilization of some regions is low, which may lead to high costs of the display module. In view of this, a plurality of collimators <NUM> and a plurality of image sensors <NUM> may be disposed, the plurality of collimators <NUM> and the plurality of image sensors <NUM> are all disposed at intervals, and the plurality of collimators <NUM> and the plurality of image sensors <NUM> are arranged in one-to-one correspondence, so that the collimator <NUM> and the image sensor <NUM> are easier to form, and areas thereof are appropriately reduced, thereby reducing the costs of the display module. Certainly, the relative positions of the corresponding collimator <NUM> and the image sensor <NUM> are easier to be ensured in this structure, thereby improving the accuracy of fingerprint recognition.

Specifically, a single image sensor <NUM> may include only one optical-to-electrical conversion unit. In another embodiment, the image sensor <NUM> may include a plurality of optical-to-electrical conversion units connected in series. As shown in <FIG>, the optical-to-electrical conversion unit includes a photodiode <NUM> and a first thin film transistor <NUM>, and the photodiode <NUM> is electrically connected to the first thin film transistor <NUM>. Specifically, the first thin film transistor <NUM> has a source (namely, an S pole in the figure), a drain (namely, a D pole in the figure), and a gate (namely, a G pole in the figure), the photodiode <NUM> is electrically connected to the source, the drain may be electrically connected to a data line, and the gate may be electrically connected to a gate line. The light reflected by the fingerprint may be projected onto the photodiode <NUM>, causing a resistance value of the photodiode <NUM> to change, resulting in a leakage current signal. The photodiode <NUM> transmits the leakage current signal to a corresponding signal receiving unit through the first thin film transistor <NUM> in a conducting state, so as to recognize the fingerprint information.

In a further embodiment, a surface of one side of the second substrate <NUM> facing the first substrate <NUM> is provided with a second thin film transistor <NUM>, a liquid crystal layer <NUM> is disposed between the second substrate <NUM> and the first substrate <NUM>, and an edge of the liquid crystal layer <NUM> is provided with frame sealant <NUM>. In other words, the display module may be a liquid crystal display module, so as to achieve the purpose of setting a fingerprint recognition structure under the screen in the liquid crystal display module. Certainly, the structure disclosed in the embodiments of the present disclosure may also be applied to an OLED (Organic Light-Emitting Diode) display module, an AMOLED (Active-matrix organic light-emitting diode) display modules, and other types of display modules.

The embodiments of the present disclosure further disclose an electronic device, including the display module described in any one of the foregoing embodiments. Optionally, when the display module is a liquid crystal display module, the electronic device may further include a backlight module <NUM>, and the backlight module <NUM> may be disposed on a side of the second polarizer <NUM> facing away from the second substrate <NUM>. The backlight module <NUM> may emit light to provide a light source for the display module. Since the collimator <NUM> and the image sensor <NUM> are disposed above the backlight module <NUM>, the backlight module <NUM> may not affect a normal operation of the collimator <NUM> and the image sensor <NUM>.

The electronic device disclosed in the embodiments of the present disclosure may be a smartphone, a tablet computer, an e-book reader, or a wearable device. Certainly, the electronic device may also be another device, which is not limited in this embodiment of the present disclosure.

The foregoing embodiments of the present disclosure focus on describing differences between the embodiments, and different optimization features of the embodiments may be combined to form better embodiments provided that they are not contradictory and that they are within the scope of the claims. Considering brevity, details are not described herein again.

Claim 1:
A display module, comprising a first substrate (<NUM>), a surface of one side of the first substrate (<NUM>) being provided with an image sensor (<NUM>), a color filter layer (<NUM>), and a black matrix (<NUM>), a surface of the other side of the first substrate (<NUM>) being provided with a collimator (<NUM>), the color filter layer (<NUM>) and the black matrix (<NUM>) being disposed in a same layer, the image sensor (<NUM>) being located between the black matrix (<NUM>) and the first substrate (<NUM>), and the collimator (<NUM>) and the image sensor (<NUM>) being arranged at intervals along a direction perpendicular to the first substrate (<NUM>); wherein the other side of the first substrate (<NUM>) facing away from the image sensor (<NUM>) is provided with a first polarizer (<NUM>), characterised in that a surface of one side of the first polarizer (<NUM>) facing the first substrate (<NUM>) is provided with a concave portion, and the collimator (<NUM>) is located in the concave portion.