CN110737136B

CN110737136B - Backlight module and display device

Info

Publication number: CN110737136B
Application number: CN201911050477.XA
Authority: CN
Inventors: 黄阿海
Original assignee: Xiamen Tianma Microelectronics Co Ltd
Current assignee: Xiamen Tianma Microelectronics Co Ltd
Priority date: 2019-10-31
Filing date: 2019-10-31
Publication date: 2022-07-12
Anticipated expiration: 2039-10-31
Also published as: CN110737136A

Abstract

The invention discloses a backlight module and a display device, relating to the technical field of display, wherein the backlight module comprises: a fingerprint identification area and a non-fingerprint identification area; the backlight module further comprises a light guide plate, a plurality of grooves are formed in the surface of one side of the light guide plate and located on the light emitting surface of the light guide plate, the grooves comprise a plurality of first grooves located in the non-fingerprint identification area and a plurality of second grooves located in the fingerprint identification area, the first grooves are linear grooves, and the second grooves are curved grooves. The invention solves the problem that the brightness of the fingerprint identification area in the display device in the prior art is lower than that of the non-fingerprint identification area, and improves the brightness uniformity of the display device.

Description

Backlight module and display device

Technical Field

The invention relates to the technical field of display, in particular to a backlight module and a display device.

Background

The fingerprint is an invariant feature unique to human bodies and distinguishable from others, and with the rapid development of display technologies, display panels with fingerprint identification functions have gradually spread throughout the lives of people, and fingerprint identification is widely applied to display screens of electronic devices such as mobile phones, personal digital assistants, computers and the like.

At present, the fingerprint identification technology is combined with the display technology generally, so that the display panel not only has a display function, but also can carry out fingerprint identification, thereby enriching the functions of the display panel and improving the safety performance of information in the display device. Further, combine together optics fingerprint identification technique and display technology, can make the fingerprint identification region be located the display area, overcome the regional setting of fingerprint identification and account for the lower problem of ratio at the display panel's that leads to in non-display area screen, avoided the regional setting of fingerprint identification to be used for experiencing relatively poor problem that leads to when display panel's the back simultaneously.

An important difficulty of applying optical fingerprint identification to a display technology is that a light sensing unit needs to be arranged in a fingerprint identification area in a display panel of a display, so that the penetration rate of the fingerprint identification area in the display panel is inevitably reduced, and further the brightness of the fingerprint identification area is lower than that of a non-fingerprint identification area, and the brightness uniformity of the display device is influenced.

Disclosure of Invention

In view of this, the present invention provides a backlight module and a display device, which solve the problem in the prior art that the luminance of the fingerprint identification area is lower than the luminance of the non-fingerprint identification area, and improve the luminance uniformity of the display device.

In a first aspect, the present invention provides a backlight module, including: a fingerprint identification area and a non-fingerprint identification area; the backlight module further comprises a light guide plate, a plurality of grooves are formed in the surface of one side of the light guide plate and located on the light emitting surface of the light guide plate, the grooves comprise a plurality of first grooves located in the non-fingerprint identification area and a plurality of second grooves located in the fingerprint identification area, the first grooves are linear grooves, and the second grooves are curved grooves.

In a second aspect, the present invention provides a display device comprising: the backlight module comprises a backlight module and a display panel positioned on a light-emitting surface of the backlight module, wherein the backlight module is the backlight module provided by the invention.

Compared with the prior art, the backlight module and the display device provided by the invention at least realize the following beneficial effects:

the backlight module provided by the invention comprises a light guide sheet, wherein the surface of one side of a light-emitting surface in the light guide sheet is provided with a plurality of grooves, the grooves comprise a plurality of first grooves positioned in a non-fingerprint identification area and a plurality of second grooves positioned in a fingerprint identification area, the first grooves are linear grooves, the second grooves are curved grooves, the length of the curved grooves is greater than that of the linear grooves in the same range, and the light condensation effect of the curved grooves is better, therefore, the plurality of second grooves positioned in the fingerprint identification area are set to be the curved grooves, the quantity of light which is injected into a display panel through the fingerprint identification area in a unit area in the backlight module is increased and is greater than that of the light which is injected into the display panel through the non-fingerprint identification area, and the increased quantity of the part of light can compensate the quantity of the part of light which is shielded by a fingerprint sensor, so that the light-emitting brightness of the display device in the fingerprint identification area and the non-fingerprint identification area tends to be the same, the brightness uniformity of the display device is improved.

Of course, it is not necessary for any product in which the present invention is practiced to specifically achieve all of the above-described technical effects simultaneously.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

FIG. 1 is a schematic plan view of a backlight module according to the present invention;

FIG. 2 is a cross-sectional view of the backlight module of FIG. 1 taken along line A-A';

FIG. 3 is a schematic plan view of another backlight module according to the present invention;

FIG. 4 is a schematic plan view of another backlight module according to the present invention;

FIG. 5 is a cross-sectional view of the backlight module shown in FIG. 3 along line B-B';

FIG. 6 is another cross-sectional view taken along line B-B' of the backlight module shown in FIG. 3;

FIG. 7 is a cross-sectional view of the backlight module shown in FIG. 3 taken along line B-B';

FIG. 8 is a cross-sectional view of the backlight module shown in FIG. 3 taken along line B-B';

FIG. 9 is a schematic plan view of another backlight module according to the present invention;

FIG. 10 is a schematic structural diagram of a backlight module according to the present invention;

FIG. 11 is a schematic plan view of a light guide plate in the backlight module shown in FIG. 10;

FIG. 12 is a schematic structural diagram of a display device according to the present invention;

fig. 13 is a cross-sectional view of the display device of fig. 12 taken along C-C'.

Detailed Description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be discussed further in subsequent figures.

It should be noted that although the terms first and second may be used to describe the trenches in the embodiments of the present invention, the trenches should not be limited to these terms. These terms are only used to distinguish the trenches from each other. For example, a first trench may also be referred to as a second trench, and similarly, a second trench may also be referred to as a first trench, without departing from the scope of embodiments of the present invention.

Fig. 1 is a schematic plan view of a backlight module according to the present invention, fig. 2 is a cross-sectional view of the backlight module along a-a' of fig. 1, and referring to fig. 1 and fig. 2, the present embodiment provides a backlight module, including: a fingerprint identification area AA1 and a non-fingerprint identification area AA 2;

the backlight module further comprises a light guide plate 10, a plurality of grooves 11 are formed in the surface of one side of the light guide plate 10, the grooves 11 are located on a light emitting surface of the light guide plate 10, the grooves 11 comprise a plurality of first grooves 12 located in the non-fingerprint identification area AA2 and a plurality of second grooves 13 located in the fingerprint identification area AA1, the first grooves 12 are linear grooves, and the second grooves 13 are curved grooves.

First, it should be noted that, for the display device with the fingerprint identification function, the display device has a fingerprint identification area and a non-fingerprint identification area, in the embodiment of the present invention, the fingerprint identification area AA1 of the backlight module corresponds to the fingerprint identification area of the display device, and the non-fingerprint identification area AA2 of the backlight module corresponds to the non-fingerprint identification area of the display device.

Specifically, with continuing reference to fig. 1 and fig. 2, the backlight module provided in this embodiment includes a light guide plate 10, a plurality of grooves 11 are disposed on a surface of one side of the light exit surface of the light guide plate 10, and light transmitted inside the light guide plate 10 is refracted and reflected by the grooves 11, so as to change a transmission direction thereof, and the light is uniformly dispersed and emitted from the light exit surface of the light guide plate 10.

Since the light transmitted inside the light guide plate 10 is refracted and reflected in the grooves 11, so that the grooves 11 have a light condensing effect, the grooves 11 include a plurality of first grooves 12 located in the non-fingerprint identification area AA2 and a plurality of second grooves 13 located in the fingerprint identification area AA1, wherein the first grooves 12 are linear grooves, the second grooves 13 are curved grooves, and the length of the curved grooves is greater than that of the linear grooves in the same range, so that the light condensing effect of the curved grooves is better, therefore, the plurality of second grooves 13 located in the fingerprint identification area AA1 are set as curved grooves, so that the number of light entering the display panel through the fingerprint identification area AA1 in the unit area of the backlight module is increased, and is greater than the number of light entering the display panel through the non-fingerprint identification area AA2, and the increased number of the light can compensate the part of light shielded by the fingerprint sensor, therefore, the brightness of the display device in the fingerprint identification area and the brightness of the display device in the non-fingerprint identification area tend to be the same, and the brightness uniformity of the display device is improved.

Fig. 3 is a schematic plan view of another backlight module provided in the present invention, referring to fig. 3, optionally, wherein the second groove 13 is an annular groove.

Specifically, with reference to fig. 3, the plurality of second grooves 13 in the fingerprint identification area AA1 are annular grooves, and since the light transmitted inside the light guide plate 10 is refracted in the grooves 11, the light condensing effect of the annular grooves is better, therefore, the plurality of second grooves 13 in the fingerprint identification area AA1 are annular grooves, the number of light rays incident on the display panel via the fingerprint identification area AA1 in a unit area in the backlight module is further increased, which is greater than the number of light rays incident on the display panel via the non-fingerprint identification area AA2, and the increased number of light rays can compensate the number of light rays blocked by the fingerprint sensor, so that the luminance of the display device in the fingerprint identification area and the non-fingerprint identification area tends to be the same, and the luminance uniformity of the display device is improved.

Because the line of fingerprint is close to being annular structure, a plurality of second slot 13 that are located fingerprint identification district AA1 set up to annular groove, and the shape of second slot 13 and the line of fingerprint are close for the light path that refracts out via second slot 13 matches with the line of fingerprint, effectively alleviates the condition that light takes place to interfere the wadding in disorder when carrying out fingerprint identification, effectively promotes fingerprint identification's efficiency.

Optionally, a vertical projection of the second groove on the light emitting surface of the light guide plate is a circular ring structure or an elliptical ring structure.

Specifically, with reference to fig. 3, the vertical projection of the second groove 13 on the light-emitting surface of the light guide plate 10 is a circular ring structure. Fig. 4 is a schematic plan view of another backlight module according to the present invention, and referring to fig. 4, a vertical projection of the second groove 13 on the light-emitting surface of the light guide plate 10 is an elliptical ring structure. It should be noted that, in the embodiment, the vertical projection of the second groove 13 on the light-emitting surface of the light guide plate 10 is exemplarily shown to be a circular ring structure or an elliptical ring structure, in other embodiments of the present invention, the vertical projection of the second groove on the light-emitting surface of the light guide plate may also be in other shapes, and the description of the present invention is omitted here.

With reference to fig. 3, optionally, the centers of the vertical projections of the second grooves 13 on the light-emitting surface of the light guide plate 10 are located at the same point.

Specifically, with reference to fig. 3, the centers of the second grooves 13 in the vertical projection of the light-emitting surface of the light guide plate 10 are located at the same point, and the second grooves 13 are disposed on the basis of the same point, so that the process difficulty of the light guide plate is reduced, and the production cost is reduced.

With continued reference to fig. 3, optionally, wherein the second trenches 13 are equally spaced apart.

Specifically, with reference to fig. 3, because the light transmitted inside the light guide plate 10 is refracted and reflected in the grooves 11, the grooves 11 have a light condensing effect, the centers of the second grooves 13 located in the fingerprint identification area AA1 and the vertical projection of the light exit surface of the light guide plate 10 are located at the same point, and the second grooves 13 are arranged at equal intervals, so that the number of light incident on the display panel from each part in the fingerprint identification area AA1 in the backlight module is relatively uniform, the light emitting brightness of each part of the display device in the fingerprint identification area tends to be the same, and the brightness uniformity of the display device is improved.

With continued reference to fig. 3, optionally, wherein the light guide plate 10 includes a first edge 14 extending along a first direction X, and a second edge 15 extending along a second direction Y, the first direction X and the second direction Y intersecting;

the first grooves 12 extend along a first direction X, and the first grooves 12 are arranged along a second direction Y.

Specifically, with continued reference to fig. 3, the first grooves 12 of the light guide plate 10 extend along the first direction X, and the first grooves 12 are arranged along the second direction Y, so that the light transmitted inside the light guide plate 10 is refracted and reflected by the first grooves 12, thereby changing the transmission direction thereof, so that the light is uniformly dispersed and emitted from the non-fingerprint identification area AA2 of the light guide plate 10.

It should be noted that, in this embodiment, the first trenches 12 are exemplarily shown to extend along the first direction X, and the first trenches 12 are arranged along the second direction Y, in other embodiments of the present invention, the first trenches may also extend and be arranged along other directions, which is not described herein again.

FIG. 5 is a cross-sectional view of the backlight module shown in FIG. 3 taken along line B-B', referring to FIGS. 3 and 5, wherein, alternatively, the width of the second grooves 13 is 10-30 μm, the depth of the second grooves 13 is 1-10 μm, and the distance between two adjacent second grooves 13 is 10-50 μm;

the groove width of the first grooves 12 is 10-50 μm, the groove depth of the first grooves 12 is 1-10 μm, and the distance between two adjacent first grooves 12 is 10-50 μm.

Specifically, with continued reference to fig. 3 and 5, the width of the second trench 13 is d1, the depth of the second trench 13 is h1, and the distance between two adjacent first trenches 12 is p1, wherein d1 is greater than or equal to 10 μm and less than or equal to 30 μm, h1 is greater than or equal to 1 μm and less than or equal to 10 μm, and p1 is greater than or equal to 10 μm and less than or equal to 50 μm. The light is effectively uniformly scattered from the fingerprint identification area AA1 of the light guide plate 10 without increasing the process difficulty of the second grooves 13. The groove width of the first grooves 12 is d2, the groove depth of the first grooves 12 is h2, and the distance between two adjacent first grooves 12 is p2, wherein d2 is more than or equal to 10 mu m and less than or equal to 50 mu m, h2 is more than or equal to 1 mu m and less than or equal to 10 mu m, and p2 is more than or equal to 10 mu m and less than or equal to 50 mu m. The light is effectively uniformly dispersed and emitted from the non-fingerprint identification area AA2 of the light guide plate 10 without increasing the process difficulty of the first grooves 12.

It should be noted that the present embodiment exemplarily shows that the groove width of the second trench 13 is 10 to 30 μm, the groove depth of the second trench 13 is 1 to 10 μm, and the distance between two adjacent second trenches 13 is 10 to 50 μm; the groove width of the first groove 12 is 10-50 μm, the groove depth of the first groove 12 is 1-10 μm, and the distance between two adjacent first grooves 12 is 10-50 μm, in the actual production engineering of the present invention, the groove width of the second groove 13, the groove depth of the second groove 13, the distance between two adjacent second grooves 13, the groove width of the first groove 12, the groove depth of the first groove 12, and the distance between two adjacent first grooves 12 can be set according to the actual production requirements.

Optionally, the groove includes at least two first groove surfaces, and the first groove surfaces are of a planar structure;

or the groove comprises at least one second groove surface which is of an arc surface structure.

In particular, with continued reference to fig. 3 and 5, the trench 11 includes at least two first trench faces 111, the first trench faces 111 being of planar configuration. Fig. 6 is another cross-sectional view of the backlight module shown in fig. 3 along B-B', and referring to fig. 3 and 6, the groove 11 includes at least one second groove surface 112, and the second groove surface 112 has an arc-shaped surface structure.

It should be noted that fig. 5 exemplarily shows that the grooves 11 each include two first groove surfaces 111, and fig. 6 exemplarily shows that the grooves 11 each include two second groove surfaces 112. In the present invention, the first trench 12 and the second trench 13 may have different structures. Illustratively, fig. 7 is a further cross-sectional view of the backlight module shown in fig. 3 along B-B', and referring to fig. 3 and 7, the groove surface in the first groove 12 is a first groove surface 111 with a planar structure, and the groove surface in the second groove 13 is a second groove surface 112 with an arc-shaped surface structure. In other embodiments of the present invention, the first trench 12 and the second trench 13 may be disposed according to actual production requirements, and the present invention is not described herein again.

Optionally, the groove is a V-shaped groove or a U-shaped groove.

In particular, with continued reference to fig. 3 and 5, the trench 11 is a V-shaped trench. Fig. 8 is a cross-sectional view of the backlight module shown in fig. 3 taken along line B-B', and referring to fig. 3 and 8, the groove 11 is a U-shaped groove. It should be noted that, in the embodiment, the groove is exemplarily shown to be a V-shaped groove or a U-shaped groove, in other embodiments of the present invention, the groove may also be a groove with other shapes, and the description of the present invention is omitted.

Optionally, wherein the non-fingerprint identification region at least partially surrounds the fingerprint identification region.

In particular, with continued reference to FIG. 1, the non-fingerprinting area AA2 partially surrounds the fingerprinting area AA 1. With continued reference to FIG. 3, the non-fingerprint identification area AA2 surrounds the fingerprint identification area AA 1.

Fig. 9 is a schematic plan view of another backlight module provided by the present invention, referring to fig. 9, wherein, alternatively, the non-fingerprint identification area AA2 and the fingerprint identification area AA1 are arranged along the first direction X.

It should be noted that, the fingerprint identification area AA1 of the backlight module corresponds to the fingerprint identification area of the display device, the non-fingerprint identification area AA2 of the backlight module corresponds to the non-fingerprint identification area of the display device, the setting of the fingerprint identification area AA1 and the non-fingerprint identification area AA2 of the backlight module can be set according to the fingerprint identification area and the non-fingerprint identification area of the display device, this embodiment exemplarily shows that the non-fingerprint identification area AA2 at least partially surrounds the fingerprint identification area AA1, or the non-fingerprint identification area AA2 and the fingerprint identification area AA1 are arranged along the first direction X in the backlight module, in other embodiments of the present invention, the non-fingerprint identification area AA2 and the fingerprint identification area AA1 in the backlight module can also adopt other setting modes, which is not described in detail any more.

Fig. 10 is a schematic structural diagram of a backlight module according to the present invention, and fig. 11 is a schematic structural diagram of a plane of a light guide plate in the backlight module shown in fig. 10, referring to fig. 10 and fig. 11, optionally, wherein the backlight module further includes a light source 20, a reflective sheet 30, a diffusion sheet 40, and a brightness enhancement sheet 50;

the light guide plate 10 includes a first edge 14 extending in a first direction X, and a second edge 15 extending in a second direction Y, the first direction X and the second direction Y intersecting;

the light source 20 is located at one side of the first edge 14 or the second edge 15 of the light guide plate 10, the diffusion sheet 40 is located at one side of the light exit surface of the light guide plate 10, the brightness enhancement sheet 50 is located at one side of the diffusion sheet 40 far away from the light guide plate 10, and the reflection sheet 30 is located at one side of the light guide plate 20 far away from the diffusion sheet 40.

Specifically, with reference to fig. 10 and fig. 11, the backlight module provided in this embodiment further includes a light source 20, a reflector 30, a diffusion sheet 40, and a brightness enhancement sheet 50, the light source 20 is located at one side of the first edge 14 or the second edge 15 of the light guide plate 10, a light exit surface of the light source 20 may face a light entrance surface of the light guide plate 31, light guide points are disposed in the light guide plate 10, when an incident light irradiates each light guide point on the light guide plate 10, the incident light is diffused toward each angle, and then the light exits from the light exit surface of the light guide plate 10 by destroying a reflection condition, and meanwhile, the light transmitted inside the light guide plate 10 is refracted and reflected by the grooves 11, so that a transmission direction of the light is further changed, and the light is uniformly dispersed and emitted from the light exit surface of the light guide plate 10.

The reflective sheet 30 is located on a side of the light guide plate 20 away from the diffusion sheet 40, and the reflective sheet 30 is used for reflecting light irradiated from the light source 20 to the bottom surface of the light guide plate 10 into the light guide plate 10.

The diffusion sheet 40 is located at one side of the light exit surface of the light guide plate 10, the diffusion sheet 40 may include two parts, i.e., a base material and scattering particles, the base material may be a material with high light transmittance, such as PET/PC/PMMA, etc., the scattering particles are dispersed in the base material, and when the light of the backlight passes through the diffusion sheet 40, the light repeatedly passes through two media with different refractive indexes, i.e., the base material and the scattering particles, and multiple refraction, reflection and scattering phenomena occur, so as to provide a uniform surface light source.

The brightness enhancement sheet 50 is located on one side of the diffusion sheet 40 away from the light guide plate 10, the brightness enhancement sheet 50 may be a prism sheet, a surface of the prism sheet has a micro-prism structure, light emitted from the backlight passes through the prism sheet, the micro-prism structure scatters the light, and the light is finally converged and emitted in the front view direction under the circulation action of the backlight system, so as to achieve the brightness enhancement effect.

The present embodiment provides a display device, which includes a backlight module and a display panel located on a light-emitting surface of the backlight module, wherein the backlight module is the backlight module described above.

Referring to fig. 12 and 13, fig. 12 is a schematic structural diagram of a display device according to the present invention, and fig. 13 is a cross-sectional view of the display device shown in fig. 12 along D-D'. Fig. 12 and 13 provide a display device 1000 including a backlight module 100 and a display panel 200 located at a light exit surface of the backlight module 100, where the backlight module is the display panel 100 according to any of the embodiments of the present invention. The display device 1000 in the embodiments of fig. 12 and 13 is described by taking a mobile phone as an example, but it should be understood that the display device provided in the embodiments of the present invention may be other display devices with a display function, such as a computer, a television, a vehicle-mounted display device, and the present invention is not limited thereto. The display device provided by the embodiment of the present invention has the beneficial effects of the backlight module provided by the embodiment of the present invention, and specific reference may be made to the specific description of the backlight module in the foregoing embodiments, and details of the embodiment are not repeated herein.

With continuing reference to fig. 12 and 13, optionally, wherein the display device 1000 includes a display area AA, the display area AA includes a fingerprint identification area AA 1';

the display device 1000 further comprises a plurality of fingerprint identification units 300 disposed in the fingerprint identification area AA 1'.

Specifically, the display device 1000 includes a display area AA, the display area AA includes a fingerprint identification area AA1 ', a fingerprint identification area AA1 of the backlight module 100 corresponds to a fingerprint identification area AA 1' of the display device 1000, the display device 1000 further includes a plurality of fingerprint identification units 300 disposed in the fingerprint identification area AA1 ', the fingerprint identification units 300 are configured to identify a fingerprint, a plurality of second grooves 13 disposed in the fingerprint identification area AA1 of the light guide plate 10 are configured as curved grooves, so that the number of light rays incident into the display panel 200 via the fingerprint identification area AA1 in a unit area of the backlight module 100 is increased to be greater than the number of light rays incident into the display panel via the non-fingerprint identification area AA2, and the increased number of light rays can compensate the number of light rays shielded by the fingerprint identification unit 300, so that the light-emitting luminance of the display device 1000 in the fingerprint identification area AA1 and the non-fingerprint identification area AA 2' tends to be the same, the luminance uniformity of the display device 1000 is improved.

By the embodiment, the backlight module and the display device provided by the invention at least realize the following beneficial effects:

the backlight module provided by the invention comprises a light guide sheet, wherein the surface of one side of a light-emitting surface in the light guide sheet is provided with a plurality of grooves, the grooves comprise a plurality of first grooves positioned in a non-fingerprint identification area and a plurality of second grooves positioned in a fingerprint identification area, the first grooves are linear grooves, the second grooves are curved grooves, the length of the curved grooves is larger than that of the linear grooves in the same range, and the light condensation effect of the curved grooves is better, therefore, the plurality of second grooves positioned in the fingerprint identification area are set into the curved grooves, the quantity of light rays which are injected into a display panel through the fingerprint identification area in a unit area in the backlight module is increased, the quantity of the light rays which are injected into the display panel through the non-fingerprint identification area is larger than that of the light rays which are injected into the display panel through the non-fingerprint identification area, and the increased quantity of the light rays can compensate the quantity of the part of the light rays which are shielded by a fingerprint sensor, so that the luminous brightness of the display device in the fingerprint identification area and the non-fingerprint identification area tends to be the same, the brightness uniformity of the display device is improved.

Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A backlight module, comprising: a fingerprint identification area and a non-fingerprint identification area;

the backlight module further comprises a light guide plate, a plurality of grooves are formed in the surface of one side of the light guide plate, the grooves are located on the light emitting surface of the light guide plate, the grooves comprise a plurality of first grooves located in the non-fingerprint identification area and a plurality of second grooves located in the fingerprint identification area, the first grooves are linear grooves, the second grooves are curved grooves, and the lengths of the curved grooves are larger than the lengths of the linear grooves in the same range;

the vertical projection of the second grooves on the light-emitting surface of the light guide plate is in a circular ring structure or an elliptical ring structure, the centers of circles of the vertical projection of the second grooves on the light-emitting surface of the light guide plate are located at the same point, and the second grooves are arranged at equal intervals.

2. The backlight module according to claim 1,

the light guide plate includes a first edge extending in a first direction, and a second edge extending in a second direction, the first direction and the second direction intersecting;

the first grooves extend along the first direction, and the first grooves are arranged along the second direction.

3. The backlight module according to claim 2,

the groove width of the second grooves is 10-30 μm, the groove depth of the second grooves is 1-10 μm, and the distance between every two adjacent second grooves is 10-50 μm;

the groove width of the first grooves is 10-50 mu m, the groove depth of the first grooves is 1-10 mu m, and the distance between every two adjacent first grooves is 10-50 mu m.

4. The backlight module according to claim 1,

the groove comprises at least two first groove surfaces, and the first groove surfaces are of a plane structure;

or the groove comprises at least one second groove surface, and the second groove surface is of an arc surface structure.

5. The backlight module according to claim 4,

the groove is a V-shaped groove or a U-shaped groove.

6. The backlight module according to claim 1,

the non-fingerprint identification region at least partially surrounds the fingerprint identification region.

7. The backlight module according to claim 1,

the non-fingerprint identification area and the fingerprint identification area are arranged along a first direction.

8. The backlight module as claimed in claim 1, further comprising a light source, a reflective sheet, a diffusion sheet and a brightness enhancement sheet;

the light source is located on one side of the first edge or the second edge of the light guide plate, the diffusion sheet is located on one side of a light emergent face of the light guide plate, the brightness enhancement sheet is located on one side, far away from the light guide plate, of the diffusion sheet, and the reflection sheet is located on one side, far away from the diffusion sheet, of the light guide plate.

9. A display device, comprising:

the backlight module comprises a backlight module and a display panel positioned on a light-emitting surface of the backlight module, wherein the backlight module is the backlight module as claimed in any one of claims 1 to 8.

10. The display device according to claim 9,

the display device comprises a display area, and the display area comprises the fingerprint identification area;

the display device also comprises a plurality of fingerprint identification units arranged in the fingerprint identification area.