Patent Application
20210325731
This application claims the benefit of and priority to Chinese Patent Application No. 202010311259.3, filed on Apr. 20, 2020, the contents of which being incorporated by reference in their entirety herein.
One or more embodiments herein relate to the field of display technology and, in particular to a backlight module, a driving method thereof, and a display apparatus.
With the development of display technology, more and more people carry mobile products to read, study, or work in public places, and the demand for anti-peep display apparatuses is also increasing.
However, in the related art, the anti-peep display apparatus has various problems, such as large thickness, insufficient brightness, and unsatisfactory anti-peep effects at large viewing angles.
In view of this, the purpose of one or more embodiments of this specification is to provide a backlight module, a driving method thereof and a display apparatus, so as to solve the problems of low brightness and complicated process of the anti-peep display in the prior art.
Based on the foregoing objectives, one or more embodiments of this specification provide a backlight module, including:
a back plate, provided with a plurality of recessed portions and raised portions alternately distributed in sequence;
a reflective layer, provided on an inner wall of the recessed portion;
a first light source, provided at a bottom of the recessed portion; and
a second light source, provided on the raised portion.
Optionally, each of the recessed portions is a groove having an extension direction perpendicular to a direction along which any recessed portion faces toward a raised portion adjacent to the recessed portion, and the grooves are equidistantly distributed along the direction that any recessed portion faces toward a raised portion adjacent to the recessed portion.
Optionally, each of the recessed portions has a cup-shaped structure, and a plurality of the recessed portions are arranged in an array on the back plate.
Optionally, the bottom of the recessed portion is smaller than an opening of the recessed portion.
Optionally, the inner wall of the recessed portion includes one of a flat surface, a curved surface and a polygonal surface.
Optionally, the backlight module further includes:
acquiring a light source distance A between a center of the first light source and an opening of the recessed portion, a diameter B at the opening of the recessed portion, an angle C of the strongest light, a maximum reflected light angle D, and an irradiation distance L;
determining an overall dimension of the recessed portion and the maximum reflected light angle D based on the light source distance A and the diameter B at the opening;
determining a brightness distribution of the first light source based on the angle C of the strongest light, the maximum reflected light angle D and the irradiation distance L; and
determining a reflection curve based on the light source distance A, the diameter B at the opening, the angle C of the strongest light and the maximum reflected light angle D, and determining a shape of the inner wall of the recessed portion based on the reflection curve.
Optionally, a material of the reflective layer includes one of a specular reflective material, a diffuse reflective material, and a reflective material with a surface microstructure.
Optionally, each of the first light source and the second light source includes an LED light bar or an LED chip.
Optionally, a plurality of the first light sources are distributed in an array on the back plate; and a plurality of the second light sources are distributed in an array on the back plate.
Optionally, the first light source is further configured to emit light in a sharing state.
Optionally, the backlight module further includes:
a first circuit board, provided between the first light source and the recessed portion to realize a connection between the first light source and the driving circuit;
a second circuit board, provided between the second light source and the raised portion to realize a connection between the second light source and the driving circuit.
Optionally, the backlight module further includes:
a diffusion film, provided on a side of the second light source away from the back plate.
One or more embodiments of this specification further provide a driving method of a backlight module, including:
receiving a sharing state display instruction, and controlling the second light source to turn on based on the sharing state display instruction; or,
receiving an anti-peep state display instruction, and controlling the second light source to turn off and controlling the first light source to turn on based on the anti-peep state display instruction.
One or more embodiments of this specification further provide a display apparatus, including a display panel and the backlight module according to any one of the above.
It can be seen from the above that in the backlight module, the driving method thereof and the display apparatus provided in one or more embodiments of this specification, a plurality of recessed portions and raised portions alternately distributed in sequence are formed on a back plate, a first light source is provided inside the recessed portion, and a second light source is provided on the raised portion. In the sharing state, the second light source is controlled to emit light, so as to realize the requirement of sharing at a large viewing angle. In the anti-peep state, the second light source is turned off and only the first light source is controlled to emit light. The light emitted from the first light source will be blocked by the inner wall of the recessed portion and reflected out by the reflective layer, so that the included angle of the emitted light is smaller than the original angle of the light emitted from the first light source, which meets the requirements of the anti-peep state at a small viewing angle. The structure replaces the anti-peep film and PDLC in the prior art, and achieves the effect of reducing the viewing angle, so that the display apparatus manufactured by using the back plate of this embodiment can not only realize the anti-peep state with high uniformity and high collimation, but also realize the sharing state at a large viewing angle, and there is no light absorption loss, the brightness of both the anti-peep state and the sharing state will be increased, which greatly improves the light effect and enhances the visual effect.
In order to more clearly explain one or more embodiments of this specification or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. The accompanying drawings in the following description are only one or more embodiments of the present specification. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.
In order to make the objectives, technical solutions, and advantages of the present disclosure more clear, the present disclosure will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.
It should be noted that, unless otherwise defined, the technical terms or scientific terms used in one or more embodiments of this specification should be the usual meanings understood by those with ordinary skills in the field to which this disclosure belongs. “First”, “second”, and similar words used in one or more embodiments of this specification do not denote any order, quantity or importance, but are only used to distinguish different components. “Include”, “include”, and other similar words mean that the element or item appearing before the word covers the element or item listed after the word and their equivalents, but does not exclude other elements or items. Similar words such as “connected” or “coupled” are not limited to physical or mechanical connections, but may include electrical connections, regardless of direct or indirect connection. “Up”, “down”, “left”, “right”, etc. are only used to indicate the relative position relationship. When the absolute position of the described object changes, the relative position relationship may also change accordingly.
As shown in
As shown in
Currently, the third-generation anti-peep apparatus is also being developed. Compared with the second generation, the third-generation anti-peep apparatus removes the anti-peep film and replaces it with a collimating film. Its advantage is that the brightness will be improved (the brightness loss of the anti-peep film is 50%-60%), but the scheme process of the collimation system is complicated, and the requirements for processing accuracy are particularly high, and the anti-peep effect at the large viewing angle is still not ideal.
Based on the foregoing reasons, one or more embodiments of this specification provide a backlight module for realizing the anti-peep function of a display apparatus, and the anti-peep display apparatus has high uniformity and high collimation. As shown in
The back plate 1 is provided with a plurality of recessed portions 6 and raised portions 7 alternately distributed in sequence. In some optional embodiments, strip-shaped grooves or reflective cup-shaped recesses are provided on the back plate 1 having a certain thickness, to form a recessed portion 6 on the back plate 1, and a raised portion 7 is formed between two adjacent recessed portions 6.
The reflective layer (not shown in
The first light source 2 is provided at a bottom of the recessed portion 6, and the first light source 2 is configured to emit light in an anti-peep state. As shown in
The second light source 3 is arranged on the raised portion and configured to not emit light in the anti-peep state and emit light in the sharing state. As shown in
In this embodiment, a plurality of recessed portions 6 and raised portions 7 alternately distributed in sequence are formed on a back plate 1, a first light source 2 is provided inside the recessed portion 6, and a second light source 3 is provided on the raised portion 7. In the sharing state, the second light source 3 is controlled to emit light, so as to realize the requirement of sharing at a large viewing angle. In the anti-peep state, the second light source 3 is turned off and only the first light source 2 is controlled to emit light. The light emitted from the first light source 2 will be blocked by the inner wall of the recessed portion 6 and reflected out by the reflective layer, so that the included angle of the emitted light is smaller than the original angle of the light emitted from the first light source 2, which meets the requirements of the anti-peep state at a small viewing angle. The structure replaces the anti-peep film and PDLC in the prior art, and achieves the effect of reducing the viewing angle, so that the display apparatus manufactured by using the back plate of this embodiment can not only realize the anti-peep state with high uniformity and high collimation, but also realize the sharing state at a large viewing angle, and there is no light absorption loss, the brightness of both the anti-peep state and the sharing state will be increased, which greatly improves the light effect and enhances the visual effect.
Optionally, in the sharing state, the first light source 2 may be configured to not emit light, or may be configured to emit light. When the first light source 2 is configured to emit light, the light emission brightness in the sharing state can be improved.
Optionally, in the foregoing embodiment, the angles of light emitted from the first light source 2 and the second light source 3 may be the same or different. Optionally, in order to facilitate the selection of the light source elements and improve the efficiency of the installation of the first light source 2 and the second light source 3, the angles of light emitted from the first light source 2 and the second light source 3 are the same.
Optionally, the back plate 1 in this embodiment can be a component that replaces the substrate (FPC/glass) in the conventional surface light source. The first light source 2 and the second light source 3 are glued together with the TFOG (Touch FPC On Glass) tape during processing.
In some optional embodiments of this specification, each of the recessed portions 6 is a groove having an extension direction perpendicular to a direction along which any recessed portion 6 faces toward a raised portion 7 adjacent to the recessed portion 6, and the grooves are equidistantly distributed along the direction that any recessed portion 6 faces toward a raised portion 7 adjacent to the recessed portion 6. As shown in
In other optional embodiments, as shown in
Optionally, as shown in
In some optional embodiments of the present specification, the inner wall of the recessed portion 6 includes one of various types such as a flat surface, a curved surface, and a polygonal surface. The angle of light emitted from the first light source 2 is controlled by the shape of the inner wall of the recessed portion 6, so as to meet the requirements of the anti-peep angle. For example, when the inner wall of the recessed portion 6 is a curved surface, the angle of light emitted from the first light source 2 is determined by the curvature of the curved surface. The shape of the recessed portion 6 is determined as long as the curvature of the inner wall of the recessed portion 6 that meets the light efficiency requirements is calculated. Since the shape of the recessed portion 6 is mainly determined by the light source distance between the center of the first light source 2 and the opening of the recessed portion 6 and the diameter at the opening of the recessed portion 6, the brightness uniformity effect of the first light source 2 is determined by the angle of the strongest light, the maximum reflected light angle and the irradiation distance. The maximum reflected light angle is determined by the curvature of the inner wall curved surface of the recessed portion 6. Therefore, the method of confirming the inner wall shape of the recessed portion includes:
as shown in
In some optional embodiments, the reflective layer is formed by coating a highly reflective material. The material of the reflective layer includes one of a specular reflective material (such as silver, aluminum, etc.), a diffuse reflective material (such as white ink, white glue, resin, etc.), and a reflective material with a surface microstructure (such as circular dots, multilayer film systems, Fresnel prism structure, etc.). The use of highly reflective materials further improves the reflection efficiency of the reflective layer and reduces the light loss.
Optionally, each of the first light source 2 and the second light source 3 includes an LED light bar or an LED chip, and the LED light type includes but not limited to Lambertian light emission and any other light types.
Optionally, a plurality of the first light sources 2 are distributed in an array on the back plate 1; and a plurality of the second light sources 3 are distributed in an array on the back plate 1.
Optionally, the backlight module described in the embodiment of this specification further includes: a first circuit board 5, provided between the first light source 2 and the recessed portion 6 to realize a connection between the first light source 2 and the driving circuit; a second circuit board 4, provided between the second light source 3 and the raised portion 7 to realize a connection between the second light source 3 and the driving circuit. In the embodiment, the first circuit board 5 and the second circuit board 4 may be FPC substrates, PCB substrates, glass, or the like.
Optionally, the backlight module described in the embodiment of this specification further includes a diffusion film provided on a side of the second light source 2 away from the back plate 1, i.e., a diffusion film having a specific concentration is provided between the back plate 1 and the display panel. The anti-peep viewing angle may be adjusted to be ±30°, which is the same as the existing 3M anti-peep film, and the light efficiency is significantly improved.
In an optional embodiment of this specification, the depth of the recessed portion 6 is 300 um. In this embodiment, in combination with the light type of the first light source 2, when the first light source 2 is turned on, the light emitted from the first light source 2 is reflected by the reflective layer, and the shape and curvature of the inner wall of the recessed portion 6 can be simulated by the software, and the simulated illumination pattern is shown in
In the sharing state, when only the second light source 3 is turned on or both the first light source 2 and the second light source 3 are turned on at the same time, the corresponding brightness distribution simulation result is shown in
Other embodiments of this specification provide a driving method of a backlight module, including: receiving a sharing state display instruction, and controlling the second light source to turn on based on the sharing state display instruction; or, receiving an anti-peep state display instruction, and controlling the second light source to turn off and controlling the first light source to turn on based on the anti-peep state display instruction.
In this embodiment, when a sharing state display instruction is received, the driver IC detects the working state of the second light source 3 and turns on the second light source 3 if the second light source 3 is not turned on, so that the emitted light diverges, and the sharing state display requirement is realized. The first light source 2 can also be controlled to turn on when necessary, to increase the display brightness.
When the anti-peep state display instruction control is received, the driver IC detects the working state of the first light source 2 and the second light source 3, and controls the second light source 3 to turn off and controls the first light source 2 to turn on according to the current working state, so that the emitted light is narrowed to meet the anti-peep state display requirements.
Other embodiments of this specification further provide a display apparatus. As shown in
Those of ordinary skill 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 (including the claims) is limited to these examples. Under the idea of the present disclosure, the above embodiments or the technical features in different embodiments can also be combined, the steps can be implemented in any order. There are many other changes in different aspects of one or more embodiments of this specification as described above, and they are not included in the details for the sake of brevity.
In addition, in order to simplify the description and discussion, and in order not to make one or more embodiments of this specification difficult to understand, the accompanying drawings may or may not show well-known power supply/ground connection in relation to integrated circuit (IC) chips and other components. In addition, the apparatus may be shown in the form of a block diagram, in order to avoid making one or more embodiments of this specification difficult to understand, and this also takes into account the fact that the details about the implementation of these block diagram apparatuses highly depends on the platform that will implement one or more embodiments of the present description (that is, these details should be fully within the understanding of those skilled in the art). In the case where specific details (for example, circuits) are illustrated to describe exemplary embodiments of the present disclosure, it is apparent to those skilled in the art that one or more embodiments of this specification may be implemented without these specific details or when these specific details are changed. Therefore, these descriptions should be considered illustrative rather than restrictive.
Although the present disclosure has been described in conjunction with specific embodiments of the present disclosure, based on the foregoing description, many substitutions, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art. For example, other memory architectures (e.g., dynamic RAM (DRAM)) can use the discussed embodiments.
One or more embodiments of this specification are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omission, modification, equivalent replacement, improvement, etc. made within the spirit and principle of one or more embodiments of the present specification shall be included in the protection scope of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202010311259.3 | Apr 2020 | CN | national |
