Fresnel lens, backlight module, image generation device, display system and mobile device

Abstract

The embodiment of the utility model provides a Fresnel lens, a backlight module, an image generation device, a display system and mobile equipment, and the Fresnel lens comprises a first Fresnel surface and a second Fresnel surface, the first Fresnel surface comprises a first sawtooth part, a first projection part and a second sawtooth part which are arranged along a first direction, the first sawtooth part and the second sawtooth part are arranged on the two opposite sides of the first protruding part in the first direction. The second Fresnel surface comprises a third sawtooth part, a second protruding part and a fourth sawtooth part which are arranged in the second direction. The third sawtooth part and the fourth sawtooth part are arranged on the two opposite sides of the second protruding part in the second direction. The first direction is perpendicular to the second direction. The Fresnel structures are arranged on the two Fresnel faces in the direction perpendicular to each other, the problem that light is excessively focused in the center can be effectively solved, and the light uniformizing effect is improved.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the field of optical technology, in particular to a Fresnel lens, a backlight module, an image generating device, a display system and a mobile device. BACKGROUND

[0002] The backlight illumination system in the head-up display is used to illuminate the image information containing the instruments, navigation, so that this part of information can be projected to the vicinity of the driver's line of sight through the imaging light path, avoiding the driver's frequent looking down at the instrument panel while driving. The virtual image projected in front of the windshield of the car must require the brightness uniformity perceived by the human eye, avoid glare and ensure the safety of driving.

[0003] However, the Fresnel lens with a Fresnel surface is usually used for uniform light in the current head-up display, and the light will be too focused in the center after passing through the Fresnel lens, resulting in poor uniform light effect. CONTENT OF THE UTILITY MODEL

[0004] The embodiments of the present application provide a Fresnel lens, a backlight module, an image generating device, a display system and a mobile device, and the uniform light effect can be improved by using the Fresnel lens provided by the present application.

[0005] In a first aspect, the embodiments of the present application provide a Fresnel lens, which comprises: a first Fresnel surface and a second Fresnel surface, the first Fresnel surface comprises a first sawtooth part, a first convex part and a second sawtooth part arranged along a first direction, the first sawtooth part and the second sawtooth part are arranged on opposite sides of the first convex part along the first direction; the second Fresnel surface comprises a third sawtooth part, a second convex part and a fourth sawtooth part arranged along a second direction, the third sawtooth part and the fourth sawtooth part are arranged on opposite sides of the second convex part along the second direction; and the first direction is perpendicular to the second direction.

[0006] In one or more embodiments, the first sawtooth part comprises a plurality of first strip sawtooth structures arranged in sequence along the first direction, the distance between adjacent two first strip sawtooth structures increases along the first direction, the second sawtooth part comprises a plurality of second strip sawtooth structures arranged in sequence along the first direction, the distance between adjacent two second strip sawtooth structures decreases along the first direction; and / or, the third sawtooth part comprises a plurality of third strip sawtooth structures arranged in sequence along the second direction, the distance between adjacent two third strip sawtooth structures increases along the second direction, the fourth sawtooth part comprises a plurality of fourth strip sawtooth structures arranged in sequence along the second direction, the distance between adjacent two fourth strip sawtooth structures decreases along the second direction.

[0007] In one or more embodiments, the Fresnel lens further includes a substrate; the substrate has a first surface and a second surface, the first surface being a first Fresnel surface and the second surface being a second Fresnel surface.

[0008] Secondly, embodiments of this application also provide a backlight module, which includes: a light source and a Fresnel lens as described in any of the first aspects, arranged sequentially; a first Fresnel surface of the Fresnel lens is disposed close to the light source, and a second Fresnel surface of the Fresnel lens is disposed away from the light source.

[0009] In one or more embodiments, the backlight module further includes a reflector; the light source is disposed on the light-incident side of the reflector, and the Fresnel lens is disposed on the light-outcident side of the reflector.

[0010] In one or more embodiments, in a cross-section passing through the central axis of the reflector, the reflector has two contour lines symmetrical about the central axis, each contour line comprising two connected straight lines with different inclination angles relative to the central axis.

[0011] In one or more embodiments, the backlight module further includes a diffusion device; the diffusion device is disposed on the light-emitting side of the Fresnel lens.

[0012] Thirdly, embodiments of this application also provide an image generation apparatus, which includes: a display panel and a backlight module as described in any of the second aspects; the backlight module is disposed on the light-incident side of the display panel.

[0013] Fourthly, embodiments of this application also provide a display system, which includes: an emission device and an image generation device as described in the third aspect; the image generation device is disposed on the light-incident side of the emission device.

[0014] Fifthly, embodiments of this application also provide a mobile device, the mobile device comprising: an image generating apparatus as described in the third aspect, the image generating apparatus being configured to output an image to a first target area, and / or, including a display system as described in the fourth aspect; the display system being configured to output an image to a second target area.

[0015] The beneficial effects of this application embodiment are as follows: This application embodiment provides a Fresnel lens, a backlight module, an image generation device, a display system, and a mobile device, including a first Fresnel surface and a second Fresnel surface. The first Fresnel surface includes a first serrated portion, a first protrusion, and a second serrated portion arranged along a first direction, with the first serrated portion and the second serrated portion disposed on opposite sides of the first protrusion along the first direction. The second Fresnel surface includes a third serrated portion, a second protrusion, and a fourth serrated portion arranged along a second direction, with the third serrated portion and the fourth serrated portion disposed on opposite sides of the second protrusion along the second direction. The first direction is perpendicular to the second direction. By arranging the Fresnel structure on the two Fresnel surfaces in mutually perpendicular directions, the problem of light being overly focused at the center can be effectively avoided, improving the light uniformity effect. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1 A three-dimensional structural view of a Fresnel lens provided in an embodiment of this application;

[0018] Figure 2 for Figure 1 The image shows a three-dimensional view of the Fresnel lens from another angle.

[0019] Figure 3 for Figure 1 The side view of the Fresnel lens shown;

[0020] Figure 4 for Figure 1 The top view of the Fresnel lens shown;

[0021] Figure 5 A structural block diagram of a backlight module provided in an embodiment of this application;

[0022] Figure 6 A structural diagram of a backlight module provided in an embodiment of this application;

[0023] Figure 7 A cross-sectional schematic diagram of a reflector cup provided in an embodiment of this application;

[0024] Figure 8 This is a structural block diagram of an image generation apparatus provided in an embodiment of this application;

[0025] Figure 9 This is a structural block diagram of a display system provided in an embodiment of this application. Detailed Implementation

[0026] To facilitate understanding of this application, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "electrically connected" to another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "upper," "lower," "inner," "outer," "bottom," etc., used in this specification indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items. Furthermore, technical features involved in the different embodiments of this application described below may be combined with each other as long as they do not conflict with each other.

[0028] In a first aspect, embodiments of this application provide a Fresnel lens 10, which includes a first Fresnel surface and a second Fresnel surface.

[0029] See Figure 1 and Figure 2 The first Fresnel surface includes a first serrated portion 11, a first protrusion 12, and a second serrated portion 13 disposed along a first direction x. The first serrated portion 11 and the second serrated portion 13 are disposed on opposite sides of the first protrusion 12 along the first direction x. The second Fresnel surface includes a third serrated portion 14, a second protrusion 15, and a fourth serrated portion 16 disposed along a second direction y. The third serrated portion 14 and the fourth serrated portion 16 are disposed on opposite sides of the second protrusion 15 along the second direction y. The first direction x is perpendicular to the second direction y.

[0030] The first serrated portion 11, the second serrated portion 13, the third serrated portion 14, and the fourth serrated portion 16 refer to a series of structures with a serrated shape, and the first protrusion 12 and the second protrusion 15 refer to convex surface structures. Each serrated portion and each protrusion can be used to change the direction of light.

[0031] The first serrated portion 11 and the second serrated portion 13 may be symmetrical or asymmetrical with respect to the first protrusion 12, and the third serrated portion 14 and the fourth serrated portion 16 may be symmetrical or asymmetrical with respect to the second protrusion 15.

[0032] By arranging Fresnel structures on two Fresnel surfaces in mutually perpendicular directions, compared to a Fresnel lens 10 using only one Fresnel surface, the Fresnel lens 10 provided in this application effectively avoids the problem of light being overly focused at the center. Furthermore, the Fresnel structures on the two Fresnel surfaces are independent of each other, allowing for individual adjustment of the serrated and protruding portions on the first and second Fresnel surfaces. This enables individual adjustment of the size of the light spot emitted after passing through the Fresnel lens 10 in the first direction x and the second direction y, for example, collimating the light into a slightly elliptical or circular shape. Subsequently, when this Fresnel lens 10 is applied to the backlight module 100, it can perform angular diffusion and light homogenization, and avoid the problem of light being overly focused at the center, improving light energy utilization and image uniformity.

[0033] In some of these embodiments, see Figure 3 The first serrated portion 11 includes a plurality of first strip serrated structures 111 arranged sequentially along the first direction x, and the distance between two adjacent first strip serrated structures 111 increases along the first direction x. The second serrated portion 13 includes a plurality of second strip serrated structures 131 arranged sequentially along the first direction x, and the distance between two adjacent second strip serrated structures 131 decreases along the first direction x.

[0034] The first serrated structure 111 includes a first serrated surface S1 and a second serrated surface S2. The first serrated surface S1 and the second serrated surface S2 intersect at a line of intersection. The included angle between the first serrated surface S1 and the second serrated surface S2 can be adjusted according to actual needs. The distance between two adjacent first serrated structures 111 refers to the distance between the lines of intersection of two adjacent first serrated structures 111.

[0035] Similarly, the second serrated structure 131 includes a third serrated surface S3 and a fourth serrated surface S4. The third serrated surface S3 and the fourth serrated surface S4 intersect at a line of intersection, and the included angle between the third serrated surface S3 and the fourth serrated surface S4 can be adjusted according to actual needs. The distance between two adjacent second serrated structures 131 refers to the distance between the lines of intersection of two adjacent second serrated structures 131.

[0036] In this embodiment, by adjusting the distance between two adjacent first strip sawtooth structures 111 and the distance between two adjacent second strip sawtooth structures 131, the shape of the strip sawtooth structure can be flexibly changed to control the direction of light.

[0037] In some of these embodiments, see Figure 4 The third sawtooth portion 14 includes a plurality of third strip sawtooth structures 141 arranged sequentially along the second direction y, and the distance between two adjacent third strip sawtooth structures 141 increases along the second direction y. The fourth sawtooth portion 16 includes a plurality of fourth strip sawtooth structures 161 arranged sequentially along the second direction y, and the distance between two adjacent fourth strip sawtooth structures 161 decreases along the second direction y.

[0038] The third serrated structure 141 includes a fifth serrated surface S5 and a sixth serrated surface S6. The fifth serrated surface S5 and the sixth serrated surface S6 intersect at a line of intersection. The included angle between the fifth serrated surface S5 and the sixth serrated surface S6 can be adjusted according to actual needs. The distance between two adjacent third serrated structures 141 refers to the distance between the lines of intersection of two adjacent third serrated structures 141.

[0039] Similarly, the fourth serrated structure 161 includes a seventh serrated surface S7 and an eighth serrated surface S8. The seventh serrated surface S7 and the eighth serrated surface S8 intersect at a line of intersection. The included angle between the seventh serrated surface S7 and the eighth serrated surface S8 can be adjusted according to actual needs. The distance between two adjacent fourth serrated structures 161 refers to the distance between the lines of intersection of two adjacent fourth serrated structures 161.

[0040] In this embodiment, by adjusting the distance between two adjacent third stripe sawtooth structures 141 and the distance between two adjacent fourth stripe sawtooth structures 161, the shape of the stripe sawtooth structure can be flexibly changed to control the direction of light.

[0041] In some embodiments, the Fresnel lens 10 further includes a substrate; the substrate has a first surface and a second surface, the first surface being a first Fresnel surface and the second surface being a second Fresnel surface.

[0042] A substrate is a transparent material with a certain refractive index, which can be used to transmit light.

[0043] By placing the first Fresnel surface and the second Fresnel surface on the same substrate, the volume of the Fresnel lens 10 can be saved, and the impact and vibration resistance of the Fresnel lens 10 can be improved, thereby enhancing the stability of the Fresnel lens 10 in various complex environments.

[0044] Secondly, embodiments of this application provide a backlight module, see [link to relevant documentation]. Figure 5The backlight module 100 includes: a light source 20 and a Fresnel lens 10 as described in any embodiment of the first aspect, arranged sequentially. The first Fresnel surface of the Fresnel lens 10 is disposed close to the light source 20, and the second Fresnel surface of the Fresnel lens 10 is disposed away from the light source 20.

[0045] In this embodiment, the Fresnel lens 10 has the same structure and function as the Fresnel lens 10 described in any embodiment of the first aspect, and will not be repeated here.

[0046] The light source 20 includes light-emitting diode (LED) beads, electroluminescent devices, cold cathode fluorescent lamps, laser diodes, or other light-emitting components that can be used to provide light for illumination.

[0047] In this backlight module 100, by using the Fresnel lens 10 provided in this application, the problem of light being too focused on the center can be effectively avoided, thereby improving the collimation and uniform light effect.

[0048] In some of these embodiments, see Figure 6 The backlight module 100 also includes a reflector 30. The light source 20 is located on the light-incident side of the reflector 30, and the Fresnel lens 10 is located on the light-outcident side of the reflector 30.

[0049] The reflector cup 30, typically cup-shaped, receives light emitted from the light source 20 and collimates this light through its special reflective surface, thus focusing the emitted light at a specific angle and achieving pre-collimation. Furthermore, the reflector cup 30 reflects and focuses the light from the light source 20 through its reflective surface, reducing light waste and improving light utilization. In addition, when used in conjunction with the Fresnel lens 10, it can improve the uniformity and brightness of the lighting light, thereby enhancing the lighting quality.

[0050] In some of these embodiments, see Figure 7 On the cross-section passing through the central axis m of the reflector 30, the reflector 30 has a contour line n and a contour line p that are symmetrical about the central axis m. The contour line n includes connected straight lines n1 and n2, and the straight lines n1 and n2 have different inclination angles relative to the central axis m. The contour line p includes connected straight lines p1 and p2, and the straight lines p1 and p2 have different inclination angles relative to the central axis m. The straight lines n1 and p1 have the same inclination angle relative to the central axis m, and the straight lines n2 and p2 have the same inclination angle relative to the central axis m.

[0051] Specifically, the reflector cup 30 has a first reflective surface and a second reflective surface. The first reflective surface is rotationally symmetric about the central axis m, and the second reflective surface is rotationally symmetric about the central axis m. Lines n1 and p1 are the intercepts of the first reflective surface on the cross-section passing through the central axis m of the reflector cup 30, respectively. Lines n2 and p2 are the intercepts of the second reflective surface on the cross-section passing through the central axis m of the reflector cup 30, respectively.

[0052] In practical applications, the shape of the reflector cup in the cross-section can be designed according to the actual direction of light. For example, in this embodiment, it is designed with a zigzag shape to improve the reflection and focusing effect of light, thereby improving the illumination brightness and illumination distance of the backlight module.

[0053] In some of these embodiments, see Figure 6 The backlight module 100 also includes a diffuser 40; the diffuser 40 is disposed on the light-emitting side of the Fresnel lens 10.

[0054] The diffuser 40 further diffuses the light, increasing its distribution range on the output surface and improving uniform light distribution. The diffused light from the diffuser 40 can be directly used to illuminate the display panel, transmitting the light onto the panel at a predetermined angle. The diffuser 40 can utilize devices such as a diffusion film.

[0055] Thirdly, embodiments of this application also provide an image generation apparatus, see below. Figure 8 The image generation apparatus 1000 includes: a display panel 200 and a backlight module 100 as described in any of the above embodiments. The backlight module 100 is disposed on the light-incident side of the display panel 200.

[0056] In this embodiment, the backlight module 100 has the same structure and function as the backlight module 100 described in any embodiment of the second aspect, and will not be repeated here.

[0057] The display panel 200 is configured to receive illumination light emitted from the backlight module 100 and generate a virtual image. The virtual image can be a color image or a black and white image. Specifically, the color of the illumination light output by the backlight module 100 and / or the type of the display panel 200 can be set according to actual needs. For example, the display panel 200 can be a liquid crystal display (LCD).

[0058] In the image generating apparatus 1000, light output from the backlight module 100 is projected onto the display panel 200, which then excites the generation of an image beam.

[0059] Fourthly, embodiments of this application also provide a display system, see below. Figure 9The display system 10000 includes an emission device 2000 and an image generating device 1000 as described in the third aspect. The image generating device 1000 is located on the light-incident side of the emission device 2000.

[0060] In this embodiment, the image generating apparatus 1000 has the same structure and function as the image generating apparatus 1000 described in any embodiment of the third aspect, and will not be repeated here.

[0061] The display system 1000 may be a projector, head-up display, light field screen, projection vehicle light, wearable / head-mounted device, virtual reality device, augmented reality device, etc. The emission device 2000 may include a projection lens, reflector, etc. This application embodiment does not specifically limit the display system.

[0062] For example, the display system 1000 is an augmented reality head-up display (AR HUD). The emitting device includes a mirror mechanism, which includes at least one mirror. The mirror can be a curved or flat mirror. The mirror can be rotatable or non-rotatable. The image generating device projects image light onto the mirror mechanism. The mirror mechanism deflects the image light and finally projects the image light onto the target area for image display.

[0063] Fifthly, embodiments of this application also provide a mobile device comprising: an image generating apparatus as described in the third aspect, the image generating apparatus being configured to output an image to a first target region.

[0064] In this embodiment, the image generating apparatus has the same structure and function as the image generating apparatus described in any embodiment of the third aspect, and will not be repeated here.

[0065] Mobile devices can be vehicles such as cars, ships, and airplanes, or they can be robots. The primary target area can be areas that can transmit light, such as windshields, sunroofs, windows, reflective panels, and the ground.

[0066] For example, in a car, the primary target area is the windshield. A black area is set at the bottom or other location of the windshield. An image is projected onto the windshield by an image generating device 1000, displaying information within this specific area. This is PHUD, or Panoramic Head-Up Display. As an innovation in HUD technology, PHUD reduces errors caused by optical reflections, resulting in higher display clarity and stability, and more accurate information reading.

[0067] In a sixth aspect, embodiments of this application also provide a mobile device, the mobile device comprising: a display system as described in the fourth aspect; the display system being configured to output an image to a second target area.

[0068] In this embodiment, the display system has the same structure and function as the display system described in any embodiment of the fourth aspect, and will not be repeated here.

[0069] Mobile devices can be vehicles such as cars, ships, and airplanes, or mobile devices such as robots. The second target area can be areas that can transmit light, such as windshields, sunroofs, car windows, reflective panels, and the ground.

[0070] For example, when the display system is an augmented reality head-up display (AR HUD) and the mobile device is a car, the target area includes one or more of the car's windshield, windows, and sunroof. If the display system is a light field screen, the target area is a transflective panel, which can be located in the passenger seat, the back of the seat, the headrest, etc., without limitation.

[0071] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this application as described above, which are not provided in detail for the sake of brevity; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A Fresnel lens, characterized in that, include: Including the first Fresnel plane and the second Fresnel plane, The first Fresnel surface includes a first serrated portion, a first protrusion portion and a second serrated portion disposed along a first direction, wherein the first serrated portion and the second serrated portion are disposed on opposite sides of the first protrusion portion along the first direction. The second Fresnel surface includes a third serrated portion, a second protrusion, and a fourth serrated portion disposed along a second direction, wherein the third serrated portion and the fourth serrated portion are disposed on opposite sides of the second protrusion along the second direction; The first direction is perpendicular to the second direction.

2. The Fresnel lens according to claim 1, characterized in that, The first sawtooth portion includes a plurality of first strip sawtooth structures arranged sequentially along a first direction, and the distance between two adjacent first strip sawtooth structures increases along the first direction. The second sawtooth portion includes a plurality of second strip sawtooth structures arranged sequentially along the first direction, and the distance between two adjacent second strip sawtooth structures decreases along the first direction. And / or, the third sawtooth portion includes a plurality of third strip sawtooth structures arranged sequentially along the second direction, the distance between two adjacent third strip sawtooth structures increasing along the second direction, and the fourth sawtooth portion includes a plurality of fourth strip sawtooth structures arranged sequentially along the second direction, the distance between two adjacent fourth strip sawtooth structures decreasing along the second direction.

3. The Fresnel lens according to claim 1 or 2, characterized in that, The Fresnel lens also includes a substrate; The substrate has a first surface and a second surface, the first surface being a first Fresnel surface and the second surface being a second Fresnel surface.

4. A backlight module, characterized in that, include: A light source and a Fresnel lens as described in any one of claims 1-3 are arranged sequentially. The first Fresnel surface of the Fresnel lens is positioned close to the light source, and the second Fresnel surface of the Fresnel lens is positioned away from the light source.

5. The backlight module according to claim 4, characterized in that, The backlight module also includes a reflector; The light source is located on the light-incident side of the reflector, and the Fresnel lens is located on the light-outcident side of the reflector.

6. The backlight module according to claim 5, characterized in that, In a cross-section passing through the central axis of the reflector, the reflector has two contour lines symmetrical about the central axis, each contour line comprising two connected straight lines with different inclination angles relative to the central axis.

7. The backlight module according to any one of claims 4-6, characterized in that, The backlight module also includes a diffusion device; The diffusion device is located on the light-emitting side of the Fresnel lens.

8. An image generation apparatus, characterized in that, include: Display panel, backlight module as described in any one of claims 4-7; The backlight module is located on the light-incident side of the display panel.

9. A display system, characterized in that, include: The emission device and the image generation device as described in claim 8; The image generation device is located on the light-incident side of the emission device.

10. A mobile device, characterized in that, include: The image generating apparatus of claim 8, wherein the image generating apparatus is configured to output an image to a first target region; And / or, including the display system as claimed in claim 9, wherein the display system is configured to output an image to a second target area.

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