Flexible light control three-dimensional display system based on optical waveguide

Abstract

The invention discloses a flexible light control three-dimensional display system based on an optical waveguide, which relates to the technical field of three-dimensional display and comprises a lateral backlight structure, an optical waveguide structure, a light control structure and a display unit, a plurality of coupling units are arranged on the optical waveguide structure; the light control structure comprises a plurality of light control units. According to the system, the light control structure is arranged on the inner side of the display unit, and each light control unit can be very small, so that the size of each light control unit can be smaller than or equal to the size of one pixel on the display unit, and the system can flexibly control light in three-dimensional display due to the special structure, so that the display quality is improved. The method has great significance in improving various performances of three-dimensional light field display.

Description

Technical Field

[0001] The present invention relates to the technical field of three-dimensional display, and in particular to a flexible light-control three-dimensional display system based on optical waveguide. Background Art

[0002] Compared with traditional two-dimensional flat display technology, three-dimensional display technology restores the real three-dimensional visual world as much as possible and can provide a natural and realistic viewing experience. It has received widespread attention in recent years. Specifically, three-dimensional light field display technology is considered to be one of the most promising three-dimensional display technologies with broad application prospects. Unlike three-dimensional display based on binocular parallax, light field display can reconstruct the real three-dimensional light field distribution and provide viewers with a real and natural three-dimensional perception. In addition, this technology can achieve a 3D effect with true color. Viewing angle and resolution are important indicators that affect display quality in three-dimensional display. Ideal 3D display technology can provide viewers with a visual sense close to the real world.

[0003] However, current light field display technology has display problems such as uneven spatial resolution and difficulty in improving angular resolution. This is mainly due to the lack of freedom and flexibility in light control in existing display solutions. Figure 2 As shown, LCD and cylindrical lens array are arranged in sequence on the optical path, and each cylindrical lens covers multiple sub-pixels. Due to the optical aberration of the cylindrical lens, crosstalk will be caused, so the light control is not free and flexible, and it is difficult to achieve flexible light control, resulting in low accuracy, clarity and realism of the display effect, difficulty in controlling the angular resolution, limitation of the display depth and other problems, which seriously affect the overall display effect of the three-dimensional display system. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a three-dimensional display system with flexible light control based on optical waveguide, which solves the problem that the prior three-dimensional display technology is difficult to achieve flexible light control.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0006] Provided is a flexible light-control three-dimensional display system based on an optical waveguide, which comprises an edge-entry backlight structure, an optical waveguide structure, a light-control structure and a display unit; a plurality of coupling units are arranged on the optical waveguide structure; the light-control structure comprises a plurality of light-control units; wherein:

[0007] The side-entry backlight structure is used to provide a light source for the optical waveguide structure from the side;

[0008] An optical waveguide structure, used for reflecting light entering therein and allowing part of the light to escape from the coupling unit;

[0009] A coupling unit, used to make the light entering it escape from different angles and directions in a scattered and reflected manner; all coupling units form a dot matrix light source array;

[0010] A light control unit, located between the coupling unit and the display unit, is used to control the light by deflecting the light escaping from the coupling unit, so that the light passing through the light control unit projects each sub-pixel on the display unit into a body pixel, thereby realizing three-dimensional display;

[0011] A display unit, used for providing display information;

[0012] The light is flexibly controlled by controlling the relative position relationship between the coupling unit and the light control unit.

[0013] The beneficial effects of the present invention are as follows: the system places the light control structure on the inner side of the display unit, and each light control unit can be made very small, so that the size of each light control unit can be less than or equal to the size of a pixel on the display unit. Such a special structure enables the system to achieve flexible light control in three-dimensional display, which is of great significance for improving various performances of three-dimensional light field display.

[0014] Furthermore, the size of each light control unit is smaller than or equal to the size of a pixel.

[0015] Furthermore, the size of a single coupling unit is less than or equal to one third of the size of the light control unit.

[0016] The beneficial effect of adopting the above further solution is that the light control unit can be accurately fitted on the optical waveguide structure to achieve joint light control.

[0017] Furthermore, the constraint relationship between the coupling unit and the light control unit corresponding to the same viewpoint is:

[0018]

[0019] Wherein d is the period of the coupling unit; D is the period of the light control unit; L is the viewing distance; and l is the distance between the light control unit and the coupling unit.

[0020] The beneficial effect of adopting the above further solution is that the constraint relationship enables the correct display content to be viewed at a viewpoint by filling in a parallax image corresponding to a viewpoint on the display unit.

[0021] Furthermore, when there are multiple coupling units corresponding to viewpoints under the same light control unit, the following constraints apply:

[0022]

[0023] Wherein m is the distance between the centers of any two viewpoints; n is the minimum spacing between the coupling units corresponding to the two viewpoints; L is the viewing distance; and l is the distance between the light control unit and the coupling unit.

[0024] The beneficial effect of adopting the above further scheme is: since three-dimensional display often has multiple viewpoints, there is more than one positional relationship between the light control unit and the coupling unit. This constraint can control the direction of light by adjusting the relative position of the coupling unit and the light control unit, thereby achieving a flexible light control effect.

[0025] Furthermore, when there is only one coupling unit corresponding to one viewpoint under the same light control unit, the following constraints apply:

[0026]

[0027] Where m * is the distance between the centers of two adjacent viewpoints; n * is the minimum spacing between the coupling units corresponding to the two viewpoints; p is the aperture of the light control unit; L is the viewing distance; l is the distance between the light control unit and the coupling unit.

[0028] The beneficial effects of adopting the above further solution are: flexibly controlling the angular resolution of the three-dimensional display, improving the display depth of the three-dimensional display, making full use of the display information, and improving the three-dimensional display effect.

[0029] Furthermore, the coupling unit is an optical coupling hole, and the inner wall of the optical coupling hole is frosted.

[0030] The beneficial effect of adopting the above further solution is that the light beam can be scattered more effectively, thereby achieving coupling between the optical waveguide structure and the light control structure.

[0031] Furthermore, the light control unit includes a slit grating, a cylindrical lens, a dot lens, a micro-hole, a common lens and / or a compound lens.

[0032] Furthermore, the display unit includes a liquid crystal display unit and a static display unit.

[0033] The beneficial effect of adopting the above further solution is: making the system compatible with a variety of light control structures and display units, thereby improving the applicability of the system.

[0034] Furthermore, the edge-entry backlight structure provides light sources to the optical waveguide structure from both sides facing the optical waveguide structure at the same time; the other two sides of the optical waveguide structure are plated with reflective film layers.

[0035] The beneficial effects of adopting the above further solution are: improving energy utilization and light uniformity. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1This is the structural diagram of the system;

[0037] Figure 2 It is a traditional three-dimensional display schematic;

[0038] Figure 3 is a schematic diagram of the optical waveguide structure;

[0039] Figure 4 This is the light control schematic diagram of this system;

[0040] Figure 5 Construct a schematic diagram for a single viewpoint;

[0041] Figure 6 This is a schematic diagram of multi-viewpoint light control;

[0042] Figure 7 A schematic diagram of a three-dimensional display with balanced angular resolution;

[0043] Figure 8 A schematic diagram of a three-dimensional display with uneven angular resolution;

[0044] Fig. 9 A schematic diagram for improving the display depth of a three-dimensional display system.

[0045] Among them: 1. optical waveguide structure; 2. light control structure; 3. coupling unit; 4. display unit. DETAILED DESCRIPTION

[0046] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0047] like Figure 1 , Figure 2 and Figure 3 As shown, the flexible light-control 3D display system based on optical waveguide includes an edge-entry backlight structure, an optical waveguide structure 1, a light-control structure 2 and a display unit 4; a plurality of coupling units 3 are arranged on the optical waveguide structure 1; the light-control structure 2 includes a plurality of light-control units; wherein:

[0048] The side-entry backlight structure is used to provide a light source for the optical waveguide structure 1 from the side;

[0049] An optical waveguide structure 1, used for reflecting light entering therein and allowing part of the light to escape from the coupling unit 3;

[0050] The coupling unit 3 is used to make the light entering therein escape from different angles and directions in a scattered and reflected manner; all the coupling units 3 form a dot matrix light source array;

[0051] A light control unit, located between the coupling unit 3 and the display unit 4, is used to control the light by deflecting the light escaping from the coupling unit 3, so that the light passing through the light control unit projects each sub-pixel on the display unit 4 into a body pixel, thereby realizing three-dimensional display;

[0052] Display unit 4, used to provide display information;

[0053] The light is flexibly controlled by controlling the relative position relationship between the coupling unit 3 and the light control unit.

[0054] In this embodiment, since the system places the light control structure 2 on the inner side of the display unit 4, and each light control unit can be made very small, so that the size of each light control unit can be less than or equal to the size of a pixel on the display unit 4, such a special structure allows us to achieve flexible light control in three-dimensional display, which is of great significance for improving the various performances of three-dimensional light field display. This example uses a double-sided side-entry backlight structure, an optical coupling hole is set on the optical waveguide structure 1 as a coupling unit 3, a cylindrical lens is used as a light control unit, and an LCD display panel is used as a display unit 4. However, it should be noted that the light control unit can also be a slit grating, a dot lens, a microhole, an ordinary lens or a composite lens, and different light control units in the same light control structure 2 can also adopt different structures. In addition to the liquid crystal display unit 4 represented by the LCD display panel, the display unit 4 can also adopt other static displays.

[0055] In the specific implementation process, two opposite LED light strips are used as the side-entry backlight structure, and the other two sides are coated with reflective film layers to improve energy utilization and lighting uniformity. Tiny frosted holes are made on the side of the optical waveguide structure 1 facing the LCD display surface as optical coupling units 3, namely optical coupling holes. When the light beam is irradiated to the optical coupling hole, due to the irregular structure of the optical coupling hole, the light beam will be scattered and reflected at different angles and directions. Compared with glass with a smooth surface, the optical coupling hole can scatter the light beam more effectively, thereby realizing the coupling of the optical waveguide structure 1 with the external structure. If a process such as laser direct writing is used, the size of the coupling holes on the optical waveguide can be controlled at the micron level. The optical coupling holes on these optical waveguide structures 1 can be used as a dot matrix light source array, and the size of each light source can be controlled to be very small.

[0056] Although the optical waveguide structure 1 can provide a very small surface light source, it is not possible to achieve a flexible light control effect by relying solely on the optical waveguide structure 1. To achieve a flexible light control effect, a light control structure 2 needs to be added. In this embodiment, a cylindrical lens grating is used as the light control structure 2. The cylindrical lens aperture is theoretically not less than the optical coupling hole size. The cylindrical lens grating is precisely attached to the optical waveguide structure 1 to achieve joint light control. The modulated light is used as the backlight of the LCD display panel, thereby achieving independent light control at the sub-pixel level. The specific structure is as follows: Figure 4 As shown in the figure, q is the diameter of a pixel on the LCD display panel, p is the diameter of the cylindrical lens, and r is the diameter of the optical coupling hole. Figure 4 The figure shows a schematic diagram of light control for a single viewpoint. Only the optical coupling hole that provides light for the same viewpoint is drawn on the optical waveguide structure 1. If the three-dimensional display system requires n viewpoints, then p = nr. Since the optical coupling hole is located near the focal plane of the cylindrical lens grating, the light emitted from an optical coupling hole and obtained by passing through a cylindrical lens unit can be regarded as a beam of parallel light. Therefore, the width of the light control area formed on the LCD display panel is equal to the diameter of the cylindrical lens, both of which are p. Therefore, to achieve flexible light control, r must be satisfied. <p,p≤q。

[0057] In a possible scenario, the period of the light coupling hole corresponding to the same viewpoint is different from the period of the light control unit, and the period of the light coupling hole is slightly larger than the period of the light control unit. Figure 5 The optical waveguide structure 1 is an optical coupling hole that provides light for the same viewpoint. According to the geometric relationship in the figure, the relationship between the period D of the light control unit corresponding to the same viewpoint and the period d of the optical coupling hole, the viewing distance L, and the distance l between the light control unit and the coupling unit 3 can be obtained, that is, At this time, a parallax image corresponding to a viewpoint is filled in the display unit 4, so that the correct display content can be viewed at the viewpoint.

[0058] In a possible scenario, three-dimensional display often has multiple viewpoints, so there is more than one positional relationship between the light control unit and the coupling unit 3. The schematic diagram of multi-viewpoint light control is as follows: Figure 6 As shown, the optical coupling hole is located near the focal plane of the cylindrical lens grating, and the light emitted by each optical coupling hole is deflected by the cylindrical lens and becomes a beam of parallel light, and the spot diameter is equal to the diameter of the cylindrical lens. At this time, one pixel on the display unit 4 corresponds to at least one light control unit (cylindrical lens), so the structure can control the direction of the light by adjusting the relative position of the optical coupling hole and the light control unit, thereby achieving a flexible light control effect. At the same time, if there are optical coupling holes corresponding to multiple viewpoints under a light control unit, if the distance between the centers of any two viewpoints is m, the viewing distance is L, the distance between the light control unit and the coupling unit 3 is l, and the minimum spacing between the optical coupling holes corresponding to the two viewpoints is n, then according to similar triangles, it can be concluded that Right now

[0059] In the specific implementation process, the system can be used to flexibly control the angular resolution of three-dimensional display, enhance the display depth of three-dimensional display, etc. Figure 7 and Figure 8 These are two examples of controlling angular resolution. The two examples are respectively provided with five viewpoints, each viewpoint corresponds to three pixels on the display panel, and each pixel on the display unit 4 is independently light-controlled. By adjusting the relative position relationship between the light-control unit and the coupling unit 3, the angular resolution can be flexibly controlled. Figure 7 It is an example of a 3D display system with balanced angular resolution, which corresponds to the uniform distribution of viewpoints in traditional 3D light field display, and enables people to see a relatively continuous 3D display effect; Figure 8 is an example of a 3D display system with uneven angular resolution. By changing the relative position relationship between the light control unit and the coupling unit 3, the distance between viewpoint 2 and viewpoint 3 can be made smaller than the distance between viewpoint 1 and viewpoint 2, that is, the angular resolution of the middle view area is greater than that of the edge view area. In these two examples, there is only one coupling unit 3 corresponding to one viewpoint under one light control unit. If the distance between the centers of two adjacent viewpoints is m * , the viewing distance is L, the distance between the light control unit and the coupling unit 3 is l, the aperture of the light control unit is p, and the minimum spacing of the light coupling holes corresponding to these two viewpoints is n * , then In practical applications, based on people's viewing habits, the angular resolution in the center of the viewing range can be increased, while the angular resolution at the edge can be reduced, thereby making full use of the display information and improving the three-dimensional display effect.

[0060] Fig. 9 This is an example of improving the display depth of a 3D display system. In traditional 3D displays, since each cylindrical lens covers multiple sub-pixels, the display information in the horizontal direction can be fully utilized, while the display information in the vertical direction cannot be fully utilized, which limits the display depth of the 3D display system to a certain extent, affecting the 3D display effect. This system can achieve flexible light control, so it can flexibly control the display information in the horizontal and vertical directions to design the viewpoint, so that the display information in the vertical direction can be fully utilized in the horizontal direction, thereby improving the display depth of the 3D display system. Fig. 9 As shown, this example has nine viewpoints in total. After the sub-pixels on the display unit 4 are evenly distributed to the nine viewpoints, the angular resolution of the system is improved and the display depth is also improved.

[0061] The above examples are typical embodiments of the present invention and fall within the scope of protection of this patent. At the same time, the use of other side-entry backlight structures derived from the above examples, the use of other coupling units to emit light, the use of slit gratings, cylindrical lens gratings, dot lens arrays, micro-hole arrays, lens arrays and their combinations as light control structures, and the use of other display units to provide display information, thereby realizing a flexible light-controlled three-dimensional display system solution, and the use of flexible light-control structures to control the three-dimensional display angular resolution and improve the display depth of the three-dimensional display system solution, should all fall within the scope of protection of this patent.

Claims

1. A flexible light-control 3D display system based on optical waveguide, characterized in that: It includes an edge-type backlight structure, an optical waveguide structure, a light control structure and a display unit; a plurality of coupling units are arranged on the optical waveguide structure; the light control structure includes a plurality of light control units; wherein: The side-entry backlight structure is used to provide a light source for the optical waveguide structure from the side; An optical waveguide structure, used for reflecting light entering therein and allowing part of the light to escape from the coupling unit; A coupling unit, used to make the light entering it escape from different angles and directions in a scattered and reflected manner; all coupling units form a dot matrix light source array; A light control unit, located between the coupling unit and the display unit, is used to control the light by deflecting the light escaping from the coupling unit, so that the light passing through the light control unit projects each sub-pixel on the display unit into a body pixel, thereby realizing three-dimensional display; A display unit, used for providing display information; The light is flexibly controlled by controlling the relative position relationship between the coupling unit and the light control unit.

2. The flexible light-control 3D display system based on optical waveguide according to claim 1, characterized in that: The size of each light control unit is less than or equal to the size of a pixel.

3. The flexible light-control 3D display system based on optical waveguide according to claim 1, characterized in that: The size of a single coupling unit is less than or equal to one third of the size of the light control unit.

4. The flexible light-control 3D display system based on optical waveguide according to claim 1, characterized in that: The constraint relationship between the coupling unit and the light control unit corresponding to the same viewpoint is: Wherein d is the period of the coupling unit; D is the period of the light control unit; L is the viewing distance; and l is the distance between the light control unit and the coupling unit.

5. The flexible light-control 3D display system based on optical waveguide according to claim 1, characterized in that: When there are multiple coupling units corresponding to viewpoints under the same light control unit, the following constraints apply: Wherein m is the distance between the centers of any two viewpoints; n is the minimum spacing between the coupling units corresponding to the two viewpoints; L is the viewing distance; and l is the distance between the light control unit and the coupling unit.

6. The flexible light-control 3D display system based on optical waveguide according to claim 1, characterized in that: When there is only one coupling unit corresponding to one viewpoint under the same light control unit, the following constraints apply: Where m * is the distance between the centers of two adjacent viewpoints; n * is the minimum spacing between the coupling units corresponding to the two viewpoints; p is the aperture of the light control unit; L is the viewing distance; l is the distance between the light control unit and the coupling unit.

7. The flexible light-control 3D display system based on optical waveguide according to any one of claims 1 to 6, characterized in that: The coupling unit is an optical coupling hole, and the inner wall of the optical coupling hole is frosted.

8. The flexible light-control 3D display system based on optical waveguide according to any one of claims 1 to 6, characterized in that: The light control unit includes a slit grating, a cylindrical lens, a dot lens, a micro-hole, a common lens and / or a compound lens.

9. The flexible light-control 3D display system based on optical waveguide according to any one of claims 1 to 6, characterized in that: The display unit includes a liquid crystal display unit and a static display unit.

10. The flexible light-control 3D display system based on optical waveguide according to any one of claims 1 to 6, characterized in that: The side-entry backlight structure provides light sources to the optical waveguide structure from both sides facing the optical waveguide structure at the same time; the other two sides of the optical waveguide structure are coated with reflective film layers.

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