CN112269271B - Naked eye three-dimensional display device - Google Patents

Abstract

The invention provides a naked eye three-dimensional display device, which comprises: a display section including a display cell array in which a plurality of display cell arrays are arranged; and the visual angle regulation and control device comprises a visual angle regulation and control unit array formed by arranging a plurality of visual angle regulation and control unit arrays, wherein each visual angle regulation and control unit corresponds to a plurality of display units, the display units are divided into a plurality of groups, light rays emitted by each group of display units are converged into one visual angle through the visual angle regulation and control device, light rays emitted by different groups of display units are converged into different visual angles through the visual angle regulation and control device, each display unit in each group of display units corresponds to different visual angle regulation and control units, and the plurality of display units corresponding to each visual angle regulation and control unit are divided into different groups. In this way, different three-dimensional display effects viewed at different viewing angles can be achieved, and a full parallax image can be reproduced.

Description

Naked eye three-dimensional display device

Technical Field

The invention relates to the technical field of three-dimensional display, in particular to a naked eye three-dimensional display device.

Background

As one of the main sources of information acquired by human, vision is very important in daily life. Unlike natural scenes, conventional display devices can only present two-dimensional images at present. This lack of depth-based flat information limits human exploration and cognition in the world to some extent. Studies have shown that almost 50% of the human brain is used to participate in the processing of visual information, and the presentation of two-dimensional images results in a reduction in brain utilization. The naked eye 3D (3D) display has great application value in movie and television, games, education, vehicle-mounted, aviation, medical treatment and military. Taking the military field as an example, the visualization of a 3D image is required in each link of machine manufacturing, battlefield analysis, military command, remote operation, and the like, and the improvement of the working efficiency will be greatly influenced. Therefore, 3D display is known as "next generation display technology", and is one of the techniques in which important research fields and many display companies are controversial.

Based on the mechanism and method for realizing naked eye 3D display of parallax barrier, cylindrical lens array, space-time multiplexing or integrated optical field, etc., the optical element with periodic microstructure or nano structure is used to regulate and control the phase of the display optical field and project the image information of different visual angles to different visual angles in the mode of approximate parallel light beams. Although the autostereoscopic display technology has made great progress, the naked-eye 3D display technology has not yet succeeded in entering the field of flat panel display. The display problems of dizziness (convergence adjustment contradiction), image crosstalk/ghost, resolution reduction and the like, and the device structure problems of ultra-thinning, light utilization rate and the like need to be solved urgently.

Therefore, there is a need for an improved solution to overcome the above problems.

Disclosure of Invention

The invention aims to provide a naked eye three-dimensional display device which can realize different three-dimensional display effects observed under different visual angles and can reproduce full parallax images.

To achieve the object, according to one aspect of the present invention, there is provided a naked eye three-dimensional display device including: a display section including a display cell array in which a plurality of display cell arrays are arranged; and the visual angle regulation and control device comprises a visual angle regulation and control unit array formed by arranging a plurality of visual angle regulation and control unit arrays, wherein each visual angle regulation and control unit corresponds to a plurality of display units, the display units are divided into a plurality of groups, light rays emitted by each group of display units are converged into one visual angle through the visual angle regulation and control device, light rays emitted by different groups of display units are converged into different visual angles through the visual angle regulation and control device, each display unit in each group of display units corresponds to different visual angle regulation and control units, and the plurality of display units corresponding to each visual angle regulation and control unit are divided into different groups.

Compared with the prior art, the invention adopts the micro-lens array as the visual angle regulating device, can realize different three-dimensional display effects observed under different visual angles, and can reproduce full parallax images.

Drawings

Fig. 1 is a schematic diagram of a basic principle for reproducing a full parallax image using a two-dimensional microlens array;

FIG. 2 is a schematic diagram of two implementations for rendering a full parallax image using a two-dimensional microlens array;

FIG. 3 is a schematic structural diagram of a naked eye three-dimensional display device in a first embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a naked eye three-dimensional display device in a second embodiment of the present invention;

FIG. 5 is a schematic diagram of a view angle adjusting device according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a lens collapse design of the present invention;

FIG. 7 is a schematic view of a view angle adjusting device according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of principle analysis of a naked eye three-dimensional display device according to the present invention;

FIG. 9 is a schematic structural diagram of a naked eye three-dimensional display device in a third embodiment of the present invention;

FIG. 10 is a schematic top view and a schematic cross-sectional view of the aperture array stop of FIG. 9 in one embodiment;

FIG. 11 is a schematic diagram illustrating the light propagation effect of the apertures in the aperture array diaphragm of FIG. 10;

FIG. 12 is a schematic diagram of two arrangements of the microlens array of the present invention, wherein the aperture of each microlens is the same;

FIG. 13 is a schematic view of three other arrangements of the microlens array of the present invention, wherein the aperture of each microlens is not completely uniform; and

fig. 14 is a schematic diagram showing a comparison between the information density arrangement of a single aperture microlens and the information density arrangement of a multi-aperture composite structure.

Detailed Description

To further explain the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description of the embodiments, structures, features and effects according to the present invention will be given with reference to the accompanying drawings and preferred embodiments.

The principle of the two-dimensional microlens array capable of reproducing a full parallax image is shown in fig. 1, when an image is recorded, images with different viewing angles generated by each microlens unit correspondingly are recorded, when the image is reproduced, emergent rays of multi-viewing-angle image elements are reproduced in front of the microlens array, thousands of viewing angles are reconstructed on a two-dimensional space by the method of the microlens array, full parallax can be achieved, namely, parallax in the horizontal and vertical directions exists, a complete 3D image is formed, and motion parallax information can be provided.

In describing the microlens array topography, the equation can be introduced:

where C is the curvature (curvature) at the apex of the lens, K is the conic constant (conic constant), R is the distance from a point on the lens surface to the center of the lens, a_kAre high order aspheric coefficients. When a is_kAt zero, the conic constant K determines the surface of the liquid lens. When in useK<At-1, it is hyperbolic; when K = -1, is parabolic; when-1<K<At 0, it is an ellipse; circle when K = 0; when K is>At 0, it is an ellipse. For aspheric surfaces, the conic constant plays a very important role in the quality of the lens image, and the magnitude of the conic constant affects the geometric aberrations of the lens, and therefore, the conic constant is controlled when designing an aspheric lens.

In the existing method for realizing naked eye 3D display by utilizing a micro-lens array, structural morphology parameters (curvature and rise) are periodically changed along with position parameters (x y) and are not independent variables. And therefore does not meet the light field reconstruction requirements and cannot reconstruct a 3D light field. The specific expression is that the problems of poor display effect, serious resolution reduction, limited field angle and the like are not well solved.

As shown in the left diagram of fig. 2, there is also a problem of limited viewing angle, mainly because at a large viewing angle, the image corresponding to a single microlens exceeds the image area at the present viewing angle. One solution is to use a curved display screen, as shown in the right diagram of fig. 2, to change the optical axis positions of the edge lenticules and the display screen (which includes a plurality of display cells). And enabling the visual angle image corresponding to the edge micro lens to be always positioned in the center of the display unit corresponding to the visual angle. However, the method changes the traditional display screen form, does not conform to the flat panel display observation habit, and is inconvenient to carry.

Fig. 3 is a schematic structural diagram of a naked eye three-dimensional display device in a first embodiment 300 of the invention. As shown in fig. 3, the naked eye three-dimensional display apparatus includes a display part 310 and a viewing angle adjusting device 320.

The display component 310 may also be referred to as a display screen. The display component can be an OLED screen, a miniLED screen, an OLED screen or a micro LED screen, and can also be an LCD display screen and the like. Preferably, the display component 310 is a micro light emitting diode (micro led) display screen, each of the light emitting diodes has a length and a width of 100 micrometers or less, and each of the light emitting diodes can be driven to light individually. Due to the adoption of the micro led screen, the resolution of the display part 310 can be greatly improved, thereby improving the resolution of the final 3D display image. The display part 310 includes a display unit array formed by arranging a plurality of display unit arrays, and the plurality of display units form a display assembly 311. Only five display elements 311 are shown in fig. 3, and in practice, the number of display elements 311 may be large. Each display assembly 311 includes a plurality of display pixels or display units arranged in an array, for example, each display unit may be an LED unit. The display cell array is configured to simultaneously display a plurality of images having different viewing angles.

The viewing angle adjusting device 320 includes a viewing angle adjusting unit array formed by arranging a plurality of viewing angle adjusting units 321 in an array, wherein each viewing angle adjusting unit 321 corresponds to one display module 311. The display units are divided into a plurality of groups, light rays emitted by each group of display units are converged into one visual angle through the visual angle regulating device 320, light rays emitted by different groups of display units are converged into different visual angles through the visual angle regulating device, each display unit in each group of display units corresponds to a different visual angle regulating unit 321, and a plurality of display units corresponding to each visual angle regulating unit 321 are divided into different groups.

In one embodiment, the display unit includes at least one of a red led, a blue led and a green led, and light emitted from the red led, the blue led and the green led passes through the same viewing angle adjusting unit 321.

As shown in fig. 3, a side of the viewing angle regulating unit array away from the display part 310 is a microlens array 330 composed of microlens units 331, and a side of the viewing angle regulating unit array close to the display part 310 is a dioptric lens 340. In this embodiment, the diopter lens 340 is a convex lens. The microlens unit 331 is used to image the image displayed by the display unit 311 to a corresponding viewing angle, and the dioptric lens 340 is used to enlarge a viewing angle, so that the display part 310 does not need to be provided in a curved shape as in fig. 2. As shown in fig. 3, the convex lens is relatively thick, which is disadvantageous for reducing the thickness of the device. Of course, in another embodiment, the microlens array 330 may be disposed on a side close to the display part 310, and the diopter lens 340 may be disposed on a side far from the display part 310.

Fig. 6 is a schematic diagram of the lens collapse design of the present invention. As shown in fig. 6, the original large convex lens collapse results in the following process: the height of collapse can be 2 pi or an integer P times 2 pi, as shown in FIG. 6, the single-layer structure formed by collapse has a very thin thickness, and the structural morphology can be processed by a photoetching device. It is to be understood that the optical effect of the single-layer structure formed by collapse is similar to that of the large convex lens before collapse. The diopter lens 340 of fig. 3 may also be designed to collapse to reduce the thickness of the diopter lens 340 according to the principles illustrated in fig. 6.

Fig. 4 is a schematic structural diagram of a naked eye three-dimensional display device in a second embodiment 400 of the invention. The naked-eye three-dimensional display apparatus 400 of fig. 4 includes a display part 410 and a viewing angle adjusting device 420, and the viewing angle adjusting device 420 includes a micro lens array 430 and a dioptric lens 440, which are substantially the same as the naked-eye three-dimensional display apparatus 300 of fig. 3. The difference between the two is that: the dioptric lens 400 of fig. 4 is a harmonic diffractive lens, while the dioptric lens 440 of fig. 3 is a normal convex lens, and further, the harmonic diffractive lens of fig. 4 is integrated with the microlens array 430 to form a composite view angle adjusting device, while the dioptric lens 340 of fig. 3 is assembled on one side of the microlens array 330. The surface of one side of the composite view angle adjusting device 420 is a micro lens array 430, and the other side is a harmonic diffraction lens. At this time, each of the viewing angle adjusting units includes a microlens unit 431 located at a side far from the display part and a harmonic diffraction lens unit located at a side near to the display part 410, wherein the harmonic diffraction lens units of the plurality of viewing angle adjusting units constitute a complete harmonic diffraction lens. In another embodiment, the diopter lens 440 may also be a Fresnel lens. The harmonic diffractive lens of fig. 4 can be obtained by collapsing the convex lens 340 of fig. 3 according to the lens collapse design principle.

The arched microlens array can obtain a larger field angle, however, the arched structure is inconvenient to process, and the convex microlens array is difficult to align with the display screen. Similarly, the method of lens collapse design shown in FIG. 6 can also be used to form a thin structure by collapsing the arched microlens array. Fig. 5 is a schematic diagram of a view angle adjusting device according to an embodiment of the present invention. As shown in fig. 5, the collapsed shape of the microlens array can be regarded as being formed by a plurality of fresnel lens arrays, that is, each microlens unit adopts a fresnel lens structure, and the microlens array 530 and the harmonic diffraction lens 540 are overlapped to form the composite optical lens 520, so as to obtain a larger field angle, and the viewing angle adjusting device becomes very light and thin. It should be noted that, unlike the form of fig. 4 in which the microlens array is formed on one side of the lens and the harmonic diffraction lens is formed on the other side of the lens, the composite optical lens in fig. 5 is directly manufactured by superimposing the phases of the harmonic diffraction lens and the microlens array in advance. The single-layer thin-film device with the composite optical characteristic of the micro-lens array and the convex lens can be realized through phase superposition, as shown in fig. 5, so that the processing process steps are simplified, the thickness of the device is reduced, and the observation field angle of 3D display is improved. Of course, the harmonic diffractive lens 540 in fig. 5 may also adopt a fresnel lens, i.e., a microlens array + fresnel lens to form a composite optical lens. Further, each microlens unit may also employ a harmonic diffractive lens structure.

Fig. 7 is a schematic diagram of the fabrication of the viewing angle adjusting device 420 in fig. 4 in one embodiment. As shown in fig. 7, the view angle adjusting device 420 has a double-sided structure, and at this time, the two sides of the substrate can be respectively stamped by using the dies 1 and 2 carved in advance, the micro-lens array structure is stamped and formed on one surface of the substrate by using the die 1, and the harmonic diffraction lens is formed by extending on the other surface of the substrate by using the die 2. Of course, other methods can be used to fabricate the viewing angle adjusting device.

Fig. 8 is a schematic diagram illustrating principle analysis of a naked eye three-dimensional display device according to the present invention. As shown in fig. 8, a total of five viewing angle adjusting units 321-1 to 321-5 and five display elements 311-1 to 311-5 are shown, and the number is merely an example, and it is obvious that other numbers are possible. Each of the angle-of-view adjusting units 321 includes a microlens unit 331 and one diopter lens unit 341 of the diopter lenses 340. The display units are divided into a plurality of groups, light rays emitted by each group of display units are converged into one visual angle through the visual angle regulating devices 321-1 to 321-5, and light rays emitted by different groups of display units are converged into different visual angles theta 1 to theta 5 through the visual angle regulating devices. Each display unit (corresponding to a certain visual angle) in each group of display units corresponds to different visual angle regulating units, a plurality of display units corresponding to each visual angle regulating unit are divided into different groups, and light rays emitted by the display components corresponding to each visual angle regulating unit are scattered and emitted to different visual angles by the visual angle regulating units due to different incidence directions. At the viewing angle θ 1, light emitted from each display unit distributed in different display modules can be seen, so that an image of one viewing angle can be seen. Similarly, at other viewing angles, the light emitted from each display unit distributed in different display assemblies can be seen, so that the images at other viewing angles can be seen.

Thus, when a user watches the display component at a first position, one eye of the user is positioned at a first visual angle and can see the light rays emitted by the first group of display units through the corresponding different visual angle regulating units, and the other eye is positioned at a second visual angle and can see the light rays emitted by the second group of display units through the corresponding different visual angle regulating units, for example, when the user is positioned at the first position in fig. 8, one eye is positioned at a visual angle θ 1, and the other eye is positioned at a visual angle θ 2, so that the user can see images of two different visual angles with a visual angle difference at the first position to form a first three-dimensional image in the brain of the user. When a user watches the display component at the second position, one eye of the user is located at the third viewing angle and can see the light emitted by the third group of display units through the corresponding different viewing angle regulating units, and the other eye is located at the fourth viewing angle and can see the light emitted by the fourth group of display units through the corresponding different viewing angle regulating units, for example, when the user is located at the second position in fig. 8, one eye is located at the viewing angle θ 3 and the other eye is located at the viewing angle θ 4, so that the user can see two other images with different viewing angles at the second position to form a second three-dimensional image, wherein the viewing angles of the first three-dimensional image and the second three-dimensional image are different.

Fig. 9 is a schematic structural diagram of a naked eye three-dimensional display device in a third embodiment 900 of the invention. As shown in fig. 9, the naked eye three-dimensional display device 900 also includes a display unit 910 and a viewing angle adjusting device 920. The naked-eye three-dimensional display device in fig. 9 is different from the naked-eye three-dimensional display device in fig. 4 in that: the naked eye three-dimensional display device 900 of fig. 9 also includes light collimating components. In the example shown in fig. 9, the light collimating component is an aperture array stop 950 that collimates the outgoing light rays of the display component 910. As shown in fig. 10 and 11, the aperture array stop 950 includes apertures 951 arranged in an array, each aperture may correspond to one display pixel (e.g., one light emitting diode), and light emitted from one display pixel is transmitted to a corresponding viewing angle adjusting unit through the corresponding aperture 951.

The shape of aperture 951 may be square, circular, polygonal, but circular is preferred in view of the symmetry of the light rays. The aperture 951 may be a circular column, as shown in fig. 11 (a), or a trapezoidal column, as shown in fig. 11 (b), in which case the diameter of the side of the aperture 951 facing the display pixels of the display unit is smaller than the diameter of the side of the aperture facing the viewing angle adjusting unit.

In addition, the naked eye three-dimensional display device can further comprise a shielding device. The shielding means may be a separate device located above or below the viewing angle adjusting device, or integrated (embedded) on the viewing angle adjusting device. Alternatively, the blocking device may be integrated with the aperture stop, corresponding to an array aperture stop of the integrated blocking device.

In one embodiment, the display assembly provides individual view angle images, each view angle image is composed of a plurality of display pixels of a corresponding display unit, each display pixel is composed of R, G, B three colors, light emitted by the display assembly is first collimated by an aperture array diaphragm, and R, G, B of each display pixel corresponds to an aperture of the aperture array diaphragm one to one. And the light collimated by the aperture array diaphragm passes through the visual angle regulating device to be turned to a preset position.

Fig. 12 is a schematic diagram of two arrangement modes of the microlens array in the present invention, wherein each microlens unit in the left drawing of fig. 12 is circular, there is a gap between the microlens units, each microlens unit in the right drawing of fig. 12 is hexagonal, there is no gap between the microlens units, and the microlens units are arranged in a honeycomb shape, so that the resolution can be improved. The aperture of the microlens unit is uniform in both arrangements in fig. 12. In addition, the microlens unit may have other shapes such as a rectangle, an octagon, a prism, and the like.

FIG. 13 is a schematic diagram of another three arrangements of the microlens array of the present invention. As shown in fig. 13, the microlens array includes microlens units with large size (or called aperture size) arranged in an array and microlens units with small size (or called aperture size) arranged in an array, the microlens units with large size are arranged in an array with a gap therebetween, and the microlens units with small size are disposed in the gap of the microlens unit array with large size. In fig. 13, the apertures of the microlens units are not uniform, some are large, some are small, the shape of the small-aperture microlens unit is one of circular, rectangular, octagonal, hexagonal and prismatic, and the shape of the large-aperture microlens unit is one of circular, rectangular, octagonal, hexagonal and prismatic. This may improve the resolution to some extent.

More importantly, the collection and presentation of 3D scene information in different viewing angle ranges can be realized by combining the micro-lens arrays with different apertures, so that three-dimensional display effects with different information densities can be obtained, as shown in the figure. The display method with high central information density and low edge information density is similar to the arrangement of human retina with high photoreceptor cell density in the central foveal area and low photoreceptor cell density in the edge area. Under the condition of limited information quantity, more information is put at a central visual angle, so that the human eye observation habit is met. Fig. 14 is a schematic diagram illustrating comparison between information density arrangement of a single-aperture microlens and information density arrangement of a multi-aperture composite structure, in which three arrangements shown in fig. 13 are multi-aperture composite structures, and two arrangements shown in fig. 12 are single-aperture microlenses.

As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, including not only those elements listed, but also other elements not expressly listed.

In this document, the terms front, back, upper and lower are used to define the components in the drawings and the positions of the components relative to each other, and are used for clarity and convenience of the technical solution. It is to be understood that the use of the directional terms should not be taken to limit the scope of the claims.

The features of the embodiments and embodiments described herein above may be combined with each other without conflict.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (10)

1. A naked eye three dimensional display device, comprising:

a display section including a display cell array in which a plurality of display cells are arranged; and

a visual angle regulating device, which comprises a visual angle regulating unit array formed by arranging a plurality of visual angle regulating unit arrays, wherein each visual angle regulating unit corresponds to a plurality of display units, the display units are divided into a plurality of groups, light rays emitted by each group of display units are converged into one visual angle through the visual angle regulating device, light rays emitted by different groups of display units are converged into different visual angles through the visual angle regulating device, each display unit in each group of display units corresponds to a different visual angle regulating unit, the plurality of display units corresponding to each visual angle regulating unit are divided into different groups,

the visual angle regulating device comprises a micro lens array formed by arranging a micro lens unit array and a dioptric lens for enlarging the visual angle, wherein the micro lens unit array is arranged in a plurality of rows and a plurality of columns, the micro lens array and the dioptric lens are in an integrated structure, or the micro lens array is assembled at one side of the dioptric lens,

the display cell array is configured to simultaneously display a plurality of images having different viewing angles.

2. The naked eye three dimensional display device of claim 1, further comprising:

a light collimating component between the display component and the viewing angle adjusting device, the light collimating component configured to collimate and bundle light emitted by the display unit in a direction.

3. The naked eye three-dimensional display device of claim 2, wherein the light collimating component comprises an aperture array diaphragm, the aperture array diaphragm comprises apertures arranged in an array, each aperture corresponds to one light emitting diode, and light emitted by one light emitting diode is transmitted to the corresponding viewing angle regulating unit through the corresponding aperture.

4. The naked eye three-dimensional display device of claim 3, wherein a diameter of a side of the aperture facing the light emitting diode is smaller than a diameter of a side of the aperture facing the viewing angle adjusting unit.

5. The naked eye three dimensional display apparatus of claim 1,

the dioptric lens is a harmonic diffraction lens or a Fresnel lens.

6. The naked eye three dimensional display apparatus of claim 5,

each microlens unit employs a harmonic diffractive lens structure or a fresnel lens structure.

7. The naked eye three dimensional display apparatus of claim 1,

each microlens unit is one or more of circular, rectangular, octagonal, hexagonal and prismatic; or

The size of part of the microlens units is large, the size of part of the microlens units is small, the large-size microlens units are arranged into an array and have gaps, the small-size microlens units are arranged in the gaps of the large-size microlens unit array,

the small-sized microlens unit is one of a circle, a rectangle, an octagon, a hexagon and a prism,

the shape of the large-size microlens unit is one of circular, rectangular, octagonal, hexagonal and prismatic.

8. The naked eye three dimensional display apparatus of claim 1,

the display component is an OLED screen, a miniLED screen or a microLED screen, and the display unit comprises one or more light-emitting diodes; or

The display component is a micro light-emitting diode display screen, the length and the width of each light-emitting diode are both less than or equal to 100 micrometers, and each light-emitting diode can be independently driven to light.

9. The naked eye three dimensional display device of claim 1, wherein the display unit comprises at least one of a red light emitting diode, a blue light emitting diode, and a green light emitting diode,

and light rays emitted by the red light-emitting diode, the blue light-emitting diode and the green light-emitting diode pass through the same visual angle regulating and controlling unit and then form an image.

10. The naked eye three dimensional display apparatus of claim 1,

when a user watches the display part at a first position, one eye of the user is positioned at a first visual angle and can see the light rays emitted by the first group of display units through the corresponding different visual angle regulation units, and the other eye of the user is positioned at a second visual angle and can see the light rays emitted by the second group of display units through the corresponding different visual angle regulation units, so that the user can see images with two different visual angles having a visual angle difference at the first position to form a first three-dimensional image in the brain of the user;

when a user watches the display part at the second position, one eye of the user is positioned at the third visual angle and can see the light rays emitted by the third group of display units through the corresponding different visual angle regulating units, and the other eye is positioned at the fourth visual angle and can see the light rays emitted by the fourth group of display units through the corresponding different visual angle regulating units, so that the user can see other two images with different visual angles at the second position to form a second three-dimensional image, wherein the visual angles of the first three-dimensional image and the second three-dimensional image are different.

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