2d / 3d compatible augmented reality display device

Abstract

The application discloses a 2D / 3D compatible augmented reality display device, which comprises a projector, a polarization generation unit, a polarization selective holographic microlens array and an optical diffusion element. The projector projects a corresponding sheet source according to a display mode; the polarization generation unit is composed of a polarizer, a twisted nematic liquid crystal panel and a 1 / 4 wave plate. The polarizer performs polarization modulation on light; the twisted nematic liquid crystal panel is used for keeping linearly polarized light in the vertical direction or transforming it into linearly polarized light in the horizontal direction; the 1 / 4 wave plate transforms the passing linearly polarized light into circularly polarized light; the polarization selective holographic microlens array has focusing effect on right-handed circularly polarized light and defocusing effect on left-handed circularly polarized light. The optical diffusion element can homogenize 3D images, can be used as a screen for receiving 2D images and can also make ambient light directly pass through. The device can realize 2D augmented reality display, 3D augmented reality display and 2D / 3D compatible augmented reality display.

Description

I. TECHNICAL FIELD

[0001] The present application relates to the field of augmented reality technology, in particular to a 2D / 3D compatible augmented reality display device. II. BACKGROUND

[0002] Augmented reality technology is a technology that fuses virtual information with the real world, which can help observers focus more effectively on work, so it is widely studied by researchers and the industry. At the same time, with the development of augmented reality technology, people have not been satisfied with only displaying flat 2D images, and hope to observe more rich information, so 3D display has gradually been introduced into the field of augmented reality. Integrated imaging display technology can reconstruct the light field of a three-dimensional scene and provide full parallax, continuous view points and various physiological depth cues, and there is no problem of visual fatigue. At the same time, its structure is relatively compact, simple, and has small hardware complexity, which is suitable for integration into augmented reality displays. However, the current 2D / 3D compatible augmented reality display mostly uses time or spatial multiplexing technology, resulting in a large system size, complex structure, poor display image quality, and single type.

[0003] Although 3D display can provide depth information that 2D display does not have, current 3D display still has problems such as low image resolution, small viewing angle, narrow depth, and unsatisfactory display effect. 2D / 3D compatible display can display full-resolution 2D images in the background and 3D images with depth information in the foreground, optimizing the viewing experience of 3D images and promoting the application of 3D display, so it is necessary to develop 2D / 3D compatible display. Existing 2D / 3D compatible display schemes mostly use liquid crystal active devices to quickly switch display modes, based on the visual persistence effect of the human eye, to achieve 2D / 3D hybrid display; or use spatial division multiplexing technology to display 2D background images by back projection and 3D foreground images by front projection to form 2D / 3D hybrid display. This will result in complex system structure, reduced imaging quality, and inability to achieve virtual-real fusion effect. III. SUMMARY

[0004] The present application provides a 2D / 3D compatible augmented reality display device, as shown in the accompanying drawings, which comprises a projector, a polarization generation unit, a polarization-selective holographic microlens array and an optical diffusion element. Figure 1 The device has three modes of 2D display, 3D display and 2D / 3D compatible display, and can achieve virtual-real fusion effect.

[0005] The projector projects the corresponding film source according to the display mode, projects the 2D film source in the 2D display mode, projects the 3D film source in the 3D display mode, and projects the 2D / 3D hybrid film source in the 2D / 3D compatible display mode.

[0006] The polarization generation unit, composed of a polarizer, a twisted nematic liquid crystal panel, and a quarter-wave plate, is used to generate right-hand circularly polarized light, as shown in the attached figure. Figure 2 As shown, or left-handed circularly polarized light, as attached Figure 3 As shown. The polarizer is used to generate vertically linearly polarized light. The twisted nematic liquid crystal panel is used to maintain the vertically linearly polarized light or convert it into horizontally linearly polarized light. The quarter-wave plate is used to modulate the vertically and horizontally linearly polarized light into right-handed and left-handed circularly polarized light, respectively.

[0007] The polarization-selective holographic microlens array can achieve two states, state 1, as shown in the attached diagram. Figure 4 As shown, when the incident polarized light is right-handed circularly polarized, the polarization-selective holographic microlens array acts as a lens to focus the light; State 2, as shown in the attached diagram. Figure 5 As shown, when the incident polarized light is left-handed circularly polarized light, the polarization-selective holographic microlens array acts as a lens to defocus the light.

[0008] The optical diffusion element can both homogenize 3D images and serve as a screen for receiving 2D images. Furthermore, ambient light can also directly pass through the optical diffusion element and enter the human eye.

[0009] The optical path of the 2D / 3D compatible augmented reality display device in 2D augmented reality display mode is shown in the attached figure. Figure 6 As shown, the 2D source image projected by the projector generates left-handed circularly polarized light through the polarization generation unit. The polarization-selective holographic microlens array defocuses the left-handed circularly polarized light. The light diverged by the polarization-selective holographic microlens array is projected onto an optical diffusion element, which serves as a display screen to receive the 2D image, thus realizing the display of the 2D image. Simultaneously, ambient light can directly pass through the optical diffusion element and enter the viewer's eye. Therefore, the viewer in front of the display system can simultaneously see the 2D image and the real scene, achieving 2D augmented reality display.

[0010] The optical path of the 2D / 3D compatible augmented reality display device in 3D augmented reality display mode is shown in the attached figure. Figure 7 As shown, the 3D source material projected by the projector generates right-handed circularly polarized light through the polarization generation unit. The polarization-selective holographic microlens array acts as a lens to focus the right-handed circularly polarized light, converging the light and reconstructing a 3D image. The 3D image is then scattered by an optical diffusion element to form a continuous and smooth 3D image. Light from the real environment can directly pass through the optical diffusion element and enter the human eye, allowing the observer to see both the virtual 3D image and the real scene, thus achieving 3D augmented reality display.

[0011] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying Figure 8 The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying

[0012] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying IV. BRIEF DESCRIPTION OF DRAWINGS

[0013] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying Figure 1 The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying

[0014] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying Figure 2 The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying

[0015] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying Figure 3 The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying

[0016] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying Figure 4 The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying

[0017] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying Figure 5 The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying

[0018] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying Figure 6 The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanying

[0019] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in the accompanyingFigure 7 Light path schematic diagram of 3D augmented reality display mode of the device of the present application.

[0020] Figure Figure 8 Light path schematic diagram of 2D / 3D compatible augmented reality display mode of the device of the present application.

[0021] The figure numbers in the above figures are:

[0022] 1 projector, 2 polarizer, 3 twisted nematic liquid crystal, 4 1 / 4 wave plate, 5 polarization-selective holographic microlens array, 6 optical diffusion element, 7 polarization image generating unit, 8 vertically linearly polarized light, 9 horizontally linearly polarized light, 10 right circularly polarized light, 11 left circularly polarized light, 12 converging light rays, 13 diverging light rays, 14 2D image, 15 3D image, 16 real object, 17 viewer.

[0023] It should be understood that the above figures are only schematic and not drawn to scale. V. DETAILED DESCRIPTION

[0024] A typical embodiment of a 2D / 3D compatible augmented reality display device of the present application is described in detail below, and the present application is further described. It is necessary to point out here that the following embodiment is only used to further illustrate the present application, and cannot be understood as limiting the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application according to the above content of the present application, and still fall within the protection scope of the present application.

[0025] The present application proposes a 2D / 3D compatible augmented reality display device, as shown in Figure 1 The device is composed of a projector, a polarization generating unit, a polarization-selective holographic microlens array and an optical diffusion element. The device has three modes of 2D display, 3D display and 2D / 3D compatible display, and can all achieve the effect of virtual-real fusion.

[0026] The projector is a laser projector, and the projection resolution is 1920x1080 dpi. According to the display mode, the corresponding film source is projected. In the 2D display mode, a 2D film source is projected. In the 3D display mode, a 3D film source is projected. In the 2D / 3D compatible display mode, a 2D / 3D mixed film source is projected.

[0027] The polarization generating unit is composed of a polarizer, a twisted nematic liquid crystal panel and a 1 / 4 wave plate, and is used to generate right circularly polarized light, as shown in Figure 2 or left circularly polarized light, as shown in Figure 3The polarizer is used to generate linearly polarized light in the vertical direction. The twisted nematic liquid crystal panel is used to maintain linearly polarized light in the vertical direction or to transform it into linearly polarized light in the horizontal direction. The 1 / 4 wave plate is used to modulate the linearly polarized light in the vertical and horizontal directions into right-handed circularly polarized light and left-handed circularly polarized light, respectively.

[0028] The polarization-selective holographic microlens array can realize two states, state 1, as shown in FIG. 1, and state 2, as shown in FIG. 2. Figure 4 When the polarized light is right-handed circularly polarized light, the polarization-selective holographic microlens array has a lens focusing effect on the light, as shown in FIG. 1. Figure 5 When the polarized light is left-handed circularly polarized light, the polarization-selective holographic microlens array has a lens defocusing effect on the light, as shown in FIG. 2.

[0029] The light transmittance of the optical diffusion element is 88.0%, which can homogenize 3D images and also serve as a screen for 2D images. In addition, ambient light can directly pass through the optical diffusion element into the human eye.

[0030] The 2D / 3D compatible augmented reality display device, the light path in the 2D augmented reality display mode is as shown in FIG. 3. Figure 6 The 2D image source projected by the projector passes through the polarization generation unit to generate left-handed circularly polarized light. The polarization-selective holographic microlens array has a defocusing effect on the left-handed circularly polarized light. The light diverged by the polarization-selective holographic microlens array is projected on the optical diffusion element, which serves as a display screen for 2D images, realizing the display of 2D images. At the same time, the light of the real environment can directly pass through the optical diffusion element into the human eye, so that the viewer in front of the display system can see the 2D image and the real scene at the same time, realizing the augmented reality display of 2D.

[0031] The 2D / 3D compatible augmented reality display device, the light path in the 3D augmented reality display mode is as shown in FIG. 4. Figure 7 The 3D image source projected by the projector passes through the polarization generation unit to generate right-handed circularly polarized light. The polarization-selective holographic microlens array has a lens focusing effect on the right-handed circularly polarized light, and the light is converged to reconstruct a 3D image. The 3D image is scattered by the optical diffusion element to form a continuous and smooth 3D image. The light of the real environment can directly pass through the optical diffusion element into the human eye, so that the observer can see the virtual 3D image while also seeing the real scene, realizing the augmented reality display of 3D.

[0032] The 2D / 3D compatible augmented reality display device, the light path in the 2D / 3D compatible augmented reality display mode is as shown in FIG. 5. Figure 8As shown, the 2D / 3D mixed film source projected by the projector passes through the polarization generation unit, and left circularly polarized light 2D film source and right circularly polarized light 3D film source are generated respectively. The polarization selective holographic microlens array has a defocusing effect on the left circularly polarized light 2D film source, and the light diverged by the polarization selective holographic microlens array is projected on the optical diffusion element to realize the display of the 2D image. The polarization selective holographic microlens array has a focusing effect on the right circularly polarized 3D film source, and the light is converged to reconstruct the 3D image, which is then scattered by the optical diffusion element to form a continuous and smooth 3D image. The 2D image light and the 3D image light do not affect each other in space, thereby realizing 2D / 3D compatible display. At the same time, the light of the real environment can also directly pass through the optical diffusion element into the human eye, so that the observer can see the real scene while seeing the 2D / 3D mixed image, realizing 2D / 3D compatible augmented reality display.

[0033] The application provides a 2D / 3D compatible augmented reality display device, which generates circularly polarized light in different directions by a polarization generation unit, and modulates the polarized light in different directions by a polarization selective holographic microlens array, so that 2D augmented reality display, 3D augmented reality display and 2D / 3D compatible augmented reality display can be realized. The device can realize augmented reality effect in three display modes, and only one projector is needed to realize 2D / 3D compatible display, so that the structure is simple and the system is compact.

Claims

1. A 2D / 3D compatible augmented reality display device, characterized by, The device is composed of a projector, a polarization generation unit, a polarization-selective holographic microlens array and an optical diffusion element; the projector projects corresponding film sources according to display modes, projects 2D film sources in 2D display mode, projects 3D film sources in 3D display mode, and projects 2D / 3D mixed film sources in 2D / 3D compatible display mode; the polarization generation unit is composed of a polarizer, a twisted nematic liquid crystal panel and a 1 / 4 wave plate, and is used for generating right circularly polarized light or left circularly polarized light; the polarizer is used for generating vertically linearly polarized light; the twisted nematic liquid crystal panel is used for keeping the vertically linearly polarized light or transforming it into horizontally linearly polarized light; the 1 / 4 wave plate is used for modulating the vertically and horizontally linearly polarized light into right circularly polarized light and left circularly polarized light respectively; the polarization-selective holographic microlens array can realize two states, state 1, when the incident polarized light is right circularly polarized light, the polarization-selective holographic microlens array has a focusing effect of a lens on the light; state 2, when the incident polarized light is left circularly polarized light, the polarization-selective holographic microlens array has a defocusing effect of a lens on the light; the optical diffusion element can homogenize 3D images and also can be used as a screen for receiving 2D images, and ambient light can directly pass through the optical diffusion element into the human eye.

2. The 2D / 3D compatible augmented reality display device of claim 1, wherein, In 2D augmented reality display mode, the 2D film source projected by the projector generates left circularly polarized light through the polarization generation unit, the polarization-selective holographic microlens array has a defocusing effect on the left circularly polarized light, the light diverged through the polarization-selective holographic microlens array is projected on the optical diffusion element, the optical diffusion element is used as a display screen for receiving 2D images, and 2D image display is realized; meanwhile, ambient light can directly pass through the optical diffusion element into the human eye, so that a viewer in front of the display system can see 2D images and real scenes at the same time, and 2D augmented reality display is realized.

3. The 2D / 3D compatible augmented reality display device of claim 1, wherein, In 3D augmented reality display mode, the 3D film source projected by the projector generates right circularly polarized light through the polarization generation unit, the polarization-selective holographic microlens array has a focusing effect of a lens on the right circularly polarized light, the light is converged, and a 3D image is reconstructed; the 3D image is scattered by the optical diffusion element to form a continuous and smooth 3D image; ambient light can directly pass through the optical diffusion element into the human eye, so that an observer can see virtual 3D images and real scenes at the same time, and 3D augmented reality display is realized.

4. The 2D / 3D compatible augmented reality display device of claim 1, wherein, In the 2D / 3D compatible augmented reality display mode, the 2D / 3D mixed film source projected by the projector passes through the polarization generation unit, and left circularly polarized light 2D film source and right circularly polarized light 3D film source are generated respectively; the polarization selective holographic microlens array has a defocusing effect on the left circularly polarized light 2D film source, the light diverged by the polarization selective holographic microlens array is projected on the optical diffusion element, and the display of the 2D image is realized; the polarization selective holographic microlens array has a focusing effect on the right circularly polarized light 3D film source, the light is converged, and the 3D image is reconstructed, and then scattered by the optical diffusion element to form a continuous and smooth 3D image; the 2D image light and the 3D image light do not affect each other in space, so that the 2D / 3D compatible display is realized; at the same time, the light of the real environment can also directly pass through the optical diffusion element into the human eye, so that the observer can see the real scene while seeing the 2D / 3D mixed image, and the 2D / 3D compatible augmented reality display is realized.

Images