Display devices

Abstract

This invention discloses a display device, including a first optical mirror, a second optical mirror, a flat panel display, a polarizing selective layer, and a quarter-wave plate. The first optical mirror has a first focal point, a first central axis, and a first concave surface. The second optical mirror has a second focal point, a second central axis, and a second concave surface, wherein the first concave surface faces the second concave surface. The flat panel display includes a display surface disposed at the first focal point and facing the first concave surface, and the normal of the display surface is parallel to the first central axis. The polarizing selective layer is disposed on the first concave surface and has a transmission axis. The quarter-wave plate is disposed on the second concave surface, wherein the polarization direction of the image light emitted from the display surface is perpendicular to the transmission axis of the polarizing selective layer.

Description

Technical Field

[0001] This invention relates to a display device. Background Technology

[0002] Currently, there are various naked-eye 3D display technologies, which can be broadly categorized into three types: holographic display, multi-layer splicing, and parallax simulation. Multi-layer splicing utilizes rapid display movement combined with the viewer's visual persistence to create a stereoscopic visual effect in the viewer's brain from the flat image displayed on the screen. Furthermore, multi-layer splicing avoids the discomfort caused by the vergence-accommodation conflict of parallax simulation and does not require the complex equipment of holographic display. However, multi-layer splicing requires a larger space for rapid display movement; therefore, there is an urgent need to develop a multi-layer splicing 3D display that can reduce space requirements. Summary of the Invention

[0003] This invention provides a display device that uses multi-layer splicing 2D images to achieve a stereoscopic visual effect without requiring a large space.

[0004] According to an embodiment of the present invention, a display device is provided, including a first optical mirror, a second optical mirror, a flat panel display, a polarizing selective layer, and a quarter-wave plate. The first optical mirror has a first focal point, a first central axis, and a first concave surface about the first central axis. The second optical mirror has a second focal point, a second central axis, and a second concave surface about the second central axis, wherein the first concave surface faces the second concave surface, and the first central axis overlaps with the second central axis. The flat panel display includes a display surface disposed at the first focal point and facing the first concave surface, and the normal of the display surface is parallel to the first central axis. The polarizing selective layer is disposed on the first concave surface and has a transmission axis. The quarter-wave plate is disposed on the second concave surface, wherein the polarization direction of the image light emitted from the display surface is perpendicular to the transmission axis of the polarizing selective layer.

[0005] Based on the above, the display device provided in this embodiment of the invention utilizes the principle of optical imaging to project a planar image provided by a flat panel display onto a side of the display device adjacent to the first optical mirror. By changing the focal position of the second optical mirror and combining it with the viewer's persistence of vision, a stereoscopic visual effect can be achieved, and the display device does not require a large space.

[0006] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of a display device according to an embodiment of the present invention;

[0008] Figure 2 This is a 3D image schematic diagram of an embodiment of the present invention;

[0009] Figure 3 This is a partial structural schematic diagram of the second optical mirror according to an embodiment of the present invention.

[0010] Symbol Explanation

[0011] 1: Display device

[0012] 100: Monitor

[0013] 100D: Display Surface

[0014] 101: First Optical Mirror

[0015] 101P: Polarizing Selective Layer

[0016] 102, 202: Second optical mirror

[0017] 102H: Through hole

[0018] 102W: Quarter-wave plate

[0019] 102S: Stand

[0020] 202R: High reflectivity layer

[0021] C1, C2: Central axis

[0022] D1, D2, D3, Di: Images

[0023] EY: Eyes

[0024] F1, F2: Focus

[0025] L1, L2, Li, R10, R20, Ri0, R11, R21, Ri1, T1, T2, Ti: Image light; V1, V2: Concave surface Detailed Implementation

[0026] Reference Figure 1 and Figure 2 The display device 1 includes a flat panel display 100, a first optical mirror 101, a second optical mirror 102, a quarter-wave plate 102W, and a polarizing selection layer 101P. The first optical mirror 101 has a focal point F1, a first central axis C1, and a first concave surface V1 about the first central axis C1. The second optical mirror 102 has a focal point F2, a second central axis C2, and a second concave surface V2 about the second central axis C2, wherein the first concave surface V1 faces the second concave surface V2, and the first central axis C1 overlaps with the second central axis C2. The flat panel display 100 includes a display surface 100D, wherein the display surface 100D is disposed at the focal point F1 and faces the first concave surface V1, and the normal of the display surface 100D is parallel to the first central axis C1. The quarter-wave plate 102W is disposed on the second concave surface V2.

[0027] Display 100D emits signals at different times, such as Figure 2 The different images Di are shown. For example, image D1 is emitted at the first time, image D2 is emitted at the second time, image D3 is emitted at the third time, and so on. Each image Di is a two-dimensional planar image.

[0028] Each image Di emitted by the display surface 100D is composed of multiple image beams Li oriented in different directions. The multiple image beams Li travel towards the first concave surface V1 (for ease of understanding, only...). Figure 1 Two example image beams L1 and L2 are illustrated. A polarizing selection layer 101P is disposed on a first concave surface V1 and has a transmission axis. In this embodiment, the plurality of image beams Li emitted from the display surface 100D are s-beams, whose polarization direction is perpendicular to the transmission axis of the polarizing selection layer 101P. That is, the polarization direction of the plurality of image beams Li emitted from the display surface 100D is perpendicular to the transmission axis of the polarizing selection layer 101P, causing the plurality of image beams Li to not penetrate the polarizing selection layer 101P and to be reflected by the polarizing selection layer 101P. However, embodiments of the present invention are not limited thereto. In some embodiments, the plurality of image beams Li emitted from the display surface 100D can be p-beams, and the polarizing selection layer 101P is configured such that its transmission axis is perpendicular to the polarization direction of this p-beam. In some embodiments, the polarizing selection layer 101P is, for example, a birefringent polymer multilayer film (DBEF).

[0029] Because the display surface 100D is positioned at the focal point F1, the multiple image beams Li reflected by the polarizing selection layer 101P will each form multiple image beams Ri0 that are substantially parallel to each other. For example, as... Figure 1 As shown, image beams L1 and L2, after being reflected by the polarizing selective layer 101P, are formed into image beams R10 and R20, respectively, which are approximately parallel. Specifically, due to the small thickness of the polarizing selective layer 101P, the reflective surface of the polarizing selective layer 101P facing the display surface 100D can be considered to be located at the same position as the first concave surface V1. The display surface 100D, which is disposed at the focal point F1 of the first concave surface V1, can be considered to be the focal point of the aforementioned reflective surface disposed on the polarizing selective layer 101P. Therefore, according to the concave mirror imaging principle, the light beam emitted from the display surface 100D, after being reflected by the reflective surface of the polarizing selective layer 101P, will travel parallel to the first central axis C1 of the first concave surface V1. Therefore, the multiple image beams Ri0 will be approximately parallel to each other.

[0030] Multiple image beams Ri0 are incident on the quarter-wave plate 102W, reflected by the second concave surface V2, and then pass through the quarter-wave plate 102W to form multiple image beams Ri1. Because they pass through the quarter-wave plate 102W twice, the polarization direction of the multiple image beams Ri1 is perpendicular to the polarization direction of the multiple image beams Ri0 (i.e., the multiple image beams Ri1 are p-beams), causing the multiple image beams Ri1 to pass through the polarization selection layer 101P and the first optical mirror 101, forming multiple image beams Ti, and imaged at the focal point F2 of the second optical mirror 102. In other words, using the above configuration, multiple images Di emitted from the display surface 100D can be imaged at the focal point F2 of the second optical mirror 102.

[0031] In this embodiment, the focal length of the second optical mirror 102 is greater than that of the first optical mirror 101, causing multiple images Di to be imaged on the side of the display device 1 adjacent to the first optical mirror 101, allowing the viewer's eye EY to see each image Di at the focal point F2. In one embodiment of the invention, the thickness of the first optical mirror 101 is uniform, ensuring that the images Di formed by the image light Ti passing through different parts of the first optical mirror 101 are not distorted. However, the embodiments of the invention are not limited to this, and the thickness of the first optical mirror 101 can be configured to be non-uniform as needed. In one embodiment, the vertical projection of the second concave surface V2 onto a plane perpendicular to the first central axis C1 is greater than or equal to the vertical projection of the first concave surface V1, ensuring that multiple image light Ri0 reflected from the reflective surface of the self-polarizing selective layer 101P can be reflected by the second concave surface V2.

[0032] In one embodiment of the present invention, the first concave surface V1 is spherical, and the display surface 100D relative to the first central axis C1 of the first concave surface V1 falls within a viewing angle of ±3 degrees. In this embodiment, forming the first concave surface V1 as a sphere can reduce manufacturing costs, and the purpose of ensuring that the center of symmetry of the display surface 100D relative to the first concave surface V1 falls within a viewing angle of ±3 degrees is to allow the display surface 100D relative to the first concave surface V1 to be close to a point light source, thereby avoiding various aberrations.

[0033] In one embodiment of the present invention, the first concave surface V1 is configured as an aspherical surface, so that the multiple image lights Ri0 formed after being reflected by the polarization selective layer 101P can be parallel to each other and parallel to the first central axis C1, so as to further focus the multiple image lights Ti on the focal point F2 of the second optical mirror 102, optimize the imaging condition of each image Di, and avoid various aberrations.

[0034] In one embodiment of the present invention, the second concave surface V2 is also configured as an aspherical surface, so that multiple image lights Ti can be focused on the focal point F2 of the second optical mirror 102, thereby optimizing the imaging condition of each image Di and avoiding various aberrations.

[0035] To fully illustrate the various embodiments of the present invention, other embodiments will be described below. It must be noted that the following embodiments use the same element reference numerals and some content as those in the foregoing embodiments, with the same reference numerals representing the same or similar elements, and descriptions of identical technical content omitted. For explanations of the omitted parts, please refer to the foregoing embodiments; these will not be repeated in the following embodiments.

[0036] Reference Figure 3 The diagram illustrates a partial structural schematic of a second optical mirror according to an embodiment of the present invention. In this embodiment, the second optical mirror 202 includes a high-reflectivity layer 202R disposed between the second concave surface V2 and the quarter-wave plate 102W to improve the reflectivity of the image light Ri0. The high-reflectivity layer 202R may, for example, comprise a metal such as silver or aluminum.

[0037] Re-reference Figure 1 The display device 1 may also include multiple supports 102S disposed on the other side of the second optical mirror 102 opposite to the second concave surface V2 for support. However, the invention is not limited thereto. In some embodiments, these supports 102S may be connected to a moving mechanism (not shown) to translate the second optical mirror 102 in the direction along the second central axis C2, correspondingly changing the position of the focal point F2 of the second optical mirror 102, so that different images Di emitted by the display surface 100D at different times are imaged at different positions in space. Combined with the viewer's persistence of vision, the multiple planar images Di generated by the display device 1 can form a three-dimensional image in the viewer's brain, such as... Figure 2 As shown.

[0038] It should be noted that during the translation of the second optical mirror 102, the position of the display surface 100D does not change, but remains at the focal point F1 of the first concave surface V1. Figure 1 In the illustrated embodiment, the second optical mirror 102 has a through hole 102H located on the second central axis C2, and the flat panel display 100 is disposed within the through hole 102H. The flat panel display 100 is not connected to the second optical mirror 102, so that the position of the display surface 100D can remain unchanged during the translation of the second optical mirror 102.

[0039] In one embodiment of the present invention, a plurality of supports 102S are configured to change the shape of the second concave surface V2, for example, to change its radius of curvature, so as to change the position of the focal point F2 of the second optical mirror 102, so that different images Di emitted by the display surface 100D at different times are imaged at different positions in space. Combined with the viewer's visual persistence, the multiple planar images Di generated by the display device 1 can form a three-dimensional image in the viewer's brain.

[0040] In summary, the display device provided in this embodiment of the invention utilizes the principle of optical imaging to project a planar image provided by a flat panel display onto a side of the display device adjacent to the first optical mirror. By changing the focal position of the second optical mirror and combining it with the viewer's persistence of vision, a stereoscopic visual effect can be achieved, and the display device does not require a large space.

Claims

1. A display device, comprising: A first optical mirror has a first focal point, a first central axis, and a first concave surface about the first central axis as an axis of symmetry. The first optical mirror does not have a through hole and has a uniform thickness. The second optical mirror has a second focal point, a second central axis, and a second concave surface about the second central axis. The first concave surface faces the second concave surface, and the first central axis overlaps with the second central axis. The second focal point is located outside the first optical mirror. The vertical projection of the second concave surface on the plane perpendicular to the first central axis is greater than the vertical projection of the first concave surface. A flat panel display includes a display surface, wherein the display surface is disposed at a first focal point and faces a first concave surface, and the normal of the display surface is parallel to the first central axis, wherein a second optical mirror has a through hole located on the second central axis, and the flat panel display is disposed within the through hole, the flat panel display and the second optical mirror are not connected, such that the position of the display surface remains unchanged during the translation of the second optical mirror; A polarizing selection layer is disposed on the first concave surface and has a penetration axis; and A quarter-wave plate, disposed on the second concave surface, A high-reflectivity layer, disposed between the second concave surface and the quarter-wave plate, comprises silver or aluminum. The polarization direction of the image light emitted from the display surface is perpendicular to the transmission axis of the polarizing selective layer. The focal length of the second concave surface is greater than that of the first concave surface. The first concave surface is located between the second focal point and the second concave surface. After being reflected by the second concave surface, the image light passes through the polarizing selective layer and the first optical mirror in sequence and then converges at the second focal point to form an image outside the display device.

2. The display device as claimed in claim 1, wherein the polarization selective layer is a birefringent polymer multilayer film.

3. The display device of claim 1, wherein the first concave surface is aspherical, and the image light travels along a direction parallel to the first central axis after being reflected by the first concave surface.

4. The display device of claim 1, wherein the first concave surface is a sphere, and the center of symmetry of the display surface relative to the first concave surface falls within a viewing angle of ±3 degrees.

5. The display device of claim 1, wherein the second concave surface is an aspherical surface.

6. The display device of claim 1 further includes a plurality of brackets disposed on the other side of the second optical mirror opposite to the second concave surface.

7. The display device of claim 6, wherein the plurality of supports are configured to translate the second optical mirror in a direction along the second central axis.

8. The display device of claim 6, wherein the plurality of supports are configured to change the shape of the second concave surface to change the position of the second focal point of the second optical mirror, such that different images emitted by the display surface at different times are imaged at different positions in space.

Images