TW202134692A - Reflective diffuser projection device having a reflective diffuser and a projection module that projects an image light source toward the reflective diffuser - Google Patents

Abstract

A reflective diffuser projection device has a reflective diffuser, and a projection module that projects an image light source toward the reflective diffuser. The reflective diffuser has a micro-mirror array formed by continuously staggering at least one concave mirror and at least one convex mirror. A boundary between the adjacent concave mirror and the convex mirror forms a smooth curved surface. In this way, the singularity of the dramatic change in curvature is eliminated, the light beam will not be diffused in all directions, and viewers will not see the light spots, thereby greatly improving picture quality.

Description

Reflective diffuser projection device

The invention relates to a reflective diffuser projection device, which can reduce light spot generation and improve image quality.

As shown in Figure 1, the conventional micro-mirror array 91, through a specially designed micro-concave mirror or micro-convex mirror, after reflection, the directivity spreads to the eye box 92 area of the viewer. Such a large number of micro-mirror arrays will have multiple beams. The light 93 spreads to the eye box 92, allowing the viewer to see the complete image. Such a micro-mirror array 91 can be distributed on a plane, as shown in FIG. 2, or on a curved surface.

As shown in FIG. 3, when the light beam 93 hits the designed micromirror array 91 area, the range of diffusion will be scattered within the designed angle. If a light beam 93 hits an area that exceeds a single micromirror, that is, at the junction 94 of the micromirror and the adjacent micromirror, this area is a geometric singularity due to the rapid curvature of the micromirror, and the light beam will diffuse in all directions. A part of it will enter the eye box 92, allowing the viewer to see weird light spots on the display screen, thereby degrading the image quality. The light spot occurs at the interface 94 of the micro-concave mirror and the micro-concave mirror, as shown in Figure 4, and may also appear at the interface 94 of the micro-convex mirror and the micro-convex mirror.

For related technologies using micromirror arrays or enhancing the resolution of reflective display devices, please refer to the following patents, such as I622505, TW 201636680, I367405, I449950, M455182, I506299, TW201624101, I479236, and I485432. In these previous cases, micro-arrays of fully convex mirrors or fully concave mirrors are commonly used. In order to improve the resolution, each micromirror is also fine-tuned to direct the light to the correct direction. However, this method will result in the provision of actuation units. And adjust the construction cost of the unit.

Based on the above deficiencies, the present invention provides a reflective diffuser projection device, which can reduce the generation of light spots and improve the image quality.

According to the foregoing objective, the present invention provides a reflective diffuser projection device having a reflective diffuser, and a projection module that projects an image light source toward the reflective diffuser, wherein the reflective diffuser is at least one concave mirror and at least one Convex mirrors are continuously staggered to form an array of micro mirrors, and the junction of adjacent concave mirrors and convex mirrors forms a smooth curved surface.

In this way, the micro-mirrors (that is, the aforementioned concave mirror and convex mirror) can reflect and diffuse the projected image light source to a predetermined diffusion area. The designed diffusion areas of the micro-mirrors at different positions can be the same or different. The intersection of the diffusion areas of these micro-mirrors is the Eye Box. As long as the human eye is within the eye box, the projected image can be seen.

Wherein, the four boundaries of the micromirror can be set as four straight lines, or there are two straight lines and two curves, or there are four curves. After the rectangular array is arranged, the boundary of the adjacent micromirrors is smooth. Surface.

Wherein, the horizontal axis of the micromirror array is that the concave mirror and the convex mirror are alternately arranged, and the adjacent concave mirror and the convex mirror are connected in such a way that a straight line corresponds to a straight line or a curve corresponds to a curve to form a smooth curved surface.

Wherein, when the four boundaries of the micro mirror are all curved, the four boundaries of the convex mirror are all convex upward curves, and the four boundaries of the concave mirror are two convex upward curves and two concave downward curves. The convex curve of one boundary is connected with the convex curve of one of the adjacent convex mirrors to form the smooth curved surface.

Wherein, when the four boundaries of the micro mirror are all curves, the four boundaries of the convex mirror are two convex curves and two concave curves. The four boundaries of the concave mirror are all concave curves. The concave curve of one boundary is connected with the concave curve of one of the adjacent convex mirrors to form the smooth curved surface.

Wherein, the reflective diffuser is a flat micro-mirror array or a curved micro-mirror array.

In the present invention, the micro-mirror array is designed as a continuous interlacing of a concave mirror and a convex mirror, forming a smooth curved surface at the junction of adjacent micro-mirrors. In this way, there is no more singularity with sharp curvature changes at the junction, the light beam will not diffuse in all directions, and the viewer will not see the light spot, which can greatly improve the picture quality.

In order to illustrate the specific structure and effect of the present invention, an embodiment is provided and described in conjunction with FIGS. 5 to 11. This embodiment is a reflective diffuser projection device, including a projection module 1 and a reflective diffuser 2 .

The projection module 1 projects an image light source L.

In this embodiment, the reflective diffuser 2 is a flat micromirror array, and the image light source L from the projection module 1 is projected toward the reflective diffuser 2. Another embodiment provided by the present invention is shown in FIG. 6. The main difference is that the reflective diffuser 2 is a curved micromirror array.

Specifically, the reflective diffuser 2 is an array of micro-mirrors in which a concave mirror 21 and a convex mirror 22 are continuously interlaced, and the junction 23 between the adjacent concave mirror 21 and the convex mirror 22 is formed as a smooth curved surface. Thereby, the micro-mirrors (that is, the concave mirror 21 and the convex mirror 22) can reflect and diffuse the image light source L from the projection module 1 to a diffusion area, and the preset diffusion areas of the micro-mirrors at different positions can be the same. It can also be different, and the intersection range of the preset diffusion areas of these micro-mirrors is the eye box 3 (Eye Box), as long as the human eye is within the range of the eye box, the projected image can be seen.

Since the junction 23 between the adjacent concave mirror 21 and the convex mirror 22 is made into a smooth curved surface, there is no more singularity with sharp curvature changes, the image light source L will not diffuse in all directions, and the viewer will not You will see light spots, which can greatly improve the picture quality. The light projected on the junction 23 of the micro-mirror may be reflected once or twice. Although there is still a chance of entering the eye box 3, compared with the previous geometric singularity diffused in all directions, the probability of occurrence has been greatly reduced. .

The geometric curved surface design of the micromirror is related to whether the concave mirror 21 and the convex mirror 22 can be continuously and staggered to avoid geometric singularities. In the design of the micromirror arranged in a rectangular array, the four boundaries of the reflective surface can be added. Classification. As shown in Figure 7, the first type is that the four boundaries are all straight lines (the micro-mirror in the upper left of Figure 7), and the second type is two straight lines and two curves (the micro-mirror in the upper right of Figure 7) , The third type is that the four boundaries are all curved (as shown in the micro-mirror at the bottom of Figure 7).

As shown in Figure 8, the first type of micro-mirror is used, that is, the four boundaries of the micro-mirror are all straight lines. After the rectangular array is arranged, the junctions 23L and 23P of the adjacent micro-mirrors in the horizontal and vertical directions are no longer A geometric singularity appears, but a smooth surface. From the perspective of the horizontal and vertical axis, the smooth curved surface at different depth positions can reduce the generation of light spots and improve the image quality.

Wherein, the horizontal axis of the micromirror array is staggered with the concave mirror 21 and the convex mirror 22, and the longitudinal axis of the micromirror array is staggered with the concave mirror 21 and the convex mirror 22.

As shown in Figure 9, the second type of micro-mirror is adopted, that is, the four boundaries of the micro-mirror have two straight lines and two curves. The height and curvature are designed so that the concave mirror 21 and the convex mirror 22 are in a straight line. Can be connected to form a smooth surface.

Wherein, the horizontal axis of the micromirror array is staggered with the concave mirror 21 and the convex mirror 22, and the geometric singularity no longer appears at the adjacent junction 23L in the lateral direction, but a smooth curved surface. The longitudinal axis of the micromirror array The same micro-mirror arrangement is maintained, with one row of concave mirrors 21 and one row of convex mirrors 22, so there is still a geometric singularity at the longitudinally adjacent junction 23P. The reflective diffuser 2 can be applied to a projector that scans in the horizontal direction, and the probability of the light beam hitting the horizontal interface is relatively high, so it can still reduce the generation of light spots and improve the image quality.

As shown in Figure 10, the third type of micro-mirror is used, that is, the four boundaries of the micro-mirror are all curved, and the four boundaries of the convex mirror 22 are all up-convex curves. The concave mirror 21 has two up-convex curves and two A concave curve, the height and curvature are designed so that the curve of one of the boundaries of the concave mirror 21 and the curve of one of the boundaries of the convex mirror 22 can be exactly connected to form a smooth curved surface.

Wherein, the horizontal axis of the micromirror array is staggered with the concave mirror 21 and the convex mirror 22, and the geometric singularity no longer appears at the adjacent junction 23L in the lateral direction, but a smooth curved surface. The longitudinal axis of the micromirror array The same micro-mirror arrangement is maintained, with one row of concave mirrors 21 and one row of convex mirrors 22, so there is still a geometric singularity at the longitudinally adjacent junction 23P. The reflective diffuser 2 can be applied to a projector that scans in the horizontal direction, and the probability of the light beam hitting the horizontal interface is relatively high, so it can still reduce the generation of light spots and improve the image quality.

As shown in Figure 11, the third type of micro-mirror is also used, but the four boundaries of the convex mirror 22 are two convex curves and two concave curves. The four boundaries of the concave mirror 21 are all concave curves. The design of curvature and curvature allows the curve of one of the boundaries of the concave mirror 21 and the curve of one of the boundaries of the convex mirror 22 to be exactly connected to form a smooth curved surface.

Wherein, the horizontal axis of the micromirror array is staggered with the concave mirror 21 and the convex mirror 22, and the geometric singularity no longer appears at the adjacent junction 23L in the lateral direction, but a smooth curved surface. The longitudinal axis of the micromirror array The same micro-mirror arrangement is maintained, with one row of concave mirrors 21 and one row of convex mirrors 22, so there is still a geometric singularity at the longitudinally adjacent junction 23P. The reflective diffuser 2 can be applied to a projector that scans in the horizontal direction, and the probability of the beam hitting the horizontal interface is relatively high, so it can still reduce the generation of light spots and improve the image quality.

By designing the micro-mirror as a continuous staggered arrangement of a concave mirror and a convex mirror, the junction of adjacent micro-mirrors can be made into a smooth curved surface. In this way, there is no more singularity with sharp curvature changes at the junction, the light beam will not diffuse in all directions, and the viewer will not see the light spot, which can greatly improve the picture quality.

1: Projection module 2: Reflective diffuser 21: Concave mirror 22: Convex mirror 23, 23L, 23P: junction 3: eye box L: image light source 91: Micro mirror array 92: Eye Box 93: beam 94: light spot

Fig. 1 is a schematic diagram of a conventional projection device.

FIG. 2 is a schematic diagram of another implementation of the conventional projection device.

Figures 3 and 4 are schematic diagrams of the singularity at the junction of the micro-mirror of the conventional projection device.

FIG. 5 is an embodiment of the reflective diffuser provided by the present invention as a flat micromirror array.

6 shows another embodiment of the present invention. The reflective diffuser is a curved micromirror array.

FIG. 7 shows the geometrical curved surface design of the micro-mirror used in the embodiment of the present invention.

FIG. 8 is a schematic diagram of the horizontal axis and the vertical axis of a micromirror array in an embodiment of the present invention.

9 is a schematic diagram of the horizontal axis and the vertical axis of another micromirror array in an embodiment of the present invention.

10 is a schematic diagram of the horizontal axis and the vertical axis of another micromirror array in an embodiment of the present invention.

11 is a schematic diagram of the horizontal axis and the vertical axis of another micromirror array in an embodiment of the present invention.

1: Projection module

2: Reflective diffuser

21: Concave mirror

22: Convex mirror

23: Junction

3: eye box

L: image light source

Claims (10)

A reflective diffuser projection device includes a reflective diffuser and a projection module that projects an image light source toward the reflective diffuser, and is characterized in that: The reflective diffuser is a micromirror array in which at least one concave mirror and at least one convex mirror are alternately arranged, and the image light source is reflected and diffused to a diffusion area, wherein the boundary between the adjacent concave mirror and the convex mirror is a smooth curved surface. The reflective diffuser projection device according to claim 1, wherein the four boundaries of the at least one concave mirror and the at least one convex mirror are all straight lines. The reflective diffuser projection device according to claim 2, wherein a horizontal axis and a vertical axis of the micromirror array are both the at least one concave mirror and the at least one convex mirror in a staggered arrangement. The reflective diffuser projection device according to claim 1, wherein the four boundaries between the at least one concave mirror and the at least one convex mirror have two straight lines and two curved lines, and the concave mirror and the convex mirror are two adjacent ones of straight lines The boundaries meet to form the smooth surface. The reflective diffuser projection device according to claim 4, wherein a horizontal axis of the micromirror array is alternately arranged with the at least one concave mirror and the at least one convex mirror, and a longitudinal axis of the micromirror array is the At least one concave mirror or the at least one convex mirror is arranged continuously. The reflective diffuser projection device according to claim 1, wherein the four boundaries of the at least one concave mirror and the at least one convex mirror are all curved, the four boundaries of the at least one convex mirror are all upward convex curves, and the at least one concave mirror The four boundaries of the at least one concave mirror are two convex curves and two concave curves. The convex curve of one boundary of the at least one concave mirror is connected with the convex curve of one of the adjacent convex mirrors to form the smooth curved surface. The reflective diffuser projection device according to claim 6, wherein a horizontal axis of the micromirror array is alternately arranged with the at least one concave mirror and the at least one convex mirror, and a longitudinal axis of the micromirror array is the At least one concave mirror or the at least one convex mirror is arranged continuously. The reflective diffuser projection device according to claim 1, wherein the four boundaries of the at least one concave mirror and the at least one convex mirror are all curved, and the four boundaries of the convex mirror are two upper convex curves and two lower concave curves, The four boundaries of the concave mirror are all concave curves, and the concave curve of one boundary of the at least one concave mirror is connected with the concave curve of one of the adjacent convex mirrors to form the smooth curved surface. The reflective diffuser projection device according to claim 8, wherein a horizontal axis of the micromirror array is staggered with the at least one concave mirror and the at least one convex mirror, and a longitudinal axis of the micromirror is the at least one The concave mirror or the at least one convex mirror are arranged continuously. The reflective diffuser projection device according to any one of claims 1 to 9, wherein the reflective diffuser is a flat micromirror array or a curved micromirror array.

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