JP2003255242A - Optical switching device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical switching device in which a high quality image having a high contrast ratio, brightness and no unevenness is displayed by eliminating the influence of diffraction light. <P>SOLUTION: In the optical switching device 10 having a matrix part 11 on which a plurality of optical switching elements 20 which switch incident light 71 by varying the angle of reflection faces 21 are arranged in the row direction m and the column direction n, the form of micromirrors (reflection faces) 21 are formed into a hexagon which is formed with lines nonparallel in the row direction m. Thus, when an incident direction 81 and a switching direction 83 are in the column direction n, the angle of emitting direction of diffracted light 73a is varied with respect to the incident direction 81, the optical system is arranged in the direction perpendicular to the image. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical switching device used for a display, a projector device, a printing device and the like.

[0002]

2. Description of the Related Art As a light valve for a projector or the like, an optical switching device such as a DMD (digital mirror device) is known in which a micromirror is mechanically driven at high speed and its angle is changed to turn on / off light.
The micromirror device has a faster response speed than a liquid crystal device and can obtain a bright image. Therefore, the micromirror device is suitable for realizing an image display device such as a compact projector having high brightness and high quality. An example of an image display device using a micromirror device is shown in FIG. The projector 90 includes a white light source 91 and a light beam 7 from the light source 91.
A collimator lens 92 for collimating 1 and a rotary color filter 93 for time-division of these light beams 71 into three primary colors.
And a motor 93M that rotationally drives the filter 93. Further, the projector 90 is driven in synchronization with the lens 94 that condenses the time-divided light flux 71 on the micromirror device 95 and the light flux 71 of each color, and modulates the light of each color to generate a multi-colored light. A micro mirror device 95 for generating an image and a projection lens 96 for projecting the modulated light flux (display light) 72 are provided, and the projector 90 projects a multi-color image on a screen 97.

FIG. 12 is a plan view showing a part of the structure of the micromirror device 95. In the micromirror device 95, switching elements 98 each having a plurality of minute, rectangular mirror surfaces (micromirrors) 98a of about 16 μm square are arranged regularly in a row direction m and a column direction n in an array or matrix. Each of the micro-mirrors 98a is provided with a matrix 99, and pixels, which are units for forming an image, are displayed on and off. Therefore, each switching element 98 has a micromirror 9
By changing the diagonal angle of the matrix 99 of 8a,
The light (incident light) 71 incident from the diagonal direction is switched to be emitted as the emitted light 72 from the diagonal direction. That is, the switching direction 83 of the micromirror element 98 and the incident direction 81 of light are both in the diagonal direction of the matrix 99.

FIG. 13 shows an enlarged structure of the switching element 98. The micromirror 98a of each switching element 98 is supported at its center on the semiconductor substrate 31 via the post 34.
A pair of address electrodes 32a and 32b functioning as the actuator 30 are formed on the surface of the semiconductor substrate 3 and
It is driven by the drive circuit built in 1. Therefore, in the switching element 98, the address electrode 32
When a voltage is applied to a, the micromirror 98a turns from the horizontal state around the column 34 as shown by the broken line in FIG. 13, and tilts toward the electrode 32a, to the left in this figure. Therefore, when the incident light flux 71 is incident from the left side, the incident light 71 is reflected by the tilted micro mirror 98a, and the emitted light 72 is output in the vertical direction. Therefore, if the projection lens 96 is arranged in the direction perpendicular to the switching element 98, this state is turned on.

On the other hand, when a voltage is applied to the electrode 32b,
The micro mirror 98a turns to the opposite side and tilts to the right in this figure. For this reason, the incident light 71 is reflected to the right and deviates from the projection lens 96, so that it becomes invalid light 73 and the switching element 98 is turned off. In this way, the switching element 98 can switch the incident light 71 by changing the angle (tilt) of the micro mirror 98a by the actuator 30.

[0006]

In the projector 90 which employs the micromirror device 95 as a light valve, in order to display a clear, bright and high-contrast image, the light reflected by the micromirror 98a in the ON state is effective. The reflected light (effective light) 72 is captured by the projection lens 96 so as not to be wasted, and the invalid reflected light (ineffective light) 73 reflected by the micromirror 98a in the off state is not put into the projection lens 96 and is eliminated as much as possible. There is a need to.

The tilt angle of the micro mirror 98a is ± 10.
The reflected light 72 is switched between the effective reflected light 72 and the invalid reflected light 73 within the angle. Therefore, it is necessary to install the projection lens 96 at a position where the effective light 72 and the ineffective light 73 can be separated with such a small angle difference. Therefore, the effective light 72 and the ineffective light 73 can be easily separated by increasing the distance between the micro mirror device 95 and the projection lens 96 or decreasing the diameter of the input side of the projection lens 96. However, the micromirror device 95
If the distance between the projector 9 and the projection lens 96 is increased, the projector 9
The size of 0 becomes large. In addition, the projection lens 9
If the input diameter of 6 is reduced, the micromirror device 9
I can't capture all the light reflected at 5, so
The image displayed on the screen 97 becomes dark.

Therefore, the diameter of the projection lens 96 on the input side is made as large as possible, and the effective light 72 and the ineffective light 7 are added.
The projection lens 96 is arranged at a limit position where 3 can be separated. In the micromirror device 95, it is also necessary to consider the diffracted light output from the micromirror device 95. That is, in the micromirror device 95, the micromirrors 98 a are arranged in a matrix, so that the micromirror 98 is mainly used.
The diffracted light resulting from the diffraction of the edge portion of a is output in the direction deviated from the direction of the micromirror 98a by the diffraction angle. Therefore, when the incident light 71 is irradiated along the row direction m or the column direction n of the matrix 99 shown in FIG. 12 and the micromirror 98a is driven to rotate in the row direction m or the column direction n, the micromirror 98a is tilted to the right. When turned off, the first-order diffracted light is also output in the vertical direction from the micromirror 98a tilted to the right. That is, since the turning direction of the micro mirror 98a and the turning direction of the diffracted light coincide with each other, the emitting direction of the effective light 72 and the ineffective light 7
The outgoing directions of the diffracted light of No. 3, particularly the first-order diffracted light of high intensity are close to each other. For this reason, the diffracted light of the ineffective light 73 cannot be distinguished from the effective light 72, which causes a decrease in contrast.

Therefore, in the micromirror device 95 shown in FIG. 12, the incident light 71 is irradiated in the diagonal direction of the matrix 99, and the micromirror 98a is also driven in the diagonal direction, so that the micromirror 98 is driven.
The outgoing direction of the diffracted light at the edge 98b of a does not coincide with the driving direction of the micro mirror 98a.

Therefore, the arrangement of the optical system including the light source 91, the projection lens 96 and the like with respect to the micromirror device 95 is limited. That is, when a square image is to be displayed by the matrix unit 99 of the micromirror device 95, an optical system must be arranged so that light is input and output obliquely to the square image, so that it is perpendicular to the image. Alternatively, the projection lens and the light source cannot be arranged in parallel directions. Therefore, when the projection lens and the light source are to be housed together with the micromirror device in the housing to form the projector, it is impossible to arrange them in the horizontal or vertical direction to realize a compact projector. Not limited to the projector, other equipment using the micromirror device, for example,
The same applies to optical printers and the like.

There is also a problem that the optical element developed for a liquid crystal projector cannot be used as it is for a micromirror device because the irradiation direction is not parallel or perpendicular to the image. For example, even in an integrator, the direction of light development is not perpendicular or horizontal to the direction of illumination, so it is not possible to use a liquid crystal panel equipped with a rectangular lens, and either develop a new one or increase the brightness in an oblique direction. It is necessary to tolerate the unevenness.

Therefore, by adopting the micromirror device, it is possible to display an image with high resolution and a high contrast ratio, but it is difficult to miniaturize and thin an apparatus using the micromirror device such as a projector.

Therefore, in the present invention, it is an object of the present invention to realize a switching device which performs switching by changing the angle of a micromirror, and which can display an image by irradiating light from the vertical or horizontal direction of the image. I am trying. The object of the present invention is to realize a smaller and thinner image display device that can display or output a high-contrast and bright image using the switching device.

[0014]

Therefore, in the optical switching device of the present invention, the shape of the reflecting surface of each optical switching element arranged in a matrix is parallel to the row or column direction as in the conventional case. By making the shape non-parallel, which is different from the rectangular shape consisting of sides, the angle of the diffracted light is parallel to the exit direction even if light is incident in the matrix row direction or column direction I try not to become.

That is, the optical switching device of the present invention comprises a matrix portion in which a plurality of optical switching elements for switching incident light by changing the angle of the reflecting surface are arranged in at least one row or one column. The sides of the reflecting surfaces arranged so as to define the arrangement of the matrix portion in the row direction and / or the column direction are not parallel to the row direction and / or the column direction. In this optical switching device, the side of the reflecting surface, that is, the side of the micromirror is not parallel to the row direction or the column direction of the matrix portion in at least one of the row direction and the column direction. Therefore, when light is emitted from the direction perpendicular to the direction in which the sides of the micromirrors are not parallel to the row or column direction of the matrix portion in the row or column direction, the outgoing direction of the diffracted light is , Different from the emission direction of the effective light emitted from the micromirror. That is, in the optical switching device of the present invention, when the turning direction of the micromirror is set to the row direction or the column direction so as to switch the incident light from the row direction or the column direction, the turning direction of the micromirror and the diffracted light are The direction of emission is different. Therefore, light can be incident from the row direction or the column direction.

For example, if the sides of the reflecting surfaces (micromirrors) arranged so as to define the array in the row direction of the matrix portion serving as a switching area for displaying a square image are not parallel to the row direction, this reflection is performed. Even if the surface is driven in the column direction and the incident light is irradiated in the column direction, the diffracted light is not emitted in the column direction. On the other hand, if the sides of the reflective surfaces that are arranged so as to define the array in the column direction of the matrix part that becomes the switching area for displaying a rectangular image are not parallel to the column direction, drive this reflective surface in the row direction. However, even if the incident light is irradiated in the row direction, the diffracted light is not emitted in the row direction. Therefore, with the optical switching device of the present invention, the influence of diffracted light can be eliminated without making the incident direction oblique, and the optical system such as the light source and the projection lens can be vertically or horizontally oriented with respect to the image. Can be placed in Further, even if there is a difference between the transmissive type and the reflective type, the optical system can be arranged in the vertical or horizontal direction with respect to the image like the conventional liquid crystal panel, so that the conventional optical element can be used.

Therefore, the optical switching device of the present invention, the light source device for irradiating the matrix portion of the optical switching device with incident light from the row direction and / or the column direction thereof, and the row direction of the matrix portion of the optical switching device. And / or a lens system for projecting modulated light reflected in the column direction,
It can be made compact while taking advantage of the characteristics of the micromirror device. Therefore, it is possible to provide an image display device such as a small or thin projector that has high responsiveness, high resolution, high contrast, and can display high quality images. Further, even in an optical element such as an integrator, the illumination direction can be horizontal or vertical, so that unevenness in the brightness of the projected image can be eliminated by the integrator using a rectangular lens for a liquid crystal projector. Therefore, by using the micromirror device, it is possible to provide a compact image display device with good optical performance at low cost.

With respect to the row or column direction of the matrix part,
It becomes non-parallel by tilting the sides of the reflecting surface. For this purpose, the reflecting surface may be formed of a polygon having sides inclined with respect to the row or column direction of the matrix portion. For example, by forming the reflecting surface in a hexagonal shape, the side defining the row or column direction can be inclined with respect to the row or column direction of the matrix portion. Also, by forming the reflecting surface into a trapezoid or a parallelogram including a rhombus, the sides defining the row or column direction can be slanted.

Also, by making the sides defining the row or column direction of the reflecting surface curved, the sides are not parallel to the row or column direction of the matrix portion, so that the irradiation direction of the diffracted light can be changed.

Adjacent reflecting surfaces can be arranged close to each other by forming a plurality of reflecting surfaces including these non-parallel sides so as to complement the opposite sides of the reflecting surfaces.
Therefore, since the matrix portion can be formed by the densely arranged reflecting surfaces, the reflection efficiency is improved. Since there is no gap between the reflecting surfaces, it is possible to provide an optical switching device that is projected but does not separate and can display a seamless bright image. Therefore, each optical switching element for forming the optical switching device having the matrix portion of the present invention in which the reflecting surfaces are densely arranged is an optical switching element that switches incident light by changing the angle of the reflecting surface. The reflecting surface has a first set of sides facing the first direction for driving the reflecting surface and a second set of sides facing in a direction orthogonal to the first direction, and the first set of sides. Are shapes that are non-orthogonal to the first direction and complement each other, and the sides of the second set are
The shapes complement each other.

On the other hand, when the opposite sides do not have a complementary shape, the reflecting surfaces can be arranged densely by shifting the reflecting surfaces by a half pitch in the row direction and / or the column direction, so that the reflecting surfaces can be arranged densely. An optical switching device capable of displaying a bright image can be provided.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) An embodiment of the present invention will be described below with reference to the drawings. Figure 1
FIG. 1 shows a schematic configuration of a projector 1 equipped with the optical switching device 10 of the present invention. This projector 1 includes a light source 61 that outputs white light 71, a condenser lens (rod lens) 62, a color separation filter 63 that time-divides the white light 71 into three primary colors, and a color-separated light beam that is incident light 71. And a mirror 64 for irradiating the optical switching device 10. Further, a projection lens 65 that irradiates the front screen 66 with the light flux 72 modulated by the optical switching device 10 to form a color image on the screen 66 is provided. Then, the optical system including the light source 61, the condenser lens 62, the color separation filter 63, the mirror 64, and the projection lens 65 has substantially the same surface in the direction perpendicular to the matrix portion 11 of the optical switching device 10 of this example. It is arranged to make up.

The optical switching device 10 of the present example is provided with a plurality of optical switching elements 20 for switching the incident light 71 by changing the angle of the micro mirror described above with reference to FIG. 13 by the actuator 30. The matrix section 11 is provided in which these are arranged in a matrix. Individual optical switching element 20
The mechanism is similar to that described with reference to FIG. 13 except for the shape and driving direction of the micromirror (reflection surface) described below. Then, a mechanism 42 that supplies (generates) the video signal φ.
The optical switching device 10 is controlled by the control mechanism 41 including a circuit 43 for generating pixel reproduction data based on the video signal φ, and a circuit 44 for driving the optical switching device 10 serving as a light valve by the generated data.
Is controlled.

FIG. 2 shows an enlarged view of a part of the matrix portion 11 of the optical switching device 10. In the matrix section 11, the micromirrors 21 as reflecting surfaces form a two-dimensional matrix or array in the row direction m (horizontal direction in this figure) and the column direction n (vertical direction in this figure). A plurality of optical switching elements 20 are arranged. Each of the micromirrors 21 is a hexagon that is convex in the vertical direction (column direction n) and is point-symmetrical, and has six sides 21a to 2a.
Of 1f, the sides 21a and 21b and the sides 21d and 21e that define the array in the row direction m along the row direction m are inclined with respect to the row direction m and are non-parallel as the first set of sides. Has become. On the other hand, the other two sides 21c and 2
If is a side of the second set and is parallel to the column direction n. This second set of sides (sides 21c and 21f)
Are shapes that can face each other in the direction orthogonal to the switching direction (first direction) 83 and can be complemented by arranging them so as to be displaced by a half pitch p.

These micro mirrors 21 are arranged row by row in the row direction m by a half pitch p, that is, shifted so that the respective micro mirrors 21 are displaced by half, and a plurality of matrix portions 11 are densely arranged with almost no space therebetween. Are arranged so as to be filled with the micro mirror 21. Therefore, almost all the light 71 incident on the matrix portion 11 is switched by the respective micro mirrors 21, so that the light utilization efficiency is high and there is no gap between pixels, so that the arrangement is such that a seamless image can be displayed. Has become.

In these optical switching elements 20, the micro mirrors 21 are driven so that the column direction n is the switching direction 83. Therefore, the incident direction of the incident light 71, that is, the component projected on the plane of FIG. 2 (referred to as the incident direction 81) coincides with the column direction n.
For example, the incident light 71 is incident on the micro mirror 21 from below in FIG. That is, the incident light 71 is incident so as to be orthogonal to the row direction m from the direction perpendicular to the row direction m. The plane in FIG. 2 is a plane including the row direction m and the column direction n. The component obtained by projecting the emission direction of the switched light 72 on the plane of FIG. 2 also matches the column direction n.
On the other hand, as described above, the row direction m of the micromirror 21.
21a and 21b, 21d and 21
e is inclined and non-parallel to the row direction m.
Therefore, the sides 21a and 21b and the sides 21d and 21e that define the row direction m are a first set of sides facing each other in the column direction n and are orthogonal to the column direction n that is the switching direction 83 of the micromirror 21. I haven't. These first set of sides, namely sides 21a and 21b, side 2
First-order diffracted light 73 of ineffective light diffracted by 1d and 21e
The light a is emitted in a direction different from the column direction n which is the incident direction 81 and the switching direction (driving direction) 83.

As described above, in the optical switching device 10 of this example, light can be incident in the column direction n of the matrix portion 11 to switch it, and the diffracted light 73 at that time can be switched.
Since the direction of a and the switching direction 83 of the incident light 71, that is, the turning direction of the micro mirror 21, are different,
The diffracted light 73a of the invalid light 73 is difficult to be captured by the projection lens 66. Further, the column direction n of the matrix portion 11 in which the switching elements 20 are arranged in the row and column directions coincides with the vertical direction of the rectangular image formed by the optical switching device 10. Therefore, in the optical switching device 10 of the present example, it is desirable that the incident and outgoing directions be perpendicular to the image, and the first-order diffracted light from the matrix section 11 is output in an oblique direction with respect to the image. Projection lens 66
The ineffective light 73 even if it is brought close to the optical switching device 10.
The arrangement that is not affected by the diffracted light 73a is possible.

Therefore, by adopting the optical switching device 10 of this example, as shown in FIG. 1, the optical system from the light source 61 to the projection lens 66 is arranged so that the light enters and exits in the direction perpendicular to the image. It becomes possible to do. Therefore, in the projector 1 of the present example, by arranging the light source 61, the projection lens 66, and the like that form the optical system vertically or horizontally with respect to the image, the structure of the parts is simple, and the entire structure is small and thin. can do.
Since the optical system can be configured in the vertical or horizontal direction with respect to the image, it becomes possible to directly apply the optical element such as an integrator developed in the conventional liquid crystal projector. Therefore, it is possible to provide a projector capable of displaying a high-quality image at a low cost, by further utilizing the characteristics of the micromirror type optical switching device capable of displaying a high-resolution and high-contrast image.

(Second Embodiment) FIG. 3 shows a matrix section 12 of a different optical switching device 10 according to the present invention.
Are shown enlarged. In each of the examples of the optical switching device described below, optical switching elements using micromirrors are arranged in a matrix, and the main configuration is the same as that of the optical switching device described above. Therefore, the description of the same parts as those of the above optical switching device will be omitted.

Each reflecting surface 22 constituting the matrix portion 12 of the present example is a hexagon that is convex upward and concave downward in the column direction n. Therefore, of the six sides 22a to 22f, the sides 22a and 22b that define the row direction m and the side 2
2d and 22e are inclined in an inverted V shape and are not parallel to the row direction m, that is, not parallel. On the other hand, the remaining sides 22c and 22f are both formed by straight lines parallel to the column direction n.

Therefore, the micromirror 22 of this example
Also, the sides 22a and 22b, 22d forming the row direction m
And 22e are inclined and non-parallel to the row direction m. The side 22 that defines the row direction m
The sides a and 22b and the sides 22d and 22e are the first set of sides facing each other in the column direction n and are not orthogonal to the column direction n which is the driving direction 83 of the micromirror 22. Then, the sides 22a and 22b and the side 22d of these first set
And the first-order diffracted light 73 of the ineffective light 73 diffracted by 22e
a is a column direction n which is the incident direction 81 and the driving direction 83.
Is emitted in a direction different from. Therefore, like the optical switching device described above, the optical switching device of the present example can also arrange the optical system in the direction vertical or horizontal to the image, and can configure the compact projector 1.

Further, the micro mirror 22 of this embodiment has a shape in which the sides 22a and 22b of the first set and the sides 22d and 22e facing each other in the column direction n complement each other. That is, the upper sides 22a and 22b are concave upwards, the lower sides 22d and 22e are convex downwards, and the upper sides 22a and 22b and the lower side 2 are
2d and 22e can be placed adjacent. Therefore, unlike the matrix section 11 described above, the matrix section 1 of the present example
In No. 2, the micro mirrors 22 can be densely arranged without being displaced by a half pitch.

(Third Embodiment) FIG. 4 is an enlarged view of a matrix portion 13 of a different optical switching device 10 according to the present invention. Each micro mirror (reflection surface) 23 that constitutes the matrix portion 13 of this example is also a hexagon that is convex upward and concave downward. Therefore, the six sides 23a
Of 23 f, the sides 23a and 23 that define the row direction m
b and sides 23d and 23e are inclined in an inverted V shape and are not parallel to the row direction m. Further, the remaining sides 23c and 23f defining the column direction n are also tapered so as to narrow upward or downward, and these sides 23c and 23f are also not parallel to the column direction n.

Therefore, the micromirror 23 of this example
Also, similarly to the above-described embodiment, the row direction m is configured,
The sides 23a and 23b, 23d and 23e facing the column direction n are inclined and non-parallel to the row direction m and are orthogonal to the column direction n which is the driving direction (switching direction) 83 of the micromirror 23. Absent. Therefore, the first-order diffracted light of the ineffective light diffracted by the sides 23a and 23b and the sides 23d and 23e is emitted in a direction different from the column direction n which is the driving direction 83.

Furthermore, the micromirror 23 of the present example defines the column direction n and faces the row direction m in a second set of sides 23c.
And 23f are not parallel to the column direction n and are not orthogonal to the row direction m. Therefore, the driving direction 83 of the micromirror 23
Even when light is incident in the row direction m with the row direction m, switching can be performed without being affected by the diffracted light as in the above. Therefore, also in the optical switching device of this example, the optical system can be arranged in the direction vertical or horizontal to the image, and the compact projector 1 can be configured.

Further, in the micromirror 23 of this example, the sides 23a and 23b facing each other in the column direction n and the sides 23d and 23e complement each other, and the micromirrors 23 are arranged at a half pitch in the row direction. It is possible to arrange them densely without shifting. On the other hand, the row direction m
The sides 23c and 23f facing each other are not shaped to complement each other, but by changing the directions of the adjacent micromirrors 23, the sides 23c facing each other in the row direction m.
By inverting the directions of the taper (inclination) of 23f and 23f, a dense arrangement is possible.

(Fourth Embodiment) FIG. 5 is an enlarged view showing a part of the shape of the matrix portion 14 of a further different optical switching device 10 of the present invention. Each micro mirror (reflection surface) that constitutes the matrix portion 14 of this example
Reference numeral 24 designates the column direction n and the side 24b facing the row direction m.
And 24d are parallel trapezoids. Therefore, the sides 24a and 24 that define the row direction m and face each other in the column direction n
c is tapered so as to narrow or widen in the row direction m, is not parallel to the row direction m, and is not orthogonal to the column direction n, which is the switching direction 83 of the micromirror 23. Therefore, the first-order diffracted light of the ineffective light diffracted by these sides 24a and 24c becomes the driving direction 8
The light is emitted in a direction different from the column direction n which is 3. Therefore, like the above-described optical switching device, the optical switching device of this example can also have the optical system arranged in the direction vertical or horizontal to the image, and the compact projector 1 can be configured.

Further, in the matrix portion 14 of the micro mirrors 24 of this example, the trapezoidal micro mirrors 24 are rotated 180 degrees for each row, so that they can be arranged densely in the row direction m without shifting by a half pitch. Has become.

(Fifth Embodiment) FIG. 6 is an enlarged view of a matrix section 15 of a different optical switching device 10 according to the present invention. The matrix portion 15 of this example is configured by a combination of a trapezoidal micro mirror 25 and a rectangle 26 whose four sides are non-parallel. Therefore, the trapezoidal micromirror 25 also has parallel sides 25a and 25c in the row direction m.
The sides 25a to 25d and 26a to 2 which are arranged to be inclined with respect to each other and which constitute the micromirrors 25 and 26.
6d is neither parallel to the row direction m nor the column direction n, and is not orthogonal to the row direction m or the column direction n.

Therefore, the micromirrors 25 and 2
6 switching direction 83 to column direction n or row direction m
However, there is no side orthogonal to these, and the first-order diffracted light of the ineffective light diffracted by those sides is emitted in a direction different from the driving direction 83. Therefore, like the above-described optical switching device, the optical switching device of this example can also have the optical system arranged in the direction vertical or horizontal to the image, and the compact projector 1 can be configured.

The trapezoidal micromirror 25 and the rectangular micromirror 26 having four non-parallel sides are complementary to each other, and two types of micromirrors 2 are provided.
By combining 5 and 26, the row direction m
It is possible to arrange densely without shifting by half pitch.

(Sixth Embodiment) FIG. 7 is an enlarged view of a matrix portion 17 of a different optical switching device 10 of the present invention. Each of the micro mirrors (reflection surface) 27 constituting the matrix portion 17 of this example is a parallelogram, and has two sides 27 that define the column direction n and face each other in the row direction m.
b and 27d are parallel to the column direction n, and the two sides 27a and 27c defining the row direction m and facing the column direction n are inclined with respect to the row direction m and are not orthogonal to the column direction n. Therefore, the first-order diffracted light of the ineffective light diffracted by these sides 27 a and 27 c is emitted in a direction different from the switching direction 83 (column direction n) which is the direction of the incident light 71 and the emitted light 72. Therefore, like the above-described optical switching device, the optical switching device of this example can also have the optical system arranged in the direction vertical or horizontal to the image, and the compact projector 1 can be configured.

Further, the micromirrors 27 of this example are arranged densely without changing the pitch in the column direction by changing the direction for each column in which the sides 27a and 27c facing in the row direction m are inclined in parallel. . It is also possible to arrange without changing the direction for each row, and in this case, the arrangement is shifted in the row direction.

(Seventh Embodiment) FIG. 8 is an enlarged view of a matrix portion 18 of a different optical switching device 10 of the present invention. Each of the micromirrors (reflection surface) 28 constituting the matrix portion 18 of this example has a rhombus shape so that all sides of the parallelogram are not parallel to the row direction m and the column direction n, and are not orthogonal. Arranged. Therefore, even if the row direction m or the column direction n is set as the switching direction 83, all the sides 28a to 28d are not orthogonal to the switching direction 83. Therefore,
The first-order diffracted light of the ineffective light diffracted by these sides 28 a to 28 d is emitted in a direction different from the switching direction 83. Therefore, also in the optical switching device of this example, the optical system can be arranged in the direction vertical or horizontal to the image, and the compact projector 1 can be configured.

Further, in the matrix portion 18 of this example, the diamond-shaped micromirrors 28 are arranged at a half pitch p in the row direction m, so that the micromirrors 28 are arranged densely. Further, the pitch pm in the row direction m and the pitch pn in the column direction n are set to the same size so that the image (pixel) displayed by each micro mirror 28 is not crushed.
For this reason, the micro mirror 28 has a rhombus shape that is flat in the column direction n.

(Eighth Embodiment) FIG. 9 is an enlarged view of a matrix portion 19 of a different optical switching device 10 of the present invention. The micro mirror (reflection surface) 29 that constitutes the matrix portion 19 of this example has four sides 29 a to 29.
d is formed by a curved line. Therefore, each side 29a-
29d is non-parallel to the row direction m and the column direction n, and is not orthogonal to the column direction n and the row direction m. Also in the matrix section 19 of this example, when the switching direction 83 is the row direction m or the column direction n, the first-order diffracted light diffracted by these sides 29a to 29d is the switching direction 83 and the column direction n. Is emitted in a direction different from. Therefore, the optical switching device 1 of this example
In the case of 0, the optical system can be arranged in the direction vertical or horizontal to the image, and the compact projector 1 can be configured.

Further, in the matrix section 19 of the present example, the micromirrors 29 are arranged by combining micromirrors of a plurality of types, so that the pitch p can be closely arranged in the row direction m and the column direction n without shifting. Has been placed,
It is an optical switching device with high light utilization efficiency (reflectance).

Instead of forming all sides with curved lines, linear sides and curved lines may be combined to form micromirrors, and it is also possible to combine them and arrange them in a dense manner.

Further, the optical switching device 10 described above is not limited to the projector shown in FIG. 1, but can be applied to a line printer (optical printer) 3 as shown in FIG. In this line printer 3, the semiconductor laser is used as the light source 61a, and the optical switching device 10 is provided on the optical path of the emitted light 71 output from the light source 61a.
Are arranged. Then, the luminous flux 72 modulated by the matrix portion of the optical switching device 10 is applied as print data to the photoconductor (photosensitive drum) 68 via the front lens 62a to form a latent image.
Based on this latent image, an image is printed on an appropriate sheet through toner (not shown) or a transfer device. The printer 3 that employs the optical switching device 10 has a high resolution,
It is possible to form a clear latent image having a large contrast, improve the printing speed, and provide the printer 3 with high printing quality.

Besides, the optical switching device of the present invention can be applied to a rear type projector suitable for a TV or a monitor and having a screen integrated therein.

[0051]

As described above, in the optical switching device of the present invention, the sides of the reflecting surface forming the matrix portion are not parallel to each other in the row direction or the column direction, so that the column direction or the row direction is formed. The incident light can be emitted from the. For this reason, it becomes possible to arrange a light source and a projection lens that form an optical system in the vertical or horizontal direction of the image, and a micro mirror device can be used to make a compact structure with a simple structure and a projector at a lower cost. It is possible to provide an image display device such as.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a projector type display device using an optical switching device according to the present invention.

FIG. 2 is a plan view schematically showing one example of the optical switching device according to the present invention shown in FIG.

FIG. 3 is a plan view showing a second embodiment of the optical switching device of the present invention.

FIG. 4 is a plan view showing a third embodiment of the optical switching device of the present invention.

FIG. 5 is a plan view showing a fourth embodiment of the optical switching device of the present invention.

FIG. 6 is a plan view showing a fifth embodiment of the optical switching device of the present invention.

FIG. 7 is a plan view showing a sixth embodiment of the optical switching device of the present invention.

FIG. 8 is a plan view showing a seventh embodiment of the optical switching device of the present invention.

FIG. 9 is a plan view showing an eighth embodiment of the optical switching device of the present invention.

FIG. 10 is a diagram showing an outline of a line printer using the optical switching device of the present invention.

FIG. 11 is a diagram showing an outline of a projector using a micromirror device.

FIG. 12 is a plan view showing the micromirror device used in FIG. 11.

FIG. 13 is a cross-sectional view explaining the operation of the micromirror device shown in FIG.

[Explanation of symbols]

1,90 Projector 3 line printer 10 Optical switching device 11-15, 17-19 Matrix part 20 Optical switching element 21-29 Micro mirror (reflection surface) 30 actuators 41 Control mechanism 71 incident light 72 reflected light 73 Diffracted light (ineffective light) 81 Incident direction 83 Drive direction (switching direction)

Claims (26)

[Claims] 1. An optical switching device comprising a matrix portion in which a plurality of optical switching elements for switching incident light by changing an angle of a reflection surface are arranged in at least one row or one column, wherein the matrix An optical switching device in which sides of the reflecting surface arranged so as to define a row-direction and / or column-direction arrangement of the parts are non-parallel to the row-direction and / or the column-direction. 2. The optical switching device according to claim 1, wherein the optical switching element drives the reflecting surface in the column direction or the row direction. 3. The optical switching device according to claim 1, wherein a side of the reflecting surface that defines the arrangement in the row and / or column direction is inclined with respect to the row and / or column. 4. The optical switching device according to claim 3, wherein the reflecting surface has a polygonal shape. 5. The optical switching device according to claim 4, wherein the reflecting surface has a hexagonal shape. 6. The optical switching device according to claim 4, wherein the reflecting surface is a trapezoid or a parallelogram. 7. The optical switching device according to claim 1, wherein a side of the reflecting surface that defines the arrangement in the row and / or column direction is a curve. 8. The optical switching device according to claim 1, wherein, of the sides of the reflecting surface, opposite sides have a complementary shape. 9. The optical switching device according to claim 1, wherein the reflection surface is arranged with a half pitch shift in the row direction and / or the column direction. 10. An optical switching device comprising a matrix section in which a plurality of optical switching elements for switching incident light by changing an angle of a reflecting surface are arranged in at least one row or one column. The switching element drives the reflecting surface in the column direction or the row direction, and the sides of the reflecting surface facing in the column direction or the row direction are
An optical switching device which is non-orthogonal to the column direction or the row direction. 11. The optical switching device according to claim 10, wherein the facing sides are inclined with respect to a direction orthogonal to the column direction or the row direction. 12. The optical switching device according to claim 11, wherein the reflecting surface has a polygonal shape. 13. The reflecting surface according to claim 12,
Optical switching device that is prismatic. 14. The optical switching device according to claim 13, wherein the reflecting surface is a trapezoid or a parallelogram. 15. The optical switching device according to claim 10, wherein the facing sides are curved lines. 16. The optical switching device according to claim 10, wherein the facing sides have complementary shapes. 17. The optical switching device according to claim 1, a light source device for irradiating the matrix portion of the optical switching device with incident light in the row direction or the column direction, and the optical switching device. And a lens system for projecting the modulated light reflected in the row direction or the column direction of the matrix part. 18. An image display device according to claim 17,
A projector type display device having a screen for displaying light output from the lens system. 19. An image display device according to claim 17,
A printer having a photoreceptor that forms a latent image by the modulated light. 20. A printer for forming a print image by the modulated light of the image display device according to claim 17. 21. An optical switching element for switching incident light by changing an angle of a reflecting surface, wherein the reflecting surface has a first set of sides facing in a first direction for driving the reflecting surface, and A second set of sides facing each other in a direction orthogonal to the first direction, the first set of sides being non-orthogonal to the first direction and having mutually complementary shapes; Optical switching elements whose sides are complementary to each other. 22. The optical switching element according to claim 21, wherein the sides of the first set are inclined with respect to a direction orthogonal to the first direction. 23. The reflecting surface according to claim 21,
Optical switching element that is polygonal. 24. The reflecting surface according to claim 23,
A hexagonal optical switching element. 25. The reflecting surface according to claim 23,
Optical switching element that is trapezoidal or parallelogram. 26. The optical switching element according to claim 21, wherein the first set of sides is a curve.