JP2000105362A - Color image display system, image display device and light irradiation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color display system high in the availability of a pixel display element without causing any loss of light. SOLUTION: As shown in c), white light 1 containing each color of RBG is separated into each color of light, and three adjacent image display elements 3 each are irradiated with RGB light of each different color respectively and the light of those colors are periodically changed over to each other or replaced with each other. Since a single pixel display element 3 is periodically irradiated with each of the RGB colors, the single pixel can be displayed in color with a single pixel display element 3. Since the other pixel display elements 3 are irradiated with the light of the other two colors, the loss of light is not caused. Further, since adjacent pixels display an image in different colors, color blurring is not caused at the time of reproducing a dynamic picture. In this way the small and bright image display device permitting capable of achieving high- resolution multi-color display can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device such as a liquid crystal projector and a light irradiation device suitable for the same, and more particularly to an image display device and a light irradiation device suitable for displaying a color image.

[0002]

2. Description of the Related Art In a conventional color image display device, the following two methods are known as methods for reproducing multicolor. In the first display method, a white light source is time-divided into three primary colors by a rotating filter or the like, and the time-divided light is modulated by one pixel display element to display one pixel. In the second display method, a white light source is separated into three primary colors, and a total of three pixel display elements are prepared for each color to display one pixel. In this,
One image display device is provided for each color light beam,
A device in which images formed by a total of three image display devices are synthesized by illuminating a screen or the like, or a color filter of three primary colors is provided for each pixel display element, and one pixel is formed by three pixel display elements. Includes what is displayed. A liquid crystal device, a micro mirror device, or the like is used as a pixel display element.

[0003]

According to these methods,
Although multi-color images can be displayed, some problems remain to be solved. First, a white light source is separated into three primary colors, and one pixel is displayed by associating a total of three pixel display elements with each color.
Although there is no light loss and good utilization efficiency, it is necessary to use as many as three expensive image display elements to display one pixel, which is expensive. Further, since three pixel display elements are required to display one pixel, it is necessary to further increase the element density of the pixel display device in order to cope with high-resolution image display, which is technically and economically solved. The problem to be solved remains. By providing three image display devices and combining them, a high-resolution image can be handled. However, three image display devices are required, and the size and cost of the device are increased when an optical system is included. Further, if a slight shift occurs during the synthesis, a color shift occurs, resulting in an image that is difficult to see.

On the other hand, in the above-described first method in which a white light source is color-separated into three primary colors by a rotary filter or the like in a time-division manner and one pixel is displayed by one pixel display element, only one pixel display element is required. The image display device can be miniaturized and can be realized at low cost. However, since the white light source is time-divided into three, two-thirds of the light cannot always be used, and the light use efficiency is poor. Therefore, a high-luminance light source is required to display a bright image, which is costly and power consumption is high. Further, when the display frequency to be time-divided is low, when the moving image is reproduced, the time-divided colors are sequentially displayed along the trajectory to form an afterimage, so that there is a problem that a color shift is observed.

Accordingly, an object of the present invention is to provide a color image display system in which one pixel can be displayed in full color by one pixel display unit or pixel display means and light loss is small. It is another object of the present invention to provide a color image display method that does not cause color shift during reproduction of a moving image when color display of one pixel is performed in one image display unit. It is another object of the present invention to provide an image display device using this color image display method and a light irradiation device suitable for the image display device.

[0006]

For this reason, in the present invention, different colors of light are radiated to adjacent pixel units.
We propose a color image display system that performs color display by periodically exchanging the colors. In this color image display method, when a gray scale display or the like is performed in adjacent pixel units, for example, in one pixel display element or a group of a plurality of pixel display elements, a different color is applied to the pixel display means. Light is illuminated and the colors are periodically exchanged. Accordingly, full-color (multi-color) display of one pixel can be performed in one pixel unit. Further, since light of different colors is irradiated on adjacent pixel units, light of a plurality of colors is simultaneously used for image display. Therefore, even when a plurality of colors of light separated from white light are used, a plurality of colors of light can be used for image display at the same time, so that the light use efficiency can be improved. Further, since light of different colors is irradiated to adjacent pixel units, the locus is grayed out when displaying a moving image. Therefore,
It is possible to prevent the color shift from remaining. At least one-dimensional direction,
That is, by irradiating light of a different color for each pixel adjacent to at least one of the scanning line direction and the sub-scanning direction and either the X or Y direction, a color shift in moving image display due to an afterimage is provided. Can be almost eliminated. In addition, since color display of one pixel can be performed in one pixel unit, a color image can be displayed with high quality without any color shift in a still image.

In the color image display system of the present invention, the number of pixel units to be periodically replaced does not necessarily have to match the number of colors to be irradiated. For example, by irradiating light of three primary colors to two pixel units while exchanging them, the light use efficiency can be increased from １ ／ to の of the conventional light use efficiency. Alternatively, the color tone of an image can be changed by irradiating light of four or more colors including an intermediate color to three pixel units while exchanging them. However, by irradiating a plurality of colors of light to adjacent pixel units of the number of colors periodically and irradiating the same, the plurality of colors of light separated from the white light are always used for color display. Can be used. Therefore, there is no light of a color that is not used for color display, and light loss can be prevented.

FIG. 1 shows the display system of the present invention in comparison with the above two display systems. FIG. 1A schematically shows the above-described first method, in which a white light 1 including red R, green G and blue B light is filtered by a filter 2.
, Red R, green G and blue B
The light of each color (hereinafter referred to as RGB) is sequentially irradiated to the pixel display element 3 such as a liquid crystal. In this method, one pixel can be displayed in color by one pixel display element 3 by controlling the gradation of light of each color of RGB sequentially supplied by the pixel display element 3. However, since the light of each color of RGB is supplied in order with a time interval, the light of the other two colors is always absorbed or reflected by the filter 2. Therefore, 2/3 of the white light 1 is always lost, and the light use efficiency is low.

FIG. 1B schematically shows the above-mentioned second method. White light 1 containing each of RGB colors is supplied to the pixel display element 3 as it is. Therefore, there is no light loss due to the filter, and the light use efficiency is high. However, since each pixel display element 3 controls the gradation of any one of RGB, three pixel display elements 3 are required to display one pixel in color. Therefore, the utilization efficiency of the pixel display element 3 is low, and the size of an image display device that displays images of the same density becomes large.

FIG. 1 (c) shows a color display system of the present invention, in which white light 1 containing each color of RGB is separated into light of each color, and each of three adjacent pixel display elements 3
Light of three different colors of RGB is emitted, and light of each color of RGB is exchanged or exchanged periodically. Since one pixel display element 3 is periodically irradiated with light of each color of RGB, one pixel display element 3 can perform color display of one pixel in the same manner as in the first method. On the other hand, the other two colors of light are applied to the other pixel display elements 3, so that no light loss occurs. Therefore, the color display method of the present invention can be used for the light use efficiency and the pixel display element (means).
It is possible to provide an image display device that is small, bright, and capable of high-resolution multi-color display.

To prevent light loss, there is a method of displaying one-third of the screen with each light separated into three primary colors and shifting the display in order. In this method, the effect of the afterimage is eliminated. It is difficult to prevent a color shift when displaying a moving image or a still image.

To realize the color display system of the present invention,
As shown in FIG. 1C, a light irradiating device 5 is required which can periodically irradiate a plurality of colors of light to each of a plurality of adjacent pixel display means. When using white light as a light source, a light irradiation device capable of irradiating a plurality of colors of light obtained by decomposing the white light to the adjacent pixel display means by periodically exchanging the light of each color is used. Required.

In order to irradiate a plurality of colors of light to different pixel display means and to exchange them, it is desirable to spatially separate the plurality of colors of light. Can be adopted at different predetermined emission angles, and a light supply unit that periodically exchanges the emission angle or color of each light beam can be employed. Then, it is possible to irradiate the pixel display means of the number of the separated colors by using the light condensing means for condensing light beams having different angles.

A micro lens array is preferable as the light condensing means, and a lens in which a spherical lens or a cylindrical lens is arranged in an array can be employed, and light fluxes of different colors are condensed on at least one pixel display means adjacent thereto in one direction. can do. The light supply means may emit light beams having different angles so as to overlap in the direction of the microlens array. In order to perform multi-color display, light beams of three primary colors are emitted by the light supply means, and the microlens array has a spherical surface or a cylindrical surface arranged to correspond to three or three rows of pixel display means. Microlenses may be arranged in an array.

Of course, not only the three primary colors but also intermediate colors can be used separately. In the above first conventional method, when the number of colors is increased, the light use efficiency is reduced in inverse proportion to the number of colors, and in the second method, the light necessary for displaying pixels is required. It increases in proportion to the number of colors of the pixel display means and becomes large. On the other hand, in the color display method of the present invention, even if the number of colors to be separated is increased, the light use efficiency does not decrease or the use efficiency of the pixel display means does not decrease. Therefore, the number of colors to be separated depending on the display purpose or the number of colors used for color display can be freely selected.

When white light is used as a light source, the white light is decomposed into light of a plurality of colors by a light supply unit, and a light beam of each color is emitted at a predetermined emission angle different for each color. It is desirable to periodically change the emission angle of the light beam. To periodically change the emission angle of the light beam, the light supply means includes a first optical element group including a plurality of mirrors or prisms capable of separating white light into a light beam of a predetermined color; In addition to the second optical element group having a plurality of mirrors or prisms whose directions can be changed, a third optical element group such as a mirror or prism for changing the emission angle may be provided. However,
By providing a mechanism for periodically changing the angle or position of the mirror or prism of the first or second optical element group, the number of optical elements can be reduced. When a plurality of mirrors or prisms capable of separating a light beam of a predetermined color from white light and changing the direction of the separated light beam are used, a mechanism for periodically changing the angle or position of these mirrors or prisms Can be provided.

Further, instead of exchanging the emission angle of the light beam, the color of the light beam may be exchanged periodically. To this end, the light supply means may be provided with a plurality of rotating dichroic mirrors capable of separating a plurality of colors from white light and reflecting the white light in a predetermined direction, so that the reflecting angles of the respective rotating dichroic mirrors are different. it can.

Of course, the light supply means may be provided with a light source such as a laser or an LED which can emit a plurality of colors.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 2 shows a schematic configuration of an optical color image display device (hereinafter, a display device) according to the present invention. In each of the following drawings, a light beam is represented by a central ray. The display device 10 of the present embodiment forms a white light source 11, a light irradiating unit 30 that can separate white light W from the white light source 11 into RGB colors and irradiate the image display unit 20 at a predetermined angle. For this purpose, an image display unit 20 in which pixel display elements are arranged in a two-dimensional array and a projection lens 12 that projects light L emitted from the image display unit 20 onto a screen 9 are provided.
The light irradiating unit 30 converts the white light W converted from the light source 11 into a substantially parallel light beam by the concave mirror 13 into red R, green G, and blue B light.
A light supply unit 39 for decomposing the light into the light beams of the respective colors and emitting the light in the direction of the image display unit 20; Have. The light supply unit 39 of the present example includes a white light W
First optical element group 3 that separates and reflects light into RGB light
1 and a second optical element group 32 that supplies the light of each color of RGB obtained from the first optical element group 31 to the image display unit 20 in a uniform manner.

The first optical element group 31 reflects the red R light from the white light W and transmits the other, and the first dichroic mirror 33 reflects the green G light and transmits the other light. A second dichroic mirror 34 and a mirror 35 that reflects the remaining blue B light are arranged in this order from the light source 11 side. Further, the second optical element group 32 includes:
The mirrors 36, 3 adjusted to an appropriate angle so that the RGB light reflected from the mirrors 33, 34, and 35 of the first optical element group 31 are reflected toward the image display unit 20.
7 and 38 are provided. In the second optical element group 32 as well, dichroic mirrors that reflect light of a predetermined color and transmit light of other colors are used for the mirrors 37 and 38, and are separated by the first optical element group 31. The light beams of the respective colors are combined by the second optical element group 32 so as to substantially overlap again, and are emitted toward the image display unit 20.

The mirrors 33 and 34 of the first optical element group 31
And 35, each of which can be controlled to three angles. When the mirror 33 reaches the first angle A1, the red light R is reflected by the mirror 36 of the second optical element group 32, and the image display unit 20 Is supplied as a light beam φ1 having a first emission angle. Further, the mirror 33 is moved to the second angle A2.
, The red light R becomes the light flux φ2 of the second emission angle, and when it becomes the third angle A3, the light flux φ3 of the third emission angle
And supplied to the image display unit 20. Mirror 34 that reflects green G light and mirror 3 that reflects blue B light
5 is also the same.

The light irradiation section 30 further includes an angle control mechanism 40 for controlling the angles of the mirrors 33, 34 and 35 of the first optical element group 31. This angle control mechanism 40
Are mirrors 33, 3 at a fixed period (display frequency).
Control is performed using electromagnetic force, electrostatic force or electrostrictive force so that the angles of 4 and 35 are changed to A1, A2 and A3. Examples of such a rotatable mirror include a galvanometer mirror and a step mirror. By using a similar mechanism, the angles of the dichroic mirrors 33, 34, and 35 can be controlled in this example as well.
In this example, the mirrors 33, 34, and 35 are further controlled so as to have different angles (angles having different phases). For example, the mirror 33 has an angle A1, the mirror 34 has an angle A2, and the mirror 35 has an angle A3. It is controlled so that FIG. 2 shows the timing at which the angles of the mirrors 33, 34 and 35 are set as described above. As a result, the light flux of the red R separated from the white light W becomes the light flux φ1 of the first emission angle. Is supplied to the image display unit 20. On the other hand, the green G light flux becomes the light flux φ2 at the second emission angle, and the blue B light flux becomes the light flux φ3 at the third emission angle.
Thus, the light is supplied toward the microlens array 50 installed on the front surface of the image display unit 20.

Further, at the next timing of the display frequency, the mirror 33 moves the mirror 33 to the angle A2,
The mirror 34 is cyclically controlled to the angle A3, and the mirror 35 is cyclically controlled to the angle A1. FIG. 3A shows a state of the light emitted from the light irradiation unit 30 at this timing. The red R becomes the light flux φ2 at the second emission angle, and the green R
Is a light flux φ3 at the third emission angle, and blue B is a light flux φ1 at the first emission angle and supplied toward the image display unit 20. At the next timing of the display frequency, the mirrors 33, 34 and 35 are controlled by the angle control mechanism 40.
Are changed to angles A3, A1 and A2, respectively. Accordingly, as shown in FIG. 3B, red R is a light flux φ3 at a third emission angle, green G is a light flux φ1 at a first emission angle, and blue B is a light flux at a second emission angle. φ2 is supplied to the image display unit 20. The light beams φ1, φ2, and φ3 supplied toward the image display unit 20 are condensed on each pixel display element by the microlens array 50 installed on the front surface of the image display unit 20.

FIG. 4 shows the vicinity of the image display section 20 in an enlarged manner. The image display unit 20 of the present embodiment includes a plurality of pixel display elements 21 arranged two-dimensionally in an array, and a transparent support plate 22 for supporting the pixel display elements 21 from an emission side (screen side).
And In the image display section 20 shown in FIG. 4, an example is shown in which a transmissive liquid crystal display element is used as the pixel display element 21, but the pixel display element 21 is not limited to a transmissive liquid crystal display element. , Reflective liquid crystal display element,
Furthermore, it is possible to use various pixel display elements that can control the gradation of light intensity, such as a microlens mirror device that modulates light by changing the reflection angle and an optical switching element that uses a micromachine such as an evanescent device. it can.

The image display section 20 of this embodiment is further provided with a microlens array 50 in which a plurality of microlenses 51 are arranged in an array in the light incident direction.
The microlens array 50 includes one microlens 51 having three pixel display elements 21a, 21b and 21.
The three light fluxes φ1, φ2, and φ3 having different irradiation angles with respect to c are respectively arranged so as to be condensed. For this purpose, the microlens 51 may be a spherical lens corresponding to three pixel display elements or a cylindrical lens corresponding to three rows of pixel display elements. In addition, 3 corresponding to one micro lens 51
One pixel display element 21a, 21b and 21c is irradiated with three light fluxes φ1, φ2 and φ3 having different irradiation angles, respectively. For this reason, the entrance or exit surfaces of the pixel display elements 21a, 21b and 21c are each inclined at a small angle so that the outgoing light obtained by gradation-controlling the light beams φ1, φ2 and φ3 becomes a parallel light beam. Such angle adjustment with respect to the emitted light can be performed using a micro prism or the like. In the case of a reflective pixel display element, the reflection direction of the element can be finely adjusted,
Of course, the angle adjustment of the outgoing light may be performed using a micro lens 51 different from the incident side of the micro lens array 50.

FIG. 5 shows how the light supplied from the light irradiating section 30 to the three pixel display elements 21a, 21b and 21c corresponding to one micro lens 51 changes. First, at the display frequency timing starting from time t1, the red R light beam is supplied as the light beam φ1 at the first irradiation angle, the green G light beam is supplied as the light beam φ2 at the second irradiation angle, as described above. , A blue B light beam is supplied as a light beam φ3 at the third irradiation angle. Therefore, these light beams φ1,
φ2 and φ3 are focused on the adjacent display elements 21a, 21b and 21c, respectively. Therefore, the display element 2
1a is irradiated with a red R light beam, the display element 21b is irradiated with a green G light beam, and further, the display element 21c is irradiated with a blue B light beam. That is, the adjacent display elements 21a, 21b and 21c are irradiated with light of different colors.

At the next timing starting from time t2,
The irradiation angle of the light beam of each color of RGB changes, the light beam φ1 of the first irradiation angle becomes blue R, the light beam φ2 of the second irradiation angle becomes red R, and the light beam φ3 of the third irradiation angle becomes green G.
Therefore, the adjacent display elements 21, 21b and 21c
Are changed, and the display elements 21, 21b and 21c are illuminated by light beams of blue B, red R and green G, respectively. Further, at the next timing starting from time t3, the irradiation angle of the light beam of each color of RGB changes again, the light beam φ1 of the first irradiation angle is green G, the light beam φ2 of the second irradiation angle is blue B, and the third light beam is blue B. The luminous flux φ3 at the irradiation angle becomes red R. Therefore, the display elements 21 and 21b
And 21c are further exchanged, and the display elements 21, 21b and 21c are illuminated by the light beams of green G, blue B and red R, respectively. Then, at the timing starting from the next time t4, the irradiation angle of the light beam of each color of RGB becomes the same as that at the time t1, so that the light beams irradiated on the adjacent display elements 21a, 21b and 21c are exchanged (replaced) again. Each display element 21
Each of a, 21b and 21c is irradiated with a light beam of the same color as that at time t1.

As described above, in the display device 10 according to the present embodiment, each pixel display element 21 of the image display section 20 is irradiated with the luminous flux of each color of RGB in order. Therefore, by controlling the luminous flux of these colors during the timing when the light of each color is irradiated, one pixel display element 2
1 allows one pixel to be displayed in full color. While the white light W is separated into the three primary colors and the luminous flux of one color is irradiated on one pixel display element 21, the luminous flux of another color is vertically or left and right. Is irradiated. Therefore, the light flux of the color obtained by separating the white light W is applied to any one of the pixel display elements 21 and is simultaneously used for forming a screen. Can be used for

Further, in the display device 10 of the present embodiment, there is no color shift when reproducing a moving image. FIG. 6 shows this state. As shown in FIG. 6A, in the case of a moving image in which a white display moves quickly on an image with a black background, a color image display apparatus using a rotating color filter or the like, which is the first conventional method described above. In (2), since the same color separated in time is sequentially displayed, each color is displayed with a shift as shown in FIG. In contrast, according to the present invention, adjacent pixels display different colors of RGB as shown in FIG. For this reason, the adjacent pixels do not have the same color. Even if the colors are sequentially displayed when the white color moves, the colors are juxtaposed and mixed from the viewing position as shown in FIG. Therefore, when a color image is displayed by using the image display device 10 of the present embodiment, no color shift occurs, so that fatigue when watching a movie or the like for a long time can be greatly reduced.

In the above description, the angles of the mirrors 33, 34, and 35 of the first optical element group 31 in the light supply section 39 for separating the white light W into light fluxes of RGB colors are controlled to control the image display section 20. The light beams φ1, φ2, and φ3 are formed by changing the emission angles of the light beams of the respective colors supplied to the light emitting devices. Instead, as shown in FIG. 7, the angles of the mirrors 36, 37, and 38 of the second optical element group 32 having the function of aligning the directions of the separated light beams toward the image display unit 20 are set. The light beams φ1, φ2, and φ3 are controlled by the angle control mechanism 40.
It is of course possible to form The configuration of the image display device 10 shown in FIG. 7 is the same as that of the image display device described with reference to FIG. 2 except that the mirror controlled by the angle control mechanism 40 is different. Description is omitted.

(Second Embodiment) Several configurations of the light irradiation unit 30 applicable to the image display device 10 according to the present invention can be considered in addition to the above. In the following, particularly, the light irradiation unit 30
Among them, some examples of the light supply unit 39 that irradiates the microlens array 50 with light beams φ1, φ2, and φ3 having different emission angles for each color will be described. In the following embodiments, since the image display unit 20 and the microlens array 50 are common, only the configuration of the light supply unit 39 will be described.

The light supply section 39 shown in FIG. 8 is a mirror 3 constituting a first optical element group 31 having a function of color separation.
The angles of both mirrors 36, 37, and 38 constituting a second optical element group 32 having a function of substantially aligning the respective light beams and directing the overall direction to the image display unit 20 are controlled. This is an example in which light beams having different colors are emitted as light beams φ1, φ2, and φ3 having different emission angles, and can be exchanged at the timing of the display frequency. Further, in the light supply unit 39 of this example, the mirrors 33, 34, 35, 36, 37, and 38 have two possible positions so that each mirror has two positions.
The value can be controlled.

For this reason, the mirrors 33, 34 and 35 constituting the first optical element group 31 of this embodiment can be set at two angles (positions H and L). Also, the mirrors 36, 37 and 38 constituting the second optical element group 32 can be set at two angles (positions H and L). Further, the angle control mechanism 40
A function is provided for individually setting the positions of 3, 34, 35, 36, 37 and 38 to H and L.

The positions L and H of these mirrors
Are selected as shown in FIG. In FIG. 9, mirrors 33 and 36 for controlling the light flux of red R are shown as an example. That is, when the mirror 33 is at the position H and the mirror 36 is at the position L, the light flux of the red R
Is supplied to the image display unit 20 as a light beam φ1 having an irradiation angle of. When the positions of the mirror 33 and the mirror 36 are both H or L, the luminous flux φ2 of the second irradiation angle
And the position of the mirror 33 is L
When the position of the mirror 36 is H, the light beam is supplied as the light beam φ3 at the third irradiation angle. Therefore, by controlling the two mirrors 33 and 36 in binary, the red R
Can be supplied as three light beams φ1, φ2 or φ3 having different irradiation angles. The other green G light beam and blue B light beam can be similarly controlled. Note that the positions H and L represent the case where the angle of the mirror is large and small with respect to the optical axis for the sake of convenience. It is only necessary that light beams having different irradiation angles can be obtained.

In FIG. 10, each mirror of the light supply section 39 of the present embodiment is controlled so that each pixel display element 21 is controlled as shown in FIG.
The manner in which the light beams a, 21b, and 21c are irradiated with the light beams of the respective colors RGB is shown using a timing chart. As shown in the figure, in the light supply unit 39 of the present example, the phase of the control signal supplied to each mirror is shifted in synchronization with the display frequency, so that the irradiation angle of the light beam of each color of RGB is changed and the image display unit is changed. The microlens array 50 can irradiate each pixel display element 21 while exchanging a light flux of each color.

(Third Embodiment) FIG. 11 shows an example of a light supply unit 39 different from the above. The light supply unit 39 of the present example combines the first optical element group 31 that separates and extracts the three primary colors from the white light W with the extracted luminous flux of each of the RGB colors and guides the luminous flux toward the image display unit 20. Optical element group 32
In addition to the above, a third optical element group 45 for controlling the emission angles of the light beams of the RGB colors is provided. For this reason, in the light supply unit 39 of the present example, the angles of the mirrors that constitute the first and second optical element groups 31 and 32 are kept constant, and the angle control mechanism 40 is configured by the third optical element group. By controlling the optical elements constituting 45, the light beams of each of the RGB colors are supplied as light beams φ1, φ2, and φ3 of the first, second, and third emission angles.

The third optical element group 45 of this embodiment includes a combination of optical elements 46 and 4 composed of two galvanometer mirrors that rotate at an appropriate angle or rotate at an appropriate cycle.
7 and 48 are prepared, and the direction of the luminous flux for each color can be controlled in each combination.

The light supply section 39 shown in FIG. 12 is an example in which a micromirror array 60 is employed as the third optical element group 45 for controlling the emission angle of the light flux of each color of RGB. The micro mirror array 60 includes a plurality of micro mirrors 6.
Numeral 1 is two-dimensionally arranged so that the reflection angle can be controlled using an electrostatic field or the like. In this example, a plurality of micro mirrors 61 are provided in three regions 62r,
The angle is controlled by being divided into regions of 62g and 62b, the emission angle of the red R light beam is controlled in the region 62r, and the emission angle of the green G light beam is controlled in the region 62g. The emission angle of the blue B light beam is controlled in the region 62b.

The light supply unit 39 shown in FIG. 13 is an example in which a prism is used as an optical element constituting a third optical element group 45 for controlling an emission angle. And in this example,
One set of wedge-shaped prisms 63a, 63b and 63c having three types of angles is formed, and a plurality of sets of prisms are formed into a belt-like shape 64 to be rotated at a constant period. RG supplied from the first optical element group 31 to the second optical element group 32
When the luminous flux of each of the B colors traverses at a constant speed, the angle of the luminous flux of each of the RGB colors that has passed through the prism belt 64 differs, and the angle changes cyclically. Therefore, from the second optical element group 32, the luminous fluxes of the RGB colors are converted into the luminous fluxes φ1, φ2 having the first, second, and third emission angles.
The light is emitted while being exchanged (exchanged) as any one of φ3 and φ3.

In order to control the emission angle by moving an optical element such as a belt, a sheet 66 having a large number of microprisms 65 whose diffraction direction changes periodically as shown in FIG. 14 is used. It is also possible to realize.

As described above, a wide variety of optical elements can be employed as the third optical element group 45. Similarly,
Not only in this example, but also in the above-described examples and the examples described below, the optical elements constituting the first and second optical element groups 31 and 32 are not limited to mirrors or dichroic mirrors. Various optical elements that select a predetermined color and reflect or transmit light can be adopted. Further, it goes without saying that other light sources such as a white laser can be used as the white light source 11 in addition to the white lamp as described above.

(Fourth Embodiment) The light supply unit 39 shown in FIG. 15 has a function of extracting the luminous flux of each of the RGB colors from the white light W, and a function of synthesizing them and guiding them toward the image display unit 20. Further, the function of controlling the emission angle of each color of RGB is realized by one optical element. For this reason, in this example, the angles of the three dichroic mirrors 71, 72 and 73 installed close to each other are set to 3 by the combination of the cam 74 and the motor 75.
It can be switched between stages. Then, the motor 75 is controlled by the control mechanism 40.

FIG. 16 shows a mirror 73 which is located at the third position and processes the blue B light flux. The mirror 73 turns around a turning center 77, and the operating portion 78 of the mirror 73 is always in contact with the cam 74 by a spring 76. The cam 74 is provided with a portion 74a for increasing the angle of the mirror 73, a portion 74c for reducing the angle, and a portion 74b for maintaining the angle therebetween. Therefore, this cam 74 is connected to the motor 75
By rotating the mirror 73, the angle of the mirror 73 can be controlled.
The angles of the other mirrors 71 and 72 can be controlled by the same configuration, and these three mirrors 71 and 72 can be controlled.
And 73 are changed synchronously with the display frequency, and RGB
The luminous fluxes of the respective colors are converted into luminous fluxes φ of first, second and third emission angles.
Light is emitted while being exchanged as 1, φ2 and φ3.

(Fifth Embodiment) FIG. 17 shows an example of a light supply unit 39 different from the above. In the above example, R
The light beams φ1, φ2, and φ3 having different emission angles are obtained by changing the emission angles of the light beams of the respective colors GB in order. In the present embodiment, the light beams φ1, φ having different emission angles are provided.
By exchanging the colors 2 and φ3 in order, the pixel display element 2 of the image display unit 20 is
The light flux of each color can be periodically exchanged and irradiated for one. For this reason, the light supply unit 39 of the present example
Is that the first rotating dichroic mirror 81, the second rotating dichroic mirror 82, and the mirror 83
Are arranged in order in the optical path of The first and second rotating dichroic mirrors 81 and 82 are shown in FIG.
As shown in (b) and (b), the disk-shaped dichroic mirror is divided into three regions R, G, and B that reflect each of the three primary colors and can transmit other colors. The first and second rotating dichroic mirrors 81 and 82 are adapted to rotate in synchronization with the display frequency by the control mechanism 40.
The phases of the colors to be reflected are shifted, so that different colors are reflected from the first and second rotating dichroic mirrors 81 and 82. The light of the color transmitted through the first and second rotating dichroic mirrors 81 and 82 is reflected by the mirror 83.

The first rotating dichroic mirror 8
The first and second rotating dichroic mirrors 82 and the fixed mirror 83 are adjusted so as to be able to reflect light beams toward the image display unit 20 at slightly different angles. Therefore, for example, the first rotating dichroic mirror 81 emits a light beam φ3 having a third emission angle, and the second rotating dichroic mirror 82 emits a light beam φ2 having a second emission angle. The light beam φ1 having the first emission angle is emitted from the mirror 83 of the expression. Then, as the first and second rotating dichroic mirrors 81 and 82 rotate synchronously, the light fluxes φ3, φ2, and φ1 are sequentially switched (exchanged) to red R, green G, and blue B light fluxes. Therefore, as shown in FIG. 4, the microlens array 50 located on the front surface of the image display unit 20 has different colors, the colors are switched in order, and the three light beams φ1, φ2, and φ3 is irradiated. For this reason, the corresponding 3
The two pixels 21a, 21b and 21c are irradiated with light of different colors while being switched in synchronization with the display frequency. Therefore, by using the light irradiation unit 30 including the light supply unit 39 of the present example, the light use efficiency is high as in the image display device described in the above embodiment, and the use efficiency of the pixel display element is also high. Image display device with a high cost can be realized.

In the light supply section 39 shown in FIG. 19, a first rotating dichroic mirror 81, a second rotating dichroic mirror 82 and a fixed mirror 83 are arranged close to each other. Can be configured to
The light irradiation unit 30 can be reduced to a small size. Further, even if the first and second rotating dichroic mirrors 81 and 82 and the fixed mirror 83 are arranged close to each other, the light of the color reflected by each mirror passes through the other mirror. Therefore, it is possible to combine in a predetermined direction. In addition, since the reflected positions are close to each other, it is easy to combine the light beams φ1, φ2, and φ3 having slightly different irradiation angles, and it is easy to design the optical path.

The light supply unit 39 shown in FIG.
This is an example in which the function as the first and second rotating dichroic mirrors is realized by one optical element 85. The optical element 85 is a conical prism, and can be rotated around a central axis in synchronization with a display frequency.
The bottom surface 85a and the side surface 85b are divided into regions for selecting and reflecting each of the RGB colors by shifting the phase in the same manner as shown in FIGS. 18A and 18B. Therefore, by rotating the optical element 85, FIG.
As in the case of the light supply unit shown in FIG. 5, a light beam obtained by combining three light beams φ1, φ2, and φ3 having different irradiation angles is obtained, and the colors of the light beams φ1, φ2, and φ3 are exchanged in synchronization with the display frequency. Become like

The light supply unit 39 shown in FIG. 21 does not have a fixed mirror for reflecting light of colors transmitted through the first and second rotating dichroic mirrors 81 and 82. Therefore, the light fluxes extracted and reflected by the first and second rotating dichroic mirrors 81 and 82 are reflected by the first and second fixed mirrors 86 and 87, and the first and second rotating dichroic mirrors 81 and 82 The light is transmitted to the image display unit 20 by being combined with the light flux transmitted through the light source 82.

(Sixth Embodiment) In the image display device 10 shown in FIG. 22, a light source section 90 using lasers 91, 92 and 93 of RGB colors is provided in a light supply section 39. Therefore, the light supply unit 39 of this example does not require an optical element for color separation. For this reason, in this example, the RG emitted from each of the lasers 91, 92 and 93
The angles of the mirrors 36, 37, and 38 of the second optical element group 32 to be synthesized by changing the direction of the light flux of each color B are controlled to supply light fluxes φ1, φ2, and φ3 having different emission angles. Of course, the light source unit 39 is not limited to a laser, and a light emitting element such as an LED can be used.

In the above description, the projection device using the image display device according to the present invention is described as an example. However, the present invention is not limited to the projection device, and may be an image display device for directly viewing a color image. The present invention can be applied to all devices that perform color display.

[0052]

As described above, in the color image display system of the present invention, adjacent pixels are illuminated with different colors of light and the colors are periodically exchanged. In particular, when using a light beam obtained by dividing white into RGB, the same number of adjacent pixel display units are irradiated with the light beam of each color and the colors are exchanged periodically. Therefore, all light obtained by dividing white into RGB can always be used for image display, so that light loss is small. Further, since one pixel display means is irradiated with all colors, multi-color display of one pixel is possible with one pixel display means. Therefore, since the number of pixel display means may be small, the image display device can be made inexpensive and small. Further, since it is not necessary to increase the number of pixel display means for color display, the yield is improved, and high resolution or high density can be easily achieved.

Further, a high quality color image can be displayed without bleeding due to pixel shift as in the case where a plurality of pixel display means are used to display one pixel. Furthermore, since an image is formed while adjacent pixels display different colors,
There is no effect due to afterimages, and there is no color shift during video playback.
Therefore, an image that is easy on the eyes can be displayed.

As described above, the color image display system of the present invention and the image display apparatus using the same can solve the drawbacks of the conventional color display system at a stretch, and can also use various color display means. It can be applied to an image display device. Therefore, the present invention is useful not only in a projector but also in a device that displays various color images.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams for explaining a display system of the present invention in comparison with other conventional display systems. FIGS. 1A and 1B show a conventional system, and FIG. Are schematically shown.

FIG. 2 is a diagram illustrating an outline of the image display device according to the first embodiment;

FIG. 3 is a diagram illustrating an operation of a light supply unit in the image display device shown in FIG.

FIG. 4 is an enlarged view showing a configuration of an image display unit and its vicinity in the image display device shown in FIG. 2;

FIG. 5 is a diagram showing a state in which the color of a light beam applied to each pixel display element changes according to the display method of the present invention.

FIG. 6 is a diagram showing a state in which color misregistration does not occur by the display method of the present invention.

FIG. 7 is a diagram illustrating a different example of the image display device according to the first embodiment;

FIG. 8 is a diagram illustrating a configuration of a light supply unit in the image display device according to the second embodiment.

FIG. 9 is a diagram illustrating a control method of the light supply unit shown in FIG.

FIG. 10 is a diagram illustrating control for irradiating each pixel display element with a light beam having a different color in the image display device including the light supply unit shown in FIG.

FIG. 11 is a diagram illustrating a configuration of a light supply unit in an image display device according to a third embodiment.

FIG. 12 is a diagram illustrating another example of the light supply unit according to the third embodiment.

FIG. 13 is a diagram showing still another example of the light supply unit according to the third embodiment.

14 is a diagram illustrating an example of a prism sheet that can be used in the light supply unit illustrated in FIG.

FIG. 15 is a diagram illustrating a configuration of a light supply unit in an image display device according to a fourth embodiment.

16 is an enlarged view of the cam shown in FIG.

FIG. 17 is a diagram illustrating a configuration of a light supply unit in an image display device according to a fifth embodiment.

FIG. 18 is a diagram showing an outline of a rotating dichroic mirror shown in FIG. 17;

FIG. 19 is a diagram illustrating a different example of the light supply unit according to the fourth embodiment;

FIG. 20 is a diagram illustrating still another example of the light supply unit according to the fourth embodiment;

FIG. 21 is a diagram showing still another example of the light supply unit according to the fourth embodiment.

FIG. 22 is a diagram illustrating an outline of an image display device according to a fifth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 White light 2 Filter for color separation 3 Pixel display means 5 Light irradiation means 10 Image display device 11 Light source 12 Projection lens 20 Image display section 21 Pixel display element 30 Light irradiation section 31 First optical element group 32 Second optics Element group 33-38 Mirror 39 Light supply unit 40 Control mechanism 45 Third optical element group 50 Micro lens array 51 Micro lens 60 Micro mirror array 61 Micro mirror 64 Prism belt 71-73 Mirror 74 Cam for mirror drive 75 Motor 81 , 82 Rotating dichroic mirror 83, 86, 87 Fixed mirror 85 Conical dichroic prism 90 Light source 91, 92, 93 Laser

Continued on the front page F-term (reference) 2H088 EA14 HA13 HA21 HA23 HA25 HA28 MA03 MA06 MA20 2H093 NC49 ND08 ND17 ND20 ND34 ND42 ND53 NE06 NG02 5C006 AA01 AA02 AA11 AA22 AF52 AF85 BB11 EA01 EC11 FA41 FA51 A54 BB15A56 FA00 BB17 CC12 DD02 DD05 EE18 FF03 GG01 GG03 GG04 GG08 GG10 GG28 GG46 LL15

Claims (17)

[Claims] 1. A color image display method for irradiating adjacent pixels with light of different colors and periodically exchanging the colors to perform color display. 2. A color image display system according to claim 1, wherein light of a plurality of colors is periodically exchanged and irradiated to adjacent pixel units of the number of colors. 3. A light irradiation device which irradiates light of a different color to adjacent pixel display means and can exchange the color periodically. 4. The light irradiation device according to claim 3, wherein the light of a plurality of colors can be periodically exchanged and irradiated to the adjacent pixel display means of the number of colors. 5. A light irradiation device according to claim 4, wherein the light irradiation device can separate white light into light of a plurality of colors and irradiate the light. 6. A light supply unit according to claim 3, wherein said light supply means emits a plurality of color light beams at different predetermined emission angles and periodically exchanges the emission angle or color of each light beam, and said adjacent pixel display. A light irradiating device comprising: a light condensing means for condensing the light beams having different angles with respect to the means. 7. The light irradiation apparatus according to claim 6, wherein the light condensing means is a microlens array, and the light supply means emits the light beams so as to overlap in the direction of the microlens array. 8. The light source according to claim 6, wherein
A light irradiation device for emitting a light beam of a primary color, wherein the microlens array includes microlenses arranged so as to correspond to three or three rows of the pixel display means. 9. The light source according to claim 6, wherein:
Light irradiation characterized by decomposing white light into light of a plurality of colors, emitting light beams of each color at predetermined emission angles different for each color, and periodically exchanging the emission angles of those light beams. apparatus. 10. The first optical element group comprising a plurality of mirrors or prisms capable of separating white light into a light beam of a predetermined color, and a direction of the separated light beam. And a third optical element group including a plurality of mirrors or prisms capable of periodically changing the direction of the separated light beam. A light irradiation device, comprising: 11. The light source according to claim 9, wherein the light supply means includes a first optical element group including a plurality of mirrors or prisms capable of separating white light into a light of a predetermined color, and a direction of the separated light. A second optical element group including a plurality of mirrors or prisms capable of changing the angle, and a mechanism for periodically changing the angle or position of the mirror or prism of the first or second optical element group. A light irradiation device, characterized in that: 12. A plurality of mirrors or prisms according to claim 9, wherein said light supply means separates a light beam of a predetermined color from white light and can change the direction of the separated light beam, and these mirrors or prisms And a mechanism for periodically changing the angle or position of the light irradiation device. 13. The light supply device according to claim 6, wherein the light supply unit separates the white light into light of a plurality of colors, emits the light of each color at a different predetermined emission angle, and changes the color of the light. A light irradiation device characterized by periodic replacement. 14. The light supply means according to claim 13, wherein said light supply means comprises a plurality of rotating dichroic mirrors capable of separating a plurality of colors from white light and reflecting in a predetermined direction. A light irradiation device characterized by different angles. 15. The light irradiation device according to claim 6, wherein the light supply means includes light sources of a plurality of colors. 16. An image display device using the color image display system according to claim 1. 17. An image display device comprising: the light irradiation device according to claim 3; and a plurality of the pixel display means arranged in an array.