JPH08146519A - Projector device - Google Patents

Abstract

PURPOSE: To make a projector device simple and compact, and raise the brightness of a display image to improve the utility of the device by detecting a light quantity from a beam transmitted through a variable shade means, and controlling the shade zone of the variable shade means on the basis of the detection result. CONSTITUTION: Regarding a projector device 40 to show a desired image on an image display screen, the effective reflected light of modulators 2R, 2G and 2B is imaged at a position immediately before a projector lens 11, so as to have a size smaller than the aperture of the projector lens 11, and variable shade means 41R, 41G and 41B are arranged at the imaging position of a light source 3 or in the neighborhood of the image via relay lens means 9R, 9G and 9B. Then, a luminous flux other than the effective reflected light is shaded and a light quantity is detected from a beam transmitted through the variable shade means 41R, 41G and 41B, using light control means 42R, 42G and 42B. Also, the shade zones of the variable shade means 41R, 41G and 41B are controlled on the basis of the detection result. Thus, the deterioration of contrast is prevented, and a color balance is easily adjusted without reducing a gradient number.

Description

Detailed Description of the Invention

[0001]

[Table of Contents] The present invention will be described in the following order. Field of Industrial Application Conventional Technology Problems to be Solved by the Invention Means for Solving the Problems (FIG. 6) Action (FIG. 6) Example (1) Overall Configuration of Projector Device (FIGS. 1 to 5) (2) ) Projector device of the embodiment (FIGS. 6 to 8) (3) Other embodiment Effect of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projector device, and is suitable for application to, for example, a device for projecting a color image.

[0003]

2. Description of the Related Art Conventionally, as a projector device of this type, there is a projector device which individually displays red, green and blue components of image data on three CRTs (cathode ray tubes).
On the front surface of this projection type three-tube projector device, three CRTs in which red, green, and blue color filters and projection lenses are sequentially arranged on the image projection surface side are arranged.

The CRT is designed so that the red, green and blue components of the image data are directly projected onto the screen separately at the time of projection, whereby the projected light of the red, green and blue components projected from each CRT on the screen is projected. One image is formed by combining them, and a color image is projected as a whole.

Further, instead of the projection type three-tube type projector device, there is a reflection type three-tube type projector device in which three CRTs are arranged inside the box. In the case of this projector device, an optical path similar to that of the projection-type three-tube projector device is reflected and bent by a mirror arranged inside the box, and projection light is irradiated from the back surface to a frosted glass-like semitransparent screen.

As a result, each CR is displayed on the screen.
The projection lights of the red, green, and blue components emitted from T are combined to form one image, and a color image is projected as a whole. In the case of this reflection type three-tube type projector device, by bending the optical path to reduce the size and integrally forming the screen itself, it is possible to realize a smaller size projector device than the projection type three-tube type projector device. The usability of can be improved.

[0007]

However, in the projection type three-tube projector device or the reflection type three-tube projector device having such a configuration, a CRT is used as a light source and an image projected from the CRT is enlarged and displayed on the screen. Therefore, there is a problem in that it is inevitable that the entire device becomes large, and it is difficult to increase the brightness of the display image.

In order to solve such a problem, three liquid crystal panel plates are used as an image source in place of the CRT, each of the liquid crystal panel plates displays red, green and blue components, and one surface of the liquid crystal panel plate is displayed. There is a so-called liquid crystal projector device which irradiates light from the side and forms an image of the transmitted light on a screen through red, green and blue color filters, respectively.

In the case of this liquid crystal projector device, the entire device can be remarkably miniaturized as compared with a projector device which uses a CRT because a liquid crystal panel is used, but the liquid crystal panel plate itself has a low light transmittance and displays a display image. In terms of achieving high brightness, it has not been practically sufficient.

By the way, as a display system, a minute mirror surface element is arranged in a plane according to a pixel, and a mirror surface deflection type optical modulator utilizing the reflection of each mirror surface element (hereinafter referred to as a mirror light valve) is used. Those have been proposed (JP-A-60-179781, JP-A-3-40693, and JP-A-3-174112).

If a projector device for magnifying and projecting a color image can be formed by using this mirror light valve as an image source, the overall structure of the device can be simplified to the same scale as the liquid crystal projector device and downsized,
Further, it is considered that the display image can be significantly increased in brightness by improving the utilization efficiency of the light source as compared with the liquid crystal.

The present invention has been made in view of the above points, and it is an object of the present invention to propose a projector device which can be simply and miniaturized and which can enhance the brightness of a displayed image and remarkably improve its usefulness.

[0013]

In order to solve such a problem, according to the present invention, an optical modulator (2R, 2G, 2R, 2G, etc.) having a plurality of optical modulators arranged corresponding to pixels of video data is provided.
2B) is irradiated with illumination light, and the light modulators (2R, 2R,
G, 2B) is modulated by image data, and the effective reflected light of the optical modulator (2R, 2G, 2B) according to the image data,
In the projector device (40) for displaying a desired image on the image display surface, the effective reflected light of the light modulator (2R, 2G, 2B) is placed just before the projection lens (11) from the opening of the projection lens (11). Relay lens means (9R, 9G, 9B) for forming a small image, and relay lens means (9
R, 9G, 9B) are arranged at or near the image forming position of the light source (3) by the light source (3), and the variable light shielding means (41R, 41G, 41B) for shielding light beams other than the effective reflected light, and the variable light shielding means (41R, 41G, 41B), and detects the amount of light from the light flux that passes through the variable light-shielding means (41R, 41R,
41G, 41B) light control means (4) for controlling the light-shielding region
2R, 42G, 42B).

[0014]

The light modulator (2R, 2G, 2B) having a plurality of light modulators arranged according to the pixels of the image data is irradiated with illumination light, and the light modulator (2R, 2G, 2B) is imaged. In the projector device (40) that displays a desired image on the image display surface by the effective reflected light of the optical modulator (2R, 2G, 2B) that is modulated by the data, the optical modulator (2R , 2G, 2B) through the relay lens means (9R, 9G, 9B) at a position immediately in front of the projection lens (11) with an image smaller than the aperture of the projection lens (11). Means (9R, 9G,
9B) variable light blocking means (41R, 41G, 41B) is arranged at or near the image forming position of the light source (3) to block light beams other than the effective reflected light, and the light control means (42R, 42G,
42B), the variable light blocking means (41R, 41G, 4
1B) detects the amount of light from the light flux that passes through 1B) and controls the light-shielding region of the variable light-shielding means (41R, 41G, 41B) based on the detection result, thereby preventing a decrease in contrast and reducing the number of gradations. The color balance can be easily adjusted without the need.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

(1) Overall Configuration of Projector Device In FIG. 1, reference numeral 1 indicates three mirror light valves 2 corresponding to respective image data of red, green and blue as a whole.
1 shows a projector device using R, 2G, 2B. 2 and 3 in which parts corresponding to those in FIG.
As shown in FIG. 3, the projection light L1 emitted from the high-intensity white light source 3 is converted into parallel light through a condenser lens 4 while unnecessary UV rays are removed by a UV filter (not shown). The dichroic mirrors 6R and 6 for separation while being bent by the reflection mirror 5 of No. 1
It is incident on G and 6B.

Separation dichroic mirrors 6R, 6G,
6B is a procession light L2 consisting of white light in red,
The green and blue lights LR, LG and LB are separated. This red,
The green and blue lights LR, LG, LB are obliquely bent upward by the second reflecting mirrors 8R, 8G, 8B through the beam shaping cylindrical lenses 7R, 7G, 7B, respectively, and reflected by the mirror light valves 2R, 2G, 2B. The surface is illuminated.

The mirror light valves 2R, 2G and 2B are
According to the pixel array of video data (for example, 768 x 576 pixels), a plurality of minute mirror surface elements each having a size of, for example, 17 [μm] square are arrayed, and thereby, a half
A reflective surface having a size similar to that of an inch CCD (solid-state image sensor) is formed. The micro mirror surface element is arranged corresponding to each memory cell of the frame memory according to the array of pixels of the video data, and the tilt state of the corresponding micro mirror surface element is changed individually according to the state of each memory cell. Has been done.

Practically, each micro mirror element tilts by + 10 ° as shown in FIG. 4 (A) when the memory cell is in the on state, that is, effective as a pixel with respect to the neutral state, and conversely, when the memory cell is in the off state, When it is invalid as a pixel, it is tilted by −10 ° as shown in FIG.
As a result, the reflected light reflected by the mirror surface with respect to the incident light is
It is switched so as to have an optical path difference of 20 ° between the effective reflected light necessary for forming an image and the invalid reflected light which is not effective.

In the case of this projector device 1, the image data for one frame of red, green, and blue is set in the frame memories corresponding to the mirror light valves 2R, 2G, and 2B, respectively, so that the effective reflected light is obtained. Red,
Green and blue image lights are formed. The red, green and blue image lights are respectively associated with relay lenses 9R, 9G and 9B.
Through dichroic mirrors for synthesis 10R, 10G,
It is guided to 10B and is combined as a color image light, and this is enlarged and projected through a projection lens 11 having a zoom lens structure onto a screen (not shown) arranged outside the projector device 1 at a distance.

In the case of the projector device 1, the high-brightness white light source 3, the condenser lens 4, the first reflecting mirror 5, the separating dichroic mirrors 6R to 6B, and the cylindrical lenses 7R to 7B are passed through the second reflecting mirror 8R. ~
The optical axis of the optical system of the projection lights L1 and L2 reaching 8B, the relay lenses 9R to 9B reflected by the mirror light valves 2R to 2B, and the dichroic mirror for synthesis 10R.
˜10B, the optical axis of the effective reflected light reaching the projection lens 11 is displaced by a predetermined height, thereby preventing interference between the projection light and the effective reflected light and the invalid reflected light. It is designed to get you.

Furthermore, in the projector device 1, the beam shape of the projection light is shaped by the cylindrical lenses 7R to 7B, whereby the second reflecting mirror 8 is formed.
Even if the light is reflected obliquely upward by R to 8B, the reflecting surfaces of the mirror light valves 2R to 2B can be illuminated with a uniform illuminance.

Here, in the projector device 1, the optical device shown in FIG.
The circuit portion shown in FIG. 5 in which the same reference numerals are assigned to the corresponding portions is provided. In this projector device 1, as a video signal to be displayed, a video signal S1 input as an RGB signal from a video device or a V signal from a personal computer or the like is used.
The video signal S2 sent corresponding to GA (video graphics arrey) and the video signal S3 of VGA pattern can be selected.

These video signals S1, S2, S3 are
Each of them is input to the video select circuit 21 and selected, and the resulting video signal S4 is converted into a digital video signal S5 by the analog-digital conversion circuit 22,
It is input to the gamma correction circuit 23. The test pattern signal S6 generated by the test pattern generation circuit 24 is input to the gamma correction circuit 23 as needed. As a result, the gamma correction circuit 23 performs gamma correction on the digital video signal S5 or the test pattern signal S6 according to the set gamma correction parameter S7, and sends the resulting digital video signal S8 to the reformatting circuit 25.

The re-format circuit 25 inputs the RGB video signal S1 and the VGA video signals S2 and S.
The digital video signal S8 corresponding to 3 is, for example, mirror light valves 2R to 2B composed of 768 pixels × 576 lines.
The digital video signal S9 of red, green, and blue components obtained by performing re-formatting according to the arrangement of the mirror surface elements
R, S9B and S9G are sent to the corresponding frame memories 26R, 26G and 26B, respectively.

The frame memories 26R to 26B correspond to the mirror light valves 2R to 2B, respectively, and in accordance with the control signal S10 input from the timing control circuit 27, the frame memories 26R to 2 are sequentially frame by frame.
The contents of 6B are written in the mirror light valves 2R to 2B, whereby red, green and blue image lights are formed as effective reflected lights.

In the case of this projector device 1, the timing control circuit 27 uses the input video signals S1 to S3.
Using the system clock S12 generated by the clock generation circuit 28 in accordance with the phase control signal S11 based on the above, the frame memories 26R to 26B and the mirror light valve 2R are used.
The control signal S10 for controlling .about.2B is generated.

Further, in the projector device 1, when the power switch (not shown) is turned on, the AC power S13 is supplied to the power supply circuit 30 and the lamp drive circuit 31. Of these, the power supply circuit 30 supplies a predetermined DC power S14 to each circuit section to start the operation of the projector device 1. Further, the lamp drive circuit 31 drives the high-intensity white light source 3 to be turned on, so that the white light source 3 emits the projection light L1.

According to the configuration of the projector device 1,
Mirror light valves 2R, 2G, and 2B corresponding to red, green, and blue are used as image sources, and the mirror light valves 2R to 2B are driven by red, green, and blue video signals, respectively, and white light is emitted. By irradiating red, green, and blue projection lights separated by color, and synthesizing the effective reflected light, and enlarging and projecting, compared with the conventional projector using a CRT. Projector device 1 with significantly smaller size, lighter weight and simple structure
Can be realized.

Further, since the mirror light valves 2R-2B are designed to reflect the projection light,
As compared with the liquid crystal projector device, the utilization efficiency of light can be remarkably improved, and thus it is possible to realize the projector device which can be reduced in size and weight and which can increase the brightness of the displayed image.

(2) Projector device of the embodiment In FIG. 6 in which parts corresponding to those in FIG.
0 indicates the projector device of this embodiment as a whole.
In the projector device 40, the mirror light valve 2
The effective reflected light reflected by R to 2B is imaged in the space immediately before the projection lens 11 by the relay lenses 9R to 9B, respectively. Further, a part of the light flux is blocked by the light blocking diaphragms 41R to 41B to limit the transmission of the light flux. A real image of the mirror light valves 2R to 2B is obtained only by the light flux transmitted through the light blocking diaphragms 41R to 41B, and the image is projected on the screen through the projection lens 11.

FIG. 7 shows the states of effective reflected light and ineffective reflected light on the mirror surface element. Mirror light valve 2R-2
The mirror surface element of B changes the tilt angle of each mirror surface according to the ON state or the OFF state of the memory cell, and irradiates a light beam from these mirror surfaces at an oblique angle. The light is incident on the projection lens via 9B. At this time, the invalid reflected light is not incident on the relay lenses 9R to 9B and the projection lens 11, but a part of scattered light and diffracted light generated from the mirror surface element in the off state is generated on the relay lenses 9R to 9B. It is incident on the projection lens 11.

Therefore, as shown in FIG. 8, the light-shielding diaphragm 41 is located at the position of the image forming point of the light source formed between the relay lenses 9R to 9B and the projection lens 11 or in the vicinity of the image forming point.
R to 41B are provided. At this time, the irradiation angle of a part of the light flux reflected by the mirror element in the off state changes due to scattering or diffraction, but this scattered light or diffracted light is applied to the light blocking diaphragms 41R to 41B. The light is blocked (broken line in the figure). Therefore, since the light flux incident on the projection lens 11 does not include an extra light flux and is only effective reflected light, it is possible to prevent the contrast from being lowered.

The light-shielding diaphragms 41R to 41B are controlled by photosensors 42R to 42B made of photodiodes. The optical sensors 42R to 42B are arranged on the side opposite to the irradiation surface of the combining dichroic mirrors 10R to 10B, and the light fluxes emitted from the mirror light valves 2R to 2B to the combining dichroic mirrors 10R to 10B are detected. The light quantity of the transmitted light flux is detected by the change in voltage. Convert the detection result obtained at this time into an electrical signal,
The amount of light transmitted through the light blocking stops 41R to 41B is adjusted by arbitrarily changing the light blocking areas of the light blocking stops 41R to 41B in accordance with this signal. As described above, since the color balance is optically achieved instead of the video signal, the color balance can be easily adjusted without reducing the number of gradations.

The relay lenses 9R to 9B in the projector device 40 are movable between the mirror light valves 2R to 2B and the combining dichroic mirrors 10R to 10B, so that the size at the image forming point should be changed. You can At this time, the projection lens 11 and / or the mirror light valves 2R to 2R depending on the size at the image forming point.
By changing the arrangement of B, the projected image on the screen can be made variable without changing the focal length of the projection lens 11, that is, the zooming function can be provided.

According to the above configuration, the projector device 4
Between the relay lenses 9R to 9B of 0 and the dichroic mirrors 10R to 10B for synthesis, light blocking diaphragms 41R to 41B for blocking invalid reflected light are arranged at a position where the image forming point of the light source is obtained or in the vicinity of the image forming point. By providing such a structure, it is possible to prevent a decrease in contrast. Moreover, by controlling the light-shielding diaphragms 41R to 41B by the optical sensors 42R to 42B, the color balance can be easily adjusted without reducing the number of gradations. Further, the relay lenses 9R to 9B are made movable, and the projection lens 1 according to the relay lenses 9R to 9B.
The zooming function can be obtained by changing the arrangement of 1 and / or the mirror light valves 2R to 2B.

(3) Other Embodiments In the above-described embodiments, the mirror-deflecting optical modulator is used as a mirror-deflecting optical modulator according to the arrangement of pixels of image data on the reflecting surface.
The case where an array of 768 × 576 micro mirror surface elements is used has been described, but the array of micro mirror surface elements is not limited to this, and various selections may be made. Even when microscopic mirror elements are arranged one-dimensionally and an image is formed by scanning the projection light, the same effect as that of the above-described embodiment can be realized.

Further, in the above-mentioned embodiment, the specular deflection type optical modulators driven according to the red, green and blue images are irradiated with red, green and blue projection light, respectively, and their effective reflection is performed. Although the case where light is combined and enlarged is described, instead of this, a single specular deflection type optical modulator is sequentially driven in time division according to red, green and blue images,
In synchronization with this, a projector that combines the projection of red, green, and blue projection light in a time-sequential manner, and a projector that combines two or more colors with a single mirror-deflecting light modulator Even when applied to a device or the like, the same effect as that of the above-described embodiment can be realized.

[0039]

As described above, according to the present invention, the invalid reflected light is shielded between the relay lens means and the projection lens of the projector device at the position where the image forming point of the light source is obtained or in the vicinity of the image forming point. By providing a variable light-shielding means and controlling the variable light-shielding means by a light control means, it is possible to prevent a decrease in contrast and easily adjust a color balance without reducing the number of gradations. realizable.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing the overall configuration of a projector device using a mirror-polarized light modulator.

FIG. 2 is a schematic plan view for explaining an optical system of the projector device of FIG.

3 is a schematic rear view for explaining an optical system of the projector device of FIG. 1. FIG.

FIG. 4 is a schematic diagram for explaining the operation of the mirror surface element of the mirror surface deflection type optical modulator.

5 is a block diagram showing a circuit configuration of the projector device of FIG. 1. FIG.

FIG. 6 is a schematic plan view showing the configuration of the projector device of the embodiment.

FIG. 7 is a schematic diagram for explaining effective reflected light and ineffective reflected light by a mirror surface element of a mirror surface deflection type optical modulator.

FIG. 8 is a schematic diagram used to explain a light-shielding diaphragm.

[Explanation of symbols]

1, 40 ... Projector device, 2 ... Mirror light valve, 3 ... High-intensity white light source, 4 ... Condenser lens, 5 ... First reflection mirror, 6 ... Separation dichroic mirror, 7 ... Beam shaping cylindrical lens, 8 ... second reflecting mirror, 9 ... relay lens, 1
0 ... Dichroic mirror for composition, 11 ... Projection lens, 21 ... Video select circuit, 22 ...
... analog-digital conversion circuit, 23 ... gamma correction circuit, 24 ... test pattern generation circuit, 25 ... refinance circuit, 26 ... frame memory, 27 ... timing control circuit, 28 ... clock generation circuit, 30 ...
Power supply circuit, 31 ... Lamp drive circuit, 41 ... Shading diaphragm, 42 ... Optical sensor.

Front page continuation (72) Inventor Nobuyuki Hara 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Sony Corporation

Claims (3)

[Claims] 1. An optical modulator having a plurality of optical modulators arranged corresponding to pixels of image data is irradiated with illumination light, and the optical modulator is modulated by the image data to obtain the image data. In the projector device that displays a desired image on the image display surface with the effective reflected light of the optical modulator according to the above, the effective reflected light of the optical modulator is located immediately before the projection lens, from the opening of the projection lens. A relay lens means for forming an image with a small image, a variable light-shielding means disposed at or near the image-forming position of the light source by the relay lens means for shielding a light beam other than the effective reflected light, and a variable light-shielding means. And a light control means for controlling the light blocking area of the variable light blocking means based on the detection result. 2. The relay lens means is arranged at an arbitrary position of an optical path on which the effective reflected light from the optical modulator is irradiated, and the optical modulation is arranged according to a position where the relay lens means is arranged. The projector device according to claim 1, wherein the position of the container and / or the projection lens is shifted. 3. The projector device according to claim 1, wherein the light modulation element is a specular deflection type spatial light modulation element that reflects incident light.