JP2001083601A - Projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a device with which the production cost of a spatial optical modulation element may be reduced and the dealing with higher fineness may be inexpensively embodied by providing the device with spatial optical modulation elements having spatial optical modulation elements which are arrayed to a line form in correspondence to plural pixels and modulate spectrally divided light by each line, thereby constituting the device. SOLUTION: The spatial optical modulation elements having the linear spatial optical modulation elements which are arrayed to the line form in correspondence to the plural pixels and modulate the spectrally divided light by each line are disposed by each of respective colors. The white light from the light source allows the transmission of the red color light by a dichroic mirror 101d and the blue light and green light are reflected and spectrally divided. The transmitted red light is modulated by the spatial optical modulation element 101a and the reflected blue and green light are spectrally divided by the dichroic mirror 101e, by which the blue light is transmitted and the green light is reflected. The transmitted blue light is reflected by a total reflection mirror 101f and is modulated by the spatial optical modulation element 101c. The costs of parts may be reduced by using a total reflection mirror, etc., for the mirror 101f.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a projector device, and more particularly, to a projector device which forms a display image by projection or light projection of a rear type projector or the like.

[0002]

2. Description of the Related Art A conventional example is disclosed in Japanese Patent No. 2,773,08.
No. 6 (hereinafter referred to as Conventional Example 1) discloses a liquid crystal projector in which a one-line video signal is transmitted through a linear liquid crystal panel to which an input signal is input, and the transmitted light is direction-controlled by a reflecting mirror and projected on a screen. ing. According to this conventional example 1, 2
A linear liquid crystal panel can cope with projection of a two-dimensional image.

As another conventional example, Japanese Patent No. 2,582
No. 0,104 (hereinafter referred to as Conventional Example 2) discloses that one of the S-polarized light component and the P-polarized light component obtained from the polarizing beam splitter is converted into the other polarized light by using a λ / 2 optical phase plate. A projection type display device using the combination of these as illumination light for a light valve is disclosed.

[0004]

However, in the above prior art example 1, the spatial light modulator is limited to a transmission type linear liquid crystal. Further, in the conventional example 2, only the light whose polarization is converted by the spatial light modulation element and the transmission type are described.

The present invention has been made in view of these problems, and an object of the present invention is to provide a projector device which can reduce the manufacturing cost of a spatial light modulator and can realize high definition at a low cost and easily. Aim.

[0006]

In order to solve the above-mentioned problems, a projector device according to the present invention comprises a spectroscopic means for optically dispersing white light from a light source, and a linear device corresponding to a plurality of pixels. And a spatial light modulator having a linear spatial light modulator having a linear spatial light modulator for modulating light separated by the spectral means line by line, and a spatial light modulator provided for each color, and modulated by the spatial light modulator. It has a polarizing means for deflecting each color light, and a projecting means for combining the deflected color lights and projecting them on a display panel. Therefore, the light is modulated by the spatial light modulator for each color light, the light use efficiency is improved, and a device with high illuminance can be realized.

A projector apparatus according to another aspect of the present invention provides an optical system unit for color-separating white light from a light source in a time-division manner, and modulates each color light color-separated by the optical system unit for each line, and It has a spatial light modulator having a linear spatial light modulator arranged in a line corresponding to a pixel, and a polarizing means for deflecting light modulated by the spatial light modulator and scanning the display panel. Therefore, the number of components can be reduced, the manufacturing cost of the spatial light modulator can be reduced, and a high definition can be easily and inexpensively realized.

Further, since the spatial light modulator has a plurality of linear spatial light modulators, a bright and high contrast ratio can be realized.

Further, a gray scale display can be realized by scanning a scanning line on a display panel a plurality of times with light modulated by each of the linear spatial light modulators.

Further, since the polarization angle in the polarization means is controlled by the electric signal, an image without distortion can be obtained.

[0011]

According to the projector device of the present invention, the optical system unit separates white light from a light source in a time-division manner. A spatial light modulator having a linear spatial light modulator arranged in a line corresponding to a plurality of pixels modulates each color light color-separated by the optical system unit for each line. The polarizing means deflects the light modulated by the spatial light modulator to scan and project the light on a display panel such as a screen or a liquid crystal.

[0012]

FIG. 1 is a schematic diagram showing the structure of a projector according to an embodiment of the present invention. In the figure, the projector device of the present embodiment includes optical system units 101 and 10.
5, light source 102, polygon mirror 103, projection lens 1
04 and the filter 106. According to the projector device of the present embodiment having such a configuration, the light from the light source 102 cuts an unnecessary wavelength range by the filter 106 and enters the optical unit 105. In the optical system unit 105, the light is converted into slit-shaped parallel light, and is incident on the optical system unit 101. This optical system unit 1
After being subjected to spectroscopy, modulation, and synthesis by 01, the light is deflected by the polygon mirror 103 and projected onto a screen (not shown) via the projection lens 104.

FIG. 2 is a schematic diagram showing the structure of the optical system unit 101 and the like in FIG. 1 as viewed from the side. In the figure, an optical system unit 101 splits light from a light source 102 using an optical member such as a dichroic mirror or a prism. For the sake of explanation, 101a is a red light, 1
01b is a spatial light modulator for modulating green light, and 101c is a spatial light modulator for modulating blue light. And the dichroic mirror 101d
Is a dichroic mirror 101e that transmits only red light.
Reflects only green light. Actually, the elements are linearly arranged in a direction perpendicular to the drawing. First, white light from a light source (not shown) is applied to a dichroic mirror 1.
01d transmits red light, and blue light and green light are reflected and separated. Dichroic mirror 101
The red light transmitted through d is modulated by the spatial light modulator 101a. The blue light and the green light reflected by the dichroic mirror 101d transmit the blue light and reflect the green light by the dichroic mirror 101e, and are separated. The blue light transmitted through the dichroic mirror 101e is reflected by the total reflection mirror 101f and modulated by the spatial light modulator 101c. Dichroic mirror 101
The green light reflected by e is modulated by the spatial light modulator 101b. The red light modulated by the spatial light modulator 101a is reflected by the total reflection mirror 101g, passes through the dichroic mirror 101h, and is reflected by the dichroic mirror 101i. The green light modulated by the spatial light modulator 101b is reflected by the dichroic mirror 101h and the dichroic mirror 101i. Further, the blue light modulated by the spatial light modulator 101c is a dichroic mirror 101i.
Through. Therefore, the light from the dichroic mirror 101i is light obtained by combining red light, green light, and blue light.

As described above, when a dichroic mirror or a prism that reflects only blue light is used for 101f, 1
The non-blue light reflected at 01d and transmitted at 101e is
Mixing in the image can be prevented, and the color purity is increased. When cost is important, the total cost of parts can be reduced by using a total reflection mirror or a prism for 101f. Similarly, by using a dichroic mirror or prism using a film that transmits only blue light to 101i, a film that reflects only green light to 101h, and a film that reflects total reflection or red light to 101g, as shown in FIG. Optical system can be realized. Also in this case, improvement of color purity can be realized by using a dichroic mirror or a prism for 101g, and cost reduction can be realized by using a total reflection mirror for 101g. The light that has been split immediately before the spatial light modulator and modulated and synthesized by the spatial light modulator is illuminated onto a screen (not shown) via a projection lens 104 by a deflecting unit such as a polygon mirror 103.

Here, an example in which a DMD (Digital Mirror Device) element developed by TI in the United States is used as the spatial light modulation element will be described with reference to FIG. However, FIG. 3 shows only the main components in the configuration. Actually, optical components such as lenses and mirrors (not shown) are required. In the figure, white light from a light source is divided into RGB by time division by a rotating color filter unit 202. Each divided light is reflected by a mirror 203 and two-dimensionally arranged DMD elements 201.
Irradiated to In the DMD element 201, the mirror angle of each pixel is modulated by the image signal, and the reflection angle of the irradiated light is modulated. Thus, the image is projected on the screen by making the reflected light of the pixel displayed brightly on the screen incident on the projection lens 204 and preventing the reflected light of the pixel darkened on the screen from entering the projection lens 204. According to the example using such a DMD element, as the resolution is increased, the degree of integration of the DMD element is increased, and the production cost is increased due to a decrease in yield. In other words, the higher the resolution, the higher the product cost had to be.

Therefore, the basic configuration of the present invention is to form an image by using a linear spatial light modulator and scanning the screen on a screen by means for deflecting the modulated reflected light. This will be described in detail below.

FIG. 4 is a schematic diagram showing the configuration of a spatial light modulator according to the present invention. In the figure, reference numeral 301 denotes a linear spatial light modulator, and 302 denotes a rotating color filter which divides white light from a light source into red light, green light, and blue light by time division. Reference numeral 303 denotes a rotating rectangular parallelepiped mirror which is an example of an element for deflecting light modulated by the spatial light modulation element onto a screen. In this example, a polygon mirror is used. Further, 304 is a projection lens, 30
Reference numeral 5 denotes an optical system unit which condenses the light time-divided by the color filter 302 in a slit shape and in parallel. In this embodiment, a line-shaped spatial light modulator is used by using the time-division color by the color filter 202 shown in FIG.
As a result, the colorization part uses the conventional technology described above, and reduces the cost of parts by using a spatial light modulation element, which is likely to be costly due to high definition, in a line shape. Costs can be kept low. Further, the white light is subjected to color separation using a dichroic film or the like, and at the same time, the separated light is modulated and recombined at least on a screen.

In the present invention, the light use efficiency is higher than that of the time division color. It is about three times theoretically. In time-division color, the light is always separated by a color filter, and only 1/3 of white light can be used at any one time. When using R, G,
B needs to be shielded from light. On the other hand, in FIG. 1, each color-separated light is individually modulated and combined at least on the screen, so that white light can reach the screen as it is at any moment. Actually, the loss due to transmission or reflection at the optical component is reduced, but the efficiency is high for time division.

Further, in the present invention, a spatial light modulating element for modulating light by using a mirror to reflect light and changing the angle of the mirror by an electric signal is used as the spatial light modulating element. DMD element commercialized by the above-mentioned TI Inc.,
This is the TMA being developed by Daewoo. In this system, the response speed is fast, and the light can be modulated with high efficiency and high reflectance of the mirror. However, the yield decreases as the number of pixels increases in the two-dimensional direction due to fine processing. The product cost will increase as the resolution increases. On the other hand, by using the line shape according to the present invention, a large number of modules can be obtained from the same wafer as the conventional technology,
Parts costs can be kept low.

Further, in the present invention, there is a liquid crystal material as a material for realizing an optical shutter of the spatial light modulator.
By using this liquid crystal, it can be realized at low cost.
In particular, by combining active matrix driving (TFT, MIM, etc.) with a ferroelectric liquid crystal as a material having memory properties, a response speed of several tens of μsec can be realized, and high image quality can be realized. Here, according to the present invention, the number of spatial light modulation elements is smaller than the number of pixels of the screen to be displayed by using the elements in a line shape, and the production can be performed at a higher yield and at a lower cost than the conventional technique.

Further, in the present invention, a linear spatial light modulator is used, and a plurality of spatial light modulators are used for each pixel on the screen. This point will be described with reference to FIG. In the figure, a spatial light modulation element 401, an optical system 402, and a pixel 403 on a screen are omitted from other components. The spatial light modulator 401 corresponds to one row on the screen in three rows. Numeral 402 in the figure schematically represents an optical member for condensing light modulated in three rows into one row on a screen for the sake of simplicity. Note that this does not limit the actual shape. As described above, in the present invention, since one line on the screen is represented by a plurality of rows, it is possible to easily modulate the screen illuminance of the corresponding pixel by independently modulating each row of the spatial light modulator. In general, a light-collecting system from a light source is more efficient when condensing light on a large area. Therefore, according to the present invention, by modulating the pixels on a small number of screens with the spatial light modulators in a plurality of rows, it is possible to easily perform gray scale display and increase the light use efficiency.

FIG. 6 is a schematic diagram showing an example in which a plurality of linear spatial light modulators of the present invention are used. The present invention considers a method of switching data on a line on a plurality of spatial light modulators and a light scanning direction on a screen, so that the same line on the screen can be sequentially changed a plurality of times from different linear spatial light modulators. Irradiate. This makes it possible to easily perform gradation display by modulating data for each irradiation. The principle of operation will be described below. In FIG. 6, from the rotation direction of the polygon mirror 503,
The light from the spatial light modulator 501 is scanned from top to bottom on the screen via the projection lens 504 to form one image. At this time, scanning line data is displayed on each of the linear spatial light modulation elements 501a to 501f on the spatial light modulation element 501 as shown in FIG. By this operation, when six linear spatial light modulators in FIG. 6 are used, each scanning line on the screen is scanned six times at different times within one frame period. By modulating the display contents (ON / OFF of each pixel) each time, it is possible to easily realize gray scale display. The present invention
In addition to scanning multiple times on the scanning line on the screen,
It does not place any restrictions. The direction of rotation of the mirror used in the description may be reversed. In this case, FIG.
In the configuration described above, the movement of the line data of each linear spatial light modulator is in the opposite direction. When an optical system such as a lens and a mirror not shown in FIG. 6 is used, the scanning direction on the screen and the data moving direction on the spatial light modulator may be opposite to those described above. In this case, the effect of the present invention can be obtained by determining the direction of data so that the same scanning line on the screen is scanned a plurality of times.

FIG. 7 is a diagram schematically showing data of each linear spatial light modulator and an irradiation position on a screen. For simplicity, means for deflecting the light after modulation by the spatial light modulator and optical members such as a projection lens are not shown. In the figure, reference numeral 501 denotes a spatial light modulator, and reference numeral 505 denotes a screen. The process proceeds from FIG. 7A to FIG. 7F. As in FIG. 6, the scanning direction on the screen 505 is from top to bottom. Referring to FIG.
5 is fixed, and the spatial light modulation element 501 is shown as falling from top to bottom. Actually, the element itself does not move, and the same effect can be obtained by an optical system for deflection. In FIG. 7A, the spatial light modulator 501f irradiates 505a corresponding to the first line on the screen. In FIG. 7B, 505a on the screen is the spatial light modulator 5
7e, the spatial light modulators 501a to 501f are sequentially different from each other in the period from FIG. 7 (a) to FIG. 7 (f). Irradiation. Similarly, the other lines on the screen are irradiated from six different spatial light modulators, and by performing modulation with the same pixel on the screen between these different irradiations, gradation display can be easily realized. It becomes possible. 7A to FIG. 7F are:
Depending on the number of irradiations from the spatial light modulator, the screen 50
5, 505a to 505f are color-coded from black to white. The display color is changed from black to white as the number of irradiations increases. As described above, according to the present invention, one image is formed on the screen by scanning the light modulated by the spatial light modulator on the screen. In the present invention,
As a means for deflecting light, a voltage or current or pulse control method is used.

FIG. 8 shows, as an example, a galvanometer mirror 703.
Here is an example using. In the figure, the spatial light modulator 7
The light modulated by 01 is deflected by a galvanometer mirror 703 and projected on a screen (not shown) via a projection lens 704. Although FIG. 1 assumes time-division color as an example, there is no limitation on the colorization method. The galvanomirror 703 can adjust the angular velocity by the current value input to the control unit. A uniform image can be obtained by modulating the angular velocity of the galvanomirror depending on where the scanning of the image on the screen starts, at the center and when the scanning ends.

FIG. 9 is an external view showing the configuration of a galvanomirror. In the figure, reference numeral 801 denotes a mirror, and 802 denotes a part for driving the mirror. As described above, when the mirror is controlled, the mirror has a function of detecting the mirror position, and by feeding back information of the detected position, the accuracy of drawing on the screen can be improved. As an example of the position detection method, a method in which a mark is formed on a polygon mirror and detection is performed using a reflective photointerrupter, or a method in which a mechanical shield is provided and detection is performed using a photointerrupter can be used.

FIG. 10 is a schematic view showing an example of a reflection type photo interrupter. In the same figure, a light emitting unit 901 and a light receiving unit 902 form a pair. For example, by marking an object to be detected so that light is absorbed, the light receiving unit normally reflects light from an object. Light is incident. When the mark passes, the light is absorbed, and the light is not incident on the light receiving unit, so that the light is electrically detected. FIG. 10A shows an undetected state, and FIG. 10B shows a detected state.

FIG. 11 is a schematic view showing an example of another photo interrupter. Normally, light from the light emitting unit 1001 is incident on the light receiving unit 1002. The shield 1004 is shown in FIG.
(B), the light receiving unit 1002 stops receiving light from the light emitting unit 1001 and detects this.
Detect at 3. By using the present invention, it is possible to obtain a high-brightness and high-image-quality projector capable of coping with high definition of a spatial light modulation element at low cost.

[0028]

As described above, according to the projector device of the present invention, the spectral means optically disperses white light from the light source. The spatial light modulation means in the present invention,
A spatial light modulating element having a linear spatial light modulating element which is arranged in a line corresponding to a plurality of pixels and modulates the light dispersed by the spectral means for each line is provided for each color. The respective color lights modulated by the respective spatial light modulators of the spatial light modulator are deflected by the polarizing means, combined with the respective color lights, and projected on the display panel by the projection means. Therefore, the light is modulated by the spatial light modulator for each color light, the light use efficiency is improved, and a device with high illuminance can be realized.

In another aspect of the projector according to the present invention, the optical system unit separates white light from the light source in a time-division manner. The spatial light modulator according to the present invention has a linear spatial light modulator arranged in a line corresponding to a plurality of pixels of light, and modulates each color light through the optical system unit for each line. The light modulated by the spatial light modulator is deflected by the polarizing means and scanned on the display panel. Therefore, according to the present invention having such a configuration, the number of components can be reduced, the manufacturing cost of the spatial light modulation element can be reduced, and high definition can be easily realized at low cost.

Further, since the spatial light modulator has a plurality of linear spatial light modulators, gradation display can be easily performed, and a bright and high contrast ratio can be realized.

Further, a gray scale display can be realized by scanning one scanning line on the display panel a plurality of times with light modulated by each of the linear spatial light modulators.

Further, since the polarization angle in the polarization means is controlled by an electric signal, an image without distortion can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a structure of a projector device according to one embodiment of the present invention.

FIG. 2 is a schematic diagram showing a structure of the optical system unit and the like in FIG. 1 as viewed from a side.

FIG. 3 is a schematic diagram illustrating an example in which a DMD element is used as a spatial light modulation element.

FIG. 4 is a schematic diagram illustrating a configuration of a spatial light modulator according to the present invention.

FIG. 5 is a schematic diagram showing an example in which a plurality of spatial light modulation elements are used corresponding to each pixel on a screen.

FIG. 6 is a schematic diagram showing an example in which a plurality of lines of a linear spatial light modulator in the present invention is used.

FIG. 7 is a diagram schematically showing data of each linear spatial light modulator and an irradiation position on a screen.

FIG. 8 is a schematic diagram showing an example using a galvanomirror.

FIG. 9 is an external view illustrating a configuration of a galvanomirror.

FIG. 10 is a schematic diagram showing an example of a reflection type photo interrupter.

FIG. 11 is a schematic diagram illustrating another example of a photointerrupter.

[Explanation of symbols]

101, 105: optical system unit, 102: light source 10
2, 103: polygon mirror, 104: projection lens, 1
06: Filter.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H088 EA12 EA37 HA10 HA11 HA13 HA18 HA21 HA24 HA28 MA03 MA16 2H091 FA26X FA41Z HA12 LA12 LA17 MA07

Claims (5)

[Claims] 1. A spectroscopic means for optically dispersing white light from a light source, and a linear space arranged in a line corresponding to a plurality of pixels, and modulating the light dispersed by the spectral means for each line. A spatial light modulator provided with a spatial light modulator having a light modulator for each color; a polarizing means for deflecting each color light modulated by the spatial light modulator; and a display panel combining the deflected color lights. And a projection device for projecting the image onto a projector. 2. An optical system unit for color-separating white light from a light source in a time-division manner, and modulating each color light color-separated by the optical system unit for each line to form a line corresponding to a plurality of pixels. A projector device comprising: a spatial light modulator having an array of linear spatial light modulators; and polarizing means for deflecting light modulated by the spatial light modulator and scanning the display panel. 3. The projector device according to claim 1, wherein the spatial light modulator has a plurality of linear spatial light modulators. 4. The projector according to claim 1, wherein one scanning line on the display panel is scanned a plurality of times by light modulated by each of the linear spatial light modulators. 5. The projector according to claim 1, wherein a polarization angle of the polarization unit is controlled by an electric signal.