JP2695712B2 - Display system control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a spatial light modulator,
The present invention relates to a display system that displays a video signal as a visible video on a screen, and a control method thereof.

[0002]

2. Description of the Related Art As a display system for displaying a video signal as a visible video, a display system using a CRT or a liquid crystal is generally used. The display system has been required to have a larger screen size. However, in a display system using a CRT or a liquid crystal, it is impossible to manufacture a display system having a very large screen size in terms of cost and structure.

Therefore, recently, a display system having a larger screen size than that using a CRT or a liquid crystal has been realized by using a spatial light modulator.

FIG. 6 is a schematic configuration diagram showing a conventional example of a display system using the spatial light modulator (see Japanese Patent Application Laid-Open No. 3-40693).

As shown in the figure, in this display system, a two-dimensional light modulator 52 formed by arranging a large number of light control elements 51 in a plane is disposed as a spatial light modulator. Each light control element 51 of the two-dimensional light modulator 52 is controlled by the electronic control unit 53, and reflects and deflects incident light in a specific direction.

As an optical system, a light source 54 and a concave mirror 55 are provided.
, Three condenser lenses 56, a plane mirror 57, and a projection lens 58, and a screen 59.

In the above configuration, the concave mirror 55 efficiently converts the light L-11 generated by the light source 54 into a condenser lens 56.
And the condenser lens 56 converts the light L-11 into a substantially parallel light flux L-12. The plane mirror 57 reflects the light beam L- 12 from the light source 54 and makes the light beam L- 12 enter the two-dimensional light modulator 52.

Each light control element 5 of the two-dimensional light modulator 52
1 individually deflects the incident light beam L-12 toward the projection lens 58 under the control of the electronic control unit 53. In other words, the two-dimensional light modulator 52 includes the individual light control elements 51
By deflecting the light beam L-12 at, the light beam L-
12 will be modulated. And the projection lens 58
The modulated light from the two-dimensional light modulator 52 composed of the deflection beam L-13 from the light control element 51 is imaged on the screen 59.

FIG. 7 is a block diagram showing the structure of the electronic control unit 53.

As shown in the figure, in this electronic control unit 53, T
An analog video signal from a signal source 61 such as a V tuner is converted into a digital code by an A / D (analog / digital) converter 71, and the digital code is stored in a buffer memory 72. This digital code represents the address and luminance of each pixel constituting the video. If the input video signal is a digital signal from a computer or the like, the digital video signal is sent directly to the buffer memory 72 and stored as a digital code.

Further, the digital code in the buffer memory 72 is decoded by the CPU 73 and stored in the video memory 74 as video data. In some cases, the video data is transmitted to the CPU 73 by the CPU 73.
After modification according to the program in 73 or an external command, it is stored in the video memory 74.

The video data in the video memory 74 is sent to each light control element 51 of the two-dimensional light modulator 52 via a shift register latch 75, and the two-dimensional light modulator 5
2, the light beam L-12 from the light source 54 is modulated.

According to the display system having the above structure, the electronic control unit 53 controls each light control element 51 of the two-dimensional light modulator 52 based on the video signal, and modulates the light beam L-12 from the light source 54. Accordingly, the image signal can be displayed as a visible image on the screen 59 so as to enlarge the shape of the two-dimensional light modulator 52 in an enlarged manner.

[0014]

However, the two-dimensional light modulator 52 used in the conventional display system has a very large number of light control elements 51 arranged in a plane. There is a high rate of defective elements that do not operate properly, and the yield is poor to obtain a complete two-dimensional optical modulator 52. For this reason, in the conventional display system, there is a problem that the unit cost of the two-dimensional light modulator 52 increases, the manufacturing cost of the system increases, and the reliability decreases.

Further, the electronic control unit 53 for controlling the large number of light control elements 51 of the two-dimensional light modulator 52 has a problem that its constituent circuits become complicated and the device itself becomes large. Also change the aspect ratio of the video
There was a problem that you can not. Furthermore, primary
Original light modulator and light that deflects the light modulated by the original light modulator
In the case of a device with a scanning device, bleeding between lines may occur.
As a result, there is a problem that image quality is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve these problems. An electronic control device for controlling a light control element of a spatial light modulator, which has a high reliability and a high image quality while reducing manufacturing costs. configuration circuit is simplified, the aspect
Aims to Ratio to provide a control method of the display system can be changed.

[0017]

In order to achieve the above object, a method for controlling a display system according to the present invention comprises:
As a spatial light modulator, a one-dimensional light modulator in which a plurality of light control elements are linearly arranged is arranged, and one-dimensional modulated light from the one-dimensional light modulator is deflected so that the primary Display system with an optical scanning device for scanning in the direction perpendicular to the longitudinal direction of the light modulator
In the control method of the stem, the one-dimensional optical modulator
The one-dimensional modulated light is converted into an image formed by the one-dimensional light modulator.
Intermittently image on the screen line by line
Caught .

Further, the scanning speed of the optical scanning device is changed.
I was able to make it .

[0019]

In the display system having the above-mentioned structure, the one-dimensional light modulator and the optical scanning device sequentially form an image based on the image signal line by line on a screen. Then, by making the vertical scanning time shorter than one cycle of the critical flicker frequency of the human eye, the image is perceived as one screen image from the afterimage effect of the human eye. Furthermore, within one line scanning period, the difference in the amount of light on the screen due to the difference in the operation time of each light control element can be recognized by the human eye as the difference in luminance of each pixel, that is, the gradation (contrast). It becomes possible. Therefore, with the configuration of the display system and the control method thereof, the video signal can be displayed on the screen as a two-dimensional visible video. In addition, one line of an image formed by the one-dimensional optical modulator is formed.
By forming an image on the screen intermittently every time
Blurring between lines can be reduced. Also light
By changing the scanning speed of the scanning device,
The aspect ratio can be changed.

[0020]

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

FIG. 1 is a schematic configuration diagram of a display system according to an embodiment of the present invention. As shown in the figure, the feature of this display system is that a one-dimensional light modulator 2 formed by linearly arranging a plurality of light control elements 1 is arranged as a spatial light modulator. Of the one-dimensional light modulator 2 on the screen 3
And an optical scanning device 4 for scanning in a direction perpendicular to the length direction of the optical scanning device.

As another structure, an electronic control unit 5 for controlling the light control element 1 of the one-dimensional light modulator 2 is provided, and a light source 6, a concave mirror 7, a three condenser lens 8, And a projection lens 9.

The one-dimensional light modulator 2 includes an electronic control unit 5
Each of the light control elements 1 controlled by the mirror is of a deformable mirror type that reflects and deflects incident light in a specific direction. This type of spatial light modulator is disclosed in U.S. Pat. Nos. 4,441,791; 4,710,732;
No. 96992, No. 4615595, No. 46627
Nos. 46 and 168724.

As shown in the perspective views of FIGS. 1 and 2, the optical scanning device 4 includes a plurality of reflection planes 10 of the same size.
And a rotating mirror 11 having
And a motor 13 that rotates around the motor 2. The rotating mirror 11 is arranged on the optical path between the one-dimensional light modulator 2 and the projection lens 9 with its axis 12 being parallel to the one-dimensional light modulator 2. In this embodiment,
The rotating mirror 11 forms a regular hexagonal prism, and has six reflecting planes 10.
It has. Regarding the shape of the rotating mirror 11,
Is not limited to the regular hexagonal prism, it may be a regular triangular prism having a reflecting plane 10 of the three-sided as shown in the perspective view of FIG. 3 (A), further
May be a regular polyhedral pillar having seven or more faces . Further, a columnar rotating prism can be used instead of the rotating mirror 11, in which case the light from the one-dimensional optical modulator 2 is deflected by refraction.

In the above configuration, the light L-
When the concave mirror 7 efficiently enters the condenser lens 8 into the condenser lens 8, the condenser lens 8 converts the light L-1 into a substantially parallel light flux L-2 and enters the one-dimensional light modulator 2.

Each light control element 1 of the one-dimensional light modulator 2 individually controls the incident light flux L-2 under the control of the electronic control unit 5.
In the direction of the rotating mirror 11 of the optical scanning device 4. That is, the one-dimensional light modulator 2 modulates the light beam L-2 by deflecting the light beam L-2 by the individual light control elements 1.

The rotating mirror 11 reflects the deflected beam L-3 from the light control element 1 on any one of the reflecting planes 10 and deflects it in the direction of the projection lens 9. Then, the projection lens 9 forms an image of the one-dimensional modulated light from the one-dimensional light modulator 2 composed of the deflection beam L-3 on the screen 3. At this time, the one-dimensional modulated light is linearly imaged on the screen 3 corresponding to the shape of the one-dimensional light modulator 2.

Further, when the motor 13 rotates the rotating mirror 11 in a fixed direction, the rotating mirror 11 changes the deflecting direction of the deflecting beam L-3 from the light control element 1, whereby
The one-dimensional modulated light from the one-dimensional light modulator 2 is
The upper part is scanned in a direction perpendicular to the length direction of the one-dimensional light modulator 2. In addition, the rotating mirror 11 has its reflection plane 1
Since the deflection beam L-3 is reflected one after another at 0, the one-dimensional modulated light repeatedly scans the screen 3 in a fixed direction corresponding to the rotation direction of the rotating mirror 11.

FIG. 4 is a block diagram showing the configuration of the electronic control unit 5.

As shown in the figure, the electronic control unit 5 has an A / D
(Analog / digital) converter 21, buffer memory 22, CPU 23, S / P (serial / parallel) converter 24, shift register latch 25
And a pulse width generator 26. Note that the pulse width generator 26 can be incorporated in the CPU 23.

In the electronic control unit 5, an analog video signal from a signal source 31 such as a TV tuner is converted into a digital code by an A / D converter 21, and the digital code is stored in a buffer memory 22. This digital code represents the address and luminance of each pixel constituting the video. If the input video signal is a digital signal from a computer or the like, the digital video signal is sent directly to the buffer memory 22 and stored as a digital code.

Next, the digital code in the buffer memory 22 is decoded by the CPU 23 and sent to the S / P converter 24 as video data. In some cases, the video data is transmitted to the CPU 23 by the CPU 2.
3 is sent to the S / P converter 24 after being modified in accordance with the program in 3 or an external command.

Subsequently, the video data from the CPU 23 is
/ P converter 24 divides each address,
The divided data is sent to the shift register latch 25 via the bus 27. The shift register latch 25
When the data of the address corresponding to one line of the video is ready, the data of the one line is sent to the pulse width generator 26 in accordance with the synchronization signal from the CPU 23, and the data having the pulse width corresponding to the luminance of each address is transmitted. The signal is converted into a signal, and the data signal of each address is sent to each light control element 1 of the one-dimensional optical modulator 2 according to the synchronization signal. By this data signal, the operation time of each light control element 1, that is, the time for deflecting the light beam L-2 from the light source 6 toward the rotating mirror 11 of the optical scanning device 4 is controlled in accordance with the luminance of each pixel, The light beam L-2 from the light source 6 is modulated.

Then, the data signal for each line of the image is sent to the light control element 1 of the one-dimensional light modulator 2 to transmit the light beam L-
2 and at the same time, scanning by the optical scanning device 4 is performed.

Further, at this time, control is performed so that the scanning cycle of the optical scanning device 4 is shorter than the critical flicker frequency of the human eye, that is, one cycle of the maximum frequency at which the blinking of light can be recognized. By this control, each of the light control elements 1
The difference in the amount of light on the screen 3 due to the difference in the operation time can be recognized by the human eye as the difference in the luminance of each pixel, and an image without flicker can be displayed. Of course, the light control element 1 of the one-dimensional light modulator 2 can operate at a sufficient speed in response to such control. In the above description, each light control element 1 is
It corresponds to one pixel of the digitized video signal
However, the contrast ratio of each light control element 1 is further increased.
If you want to increase the operable time (when scanning one line)
Interval) is short, and the contrast is sufficient at the same operating speed.
If not, one pixel of the video signal is
It is conceivable to represent the element 1. In this case, each light control
If the size of the element is reduced, high definition and high contrast
You can get a video of the

That is, according to the configuration and control method of the display system, the one-dimensional light modulator 2 and the optical scanning device 4 sequentially form an image based on the image signal line by line, and furthermore, the scanning is performed once. By making the time shorter than one cycle of the critical flicker frequency of the human eye, the video signal is displayed large on the screen 3 as a two-dimensional visible video.

According to this display system, the one-dimensional light modulator 2 having a significantly smaller number of light control elements than the two-dimensional light modulator is used as the spatial light modulator. And the complete one-dimensional light modulator 2 having no defective light control element 1 can be obtained with a good yield, so that the cost of the spatial light modulator can be greatly reduced and the reliability can be reduced. Can also be improved.

The circuit configuration of the electronic control unit 5 for controlling the light control element 1 of the one-dimensional light modulator 2 can be greatly simplified as compared with the case of the two-dimensional light modulator. The cost and the size of the control device 5 can be reduced. The effect of cost reduction by the one-dimensional light modulator 2 and the electronic control unit 5 can be sufficiently obtained by adding the optical scanning device 4 having a simple configuration.

Next, as another embodiment of the present invention, a method for displaying a color image using the above display system will be described.

In order to color the display system, the one-dimensional modulated light from the one-dimensional light modulator 2 is filtered by filters respectively corresponding to three colors of red (R), green (G) and blue (B). What is necessary is just to add the wavelength selection means which transmits sequentially.

As the wavelength selecting means, for example, as shown in an explanatory view of FIG.
R, G, B optical filters RF, G
F, Fit the the BF in a certain order. Or optical filter RF as octopus, GF, in the case of using BF, the light source 6
A white light source such as a halogen bulb is used.

The electronic control unit 5 controls the signal source 31.
Is divided into R, G, and B signals for each screen based on the color information included in the video signal,
The light control element 1 of the one-dimensional light modulator 2 is controlled by the G and B signals as described above. The control is performed by the rotating mirror 11
By synchronizing the scanning with each of the reflection planes 10 and corresponding to the optical filters RF, GF, and BF of each color, a color image can be displayed on the screen 3. Also in this case, R, R
The time for presenting the three screens G and B is shorter than one cycle of the critical flicker frequency of the human eye.

In addition, the light source 6 is composed of three light sources such as LEDs that emit light of wavelengths corresponding to the three colors of R, G, and B, and the three color light sources are sequentially switched to emit light. Is also good. Even when such three-color light sources are used, a color image can be displayed as in the case where the optical filters RF, GF, and BF are used.

In the above-mentioned colorized or non-colored display system, the one-dimensional modulated light from the one-dimensional light modulator 2 is intermittently transmitted to the screen 3 for each line of the image formed by the one-dimensional light modulator 2. By controlling to form an image on the upper side, lines are more clearly separated from each other, and no bleeding occurs at the boundary between the lines. As a result, the image can be displayed more clearly on the screen 3. it can. In addition, no extra light is irradiated on the screen 3 during the retrace period from the last line to the first line.

In order to form an image of the one-dimensional modulated light intermittently in this manner, for example, the light emission of the light source 6 may be pulsed, or a high-speed shutter may be arranged in the optical path from the light source 6 to the screen 3. Alternatively, a stepping motor may be used as the motor 13 for rotating the rotating mirror 11 of the optical scanning device 4, and the rotating mirror 11 may be intermittently rotated for each scan of one line.

Further, in the above colorized or non-colored display system, by controlling the scanning speed of the optical scanning device 4 to be changed, that is, in the case of the above embodiment, the rotation speed of the rotating mirror 11 by the motor 13 is reduced. By changing the aspect ratio, the length of the image displayed on the screen 3 in the scanning direction can be changed, and the aspect ratio (aspect ratio) of the image can be easily and continuously changed. However, when the rotation speed of the rotating mirror 11 is increased to increase the length of the image in the scanning direction, the shape of the rotating mirror 11 and the size of the reflection plane 10 are appropriately designed according to the length. Need to be kept. In conventional display systems, this aspect ratio is determined by the arrangement of the light control elements of the two-dimensional light modulator.

[0047]

As described above, according to the display system and the control method thereof according to the present invention, an inexpensive one-dimensional light modulator and an optical scanning device are used to convert a video signal into a two-dimensional visible image on a screen. Can be displayed. As a result, the manufacturing cost of the display system using the spatial light modulator can be reduced, and the configuration circuit of the electronic control device for controlling the light control element of the spatial light modulator can be simplified and the electronic control device can be downsized. Can be.

[0048] Further, Ru can also be colorized by using a light source corresponding to the three colors of the wavelength selection means or red, green, and blue. By changing the scanning speed of the optical scanning device
The aspect ratio of the image to be displayed it is possible to change easily steplessly Ri. Also, each line of the video is interrupted.
Reduces bleeding between lines by imaging continuously
To improve the quality of the image.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a display system according to an embodiment of the present invention.

FIG. 2 is a perspective view of the optical scanning device according to the embodiment of the present invention.

FIGS. 3A and 3B are perspective views showing another example of a rotating mirror of the optical scanning device.

FIG. 4 is a block diagram illustrating a configuration of an electronic control device according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram of a wavelength switching unit in another embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a display system in a conventional example.

FIG. 7 is a block diagram illustrating a configuration of an electronic control device in a conventional example.

[Explanation of symbols]

 Reference Signs List 1 light control element 2 one-dimensional light modulator 3 screen 4 optical scanning device 5 electronic control device 6 light source 9 projection lens 11 rotating mirror (optical scanning device) 13 motor (optical scanning device) 31 signal source RF, GF, BF optical filter (Wavelength switching means)

Claims (5)

(57) [Claims] A spatial light modulator that modulates light from a light source with a light control element; an electronic control device that controls a light control element of the spatial light modulator based on a video signal from a signal source; and a projection lens for imaging the modulated light from the optical modulator onto a screen, the video signal displayed on the screen as a visible image, as the spatial light modulator, a linear multiple optical control device While arranging the one-dimensional light modulators arranged side by side and deflecting the one-dimensional modulation light from the one-dimensional light modulator, a direction perpendicular to the length direction of the one-dimensional light modulator on the screen. control de I spray system placing the optical scanning device for scanning
In our method, a one-dimensional modulated light from the one-dimensional light modulator above, the one-dimensional
Intermittently, each line of the image formed by the optical modulator
Display characterized by imaging on a clean screen
How to control the system . 2. The light from a light source is modulated by a light control element.
Based on the spatial light modulator and the video signal from the signal source.
Electronic control device for controlling the light control element of the spatial light modulator
And the modulated light from the spatial light modulator on the screen.
And a projection lens for projecting the image signal into a visible image.
Displayed on the screen as above, and the spatial light modulator
And one-dimensional light consisting of multiple light control elements
A modulator is placed and the one-dimensional optical modulator
By deflecting the one-dimensional modulated light, the above-mentioned screen
Scan in the direction perpendicular to the length of the one-dimensional optical modulator
Display system with an optical scanning device
In the control method, the scanning speed of the optical scanning device is changed.
Display system control method . 3. The light from a light source is modulated by a light control element.
Based on the spatial light modulator and the video signal from the signal source.
Electronic control device for controlling the light control element of the spatial light modulator
And the modulated light from the spatial light modulator on the screen.
And a projection lens for projecting the image signal into a visible image.
Displayed on the screen as above, and the spatial light modulator
And one-dimensional light consisting of multiple light control elements
A modulator is placed and the one-dimensional optical modulator
By deflecting the one-dimensional modulated light, the above-mentioned screen
Scan in the direction perpendicular to the length of the one-dimensional optical modulator
Control of the display system and the optical scanning device is provided that causes
In the control method, within one line presentation period, one or
Controlling the plurality of light control elements a plurality of times.
Display system control method . 4. The method according to claim 1, wherein
A method for controlling a display system according to claim 1, wherein
The target display system is selective to the wavelength of light
Sequentially transmitted from one or more wavelength selecting means having
Or, a display system that reflects light,
Control method of play system . 5. The method of claim 1, 2 or 3,
A method for controlling a display system according to claim 1, wherein
In the target display system, the light source emits red light.
A red light source that generates, a green light source that generates green light, and blue
Display system consisting of a blue light source that generates colored light
A control method for a display system .