JPH0981079A - Projection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simultaneously input plural picture signals display on one screen by using the picture signals whatever the video systems of the picture signals may differ. SOLUTION: This device is provided with input terminals 11, 12 to which two analog picture signals of different video systems are inputted, A/D conversion circuits 13, 18 making the inputted two picture signals digital signals with samplings synchronized with intrinsic frequencies of respective picture signals, plural memories 15, 19 respectively storing obtained plural digital picture signals, A/D conversion circuits 21, 23 making stored plural signals to analog signals in comformity to one video systems respectively preliminarily set, an analog multiplexer 22 synthesizing obtained plural analog picture signals into one picture signal and a liquid crystal display panel 27 displaying the synthesized picture signal in accordance with drivings of a segment driver 25 and a common driver 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection device, such as a liquid crystal projector, which projects and displays an input image signal on a large screen.

[0002]

2. Description of the Related Art Conventionally, a projection device, such as a liquid crystal projector, which projects and displays an input image signal on a large screen has been widely used. For example, in a liquid crystal projector, an image of a video signal is displayed on a liquid crystal display panel by inputting a video signal from an input signal, and the display image is projected on a large screen by light from a light emitting lamp with high brightness. .

However, in this type of projection device, a video signal such as a composite video signal or an RGB signal is input as an input terminal, and one having one of a plurality of input terminals is used. The image signals input from one input terminal are selectively switched for display.

[0004]

Therefore, when it is desired to simultaneously display two images, for example, an image based on a composite video signal and an image based on an RGB signal in the projection device, the two projection devices are arranged side by side. Image with composite video signal in R
There is no other way but to display the image by the GB signal, or to display the image on the necessary side at that time by switching the input selection with one projection device. It was not possible to display two images at the same time.

Further, particularly in the case of a video signal having a completely different video system such as a composite video signal and an RGB signal for a personal computer, it is difficult to combine these images into a single image signal. Therefore, it becomes more difficult to display two images simultaneously with one projection device.

The present invention has been made in view of the above situation, and an object thereof is to use a plurality of systems of input image signals in one screen even if the video systems are different. An object of the present invention is to provide a projection device which can be simultaneously displayed on.

[0007]

Means for Solving the Problems That is, the present invention is as follows. (1) Input means for inputting a plurality of analog image signals of different video systems, and a plurality of image signals input by the input means Digitizing means for digitizing by sampling in synchronization with the frequency clock, a plurality of image storing means for respectively storing a plurality of digital image signals obtained by the digitizing means, and a plurality of images stored in these image storing means Analogizing means for analogizing each signal in accordance with one preset video system, and synthesizing means for synthesizing a plurality of analog image signals obtained by the analogizing means into one image signal,
Projection display means for projection-displaying the image signal synthesized by the synthesizing means is provided.

As described above, by the hardware configuration, a plurality of input analog image signals having different video systems are once digitized and stored, and then the stored contents are analogized according to one video system, and thereafter, 1
It is designed to be combined with one image signal for projection display, and even if there are multiple systems of image signal inputs of different image systems, there is no limitation to that image system and multiple images are displayed on one screen. Can be displayed at the same time.

(2) In the above item (1), there is further provided a designating means for designating an arrangement state of a plurality of images within one screen, and the synthesizing means corresponds to the designation contents of the designating means. The image signals are combined into one image signal.

With such a structure, the above (1)
In addition to the function of the item, an arbitrary image can be displayed in a state of being arranged at an arbitrary position in one screen. (3) In the above item (2), the designating means selects any one image in the one screen from the first state in which the plurality of images are equally divided and arranged in the one screen. The selected image is switched to the second state in which it is arranged larger than the other images. With such a configuration, in addition to the effect of the above item (2), a desired image can be displayed larger than other images at any time by a simple designation operation.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A first embodiment in which the present invention is applied to a liquid crystal projector will be described below with reference to the drawings.

FIG. 1 shows an example of the circuit configuration.
1 is RGB from a personal computer (not shown)
An RGB input terminal for inputting a signal, and a video input terminal 12 for inputting a composite video signal from the video tape recorder or the like, for example, in the NTSC system.

RGB input from the RGB input terminal 11
The signal is digitized by the A / D conversion circuit 13 by the sampling clock from the controller 14 that matches the horizontal scanning synchronization frequency and the vertical scanning synchronization frequency of the video system corresponding to the specifications of the personal computer, and then the controller 14 is also digitized. It is written in the memory 15 by the write enable signal from.

The composite video signal input from the video input terminal 12 is separated by a Y / C separation circuit 16 into a luminance signal Y and color difference signals Y-R and Y-B, and these are separated. The chroma signal is subjected to chroma processing in the chroma circuit 17 to be converted into an RGB signal.

The RGB signal converted by the chroma circuit 17 is digitized by the A / D conversion circuit 18 by the sampling clock from the controller 14 which matches the horizontal scanning synchronizing frequency and the vertical scanning synchronizing frequency of the NTSC system. After that, it is written in the memory 19 by the write enable signal from the controller 14 as well.

Here, the controller 14 is operated based on a control signal from a microcomputer (shown as "microcomputer" in the figure) 20 which controls the operation of the entire liquid crystal projector by key input from a key input section (not shown). It outputs a timing control signal and sends a read enable signal to the memories 15 and 19 in addition to the write enable signal.

However, the memory 15 is the controller 14
The stored image data is sequentially read according to the read enable signal from and output to the D / A conversion circuit 21. In the D / A conversion circuit 21, the image data is converted into an analog value by a clock that is sent from the controller 14 and matches the horizontal scanning synchronization frequency and the vertical scanning synchronization frequency of the video system corresponding to the preset specifications of the personal computer. Are converted to RGB signals and sent to the analog multiplexer 22.

Similarly, the memory 19 also sequentially reads the stored image data according to the read enable signal from the controller 14 and outputs it to the D / A conversion circuit 23. In the D / A conversion circuit 23, the image data is converted into an analog value by a clock which is sent from the controller 14 and which matches the horizontal scanning synchronizing frequency and the vertical scanning synchronizing frequency of the video system corresponding to the preset personal computer specifications. Are converted to RGB signals and sent to the analog multiplexer 22.

The analog multiplexer 22 is also supplied with a fixed RGB signal of a preset background color, for example, blue, from the background color generator 24. The analog multiplexer 22 is inputted from the controller 14. D is set by each 1-bit switching signal SW1, SW2.
RGB signal from the A / A conversion circuit 21, D / A conversion circuit 2
The RGB signal selected from the RGB signals from No. 3 and the RGB signal from the background color from the background color generation unit 24 is selected.
The signal is sent to the segment driver 25.

The segment driver 25, together with the common driver 26, drives the display of the segment electrodes and the common electrodes of the transmissive liquid crystal display panel 27 to be driven. The drive timing of the segment driver 25 is from the controller 14 described above. The RGB signals from the analog multiplexer 22 are sequentially applied to the segment electrodes in accordance with the timing signal from the display control unit 28 which receives the control signal.

The common driver 26 also sequentially operates and drives the common electrodes of the liquid crystal display panel 27 in accordance with the timing signal from the display controller 28. The display content on the liquid crystal display panel 27 is projected by a high-intensity light source lamp (not shown), and is also projected by a projection lens (not shown) provided at a position facing the light source lamp with the liquid crystal display panel 27 sandwiched therebetween. The image is enlarged and is projected and displayed on a screen or the like.

In the above structure, it is assumed that the RGB signal from the personal computer is input to the RGB input terminal 11 and the composite video signal from the video tape recorder or the like is input to the video input terminal 12. .

When a key input for selecting only an image from a personal computer is made by a key input unit (not shown), the microcomputer 20 receiving the key input sends a control signal to the controller 14.
In the controller 14, the memory 1
5, a read enable signal is sent, a clock for analogization is sent to the D / A conversion circuit 21, and the analog multiplexer 22 is supplied with signals (0, 0) as the switching signals SW1 and SW2, for example.

The analog multiplexer 22 supplies only the RGB signals sent from the D / A conversion circuit 21 to the segment driver 25 as they are according to the contents of the switching signals SW1 and SW2, and the personal computer as shown in FIG. The image I from is displayed on the entire surface of the liquid crystal display panel 27.

Subsequently, when a key input is performed by a key input unit (not shown) to display an image from a personal computer in addition to an image from a video tape recorder in a window at the lower right of the screen, the key input is received. When the microcomputer 20 sends a control signal to the controller 14, the controller 14 sends a read enable signal to the memory 15 on the basis of the control signal.
Clocks for analogization are respectively sent to the A / A conversion circuit 21 in the same manner as described above, and at the same time as the window display timing on the screen, a read enable signal is read out to the memory 19 at a thinning rate that matches the window screen size. Is sent to the D / A conversion circuit 21 for analogization, and the analog multiplexer 22 outputs (0, 1) as the switching signals SW1 and SW2 at the window display timing in one screen, for example. At the timing, a signal that becomes (0, 0) is given as in the above.

The analog multiplexer 22 appropriately selects the D / A conversion circuit 21 according to the contents of the switching signals SW1 and SW2.
2 or the RGB signal from the D / A conversion circuit 23 is selected, the selected RGB signal is supplied to the segment driver 25, and a personal computer as shown in FIG. Image I of the parent screen,
The liquid crystal display panel 27 displays a picture-in-picture screen in which an image II from a video tape recorder or the like is used as a child screen by a window.

Similarly, when a key input for selecting only an image from a video tape recorder or the like is performed, or when a key input for displaying an image from a personal computer in a window in addition to an image from the video tape recorder or the like is performed. Based on this control signal, the controller 14 sends a read enable signal to the memories 15 and 19, a clock for analogization to the D / A conversion circuits 21 and 23, and a switching signal to the analog multiplexer 22 as required. As SW1 and SW2, appropriate signals (0, 1) or (0, 0) at the window display timing are given.

Depending on the contents of the switching signals SW1 and SW2, the analog multiplexer 22 outputs the RGB signal sent from the D / A conversion circuit 23 as it is, or the D / A conversion circuit is temporarily displayed at the window display timing. The segment driver 2 performs the selection process of selecting the RGB signal from the reference numeral 21 and outputs the selected RGB signal.
5, the picture-in-picture screen is displayed on the entire screen with only the image from the videotape recorder or the picture-in-picture screen with the image from the videotape recorder as the parent screen and the image from the personal computer as the child screen by the window. It is displayed on the panel 27 and projected.

When an image is not input to the RGB input terminal 11 or the video input terminal 12 and a key input for designating an image that has not been input as a parent screen or a child screen is performed, the image is replaced with that image. Background color generator 2
The background color image using the RGB signals from No. 4 is displayed to inform the user that the image has not been input.

(Second Embodiment) A second embodiment in which the present invention is applied to a liquid crystal projector will be described below with reference to the drawings.

In this case, the circuit configuration is the same as that shown in FIG. 1, and the same parts are designated by the same reference numerals and the description thereof will be omitted. Hereinafter, the operation will be described.

It is assumed that the RGB signal from the personal computer is input to the RGB input terminal 11 and the composite video signal from the video tape recorder or the like is input to the video input terminal 12, respectively.

When a key input for selecting both an image from a personal computer and an image from a video tape recorder or the like is made by a key input unit (not shown), the microcomputer 20 receiving the key input sends a control signal to the controller 14. Is sent, the controller 14
Then, based on this control signal, the memory 1 is adjusted at a thinning rate that matches the size of the screen at an appropriately different timing in one screen.
Read enable signal to either 5 or 19
A clock for analogization matching the display timing of each image on the screen is sent to the A / A conversion circuits 21 and 23, and the analog multiplexer 22 is appropriately switched as switching signals SW1 and SW2 (0, 0) ( 1,0)
A signal in which any one of (0, 1) is switched and selected is given.

That is, according to the contents of the switching signals SW1 and SW2, the analog multiplexer 22 sends the RGB signal sent from the D / A conversion circuit 21 at the scan timing corresponding to the upper left of the screen and the RGB signal sent at the scan timing corresponding to the upper right of the screen. The background color RGB signal from the background color generator 24 is the same as the background color RGB signal from the background color generator 24 at the scan timing corresponding to the lower left of the screen, and the D / D signal at the scan timing corresponding to the lower right of the screen. A conversion circuit 2
By selectively using the RGB signals from 3, the screen is equally divided into four, and the RGB from the D / A conversion circuit 21 is displayed on the upper left.
Signals, an RGB signal of one background color from the background color generator 24 is arranged in the upper right and lower left, and an RGB signal from the D / A conversion circuit 23 is arranged in the lower right, and a selection process is performed.
The B signal is supplied to the segment driver 25, and a liquid crystal display panel 27 displays a four-divided screen by the image III from the personal computer, the background color images IV and V, and the image VI from the video tape recorder as shown in FIG. The projection display is performed.

From such a display state, for example, by performing a key input such as enlarging the image III from the personal computer in the key input section, the microcomputer 20 receiving the key input sends a control signal to the controller 14. Then, based on this control signal, the controller 14 sends the read enable signal with a further reduced thinning rate to the memory 15 and the read enable signal with a further reduced thinning rate to the memory 19 in the D / A conversion circuit. Clocks for analogization that match the display timing of each image on the screen are sent to 21 and 23, and the analog multiplexer 22 receives, for example, a switching signal SW.
1, SW2 as appropriate (0,0) (1,0) (0,1)
One of the above is selected and given.

The analog multiplexer 22 is responsive to the contents of the switching signals SW1 and SW2, the RGB signal sent from the D / A conversion circuit 21, the RGB signal of the background color from the background color generator 24, and the D / A conversion circuit 23. Using the RGB signals from, the screen is unevenly divided into four, and the D / A conversion circuit 2 is provided at the scanning display timing in the range from the upper left to the center.
The RGB signal from No. 1 is D / A converted at the scanning display timing in the upper right and lower left corners, and the RGB signal of one background color from the background color generator 24 is scanned and displayed in the lower right range. A selection process for selecting an RGB signal from the circuit 23 is performed, the selected RGB signal is supplied to the segment driver 25, and the image III from the personal computer as shown in FIG. 4 is enlarged with the end point P1 at the upper left of the screen as a reference. Then, in accordance with this, the image VI from the video tape recorder or the like is reduced with the end point P2 at the lower right of the screen as a reference 4
The split screen is displayed on the liquid crystal display panel 27 and projected.

Contrary to the above, the image VI from the video tape recorder or the like is enlarged with the end point P2 at the lower right of the screen as a reference, and in accordance with this, the image III from the personal computer is referenced at the end point P1 at the upper left of the screen. It is also possible to reduce it.

By performing such display switching, the image III from the personal computer and the image VI from the video tape recorder or the like are both enlarged and displayed at the same time without changing their aspect ratios. be able to.

In the above operation, the shift from the uniform split screen to the uneven split screen in which one is enlarged and the other is reduced is performed by one key input.
The display size of each image may be freely changed by sequentially controlling the number from 4 to the analog multiplexer 22.

In the first and second embodiments, the image actually displayed is input from the RGB input terminal 11 by the personal computer and the video input terminal 12. Although the case of only two images with a video tape recorder or the like is shown, the present invention is not limited to this, and three or more, for example, four input terminals may be provided to display four images at the same time.

In this case, for example, by selecting and designating one (for example, image VII) from the screen in which four images VII to X are equally divided and displayed as shown in FIG. As shown in (B), only the selected and designated image can be displayed in a larger size than the other images.

Further, as shown in FIG. 5B, the image areas XI and XII of the background color are provided in the screen and are displayed at the same time, so that the reduced images VIII to X also lose their original aspect ratios. Can be displayed without

Even in the case shown in FIG. 5, as in the case of FIGS. 3 and 4, one image is enlarged and another image is reduced to an uneven divided screen. Transition 1
The display size of each image may be freely changed by sequentially performing the input in multiple steps. As described above, the present invention is not limited to the embodiments, and various modifications can be made without departing from the scope of the invention.

[0044]

As described above in detail, according to the present invention, even if the video systems are different, it is possible to simultaneously display on one screen using input image signals of a plurality of systems. Can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration according to a first embodiment of the present invention.

FIG. 2 is a diagram exemplifying a change of a display screen according to the same embodiment.

FIG. 3 is a diagram illustrating a display screen according to a second embodiment of the present invention.

FIG. 4 is an exemplary view showing a display screen according to the embodiment.

FIG. 5 is a diagram illustrating another display screen according to the same embodiment.

[Explanation of symbols]

 11 ... RGB input terminal 12 ... Video input terminal 13, 18 ... A / D conversion circuit 14 ... Controller 15, 19 ... Memory 16 ... Y / C separation circuit 17 ... Chroma circuit 20 ... Microcomputer 21, 23 ... D / A conversion circuit 22 ... Analog multiplexer 24 ... Background color generation unit 25 ... Segment driver 26 ... Common driver 27 ... Liquid crystal display panel 28 ... Display control unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H04N 5/265 H04N 5/45 5/45 G06F 15/66 450

Claims (3)

[Claims] 1. An input unit for inputting a plurality of analog image signals of different video systems, and a digital unit for digitizing the plurality of image signals input by the input unit by sampling synchronized with a frequency clock specific to the image signal. Converting means, a plurality of image storing means for storing a plurality of digital image signals obtained by the digitizing means, and a plurality of image signals stored in these image storing means into one preset video system. Analogizing means for analogizing in accordance with the above, and a plurality of analog image signals obtained by this analogizing means
A projection device comprising: a synthesizing unit for synthesizing one image signal and a projection display unit for projection-displaying the image signal synthesized by the synthesizing unit. 2. A designation means for designating an arrangement state of a plurality of images within one screen, wherein the synthesizing means corresponds to the designation contents of the designation means and outputs a plurality of analog image signals as one image signal. The projection device according to claim 1, wherein the projection device is synthesized as follows. 3. The designating means selects the image selected by selecting any one image in the one screen from the first state in which the plurality of images are equally divided and arranged in the one screen. The projection apparatus according to claim 2, wherein the projection is switched to a second state in which the image is arranged larger than other images.