JPH06217240A - Multi-projector device - Google Patents

Abstract

PURPOSE:To obtain the multi-projector device which nearly equalizes the luminance of overlap parts of divided images from respective projectors to the luminance of non-overlap parts. CONSTITUTION:This device is equipped with a horizontal and vertical signal generating means VP which generates an overlap signal corresponding to the extent of horizontal overlapping between the projection images from the projectors and a total luminance control signal generating means which generates a luminance timing signal corresponding to the periods of horizontal and vertical overlapping between the images according to respective overlap signals from the means VP and a horizontal and a vertical synchronizing signal for placing the projections in operation; and the total luminance control signal generating means generates a luminance timing signal for lowering the luminance to 1/2 when an overlap signal is supplied from the horizontal or vertical signal generating means or to 1/4 when overlap signals are supplied from the both, thereby projecting the images while imposing luminance modulation according to the luminance timing signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-projector apparatus which projects a continuous image by using a plurality of synchronous scanning type projectors, and more particularly, a multi-projector apparatus which adjusts the brightness in the overlapping portion of the images by the respective projectors. -Regarding the projector device.

[0002]

2. Description of the Related Art As shown in FIG. 16, for example, a plurality of synchronous scanning type projectors 90 are used to combine images taken by a plurality of image capturing devices and project them on a huge screen.
The divided images are projected on the large screen 91 by a, 90b, and 90c to form one combined image.

In this case, the projectors 90a, 90
Since the light from the plurality of projectors 90a, 90b, 90c is projected, the overlapping portion of the images by b and 90c has a brightness according to the number of overlapping projectors, as shown in FIG. That is, each side A of each divided image in the horizontal direction has twice the luminance because the projected images from the two projectors overlap each other, and each side B of each divided image in the vertical direction also has twice the luminance. The brightness is 4 at the four corners C where both horizontal and vertical directions overlap.
Since the images on the stand overlap, the brightness becomes four times higher.

[0004]

Therefore, the brightness is greatly different between the non-overlapping portion and the overlapping portion of the images, and an image divided into divided images is seen as the whole image, which is very annoying. . For this reason, there is a screen in which the border portion is made black to make the image in that portion invisible.

The present invention has been made in consideration of the above points, and provides a multi-projector device which can make the brightness of the overlapping part of the divided images by each projector similar to the brightness of the non-overlapping part. The purpose is to

[0006]

In order to achieve the above object, in the present invention, a video signal from a plurality of video sources is given to each of a plurality of synchronous scanning type projectors and projected as a composite video of the images projected by the respective projectors. In the projector device, the horizontal signal forming means for forming an overlapping signal according to the degree of horizontal overlapping of the projected images by each of the projectors, and the degree of vertical overlapping of the projected images by each of the projectors. Vertical signal forming means for forming a corresponding overlapping signal, the respective overlapping signals from the horizontal signal forming means and the vertical signal forming means, and the images based on the horizontal synchronizing signal and the vertical synchronizing signal for operating the projector. Luminance forming a luminance timing signal corresponding to the horizontal and vertical overlapping times And a luminance timing signal forming means for halving the luminance when an overlapping signal is given from one of the horizontal signal forming means and the vertical signal forming means, and for overlapping from both. It is characterized in that when a signal is given, a luminance timing signal that makes the luminance 1/4 is formed, and the image is projected while luminance-modulating the image according to the luminance timing signal.

[0007]

[Operation] Therefore, the plurality of synchronous scanning type projectors sequentially project the images photographed in a divided manner on a predetermined screen of a huge screen by scanning. The divided images have portions that overlap each other and are projected without breaks.

A plurality of projectors project the same portion on the screen in an overlapping manner in accordance with the degree of overlap between the images of the projectors. The horizontal signal forming means and the vertical signal forming means form respective overlapping signals in accordance with the scanning time of this overlapping projection.

These overlapping signals are supplied to the luminance timing signal forming means. The brightness timing signal forming means is provided from either the horizontal signal forming means or the vertical signal forming means in accordance with the horizontal synchronizing signal and the frame signal from the video source and the overlapping signal from the horizontal signal forming means and the vertical signal forming means. A luminance timing signal that halves the luminance when the overlapping signal is given and ¼ when the overlapping signal is given from both sides, and the luminance modulation of the image is performed according to the luminance timing signal. Project while doing.

As a result, the brightness of the overlapping portions of the images from the respective projectors is reduced according to the number of projectors in which the overlapping has occurred, and the entire screen has a uniform luminance.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a video signal processing circuit VP having a brightness control function used in a multi-projector apparatus of the present invention. This circuit receives a video signal including horizontal and vertical sync signals and a frame signal from a video source, and controls the level of the video signal by a control signal formed with the sync signal as a reference to perform a brightness modulation video signal. Is converted into and given to the projector.

That is, the video signal supplied from the input terminal IN is amplified by the input amplifier 1, the pedestal level is fixed by the DC clamp circuit 2 and output to the voltage control gain amplifier 3, and the horizontal separation is performed by the sync separation circuit 4. The signal and the vertical synchronizing signal are taken out, both the synchronizing signals are given to the voltage control gain amplifier control signal generator 5, and the horizontal control signal and the vertical control signal for brightness control are generated based on the timing of these both synchronizing signals. Then, the voltage control gain amplifier 3 is supplied. The voltage control gain amplifier 3 amplifies the video signal from the DC clamp circuit 2 whose pedestal level is fixed according to the horizontal control signal and the vertical control signal from the voltage control gain amplifier control signal generator 5, and It outputs to the output terminal OUT via the output amplifier 6.

FIG. 2 shows the DC clamp circuit 2 shown in FIG.
FIG. 6 is a diagram for explaining a DC clamp operation by the method.

Input amplifier 1 supplied from input terminal IN
The pedestal level of the video signal amplified by is fixed at DC0V by the DC clamp circuit 2. The luminance level of an NTSC television video signal is determined by the potential difference from the pedestal level, so the pedestal level must be fixed.

Then, the pedestal level is set to DC0V, and the value of the horizontal synchronizing signal is -0.285V, 100, for example.
Set the% white level to 0.715V.

The video signal whose pedestal level is fixed by the DC clamp circuit 2 is applied to the voltage control gain amplifier 3. The voltage control gain amplifier 3 controls the level of the video signal by being supplied with horizontal and vertical control signals. If the horizontal and vertical control signals are 1, the voltage is at the same level as the input, and if it is 1/2, it is 1 / 2 times the level, 1/4
In that case, the brightness of the video signal is controlled to a level of 1/4.

The sync separation circuit 4 takes out the horizontal sync signal, the vertical sync signal and the frame signal superimposed on the video signal and supplies them to the voltage control gain amplifier control signal generator 5.

FIG. 3 shows how the horizontal control signal is formed based on the horizontal sync signal from the sync separation circuit 4 (because the vertical control signal is greatly different in scale from the horizontal sync signal). Not shown.).

As shown in FIG. 3A, the horizontal synchronizing signal is separated from the video signal having the horizontal blanking period and the image display period. FIG. 6B shows the separated horizontal synchronizing signal.

With reference to this horizontal synchronization signal, as shown in (c) of the figure, it rises at the rising timing of the horizontal synchronization signal until the end of the blanking period.
A signal is formed which lasts for a time T1 corresponding to 5 μS.

The time t corresponding to the overlapping width on the left side of the screen falls when the signal shown in FIG.
The pulse shown in (d) of FIG. This is a part of the horizontal control signal.

At the same time, as shown in FIG.
A signal is formed which rises at the beginning of the image display period and lasts for the time T2 corresponding to the period until reaching the overlapping portion on the right side of the screen.

The time t corresponding to the overlapping width on the right side of the screen rises when the signal shown in FIG.
A signal lasting only 2 is shown in (f) of the figure.
This is a signal that forms a horizontal control signal together with the signal shown in FIG.

(G) of the figure is (d) and (f) of the figure.
2 shows a horizontal control signal based on the signal of FIG. With this horizontal control signal, the voltage control gain amplifier 3 reduces the level of the video signal by half.

FIG. 4 shows an example of a circuit configuration for forming the horizontal control signal shown in FIG. When the horizontal sync signal is given from the sync separation circuit 4, the one-shot multi-vibrator 41 forms a signal (shown in (c) of FIG. 3) that lasts for T1 = 10.5 μS to form two one-shot multi-vibrators 42, 43. Give to.

The one-shot multivibrator 42 is
A signal that lasts for a time t1 corresponding to the overlapping width on the left side of the screen shown in FIG. 3D is formed and given to the combining circuit 45. Further, the one-shot multivibrator 43 forms a signal that lasts for a time T2 corresponding to the image display period shown in (e) of FIG.

The one-shot multivibrator 44 is
A signal that lasts for a time t2 corresponding to the overlapping width on the right side of the screen shown in FIG. The synthesizing circuit 45 synthesizes signals corresponding to the overlapping widths on the left and right sides of the screen to form a horizontal control signal.

FIG. 5 illustrates the vertical control signal.
The first field F that constitutes one screen, that is, one frame
It shows the overlapping width of the first and second fields F2. That is, 262.5 forming the first field F1
Among the scanning lines, a predetermined number of upper lines shown as the first block f11 and a predetermined number of lower lines shown as the second block f12 are within the overlapping width. Of the 262.5 scanning lines forming the second field F2, the third block f
A predetermined number of upper parts shown as 21 and the fourth block f2
A predetermined number of lower parts shown as 2 are within the overlapping width.

FIG. 6 shows the first to fourth blocks f1.
1 shows a composite signal, a horizontal synchronizing signal, a frame signal and a vertical control signal including a portion of the vertical overlapping width of 1, f12, f21 and f22. It is a representation.

The first field F1 includes 0H to 262.
Including the horizontal scanning period up to 5H, 0H to 21H is a vertical blanking period, and the first block f11 portion by a predetermined number of horizontal scanning lines from 21H is an overlapping portion on the upper part of the screen, which is before 262.5H. The second block f12 formed by a predetermined number of horizontal scanning lines is the overlapping portion at the bottom of the screen.

Similarly, the second field F2 is 262.5.
The horizontal scanning period from H to 525H is 262.5.
H to 283.5H is a vertical blanking period, and 283.
Third block f21 from 5H by a predetermined number of horizontal scanning lines
Is an overlapping part on the upper part of the screen, and the fourth block f22 formed by a predetermined number of horizontal scanning lines before 0H is an overlapping part on the lower part of the screen.

Further, (a) of the figure is a composite signal, (b) of the figure is a horizontal synchronizing signal separated from the composite signal, (c) of the figure is a frame signal separated from the composite signal, (D) is a vertical control signal for adjusting the brightness at the overlapping portion in each of the first and second fields F1 and F2.

FIG. 7 shows a first example of the overlapping portion shown in FIG.
The horizontal scanning lines of the field F1 and the second field F2 are shown, and the blanking period is ignored here. That is, the first field F1 is composed of the horizontal scanning lines from the first half to the first half of the 263rd, and the second field F2 is composed of the horizontal scanning lines from the second half of the 263rd to the 525th.

FIG. 8 shows a part of the internal configuration of the voltage control gain amplifier control signal generator 5 shown in FIG. 1. The horizontal synchronizing signal and the frame signal shown in FIGS. 6 (b) and 6 (c). The circuit for forming the vertical control signal shown in FIG.

The operation of this circuit is as follows. That is,
The 10-bit binary counter 51 counts with the horizontal synchronizing signal as a clock signal while being cleared by the frame signal. The count output is given to the position detection decoder 52, and the first to fourth blocks f11 and f1 in FIG.
The data at positions corresponding to 2, f21 and f22 are distributed to the overlapping width setting circuits 53a, 53b, 53c and 53d.

For the first field F1, the first field upper overlap width setting circuit 53a outputs a set value of the width obtained by adding the overlap width of the first block f11 to the blanking period 0H to 21H to the combining circuit 54. To do. The first field lower overlap width setting circuit 53b causes the combination circuit 54 to set a width value obtained by subtracting the overlap width of the second block f12, which is the last horizontal scanning line of the first field F1 from the second block f12. Output.

Also, regarding the second field F2, the second
The field upper overlap width setting circuit 53c combines the set value of the width obtained by adding the overlap width of the third block f21 to the blanking period of 262.5H to 283.5H and the synthesizing circuit 5
Output to 4. Second field lower overlap width setting circuit 5
3d outputs the set value of the width obtained by subtracting the overlapping width of the fourth block f22, which is the last horizontal scanning line of the first field F1 from the 525th horizontal scanning line, to the synthesizing circuit 54.

As a result, the synthesizing circuit 54 outputs the vertical control signal of the overlapping portion corresponding to the first to fourth blocks in FIG. This vertical control signal is given to the voltage control gain amplifier 3 in FIG. 1 together with the horizontal control signal from the circuit in FIG. 4, and the brightness control of the projector is performed based on this.

FIG. 9 shows the total luminance control signal forming means 31 included in the voltage control gain amplifier 3 of FIG. 1, and the composite signal included in the video signal from the DC clamp circuit 2 of FIG. The total brightness control signal is formed based on the horizontal control signal by the horizontal control signal forming circuit and the vertical control signal by the vertical control signal forming circuit of FIG.
The total brightness control signal forming means 31 is provided with a composite signal including a signal indicating a blanking period and the horizontal control signal and the vertical control signal from the horizontal and vertical control signal forming circuits to form the total brightness control signal. .

FIG. 10 shows the total brightness control signal from the circuit of FIG. 9 as the projector 90a, 90b, 90 of FIG.
One split video screen 9 on the large screen 91 by c
It is a figure for corresponding and explaining with 1a. It is necessary to adjust the brightness only on the screen side A, which is the four sides of the screen in FIG.
And B are the screen corners C which are the four corners, and these parts are controlled as shown in Table 1 below. The central portion D of the screen and the blanking portion E do not require brightness adjustment.

[0041]

[Table 1]

As described above, the luminance is halved on the four sides A and B of one divided video screen 91a, and the luminance is 1 on the four corners C.
When it is multiplied by / 4, the entire screen has uniform brightness.

Further, if the brightness of the blanking period is multiplied by 1, the brightness adjustment as shown in Table 2 below is performed. This is the standard value of the amplitude of the video sync signal, -0.2.
This is a necessary treatment to maintain the voltage at 85V.

[0044]

[Table 2]

FIG. 11 is a timing chart showing the brightness control signals described in Tables 1 and 2 above. In this figure, only the first field F1 is shown. (A) of the figure shows a composite signal, and various signals as shown in (b) to (e) of the figure are formed in the vertical overlapping portion. A signal for fixing the luminance is formed in the vertical blanking portion.

With respect to the vertical overlapping portion, the horizontal control signal for brightness reduction shown in (b) of the figure occurs at both ends of the area sandwiched by the horizontal synchronizing signals in the composite signal shown in (a) of the figure. Further, the blanking period occurs in the period including the vertical synchronizing signal, as shown in (c) of FIG. The vertical control signal is generated so as to coincide with the vertical overlap period, as shown in (d) of FIG.

When the horizontal control signal shown in (b) of the same figure and the vertical control signal shown in (d) of the same figure are combined, an overall brightness control signal as shown in (e) of the figure is obtained. To be
That is, as shown in FIG. 12, which is an enlarged view of the vertically overlapping portion of FIG. 8E, the gain is 1/2 at position B on the screen, 1/4 at position C, and 1 at position E.

FIG. 13 shows an example in which the video signal processing circuit VP having the brightness control function of FIG. 1 is incorporated in a video projector. In this example, when projection is performed by a plurality of projectors 90a, 90b, 90c by a plurality of laser disc players 60a, 60b, 60c, each laser disc player 60a, 60b, 60c.
Between the projector and each of the projectors 90a, 90b and 90c.
Signal processing circuits VP1 and VP having the brightness control function of
2 and VP3 are incorporated to make the brightness of the screen uniform. In this case, the laser disc players 60a, 60b, 60c
They are synchronized with each other.

In the example of FIG. 14, the video signal processing circuits VP1, VP2 and VP3 having the brightness control function of FIG. 1 are not incorporated as in FIG. 13, but laser disk players 60a, 60b and 60c and a projector 90a are provided. , 9
0b and 90c are used independently.

FIG. 15 shows the processing by the video signal processing circuit VP so that an image in which the brightness of the entire screen is made uniform can be projected without using the video signal processing circuit VP having the brightness control function of FIG. It shows a configuration for recording the applied video signal. That is, the video signal processing circuit VP is inserted between the video tape recorder 70 and the laser disk maker 80 to perform signal processing, and the brightness of the screen of the multi-projector device is made uniform.

[0051]

As described above, according to the present invention, when video signals from a plurality of video sources are respectively applied to a plurality of synchronous scanning type projectors and projected as a composite video of the projection video by each projector, the projection video by each projector Since the luminance of the overlapping portion between the two is reduced according to the degree of the overlapping, the entire screen has uniform luminance and the image can be easily viewed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a video signal processing circuit having a brightness control function used in a projection apparatus of the present invention.

FIG. 2 is a diagram for explaining a DC clamp operation by a DC clamp circuit in FIG.

FIG. 3 is a diagram showing how a horizontal control signal is formed based on a horizontal sync signal HD from a sync separation circuit.

FIG. 4 is a diagram showing an example of a circuit configuration for forming a horizontal control signal shown in (g) of FIG.

FIG. 5 is a diagram showing an overlapping width of a first field and a second field forming one screen, that is, one frame, for explaining a vertical control signal.

FIG. 6 is a diagram showing a composite signal, a horizontal synchronizing signal, a frame signal, and a vertical control signal, including a vertical overlapping width portion of the first to fourth blocks of the first field and the second field.

FIG. 7 is a diagram showing horizontal scanning lines of a first field and a second field.

8 is a diagram showing a part of the internal configuration of the voltage controlled gain amplifier control signal generator shown in FIG.

9 is a diagram showing a total brightness control signal forming means included in the voltage control gain amplifier of FIG.

FIG. 10 shows a total brightness control signal by the circuit of FIG.
6 is a diagram for explaining in association with one divided video screen on a large screen by each projector of FIG.

FIG. 11 is a timing chart showing the brightness control signals described in Table 1 and Table 2.

FIG. 12 is an enlarged view of the vertical overlapping part of FIG. 11 (e).

13 is a diagram showing an example in which the video signal processing circuit having the brightness control function of FIG. 1 is incorporated in a video projector.

FIG. 14 is a diagram showing an example in which the video signal processing circuit having the brightness control function of FIG. 1 is used independently of a player and a projector.

15 is a diagram showing a configuration in which a video signal processed by a video signal processing circuit having a brightness control function of FIG. 1 is recorded.

FIG. 16 is a diagram of a conventional example in which divided images are projected on a screen by a plurality of synchronous scanning projectors to form a composite image.

FIG. 17 is an explanatory diagram showing a conventional screen having brightness according to the number of overlapping projectors.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Input amplifier 2 ... DC clamp circuit 3 ... Voltage control gain amplifier 4 ... Synchronous separation circuit 5 ... Voltage control gain amplifier control signal generator 6 ... Video signal output amplifier 31 ... Total brightness control signal forming means 41, 42, 43, 44 ... One-shot multivibrator 45 ... Compositing circuit 51 ... 10-bit binary counter 52 ... Position detection decoder 53a, 53b, 53c, 53d ... Overlap width setting circuit 54 ... Combining circuits 90a, 90b, 90c ... Synchronous scanning projector 91 ... Large screen 91a ... Split video screen A, B ... Screen side C ... Screen corner D ... Screen center E ... Blanking part

Claims (1)

[Claims] 1. A multi-projector device for applying video signals from a plurality of video sources to a plurality of synchronous scanning projectors respectively and projecting the video signals as a composite video of the video images projected by the respective projectors. Horizontal signal forming means for forming an overlap signal according to the degree of horizontal overlap, vertical signal forming means for forming an overlap signal according to the degree of vertical overlap between the projection images from each of the projectors, Luminance timing corresponding to the horizontal and vertical overlapping timings of the images based on the overlapping signals from the horizontal signal forming means and the vertical signal forming means, and the horizontal synchronizing signal and the vertical synchronizing signal for operating the projector. And a brightness timing signal forming means for forming a signal. The video signal forming means halves the brightness when an overlapping signal from one of the horizontal signal forming means and the vertical signal forming means is applied, and sets the brightness to 1 when an overlapping signal from both is applied. A multi-projector device characterized in that a luminance timing signal for making / 4 is formed, and an image is projected while being subjected to luminance modulation according to the luminance timing signal.