JPH04196696A - Line of sight coincident communication system for animation window - Google Patents

Abstract

PURPOSE:To reduce the line of sight deviation by placing a time intermittent type light transmission control screen between an image pickup device and the eye ball position of the communicator as a display device. CONSTITUTION:One or plural number of cameras 2A are placed in front of the observer 3A and the light transmission control screen 4A, for an example a liquid crystal dimmer glass, is placed in front of the camera. This time intermittent light transmission screen is simultaneously used as a display and one or plural number of communication called parties 3B's images are displayed as windows in one or plural number of small areas. Thus, no physical and optical connecting system is required between the observers of the display surfaces and the operability near the front of the display, such as a keyboard, is not impaired. Furthermore, when plural communication called parties are displayed in the moving picture windows, a more natural line of sight coincidence than a half mirror system is realized.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a line-of-sight matching video window communication system, in particular, in which the space in front of the image display surface is unrestricted for displaying images of multiple communication partners. It is something.

(Prior Art) Conventionally, in face-to-face communication, in which an image of the communication partner (observer) is simultaneously captured and transmitted to the communication partner while looking at the face image of the communication partner, line of sight alignment with the communication partner has been optically realized. The following methods have been proposed.

For example, in order to achieve good line-of-sight alignment when communicating directly with a communication partner that is displayed as a moving image, the optical axes of the imaging system (camera) and display system (display device) may be half mirrored.
A method of coupling is known, and this was announced in the 1986 IEICE Autumn National Conference Lecture D-38r "Development of Line-of-Sight Video Telephone Device".

Another example is a method in which a camera is placed close to the display device, as shown in FIG. In the figure, (1) shows a front view, and (2) shows a side view. A camera 2 is placed above a display device (display) l, and an angle θ (camera 2 and display Eyes E of person 3 gazing at point T at the center of the video window on page 1
(the angle it makes with the line connecting them).

This is an equipment arrangement that does not create a sense of line-of-sight mismatch when the distance between the display surface and the person to be photographed is large.

(Problem to be Solved by the Invention) By the way, in the former prior art described above, it is necessary to place a half mirror at an angle between the imaging system (camera) and the display system (display device), and the half mirror is placed in front of the display surface. There are disadvantages in that it requires a relatively large space and that the viewer cannot get close to the display surface of the display device.

In addition, in the latter conventional technology, the face image of the communication partner is displayed in a video window 1a, which is a small area on the first screen of the display.
In the case of displaying images as , the distance between the display screen and the camera becomes relatively large, which has the disadvantage that the line of sight becomes more misaligned.

Regarding the line of sight misalignment caused by the mismatch between the video display and the position of the imaging device in face-to-face video communication, there is a lecture entitled ``Study on the position of the image pickup tube in video telephony'' held at the 1968 Joint Conference of the Four Electrical Engineers of Japan. It is easy to accept the case where the punch is located relatively upward, and an angle of 12 degrees from the center is known as the punch capacity limit.

The permissible line-of-sight deviation limit specified in this report would be greatly exceeded in the case of window-shaped video display. The arrangement of the video window and camera that satisfies the requirements for an average workstation display is as shown in Figure 5, where the subject 3 is placed in front of him and 1.5 points from his eye (E).
8 (H is the height of the display 1, approximately 45 am for a 19-inch display), and the user is looking at the center point T of the video window 1a on the display surface, and its state is monitored by the camera 2 on the outer edge of the display. Being photographed.

The line of sight deviation in this state is shown in FIG.

That is, FIG. 6 shows the line-of-sight deviation between the window and the camera position when the camera 2 is placed at various positions within the plane including the display surface of the display, and in the figure, L is the center point T of the video window. θ indicates the distance (cm) from the camera 2, and θ indicates the angular difference (degrees) between the center point T of the straight window connecting the camera 2 and the eye E of the person to be photographed and the straight line connecting the eye E of the person to be photographed. .

As can be seen from this figure, the area where the face image of the person to be photographed 3 is captured and displayed in the video window 1a on the first screen is:
Since it is an extremely small area, the position of the camera whose line of sight coincides is limited to the distance and angle difference θ from the center point T of the video window to the range shown by the detection limit M and the tolerance limit N, and the shaded area is the image. This is the part that is not properly captured and displayed.

In other words, in the arrangement of cameras shown in FIG. 5, when the distance between the display surface and the person to be photographed becomes small, line-of-sight mismatch occurs, and a certain distance space is required.

(Objective of the Invention) The present invention solves the above-mentioned drawbacks of the prior art and realizes a line-of-sight video window communication system that does not have space restrictions on the side of the observer who is located in front of the display device and the communicator who is also the subject. The purpose is to provide an imaging and display system that

(Means for Solving the Problems) In order to solve the above problems and achieve the objectives, the present invention provides a face-to-face video communication system in which reproduced images of communication partners are displayed as a window, which is a partial area of the display surface of a display device. And,
The present invention is characterized in that a time-intermittent light transmission control screen is disposed as a display device between the imaging device for obtaining the transmitted image and the eyeball position of the communicator who is the subject and the observer of the other party's image.

In addition, the present invention displays a plurality of windows on a time-intermittent light transmission control screen, and installs a plurality of cameras on a line connecting the eyeball position of the person communicating with the plurality of windows, thereby displaying images of the plurality of communication partners. This corresponds to the camera that obtains the transmitted image.

(Function) The present invention disposes a light transmission control screen, for example, a liquid crystal dimming glass, in front of one or more cameras directly facing the viewer, and simultaneously utilizes this time-intermittent transmission screen as a display. An image display of one or more communication partners is displayed as a window in one or more small areas thereof.

Therefore, since there is no need for a physical optical coupling system between the viewer and the display surface, the operability of the keyboard and other areas near the front of the display is less likely to be impaired. Provides more natural line-of-sight alignment than the other method.

(Embodiment) FIG. 1 shows a layout configuration diagram of an embodiment of the present invention, and in the figure,
2A and 2B are photographed subjects (A) and (B) shown as 3A and 3B.
The imaging system cameras are placed on each side, and the display system 4A,
The light transmission control screen (A) shown by 4B, the photographed person 3A through the center points Ta and Tb of the video window of (B),
It is placed on the line (dotted chain line) connecting the eyeball positions Ea and Eb of 3B. 5A and 5B are window display control units that display output images from the other party's camera and video projectors 6A and 6B.
8 force to.

7A and 7B are synchronization signal generators that synchronize the cameras 2A and 2B with the light transmission control screens 4A and 4B, and 8A and 8B are synchronization signal generators that transmit light through the light transmission control screens 4A and 4B using synchronization signals from the 7A and 7B. and a screen drive circuit to make it non-transparent (scattering), 9 is the person to be photographed (A), (
B) Camera 2A between.

This is a communication path connecting 2B.

FIG. 2 also shows the window display control section 5A shown in FIG.
, 5B and its frame memory access control state diagram (2) are shown. In the same figure (1), 51 is a background image generator, 52 is a synchronization extraction and separation unit,
A video synchronization signal is extracted and separated from the background image generator.

53 is a memory access control unit, 54 is a frame memory O
55 is a frame memory l in which images from the other party's camera are respectively stored, and under the control of the memory access control unit 53, access types (O→1→O) shown in FIG. ...) is selected. 56 is a data bus, 57 is a D/A converter, frame memory 0
, 1 are converted into analogs and sent to video projectors 6A and 6B.

Next, the operation of this embodiment will be explained with reference to the impulse response characteristic diagram of the liquid crystal dimming glass plates used as the light transmission control screens 4A and 4B shown in FIG. 3, and the timing chart of the synchronous operation of this embodiment shown in FIG. do.

The image of the other party, for example, the image of the photographed person 3B, is captured by the camera (B
) A camera signal imaged by 2B and sent via a communication path 9 is converted into a signal in a display area window by a window control unit 5A, and is projected onto a light transmission control screen 4A by a video projector 6A. . This light transmission control screen 4A is brought into a transparent state (transmission in d) regularly for a short period of time by a drive pulse (c) from a screen drive circuit 8A synchronized with a signal from a synchronization signal generator 7A (FIG. 4a, the same applies hereinafter). , and returns to the light scattering state (d scattering) at other times. In this transparent state, the camera 2A performs a high-speed shutter operation (opening operation of e) and the light transmission control screen 4A
An image is taken of the observer (person to be photographed 3A) on the opposite side.

In the above operation, a camera signal obtained by capturing an image of the person to be photographed 3A with the camera A (2A) is also sent to the window display control section 5B via the communication path 9 in the same manner as described above, and the same operation is performed.

Since the line of sight can be aligned with that of the communication partner in this way, a neat imaging/display system with no spatial restrictions on equipment arrangement can be obtained in front of the light transmission control screens 4A, 4B, which are displays.

By performing the high-speed shutter operation sufficiently quickly, the camera is visually hidden by an opaque screen, which has the secondary effect of creating a conversation environment in which the user is not conscious of the camera.

For example, as a screen material for controlling light transmission, 100H
z, Parallel light transmittance when applying 100V is 2 to 76.5%
LCD dimming glass plates, etc. can be used. FIG. 3 shows an example of the impulse response of this liquid crystal light control glass plate.

Since the rise time of the light transmission characteristic is approximately 1 ms,
This is sufficiently shorter than the field period (16.7 m5) of an NTSC video signal, and the above-described imaging and display can be achieved by performing a high-speed shutter operation of the camera at about 1 ms during one field period.

A timing chart of synchronized operation for line-of-sight video window communication is shown in FIG. 4, and the screen drive circuit 8A
, 8B drive time Tw = 3ms, and camera 2A, 2B open (shooting) operation time T5 = 2ms.

When operated under the conditions of field period TV = 16.7 ms, the screen operation has a peak transmittance of 70% and a half width of 4 m.
s is obtained and can be used as an intermittent light transmission control screen.

Next, as shown in FIG. 2, the window display of the moving image is performed by the memory access control unit 53 in the frame memory (0) 54 along the scanning line direction of an arbitrary X line on the display surface of the video projectors 6A, 6B. and frame memory (1)
The respective background screen information stored in 55 and the image from the other camera are sequentially selected at the frame memory access control timing shown in FIG. Ru. Then, the signal is converted into analog and output to the video projectors 6A and 6B.

In the present invention, it is possible to increase the number of video windows, and in this case, a plurality of cameras shown in FIG. This makes it possible to display images of multiple communication partners that convey the natural movement of their gaze, and this can be developed into a conference communication service.

(Effects of the Invention) As explained above, the present invention can reduce line-of-sight deviation in video window communication of workstation displays, which generally has a short viewing distance and can be as large as about 12° to about 53° when the display and camera are placed close together. can be significantly reduced.

Furthermore, the method of the present invention, which uses light transmission control of the liquid crystal dimming glass screen and high-speed operation of the video camera, is preferable as a natural video communication interface in that the person being photographed does not become aware of the camera being within the field of view.

Furthermore, by installing a plurality of cameras, it is possible to display images of a plurality of communication partners, and it can be used for conference communication services.

[Brief explanation of the drawing]

Fig. 1 is a layout configuration diagram of one embodiment of the present invention, and Fig. 2 is a diagram of the arrangement of an embodiment of the present invention.
FIG. 2 is a functional block diagram of a window display control unit and a frame memory access control state diagram shown in the figure. Fig. 3 is an impulse response characteristic diagram of the liquid crystal dimming glass plate, Fig. 4 is a diagram showing a timing chart of the synchronized operation of Fig. 1, and Fig. 5 is a diagram showing the timing chart of the synchronous operation of Fig. 1. The layout relationship diagram, FIG. 6, is a diagram showing the line-of-sight deviation between the window and the camera position. 1...Display, 2.2A, 2B...Camera, 3.3A, 3B...Subject, 4A, 4B
...Light transmission control screen, 5A, 5B...
Window display control unit, 6A, 6B... Video projector, 7A, 7B... Synchronization signal generator,
8A. 8B...Screen drive circuit, 9...Communication path,
51...Background screen generation device, 52...Synchronization extraction separation unit, 53...Memory access control unit, 54...Memory frame 0155...Memory frame 1156...
- Data bus, 57...D/A converter. 7W Input N Exit O

Claims (2)

[Claims] (1) A face-to-face video communication system in which a reproduced image of the other party is displayed as a window, which is a partial area of the display surface of a display device, and the image pickup device for obtaining the transmitted image and the image of the other party as the subject. A line-of-sight video window communication system characterized by disposing a time-intermittent light transmission control screen as a display device between the eyeball position of a communicator who is an observer. (2) Multiple windows are displayed on a time-intermittent light transmission control screen, and multiple cameras are installed on a line connecting the communication person's eyeball position and the multiple windows to display and transmit images of multiple communication partners. 2. The line-of-sight video window communication system according to claim 1, characterized in that the communication system corresponds to a camera that obtains images.