JPH10213776A - Display image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an excellent and inexpensive display image pickup device with simple constitution by providing a hologram arranged on a transparent substrate and diffracting light toward an observer in a picture plane. SOLUTION: The hologram 2, a camera 4 and a projector 3 are provided in a case 5. The projector 3 is held in the case 5 so that a picture may be displayed on the surface of the hologram 2, the camera 4 is housed inside the case 5 and set and held on an opposite side to the observing position by the observer 1 with respect to the hologram 2 so as to be aligned with the line of sight. A power source and a signal line are connected to the camera 4 and the projector 3. By setting the hologram 2 enveloped in laminated glass and the projector 3 to positions where a specified incident angle is obtained, radiating display light from the projector 2, and forming a display picture on the hologram 2, the observer 1 observes the display picture by the projector 3 at a specified angle from the normal of the hologram 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line-of-sight matching type display / imaging device useful for interactive video communication services, and more particularly to a line-of-sight matching display / image pickup device useful for videophones, video conferences and the like.

[0002]

2. Description of the Related Art In recent years, with the development of communication technology, video communication services including not only audio but also video have become widespread, and it is expected that video communication services with even higher functions and more realism will be provided. . In order to realize this realistic video communication, in addition to high functionality such as large screen and high definition,
The gaze matching function is important as a function for providing an environment close to a real conversation environment.

[0003] The eye-gaze matching function is intended to provide an environment in which interlocutors can talk with each other by matching their eyes, as in the case of a real dialogue. This feature allows both parties to feel as if they are talking on the display surface through a glass window placed between them.

[0004] In addition, the gaze matching function enables gaze matching between interlocutors, and enables accurate recognition of the object ahead of the gaze even when the other party is not looking at his / her own face. As described above, the eye-gaze matching function is indispensable for enhancing the realism of an interactive video communication service such as a videophone or a video conference.

[0005] Also, in the broadcasting field, it is necessary to speak to a camera in order to produce a situation in which an announcer is talking to a viewer. The video that I was talking to was sent without looking at the person, and the effect was not obtained. In this case, it is desirable that the original be displayed on an extension of the line connecting the announcer and the camera.

However, in order to provide the effect of eye-gaze matching, the camera must be arranged at a position corresponding to the position of the eye of the opponent on the extension of the eye-gaze of the person watching the display. However, since this position is usually behind the screen, it is impossible to image from such a position with a normal display.

For this reason, in a conventional videophone or videoconference, the camera is often arranged on the upper part of the display, and when talking while looking at the other party's face, both face down as a result. No concordant effect was obtained. In this way, cameras are installed around the screen in conventional videophones and video conference systems,
Most do not have a line-of-sight matching function.

[0008] As a method of matching the line of sight, a method using a half mirror, a method of switching between a display operation and an imaging operation of a display and a camera in a time sharing manner, and the like have been proposed.

In the method using the half mirror, the positions of the display and the camera are overlapped by using optical components. Since the half mirror is a mirror that partially transmits and partially reflects the incident light, a half mirror that is tilted by about 45 ° is placed in front of the observer, a display is placed behind the half mirror, and the half mirror is positioned at the position where the light is reflected by the half mirror. By placing the camera, the position of the camera and the display can be matched.
Example of configuring a small videophone using a half mirror (for example, Suetake, Yoshikawa: Development of eye-gaze-matching small videophone, IEICE Fall, D-38, 1988), and a device for reading a broadcast manuscript (Prompta) (For example, Kuwata: LCD Prompter, Asahi Glass Research Report, 33, N
o. 2, pp 351-361, 1988).

This method has an advantage that the line of sight can be easily matched by using only one half mirror. However, since the half mirror larger than the display surface is installed obliquely, the half mirror is tilted as a whole device. This has the disadvantage that the volume is increased by that much and the size is increased, and the display angle is narrowed because the display is located behind the half mirror.

For this reason, a system using a new half mirror called a blazed half-transparent mirror (B1azed Half-Transparent Mirror) has been proposed for the purpose of reducing the size and weight. Line-of-sight matching display / imaging technology using half mirror (BHM), NTT
R & D, Vol. 43, no. 6, pp85-90, 1,
994).

FIG. 3 shows the blazed half mirror system. In FIG. 3, 1 is an observer, 32 is a blazed half mirror, 33 is a monitor, 34 is a camera,
35 is a mirror. In this method, an inclined half mirror is finely divided, a blazed half mirror 32 rearranged in a straight line is arranged on the entire surface of a monitor 33, and an image of an observer is reflected by the blazed half mirror 32 to a camera 34.
On the other hand, the display image on the monitor 33 is transmitted through the blazed half mirror 32 and can be observed by the observer 1.

As a method of performing display imaging in a time-division manner, a liquid crystal screen using a light-scattering type liquid crystal material and capable of electrically controlling the transmission / scattering state is used as a display screen. A camera that captures images with a camera installed in the area, displays a projection screen when scattered, and performs these imaging and display in a time-division manner (eg, Shiwa, Nakazawa, Komatsu, Ichinose: Eye-gaze matching technology for image communication) , NTTR & D, Vol.
1, pp 45-52, 1993).

FIG. 2 is a conceptual diagram showing the time division method. In FIG. 2, 1 is an observer, 22 is a liquid crystal screen,
Reference numeral 23 denotes a projector, 24 denotes a camera, and 25 denotes a circuit for controlling the camera 24, the liquid crystal screen 22, and the projector 23 in a time-division manner. Here, an image is taken by the camera 24 when the liquid crystal screen 22 is transmitted, and a screen is displayed by the projector 23 when the liquid crystal screen 22 is scattered.

The above-mentioned half-mirror method is mainly proposed for a desktop terminal device such as a videophone, and the time-division method using a liquid crystal screen requires a video conference system using a projection type display or a large screen display. It has been proposed as a system to do this.

[0016]

However, in the blazed half mirror method, when a blazed half mirror is manufactured, it is necessary to form a minute saw-tooth shape on a plate serving as a base material and to further perform a half mirror process. However, there are problems such as high cost, difficulty in mass production, and difficulty in cleaning because the surface is serrated. On the other hand, the time-division method using a liquid crystal screen requires a circuit or the like that is controlled in a time-division manner, and has the disadvantage that the entire system becomes expensive. Therefore, a low-cost display and imaging device with a simple configuration has been demanded.

[0017]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a light source and a display for displaying information to be displayed, and generates information to be displayed as light. A projector, a screen on which an observer observes a display image when light from the projector is irradiated, and an imaging device arranged at a position opposite to the observation position of the observer with respect to the screen to photograph the observer. Wherein the screen is provided with a hologram disposed on a transparent substrate and diffracting the light toward an observer. Things.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a conceptual diagram showing an example of the display and imaging device of the present invention. The case 5 includes a hologram 2, a camera 4, and a projector 3 as shown in the figure.
Then, the projector 3 is held in the case 5 so as to display an image on the surface of the hologram 2, and the camera 4 is housed inside the case 5, and the observation position of the observer 1 with respect to the hologram 2 so as to match the line of sight. It is installed and held on the opposite side. The camera 4 and the projector 3 are connected to a power supply and a signal line, respectively (not shown).

Here, the projector 3 has a light source and a display element as main constituent members. In this example, a commercially available liquid crystal projector uses a 12V 50W halogen lamp as a light source,
0.7 inch, 180,000 pixel TFT LC as display element
D, a liquid crystal projector constituted by F1.6 f = 20 mm was used as a projection lens. However, in order to improve the blur of the display image, it was modified so that the display element surface could be tilted. The camera 4 is also a commercially available video camera and is a 1/3 inch CCD 3 as an image sensor.
A plate-type camera having an autofocus function was used.
Although the projector 3 and the camera 4 both use commercially available products, the overall size is increased. However, if the projector 3 and the camera 4 are optimized so as to be suitable for the present example, the size can be further reduced, and the present invention is not limited to this.

The hologram 2 is formed by laminating a hologram photosensitive material on a substrate glass and arranging a recursive film on the back of the hologram.
It is produced by exposing a laser beam diverging from a point of 0 mm to a hologram photosensitive material vertically and exposing the same.
The oscillation wavelength of the laser beam used here is such that the hologram to be produced has an incident angle of 35 °, a diffraction angle of 5 °, and a central diffraction wavelength of 630 n.
m, 550 nm, and 475 nm, and light converted to spherical divergent light by a spatial filter was used. The center diffraction wavelength is determined in consideration of the spectral characteristics and intensity of the display light of the projector 3, the diffraction efficiency of the hologram, the half width, and the display color balance.

The hologram produced by the above method was sealed in a laminated glass (the laminated glass forms a screen). In this method, a hologram is attached to a glass surface, and another glass is laminated on the surface of the hologram via a laminated intermediate film such as polyvinyl butyral.

Then, the hologram 2 and the projector 3 sealed in the laminated glass are set so as to be at an incident angle of 35 °, and display light is emitted from the projector 2 to display a display image on the hologram 2. The image was formed so that the observer 1 could observe the display image by the projector 3 at an angle of 5 ° from the normal of the hologram 2.

Further, since the camera 4 is arranged on the opposite side of the hologram 2 on the extension that becomes the line of sight of the observer 1, the image of the observer 1 can be taken. The camera 4 is housed inside a case 5, and the inner surface of the case 5 is subjected to anti-reflection processing so as to reduce the reflection on the inner surface.

Two devices of this example are manufactured, and the output signal line of the camera 4 and the input signal line of the projector 3 are connected to each other, and two observers corresponding to each device are simulated like a videophone. As a result of the experiment, the face of another observer is recognized by the observer as a display by the display light emitted from the projector 3 to the hologram 2, while the observer can be captured by the camera 4, and the eye-gaze matching function is obtained. It was confirmed that it was a line-of-sight display imaging device that can be used in videophones and the like. At this time, since the real image of the diffusing surface was substantially recorded on the hologram 2 by spherical divergent light, a bright display was recognized by the observer, and the camera 4 installed on the back surface of the hologram 2 was not obstructive. Thus,
A good display and imaging device having a line-of-sight matching function was realized.

In the present embodiment, the angle of incidence and the angle of diffraction of the hologram 2 are determined as described above as a table-top type apparatus in which the apparatus is set on a desk, so that the observer 1 looks down slightly. The present invention can be changed as appropriate without being limited to the above, and can be changed in consideration of the installation method, the shape, the arrangement of the projector, and the like of the present apparatus.

A hologram usually has a size of several tens of mm to several tens.
It has an area of about 00 mm square, a thickness of about several μm to several tens of μm, and has a light diffraction function. In addition, a so-called hologram can be widely used, and a volume / phase hologram such as a Lippmann type can be used. Although it is desirable in that high diffraction efficiency can be obtained, holograms such as emboss type and rainbow type can also be widely used. As the hologram material, various photosensitive materials such as other photopolymers such as polyvinylcarbazole, gelatin dichromate, and silver salt can be used. The hologram 2 used in this example has a thickness of 20 mm.
μm, Lippmann type volume composed of acrylic photopolymer with an effective area of 105 mm length and 140 mm width.
It is a phase reflection hologram.

The size of the hologram is determined by the required size of the display image, the magnification, the system configuration and application, the laser output at the time of exposure, and the characteristics of the hologram photosensitive material. A larger area may be used, and several holograms may be adjacent to each other to obtain a large screen.

Although the hologram used in this embodiment is obtained by multiplex exposure of one color hologram with three colors, a plurality of holograms exposed by different lights can be superposed. But,
Considering the simplicity of the steps and man-hours, one hologram is preferable. Also in this case, it is preferable that the center diffraction wavelength of the hologram is matched with the spectral characteristics of the display light emitted by the projector in view of the color balance and brightness of the display image.

The specifications of the hologram are not limited to these, and various changes can be made according to the relationship between the hologram to be installed and the projector, such as the distance and angle. For example, a transmission hologram may be used instead of a reflection hologram as in this example. In this case, the positions of the projector and the camera are both on the back side of the hologram when viewed from the observer.

Further, during mass production of the hologram, a hologram to be a master is produced, and a hologram can be produced by duplication from the master hologram, so that mass production is good and the cost is low.

It is preferable that the hologram is used by being enclosed in a laminated glass in view of protection from external factors. Laminated glass is obtained by laminating and bonding a resin film such as polyvinyl butyral or polyurethane to at least one piece of glass. Examples of the form include glass / resin film, glass / resin film / glass, and the like.
Glass / resin film / resin substrate. The hologram may be sealed at the boundary between these glass or resin films. When the hologram is encapsulated in this manner, the hologram preferably has a small thickness, and the photopolymer used in this example is preferable.

The glass on which the hologram is mounted may be colored, or may be provided with an antireflection film or a black ceramic or the like on the surface to the extent that it does not hinder display, or may be colored on a resin film. Is also good. In addition, when the configuration of the present invention is used, glass is particularly preferable in terms of ease of cleaning and resistance to scratching, and it is most suitable for holding a hologram because it is less thermally deformed. When a similar configuration is adopted, a resin substrate may be used regardless of glass from the viewpoint of cost, weight reduction, and the like. Also in this case, it is preferable to seal the hologram between the two resin substrates with an adhesive or the like in view of protection from external factors. Furthermore, a combination of a resin substrate and a transparent resin film may be used, and the surface thereof may be colored, or a hard coat or an antireflection film for protecting the resin substrate may be added.

In addition, the projector may be provided with an optical member such as a concave mirror instead of the projection lens normally attached thereto, and in particular, a correction optical element such as a prism or a cylindrical lens for correcting the aberration of a display image. Various optical members serving as a system may be provided.

In this example, the display image is deformed because the display light is incident on the hologram at an angle of 35 ° from the projector. However, the deformation is corrected by incorporating a processing circuit for performing the deformation in advance. It is also possible to add left and right inversion processing. Although an actual videophone requires other signal processing circuits such as an encoding and decoding circuit, there is no problem in connecting them to them.

The observer is mainly a user of the apparatus, but can also be a target including all those who are present.

In the above description, the present invention has been described with a video phone in mind, but the present invention is not limited to this. For example, it can be used for a prompter, a game, and the like, and further used for a device in which a video printer is connected to the device of the present invention (a machine that is installed in a game arcade or the like and can take a photograph and seal it on the spot). The present invention is also applicable to a wide variety of display devices using holograms.

[0037]

According to the display and image pickup apparatus of the present invention, a good and inexpensive display and image pickup apparatus can be realized with a simple structure by using a hologram recording a real image of the diffusion surface of the diffusion plate. be able to.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an example of a display / imaging device of the present invention.

FIG. 2 is a conceptual diagram showing an example of a conventional display and imaging device.

FIG. 3 is a conceptual diagram showing another example of a conventional display / imaging device.

[Explanation of symbols]

 1: Observer 2: Hologram 3: Projector 4: Camera 5: Case 22: LCD screen 23: Projector 24: Camera 25: Time-division switching circuit 32: Blazed half mirror 33: Monitor 34: Camera 35: Mirror

Claims (3)

[Claims] 1. A projector having a light source and a display body for displaying information to be displayed, the projector generating information to be displayed as light, and a screen on which light is emitted from the projector so that an observer can observe a display image. And an image pickup device arranged at a position opposite to the observation position of the observer with respect to the screen and an image pickup device for photographing the observer, wherein the screen is provided on a transparent substrate. And a hologram for diffracting the light toward an observer. 2. The hologram according to claim 1, wherein a real image of a diffusion surface of a diffusion plate is substantially formed on a hologram photosensitive material, and this is used as an object wave, and the object wave and a reference wave are irradiated on the hologram photosensitive material. 2. The display and imaging device according to claim 1, wherein the hologram is a hologram manufactured by the following method. 3. The hologram according to claim 1, wherein a hologram photosensitive material adhered to a substrate has a recursive film disposed on one surface side of the hologram photosensitive material.
2. The display / image pickup apparatus according to claim 1, wherein the display / image pickup apparatus is a reflection type hologram on which an image of a diffusion surface is recorded by being irradiated with light from an exposure light source from the side opposite to the retroreflective film.