JP3171955B2 - Display imaging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display / image pickup apparatus suitable for a video conference or the like, and more particularly, to a display / image pickup apparatus capable of making a conversation as if in a real space while keeping the eyes of the persons who interact with each other. Things.

[0002]

2. Description of the Related Art Conventionally, a video conference system has been constructed and put to practical use in remote location communication and the like. In the general display and imaging device used for this, the position of the display surface and the video camera are different, so if you look at the display surface displaying the image of the other party, your eyes will be directed to the display surface instead of the video camera. In this case, an image with a deviated gaze is captured and displayed on the display surface of the other party. For this reason, the viewer sees display images whose eyes are deviated from each other.

[0003] In television broadcasting, when an announcer of a television station reads news, the eyes of the announcer are often displaced from the lens surface of the television camera and look at a manuscript or a display image placed on a desk. At this time, when the viewer views the video of the face of the announcer through the television, the eyes of the announcer do not match.

Therefore, in television broadcasting, a display imaging device having a half mirror arranged in front of a display surface of a display image or the like is used in order for a news announcer or the like to match a line of sight with a viewer. In this display imaging device, a half mirror is disposed obliquely in front of the display surface, and a display image or the like is viewed obliquely through the half mirror from the display surface. Due to the oblique arrangement of the mirror, the mirror is bent in a direction different from the display surface direction and guided to the video camera. For this reason, it is possible to match the line of sight between the display image and the captured image.

On the other hand, as shown in FIG. 6, a screen 1 is used as a display surface of a projected image, and a liquid crystal / polymer composite sheet or the like is used for the screen 1 to control the transmission / scattering state in a time-division manner. An apparatus in which a projector 2 and a video camera 3 are installed on the back of a screen 1 has been proposed. The screen 1 is controlled to be in the scattering state during the projection display period of the projector 2, and is controlled to be in the transmission state between the projection display period and the next projection display period, so that the image of the subject 5 is transmitted.
The imaging by the video camera 3 is enabled. here,
By arranging the projection optical axis 7 of the projector 2 on the same axis as the incident optical axis 8 of the video camera 3, the interrogator 5 of the display / imaging apparatus matches the line of sight with the interlocutor of the projection image displayed there. be able to.

[0006]

As described above, in a conventional general video conference system, a conversation is performed while viewing images whose eyes do not match with each other. Because it was a conference between distant places, it was considered unavoidable that lack of presence was unavoidable.

In a television broadcast, in a display / image pickup apparatus in which a half mirror is arranged in front of a display surface used by a news announcer or the like to match the line of sight with a viewer, the half mirror is inclined with respect to the display surface. Because of the arrangement, when the display surface becomes large, the volume occupied by the half mirror becomes large. Therefore, this line-of-sight matching method using a half mirror can only be applied to relatively small devices.

On the other hand, a screen which can be in a transmission state when shooting and a scattering state when displaying an image is applied to the display surface, and a gaze matching method using the display and imaging apparatus shown in FIG. In this case, since the projector 2 and the video camera 3 are arranged on the same optical axis, the optical path of a projected image or a photographed image generated by the mutual arrangement is obstructed, and a part of the displayed image becomes a shadow of the video camera 3. However, when the positions of the video camera 3 and the projector 2 are exchanged with respect to the screen 1, there is a problem that the shadow of the projector 2 is reflected in a part of the captured image. Therefore, it is conceivable to arrange the projector 2 and the video camera 3 as close as possible and in parallel as in the display / imaging device in FIG. 7. However, since the projector 2 and the video camera 3 have a specific volume, It is not easy to align the optical axes 7, 8 with each other.

As described above, even if the display and image pickup apparatus shown in FIGS. 6 and 7 is applied, the projection optical axis of the projector 2 with respect to the screen 1 and the incident optical axis of the video camera 3 can be brought close to each other even if they can be brought close to each other. Cannot be performed, and depending on the arrangement positions of the video camera 3 and the projector 2, the video camera 3 partially obstructs the projected image of the projector 2 or the projector 2 partially obstructs the image captured by the video camera 3. Gaze matching was insufficient. Furthermore, when the screen 1 is made transparent during shooting, there is a drawback that the high-luminance light-emitting portion (light source, light-emitting body, etc.) of the projector 2 can be seen by an interlocutor, and the optical axis is shifted. Gaze matching was insufficient from the point of view.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a display space in which the eyes of the interlocutors can be matched with each other through good images, and the user can enjoy the sense of interacting in the same place. An object of the present invention is to provide a display and imaging device that can be realized.

[0011]

In order to achieve the above object, a display and imaging apparatus according to the present invention comprises a screen for displaying a projected image, a projector for projecting and displaying an image on the screen, and a rear surface behind the screen. be those with a video camera for photographing a subject of the screen front Te, especially the distortion correction in inverted trapezoid distortion correction circuit before displaying an image such as a cathode ray tube or a liquid crystal panel is an image display of the projector performs processing, the projector is disposed obliquely rearward with respect to the screen, when the optical axis of the video camera is arranged perpendicular to the screen
In both cases, the screen is always semi-shielded against oblique incident light.
Has light or scattering properties and transmits at normal incidence
A screen that always has the characteristics
A mask that changes the light transmission state during the shooting and the light blocking state during the shooting period
It is provided between the projector and the screen
And

[0012] Or , in particular, image display of a projector
Displaying images on the body, such as a CRT or LCD panel
Before performing distortion correction processing with an inverted trapezoidal distortion correction circuit,
The projector is positioned diagonally behind the screen and
Make the optical axis of the video camera perpendicular to the screen
With such an arrangement, the screen is a screen that always has a semi-shielding property or scattering property for obliquely incident light, and has a transmission property for normally incident light,
Screen that is non-reflective on the front and back of the screen
Alternatively, the screen is characterized by being subjected to a non-reflective surface processing .

[0013]

[0014]

According to the present invention, half of the oblique incident light is always
Has light-blocking or scattering properties, and is
By using a screen with constant transmission characteristics,
The projector is arranged on the back diagonally behind the screen to display the projected image at the same time as Ru to <br/> to allow image projection on a screen, to lay vertically video camera to the screen, each other projector and video camera To prevent interference of the optical path of the projected image or captured image caused by the arrangement of the projector, and to match the line of sight of the interlocutors by matching the optical axis of the projection with the optical axis of the shooting on the screen surface, and by oblique projection, The high-intensity light source or illuminant of the projector is prevented from entering the interlocutor on the front of the screen.

At this time, the trapezoidal distortion of the projected image on the screen caused by the projection from the rear side of the screen obliquely from the rear side is inversely corrected in advance by the image processing of the inverse trapezoidal distortion correction circuit so that the correct image is displayed on the screen. To

Further, a mask provided between the projector and the screen is only shielding state imaging period of the video camera, preventing child transmission of light sources in projectors at the time of shooting
Or by the screen
Screen or a surface with a non-reflective surface treatment
By using the clean , the reflection on the video camera is prevented, so that an even cleaner and better photographed image can be obtained.

[0017]

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

FIG. 1 is a block diagram showing an embodiment of a display and imaging apparatus according to the present invention. Display imaging apparatus 10 according to the present embodiment
Is a screen 1 for displaying a projected image, and a screen 1
2 for projecting and displaying an image on a screen, and a screen 1
And a video camera 3 arranged behind the rear surface of the projector 1 to capture an image of a subject in front of the screen 1. An image to be displayed on a projector image display such as a cathode ray tube or a liquid crystal panel in the projector 2 is corrected through an inverse trapezoidal distortion correction circuit 4 in advance. Then, the projector 2 can be disposed diagonally behind the screen 1 so that the projected image of the projector 2 can be displayed normally even when projected obliquely onto the screen 1,
The video camera 3 is arranged so that the incident optical axis of the video camera 3 is perpendicular to the screen 1. This
Here, the screen 1 is always partially shielded from oblique incident light.
It has light or scattering characteristics and is always
The screen described below having time transmission characteristics is used. An image of the video camera 3 capturing the interlocutor 5 in front of the screen 1 is guided to the projector 2 of a display and imaging device having the same configuration and located at another point.

First, the configuration and function of the inverted trapezoidal distortion correction circuit 4 in the configuration of FIG. 1 will be described.

When the projector 2 is projected obliquely onto the screen 1, when the distance a between the image display and the lens in the projector 2, the distance b between the lens and the screen 1, and the focal length f of the lens, Newton's formula 1 / a + 1 / b From = 1 / f, the graphic on the video display is projected with a large magnification at a position far from the lens on the screen 1, and is projected with a smaller magnification at a position near the lens. Therefore, when the graphic on the video display is, for example, a square, it becomes trapezoidal on the screen. Therefore, the inverse trapezoidal distortion correction circuit 4
When a video signal is processed into an inverted trapezoid and displayed on a video display body, for example, when a square video signal is input, a correct square figure can be displayed even on the screen 1 arranged diagonally.

The inverted trapezoidal distortion correction circuit 4 having such a function can be realized by using the following processing means. That is, the processing means for the horizontal direction of the input video signal compresses the start time and the end time between the video displays toward the center of the video display period based on the center of the horizontal video display period. Processing is performed so that the size becomes smaller as scanning is performed in the vertical direction (lower side direction).
Furthermore, the processing means for the vertical direction compresses the horizontal image on the upper side toward the lower side, and reduces the compression ratio toward the lower side. As a specific example, when a video signal is written as data in the frame memory, the video signal is complemented and written in the horizontal direction by the pixel clock and in the vertical direction by the number of horizontal synchronization signals. When reading this from the frame memory, the correspondence between the horizontal address and the pixel clock is changed according to the degree of compression, and the correspondence between the vertical address and the number of horizontal synchronization signals is changed. In other words, in accordance with the complementation of the number of pixel clocks and the number of horizontal synchronization signals, the compression part stops the complementation of the address of the frame memory, or skips the address and supplements the data to read data from the frame memory. realizable.
As a result, the image is displayed on the video display body after the inverse trapezoid correction in which the upper side and the lower side are parallel. When the relationship of the oblique arrangement of the projector 2 with respect to the screen 1 is rotated by 90 °, when performing the above-described inverted trapezoidal distortion correction, the above-described horizontal and vertical may be exchanged and corrected.

In the display and image pickup apparatus of the present embodiment, before the video signal of the video camera 3 is input to the projector 2 in the display and image pickup apparatus arranged at another point, the image signal passes through the inverse trapezoidal distortion correction circuit 4 and is projected obliquely by the projector 2. By canceling the trapezoidal distortion due to oblique projection in advance, and always semi-shielding characteristic or oblique incident light
By using the screen 1 having a scattering characteristic, the projector 2 can be arranged obliquely with respect to the screen 1. At the same time, screen 1 is
, The video cameras 3 can be arranged perpendicularly to the screen 1 without making their optical axes coaxial with each other. Of the video camera 3 and the optical axis of the video camera 3 is perpendicular to the screen 1 so that the interlocutor 5 watching the projected image can be photographed from the front, and the eyes of the interlocutors can be matched. it can. Further, the optical axis of the projector 2 is set to the interlocutor 5 in front of the screen.
, The light from the high-luminance light source or the light-emitting body of the projector 2 does not directly enter the interlocutor 5.

Next, the configuration of the screen according to the embodiment of the present invention will be described. As described above , the screen 1 needs to be in a semi-light-shielded state or a scattered state in order to view the projected image light obliquely projected by the interlocutor 5 of the display imaging apparatus as an image on the screen. In order to shoot the interlocutor 5 with a certain video camera 3, it is necessary to be in a transparent state.

[0024] is to use the viewing angle dependent scattering plate screen for this condition is satisfied, Ru a plate having or transmitted by an incident angle of the incident light, the property of scattering. Specifically, for example, black fine silicone rubber strips are arranged in parallel in a transparent silicone rubber,
VC (View Control) of Shin-Etsu Polymer Co., Ltd.
L) Toka film by photocuring certain <br/> acrylate les over preparative special condition called phase separation photopolymerization film,
By constituting the membrane of a specific phase separation structure, the sheet (Polymer Prep that light incident on the polymer film becomes opaque to Rigara <br/> focal transmitted by the incident angle
prints, Japan, Vol. 38, no. 10,
1989). The transmission / scattering of the viewing angle-dependent scattering plate changes depending on the incident angle of light, and the transmission / scattering state does not change with time as shown in the timing chart of FIG. It should be noted that t in the drawing indicates the passage of time (the same applies hereinafter).

[0025] against the embodiment of the present invention, the scree
As satisfying the condition of emission, there is a plate having a property of varying in time the transmission state and the scattering state, this Reference Example
It may be used to screen and. Specifically, for example,
A liquid crystal / polymer composite sheet, in which a nematic liquid crystal is formed into a water-based emulsion in a front and back film processed with a transparent conductive film, and the periphery is covered with a polymer, and then water is removed. This is a sheet produced by, for example, dissolving a nematic liquid crystal in a monomer or the like by changing the phase with heat or a solvent and then polymerizing the monomer. At this time, the refractive indices of the liquid crystal and the polymer are aligned, and the voltage of the transparent electrodes of the sheet is controlled to align the liquid crystal molecules between the transparent electrodes in the direction of the electric field, so that the incident light in the normal direction of the sheet is transmitted. On the other hand, by not applying an electric field, the liquid crystal molecules are randomized, and light incident on the sheet in all directions is scattered. Therefore, a plate having such a property that it can be temporally controlled to a scattering state and a transmission state is used for the screen 1, and as shown in the timing explanatory diagram of FIG. Synchronously, the screen 1 is scattered to enable display, and the screen 1 is controlled to be in the transparent state in synchronization with the video camera 3 shooting period to enable shooting.

[0026] Incidentally, when having a property screen for displaying the projected image is reflected in the screen, or when <br/> between transmissive / scattering state unchanged viewing angle dependent scattering plate of the present embodiment,
When using any of the plates having the property of changing to the transmission state and the scattering state with time in the reference example , a mask 6 may be provided between the projector 2 and the screen 1 as shown in FIG. As shown in the timing charts of FIGS. 4 and 5, the mask 6 is time-divisionally controlled in synchronization with the shooting time of the video camera 3, and the mask 6 is turned on during the shooting period of the video camera 3 (when the shutter is opened). In the light blocking state, the mask is in the transmitting state during the period when the projected image is displayed on the screen,
The shutter of the video camera 3 is closed.

[0027] In the present embodiment using the visual angle-dependent scattering plate, but has reached constantly image of an object to the video camera 3 as shown in FIG. 4, shooting of the video camera 3 is projected light of the projector 2 This is performed only during the period when the light is blocked by the mask 6. Therefore, the reflection image of the projected image on the screen 1 and the reflection image of the high-intensity light source or illuminant of the projector 2 (for example, the light source section in the case of a liquid crystal projector, the CRT illuminant in the case of a CRT projector) are taken together with the image of the subject. There is no input to the video camera 3. further,
When a projected image or a high-intensity light source or luminous body is projected on the screen 1, the video camera 3 captures the image even if the captured image transmitted through the screen 1 is turbid due to scattering inside the screen 1. At this time, since the projection image or the light of the high-intensity light source or the light-emitting body is not projected on the screen 1 due to being masked, a clean photographed image without turbidity can be photographed.

[0028] In the reference example using a plate having a property of changing between transmissive state and a scattering state when, combined transmission / scattering of the shutter opening and closing the screen 1 of the video camera 3 as shown in FIG. 7 Since the opening / closing of the mask 6 (transmission / light blocking) and the opening / closing of the shutter are in opposite phases, the opening / closing of the mask 6 (transmission / light blocking) is scattering / transmission of the screen 1.
Therefore, as in the case of the present embodiment , the reflection image of the projected image on the screen 1 and the reflection image of the high-intensity light source or luminous body of the projector 2 are not input to the video camera 3 together with the photographed image.

Next, the projector of this embodiment will be described. As described above, a cathode ray tube (CRT bulb), a liquid crystal panel (LCD bulb) paired with a light source unit, or the like can be used as the image display of the projector 2. The projector 2 projects and forms an image of such an image display on the screen 1 by a lens. Here, when the screen 1 is arranged obliquely with respect to the projector 2, depending on the degree of the oblique angle, it may not be possible to focus the entire projected image only by the depth of focus of the lens. As a solution at this time, for example,
What is necessary is just to incline the image display body slightly at an inclination opposite to the inclination of the screen 1 across the main plane of the lens (the plane of the lens center orthogonal to the optical axis). In addition, diagonal screen 1
Above, the part closer to the lens surface is brighter than the farther part. To prevent this, if necessary, for example, CR
In the case of a T-bulb, it is displayed with a brightness distribution gradient,
In the case of a CD valve, an optical light intensity correction process such as providing a reflectance gradient on the light source reflector or placing a filter with a transmittance gradient on the light source light path may be performed.

In the embodiment of the present invention, the projector 2 is projected on the screen 1 from obliquely above. However, the projector 2 is arranged diagonally below and obliquely laterally to perform oblique projection. The trapezoidal distortion generated in the projected image at that time is processed by the inverted trapezoidal distortion correction circuit in the same manner as in the above embodiment.

In the above-described embodiment of the present invention, the inverted trapezoidal distortion correction circuit is arranged at the input portion of the projector. However, in particular, the circuit may be arranged at the output portion of the video camera. It is clear that either configuration is possible as long as it is arranged between the video camera and the projector at another point.

When the screen displaying the projected image has the property of being reflected, the mask 6 is used so that an unnecessary reflected image does not enter the video camera at the time of photographing. A mask may not be required if a surface treatment is performed so that reflection is not performed on the front and back surfaces of the screen, the front and back surfaces of two polycarbonate films, and the front and back surfaces of a transparent conductive film.

Furthermore, it is necessary to cut off transmission / light at a switching speed of several ms or less for each field period of a video signal as a mask in the present invention, so that durability, high speed, light transmission, and light scattering ( It is required to have excellent characteristics of light blocking. For example, in addition to the liquid crystal / polymer composite sheet described in the description of the screen, a ferroelectric liquid crystal plate or the like can be given.

[0034]

As described above, in the display / image pickup apparatus of the present invention, the projector for projecting an image on the screen is disposed obliquely rearward with respect to the screen surface and projects obliquely on the screen. The high-intensity light source or illuminant light of the projector does not directly enter the viewer who views the image, and the trapezoidal distortion of the projected image caused by oblique projection is processed in advance by the inverse trapezoidal distortion correction circuit to eliminate distortion. You can see the projected image.

Further, since the projector can be arranged obliquely rearward on the back side of the screen, the video camera can be arranged vertically rearward on the back side of the screen, so that the optical path of the projected image or the photographed image caused by the mutual arrangement is prevented. Can work. Therefore, by arranging the optical axis of the video camera perpendicular to the screen, an interlocutor looking at the screen is photographed from the front, and this photographed image is displayed on the present display imaging device installed at another point. Then, since the distortion is corrected even when the image is projected obliquely by the projector as described above, the image is projected perpendicularly to the screen from the direction of the video camera, and the image and the line of sight of the interlocutor can be matched.

Further, by using a mask that can be time-division control the light shielding state to the shooting period between the projector and the screen, or free at the surface and the back surface of the screen
Reflective screen or non-reflective surface treatment
By using the screen, input of an unnecessary image to the video camera due to reflection of a display image or the like projected on the screen can be prevented, and a good captured image can be obtained.

As described above, it is possible to realize a display / image pickup apparatus which has a large-sized display unit and which enables a highly realistic line-of-sight matching without a dead space such as a half mirror in front of the display unit.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention.

FIG. 2 is a diagram for explaining operation timing when a viewing angle dependent scattering plate is applied to the screen of the above embodiment.

FIG. 3 is a diagram for explaining an operation timing when a plate having a property of changing to a transmission state and a scattering state with time is applied to a screen as a reference example of the present invention;

FIG. 4 is a view for explaining operation timing when a viewing angle dependent scattering plate is used for the screen of the above embodiment and a mask is applied between the projector and the screen.

FIG. 5 illustrates a timing of an operation in a case where a plate having a property that changes with time in a transmission state and a scattering state is used for a screen and a mask is applied between the projector and the screen as a reference example of the present invention . Figure

FIG. 6 is a configuration diagram of a conventional display / imaging device.

FIG. 7 is a diagram illustrating a problem of a conventional display / imaging device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Screen 2 ... Projector 3 ... Video camera 4 ... Inverted trapezoidal distortion correction circuit 5 ... Interactor and subject 6 ... Mask 7 ... Projection optical axis of projector 8 ... Incident optical axis of video camera 10 ... Display and imaging device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-196696 (JP, A) JP-A-4-145788 (JP, A) JP-A-4-96581 (JP, A) JP-A-4-96581 94268 (JP, A) JP-A-2-228893 (JP, A) JP-A-4-323974 (JP, A) JP-A-6-113296 (JP, A) JP-A-6-30406 (JP, A) JP-A-4-280582 (JP, A) JP-A-4-81089 (JP, A) JP-A-4-42679 (JP, A) JP-A-3-80683 (JP, A) JP-A-2-76485 JP-A-2-7085 (JP, A) JP-A-1-172939 (JP, A) JP-A-62-1390 (JP, A) JP-A-56-58371 (JP, A) Sho 55-4192 (JP, A) Japanese Utility Model Application Hei 2-47638 (JP, U) Tokuhyo Hei 3-503939 (JP, A) (58) Fields surveyed (Int. Cl. H04N 7/10 H04N ^7/ 14-7/173 H04N ^7/ 20-7/22

Claims (2)

(57) [Claims] 1. A display / imaging apparatus comprising: a screen for displaying a projected image, a projector for projecting and displaying an image on the screen, and a video camera arranged behind the rear surface of the screen and photographing a subject in front of the screen.
An inverse trapezoidal distortion correction circuit that performs inverse trapezoidal distortion correction before displaying an image on the image display body of the projector, the projector is disposed obliquely behind the screen, and the optical axis of the video camera is positioned with respect to the screen. a display imaging device arranged perpendicular Te, the screen
However, it always has a semi-light-shielding property or scattering
That always have transmission characteristics for vertically incident light.
Clean and transparent during the projection display period,
A mask for setting a light blocking state during a photographing period
Display / imaging device characterized by being provided between screens
Place . 2. A screen for displaying a projection image and the screen.
A projector for projecting and displaying an image on a screen and the screen
The back of the screen to capture the subject in front of the screen.
A display and imaging device comprising a video camera for shadowing ,
Reverse before displaying the image on the image display of the projector.
An inverted trapezoidal distortion correction circuit for performing trapezoidal distortion correction;
A projector is arranged diagonally behind the screen,
Make sure that the optical axis of the video camera is perpendicular to the screen.
A display and imaging device arranged as described above, wherein the screen has a semi-light-shielding property or a scattering property for obliquely incident light, and a screen that always has a transmission property for vertically incident light, and No screen front or back
Reflective screen or non-reflective surface treatment
A display / imaging device, which is a screen .