The present invention relates to a display and image capture apparatus which enables eye contact between callers in a videophone, video teleconferencing or similar system.
With recent developments of telecommunication technology such as video coding techniques, a two-way visual telecommunication system which links remote places through a video and audio communication network, such as a videophone or video teleconferencing system, has rapidly come into wide use. It is now being expected that the two-way visual telecommunication will be able to offer images full of a sense of reality by the expansion of an integrated services digital network (ISDN) and broadening of the band of the transmission network therefor. FIG. 1 shows a display and image capture apparatus which is now employed in the two-way visual telecommunication. A video camera 3 is mounted on the top or one side of a CRT display or like display 1, the image of a user M captured by the video camera 1 is transmitted to a similar display and image capture apparatus (not shown) at a remote place and displayed on its display. In this instance, however, the user M of such an apparatus is usually looking at the display 1 on which the person he is talking to is being displayed, and hence he will not turn his gaze on the video camera 3. This results in a boring conversation between callers who do not look each other in the eyes, although their images can be transmitted with a sense of reality.
Methods which employ a half-transparent mirror (which may be referred to simply as HM) for enabling eye contact between callers are proposed in Japanese Patent Application Laid Open Nos. 269128/87 and 11082/90, for example. FIG. 2 shows the basic configuration for such methods. A half-transparent mirror 2 is disposed in front of the display 1. An image from a subject, i.e. the image of the user M is reflected by the half-transparent mirror 2 and is captured by the video camera 3 disposed above the half-transparent mirror 2. Consequently, the image-thus captured is equivalent to an image which is captured from the position of the display 1, and since the user's (i.e. talker's) eye is being directed toward the display 1, the eyes of the talker M and the listener being displayed on the display screen will meet. With such a configuration as depicted in FIG. 2, however, the size of the half-transparent mirror 2 increases with an increase in the size of the display screen of the display 1. This will also increase the depth D of the display and image capture apparatus, resulting in the apparatus inevitably becoming bulky.
In Japanese Patent Public Application Laid open No. 37890/90 there is proposed, as another method for enabling eye contact between callers, a configuration in which a mirror or half-transparent mirror having a number of parallel slits cut therein is disposed aslant in the same fashion as in the case of FIG. 2, in place of using the continuous half-transparent mirror. This is also defective in that the overall depth of a combined structure of the mirror and the display is large as is the case with the prior art example of FIG. 2. In this laid open application it is further stated that the depth is reduced by dividing the slit mirror into two and disposing them vertically, but in this case, since light reflected by the lower slit mirror enters the video camera through the upper slit mirror, a double image is captured; hence, this structure is impractical. In Japanese Patent Application Laid Open No. 209403/91 there is disclosed, with a view to reducing the depth of a projection TV set, a configuration wherein light from a projector provided at the lower part in the set is projected to a Fresnel mirror mounted on the ceiling of the set and the reflected light from the Fresnel mirror is projected onto the back of a screen mounted on the front of the set. Yet, this laid open patent application makes no mention of capturing the image of a person looking at the image on the TV display from the direction to meet his eye, and even if the Fresnel mirror replaces the aforementioned half-transparent mirror 2 in FIG. 1, the user M cannot see his image displayed on the display, because the Fresnel mirror is not half-transparent.
Thus, the conventional display and image capture apparatuses possess the shortcomings that no eye contact is enabled between callers or the apparatuses which enable eye contact are bulky.