Abstract A system of video communication which allows the production of a graphic creation which can be transmitted by television receivers at some distance, comprises a projector which projects images on the bottom surface of a screen, through a partly reflective mirror. The image on the screen is fed through this mirror to photographic means which are connected with a storage, recording and/or reproduction system. The screen comprises a semi-transparent sheet which can be provided with a photosensitive coating. The image projected from below onto the screen is visible for an operator who can modify it from above the screen. Another embodiment of screen comprises a transparent lower sheet and a translucent upper sheet of distinctively different colors, with particulate material between them. Pressing with an instrument on the upper sheet displaces the particulate material and temporarily prints on the lower sheet the pressed image of the upper sheet. This system allows an animation of the projected images by their modification, and can be used for conferences, teaching, tests, etc.
A system of video communication, comprising a screen, means for projecting images on the screen from beneath the screen, the screen having one transparent lower surface adapted to transmit the images and one semi-transparent upper surface adapted to receive visible markings thereon with the aid of an implement held by a user of the system, opto-electronic means directed toward said lower surface of said screen to pick up from said screen a composite image comprised by the projected image and the added markings, and means for transmitting said composite image.
Claim 2
Independent Claim
90 words
A system of video communication, comprising a screen, means for projecting images on the screen from beneath the screen, the screen having one transparent lower surface adapted to transmit the images and one semi-transparent upper surface adapted to receive visible markings thereon with the aid of an implement held by a user of the system, opto-electronic means directed toward said lower surface of said screen to pick up from said screen a composite image comprised by the projected image and the added markings, and means for transmitting said composite image.
Claim 3
Dependent Claim
21 words
A system as claimed in claim 1, in which said transparent and semi-transparent surfaces are flat and parallel to each other.
Claim 4
Dependent Claim
27 words
A system as claimed in claim 2, in which said projector and said opto-electronic means have optical paths intersecting said surfaces at right angles to said surfaces.
Claim 5
Dependent Claim
44 words
A system as claimed in claim 3, and a partly reflective mirror disposed in optical paths, one of said optical paths being disposed at equal acute angles to the plane of said mirror, the other of said optical paths passing straight through said mirror.
Claim 6
Dependent Claim
91 words
A system as claimed in claim 1, in which said screen is comprised by a first transparent sheet on its lower side, a second semi-transparent sheet on its upper side, and a loose particulate material of a distinctively different color from said second semi-transparent sheet interposed between these two sheets and which can be pushed aside by pressure exerted by an implement held by the user, to permit these sheets to come into contact, thereby creating color-differentiated zones on the side of the transparent sheet which is opposite said particulate material.