In 1989, Eugene Dolgoff and his company Projectavision of New York won
a $1 million contract from the Pentagon to develop a new kind of video projector.
Dolgoff now promises a domestic version, the size of a shoe box, for around
$1000 (US patent 5 012 274).
Low-cost video projectors already exist. The image is formed by shining
light from a bright lamp through a small liquid-crystal screen, similar
to those used in pocket TVs. A lens then focuses an enlarged image onto
a screen.
The problem with this kind of projector is that the LCD panel is made
up of many individual cells, each switched on and off by a voltage supplied
through a transistor at the corner of the cell. The transistor and the insulating
strips needed to prevent one cell affecting its neighbours creates dead
space round each cell, or 鈥榩ixel鈥�, of the picture. This is very noticeable
when the image is blown up on a large screen.
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In Dolgoff鈥檚 system, light from the LCD is passed through an array of
mirrors, prisms or micro-lenses which create several replicas of the image.
These replicas are superimposed, but slightly offset so that they overlap
to fill the dead space between the cells.
