Video projection system

摘要

A video projector is used in target projection apparatus, for use with air defence training equipment, air traffic control training equipment, or other apparatus, where aircraft or other objects of interest (targets) are displayed on a large, normally spherical, projection screens. The projector incorporates a condenser for concentrating light from a source onto a liquid crystal display (LCD) panel. Zoom optics are arranged to receive and project light transmitted by the LCD panel onto the projection screen. The condenser itself includes a hollow body having an internal reflecting surface of revolution about an optical axis, the arrangement being such that light from the source entering the condenser is emitted as a beam within an emergent cone angle suited to the f-number of said zoom optics.