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Andrew McCrea

"I'm Not Bad, I'm Just Drawn That Way!" - Jessica Rabbit
 

A directional gain screen needs to be curved, such that the light is reflected toward the center of the audience. This can best be done by "ray tracing", or following "rules of thumb" such as SMPTE Recommended Practice RP95. A gain screen installed flat will tend to be difficult to light uniformly, especially where the throw is short and the audience is seated close to the screen.

A really deep curved screen like the D-150 or Cinerama systems used needs to be designed carefully (e.g., Cinerama "strip screen") to avoid cross-reflections. They also tend to have much more of a "sweet spot" for optimum viewing, with objectionable geometric distortion outside of the "sweet spot".

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John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion