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Old 04-12-2013, 11:20 AM
Eric H's Avatar
Eric H Eric H is offline
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Join Date: Jun 2002
Location: So. Calif
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Quote:
Originally Posted by cwmoser View Post
BTW, you mentioned the Fresnel Lens Screen - can you tell me more about it
as compared to the screen in the Philco 48-2500.
Carl
Hi Carl, The main difference between the Philco and the RCA is the Philco is a front projector and the RCA is a rear projector.


The RCA screen is a flat sheet of translucent Plastic with a series of fine concentric rings molded into it to amplify the light.
Wiki has an article about how Fresnel lenses work.

The Philco uses a sheet of Stainless Steel mounted so it's forced into a slight parabolic shape.
It has fine vertical grooves cut into it and is coated with a Lacquer type coating that contains microscopic glass beads to reflect and disperse the light hitting it.
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