Plastic lenses (was Taylor-Merchant stereoscope lenses)

[P3D Jim Roberts <xjim@xxxxxxxxxxxxxxxx>]

I'm not an optical designer, but I pay one on TV - er, what
I meant to say is that I have a friend who is an optical 
designer, and though I have no technical details, I believe 
it is now possible to get plastic lenses that have the optical 
quality of the double element achromats.  The additional 
degrees of freedom come from 'optical surfaces' on the lens.

This is not the exact explanation, but if you think of a Fresnel
lens etched onto the surface of a spherical lens, you get the 
general idea.  Right now, they are horribly expensive, and used
in military applications and other things where money is no 
object, but I assume that the potential exists for very cheap,
very good, mass produced lenses.

Well, back to lurking . . .

Jim


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