T3D Re: QD Technology

[Jim Crowell <crowell@xxxxxxxxxxxxxxx>]

At 6:59 AM -0800 1/29/98, john bercovitz wrote:
>At the poster session, Lowell Noble, founder, inventor and grand
>poo-bah of QD, had a demo next to my poster.  The basic price of
>the huge rear projection screen has dropped from 4K to 3K.

Interesting!  How big is "huge"?

There's another fellow in the lab who's also looking into rear-projection
materials, in his case for use with an LCD projector.  He showed me a
sample of some black stuff that some vendor had given him in response to a
question about how to make the background or "off" luminance
imperceptible...anyway, he said that the "gain" of this material was
supposed to be 0.8.  Since then I've seen a number of different material
gains, many well above 1, so it can't mean (as I originally thought) the
proportion of light transmitted.  So what does "gain" mean in this context?

>  I told
>him of my concern that Jim C would be having his subjects sit
>close to the screen and that there would therefore be too much
>light falloff at the edges.  He had a couple of things to say
>about that.  1) He controls the dispersion in manufacture to suit
>the use.  2) He offers an option of a full size fresnel lens
>behind the screen to take care of really wide angle viewing.  So
>he's really thought of everything.

Nifty!  Thanks John!

-Jim C.

----------------------
Jim Crowell
Caltech Division of Biology 216-76
1200 E. California Blvd.
Pasadena, CA 91125
Tel: (818) 395-8337
Fax: (818) 795-2397
jim@xxxxxxxxxxxxxxx



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