On Fri, 27 Sep 2013 19:56:58 +0100, N_Cook wrote:

All the discharge lamps in video projectors , I/ve seen have an
electrode and squashed , not optically conductive glass, axial exactly
in line to where you want the light to go.

True. However, the lamp I was replacing originally looked like these:
http://www.porters.com/general-accessories/projector-bulbs/projector-studio-bulb-dyh.html
http://www.porters.com/general-accessories/projector-bulbs/eys-projection-lamp.html

Note that some LED projectors use RGB LED's with three PWM modulators
to control the output level of each color LED in order to get a better
looking "white". In particular, the micro DLP projectors use RGB
LED's. Some use white LED's but methinks they look awful on the
screen.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
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