On Wed, 26 Sep 2012 09:16:24 +0100, "N_Cook" wrote:

Adrian Jansen wrote in message
web.com...

On 25/9/2012 5:53 PM, N_Cook wrote:
Like the ink-jet printer nonsense. Loads of nominally working video
projectors around where the lamp has worn out after its 1000 to 2000
hours
and a complete new projector is a little more than the cost of a
replacement
discharge lamp .
Anyone done a conversion to high power LED emitter lamp? tips/pitfalls ?
Obviously a number of opto-coupler functions need fudging as well as
disconnecting the original lamp supply and HV ignitor sub-circuit
lamp supply input side optos , ignitor-on , lamp on, half/full
brightness
output side optos , ignitor cct ok, lamp on (drawing correct current)
confirmation
Perhaps should only consider projectors that allow colour temperature
setting within the menu structures
any other considerations?
I just saw reference to this LED lamp cluster , anyone sen the spec of
the
beam angle for it
http://www.ledengin.com/news-events/2012-08



More specs at http://www.ledengin.com/products/emitters/#LZ9

But 1300 lumens is still a long way from a typical video projector. eg
the NEC NP64 is supposed to put 3000 lumens on the screen, that includes
all the optical losses along the way.


--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Note reply address is invalid, convert address above to machine form.



I still cannot find the half-power beam angle. It 15 degrees fine but if 120
degrees then back to all the optics losses business


Due to the physics of the bare LED, about 45 to 60 degrees. With the
fancy lens maybe 20 to 30 degrees, but that is a WAG.

?-)