Digital Projection POWER 2v, Руководство пользователя

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Optics
The lamp faces downwards onto a 'cold mirror' which directs the light beam into a
condenser. A prism then splits the concentrated beam from the condenser into red,
green and blue light using dichroic filters and directs the light onto separate
DMDs™. The images produced by the three DMDs™ are then combined by the
prism to form a full colour image and directed into the lens for projection.
The condenser is precisely aligned in the factory. If it is moved there could be a
reduction in light output and image display quality.
Lenses
There are seven lenses available for the POWER display projectors which cater for
all foreseen user requirements. The lenses are identified by their ratio of 'Throw
Distance' to screen width, where 'Throw Distance' is the distance the projector must
be positioned from the screen to display an optimum image (see B—4, Positioning
the Projector).
At present, there are four fixed ratio lenses available for the projector (1.27:1, 3:1,
5:1 and 7:1), two zoom lenses; 1.5:1 to 3:1 and 3:1 to 7:1 respectively and an
SVGA Ultra Wide Angle lens.
1.27:1 is the accurate ratio for the lens marked as 1.2 and this ratio should be
used for any calculations.
The lens required will be dependant on the size of the screen, the 'Throw Distance'
available and the aspect ratios of the images to be displayed. If unsure which lens
would best suit your requirements, consult your dealer.
Only use lenses specified in this manual or recommended by Digital Projection.
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Overview
OVERVIEW
LBV00018; Revision E - 28/01/98
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