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Digital Projection 0.38:1 E-Vision Ultra Short Throw Lens
Installation Guide
POSITIONING THE SCREEN AND PROJECTOR
Rev B June 2019
Positioning The Screen And Projector
Calculation
Positioning is determined by:
•
throw
- the distance between the projector and the screen, and
•
offset
- the distance between the ground and the bottom edge of the screen.
These figures are calculated using the screen width in millimeters, using the following formulae:
throw = screen width (in millimeters) x 0.35134 - 184 mm
WUXGA offset = screen width (in millimeters) x 0.2586 + 136 mm
4K-UHD offset = screen width (in millimeters) x 0.2515 + 136 mm
Notes
The lens should only be used on
flat surfaces and must be aligned
parallel to the screen.
The
throw formula
on this page
uses easy to measure reference
points: the screen surface and the
front of the projector. In reality the
throw is measured from a point
inside the lens which is 184 mm
away from the front of the projector.
Likewise, the
offset formula
uses
a correction of 136 mm because
in reality the offset begins 136 mm
above the ground.
The screen width must be in mm.
For screen widths below 2223 mm,
the rear of the projector is in line
with the screen wall. Space must
be left behind the projector for
ventilation: the minimum distance
should be 500 mm. For further
information, see the projector user
manual.
Lens tolerance can be up to 5%.
Offset is also dependent on lens
shift
Throw
Offset