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Digital Projection E-Vision Laser WQ120 Series
CHOOSING A LENS
Rev A May 2018
Basic calculation example
1. Calculate the throw ratio using the formula.
Your screen is
4.5 m
wide and you wish to place the projector
approximately
11 m
from the screen. The throw ratio will then be
11
4.5
=
2.44
2. Match the result with the lens table.
The lens matching a throw ratio of 2.44 is
the 2.34 - 3.90 : 1
zoom lens
.
3. Check whether the lens covers the required throw distance.
The focus range quoted for the 2.20 - 3.67 : 1 zoom lens is
2.36
- 24.2 m
. The required distance of 11 m is within the range.
Notes
The lens table shown on this page
includes High Brightness lenses
only. For a full list, see
at the end of this document.
The basic calculation on this page
does not take into consideration
DMD™ and image size, which could
affect the throw ratio. For a more
complex and realistic calculation,
in this
section.
For information about individual lens
the end of this document.
INFORMATION YOU NEED FOR THIS CALCULATION
•
The throw ratio formula:
Throw distance
Screen width
Throw ratio =
•
The lens table:
Throw ratios
Focus range
0.79 - 0.99 : 1 zoom
1.02 m - 12.7 m
1.32 - 1.89 : 1 zoom
1.33 m - 11.73 m
1.82 - 2.40 : 1 zoom
1.83 m - 14.9 m
2.34 - 3.90 : 1 zoom
2.36 m - 24.2 m
