Appendix B: Choosing a lens
Digital Projection E-Vision Laser 15000 Series
Basic calculation
The basic calculation on this page
does not take into consideration
DMD™ and image size, which
could affect the throw ratio.See Full
lens calculation on page 115 for a
more complex and realistic
calculation.
When calculating the throw ratio,
be sure to use identical
measurement units for both the
throw distance and the screen
width.
See Choosing a lens on the
previous page for information about
individual lens part numbers
See Fitting a lens hood on page 23
for more information about using
the right lens and hood
1
2
Identify the required lens by calculating the
throw ratio
.
A
throw ratio
is the ratio of the throw distance
2
to the screen width
1
:
1. Use the formula above to obtain the required throw ratio.
2. Allow a tolerance of +/- 3% in the throw ratio calculation and match the throw ratio with a
lens from the table below:
Throw ratios
Focus range
0.377 : 1 fixed (UST) 0.82 m - 2.71 m
0.75 - 0.93 : 1 zoom 1.02 m - 12.7 m
0.76 : 1 fixed
0.81 m - 5.08 m
1.25 - 1.79 : 1 zoom 1.33 m - 11.73 m
1.73 - 2.27 : 1 zoom 1.83 m - 14.9 m
2.22 - 3.67 : 1 zoom 2.36 m - 24.2 m
3.58 - 5.38 : 1 zoom 3.8 m - 35.35 m
5.31 - 8.26 : 1 zoom 5.59 m - 54.8 m
3. Ensure the required throw distance is within the range covered by the lens.
Reference Guide
Rev B April 2021
page 113
Notes
