page 87
Digital Projection E-Vision Laser 4K Series
Reference Guide
CHOOSING A LENS
Rev A June 2017
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 2.22 - 3.67 : 1 
zoom lens.
3.  Check whether the lens covers the required throw distance. 
The focus range quoted for the 2.22 - 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 Appendix A 
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, 
see Full lens calculation in this 
section.
  For information about individual lens 
part numbers, see Appendix A at 
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
0.38 : 1 xed (UST) 0.82 m - 2.71 m
0.75 - 0.93 : 1 zoom 1.02 m - 12.7 m
0.76 : 1 xed 0.81 m - 5.08 m
1.25 - 1.79 : 1 zoom 1.33 m - 11.73 m
1.72 - 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