Digital Projection E-Vision Laser 4K Series - Choosing A Lens

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Digital Projection E-Vision Laser 4K Series
Reference Guide
CHOOSING A LENS
Rev A June 2017
Choosing A Lens
A number of lenses are available. Which lens you choose depends on the screen size, image aspect ratio, throw distance and light output.
The following table shows all available lenses in order of their throw ratios:
Throw ratios Focus range Lens shift
0.38 : 1 xed (UST)* 0.68 m - 2.44 m Depends on image size, see UST Lens Installation Guide (separate document).
0.75 - 0.93 : 1 zoom 1.02 m - 12.7 m V: 0.5 (U) 0 (D) frame
H: 0.1 (L) 0.1 (R) frame
0.76 : 1 xed* 0.81 m - 5.08 m none
1.25 - 1.79 : 1 zoom 1.33 m - 11.73 m V: 0.5 (U) 0 (D) frame
H: 0.1 (L) 0.1 (R) frame
1.72 - 2.27 : 1 zoom 1.83 m - 14.9 m V: 0.5 (U) 0 (D) frame
H: 0.1 (L) 0.1 (R) frame
2.22 - 3.67 : 1 zoom 2.36 m - 24.2 m V: 0.5 (U) 0 (D) frame
H: 0.1 (L) 0.1 (R) frame
3.58 - 5.38 : 1 zoom* 3.8 m - 35.35 m V: 0.5 (U) 0 (D) frame
H: 0.1 (L) 0.1 (R) frame
5.31 - 8.26 : 1 zoom* 5.59 m - 54.8 m V: 0.5 (U) 0 (D) frame
H: 0.1 (L) 0.1 (R) frame
Lenses marked with an asterisk (*) above are only available for High Brightness projectors. All other lenses have High Contrast counterparts.
To choose a lens, calculate the throw ratio required.
Notes
Throw distance calculations are
based on the distance from the outer
end of the lens, which will vary from
lens to lens.
The distance between the front
of the projector chassis and the
outer end of the lens is called lens
extension. Lens extensions is
measured when the lens is focused
at innity, and fully extended.
Refer to the projector CAD drawings
for individual lens extension gures.
The 0.38 : 1 xed lens has no
adjustable shift value. However,
the lens has an inherent offset
depending on image size. See
the UST documentation published
separately on the Digital Projection
website.
The 0.75 - 0.93 : 1 zoom lens has
an additional feature permitting
barrel correction for curved screens.
The front ring of the lens is a
manual control which provides focus
curvature adjustment to correct for
the different focal distances between
center and corner.
Throw ratios of High Contrast
lenses differ slightly from their High
Brightness counterparts. For details,
see Appendix A at the end of this
document.
For information about individual lens
part numbers, see Appendix A at
the end of this document.