Digital Projection HIGlite 8000 Series, Руководство пользователя

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Digital Projection
HIGHlite 8000 Series
CHOOSING A LENS Reference Guide
45 Rev F July 2014
Choosing a lens by calculation
Basic calculation
Identify the required lens by calculating the throw ratio .
A
throw ratio
is the ratio of the throw distance to the screen width:
Throw distance
Screen width
Throw ratio =
1. Use the formula above to obtain the required throw ratio.
2. Match the throw ratio with a lens from the table below:
Throw ratios Throw distance range
0.77 : 1 fixed lens 1.3 - 2.5 m (4.3 - 8.2 ft)
1.16 : 1 fixed lens 1.4 - 6.2 m (4.6 - 20.3 ft)
1.45 - 1.74 : 1 zoom lens 1.8 - 9.3 m (5.9 - 30.5 ft)
1.74 - 2.17 : 1 zoom lens 2.2 - 11.8 m (7.2 - 38.7 ft)
2.17 - 2.90 : 1 zoom lens 2.7 - 15.4 m (8.9 - 50.5 ft)
2.90 - 4.34 : 1 zoom lens 3.6 - 22.5 m (11.8 - 73.8 ft)
4.34 - 6.76 : 1 zoom lens 5.5 - 35 m (18 - 115 ft)
3. Ensure the required throw distance is within the range covered by the lens.
Notes
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.
When calculating the throw ratio, be
sure to use identical measurement
units for both the throw distance and
the screen width.
For information about individual lens
part numbers, see Appendix A at
the end of this document.
1
2
1
Screen width
2
Throw distance
DMD width
Image width in pixels
Throw ratio factor =
Throw distance
Screen width x Throw ratio factor
Throw ratio =