Digital Projection HIGHlite 740 1080p, Инструкция по установке и быстрому запуску, Страница: 91 / 157

page 82
Digital Projection HIGHlite 740 Series
Reference Guide
CHOOSING A LENS
Rev I February 2015
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 2.17 - 2.90 : 1
zoom lens .
3. Check whether the lens covers the required throw distance.
The range quoted for the 2.17 - 2.90 : 1 zoom lens is 2.7 - 15.4
m . The required distance of 11 m is within the range.
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.
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 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)