Appendix A Optical Measurement Procedure - BenQ PB8250 Service Manual

Appendix A Optical Measurement Procedure

1. Scope:
This document describes critical optical related test definitions and Instructions for data or
video projectors. The other general terminologies are specified in ANSI IT7.228-1997.
2. General Requirements
1. The unit under test should be allowed to stabilize without further adjustment for a
minimum of 5 minutes, at nominal ambient room temperature of 25°C, before making
measurements.
2. Measurements shall take place in a light proof room, where the only source of
illumination is the projector. Less than 1 lux of the light on the screen shall be from any
source other than the projector.
3. All measurements shall be made on flat screens that do not provide any advantage to the
performance of the unit.
4. All measurements shall be made at standard color temperature setting, 100% white image
(per ANSI IT7.228-1997), except where noted.
3. Practical Requirements
1. When measuring contrast manually, operators should not wear white clothing since light
reflected from white clothing can influence the measurement.
2. Unless otherwise specified, the projection lens is set in the widest zoom position since
zoom function can influence the measurement.
3. Measurement should be performed with Minolta Chromameter, Model CL-100, or
equivalent.
A1. ANSI BRIGHTNESS
ANSI Lumens = (L1+L2+L3+L4+L5+L6+L7+L8+L9)/9 (lux) x A(m^2)
A (Area) = W * H (m^2)
W: width of projected image (m)
H: height of projected image (m)
6