GG-11008 Edition 1.2
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6-3.3.2.4 Stimulus/background brightness check
Check the background intensity, stimulus intensity and stimulus size. The screen shows
background ON / OFF buttons and White / Yellow buttons on the left side, stimulus projection
position buttons at the center, the current stimulus intensity [dB] on the right side and the
stimulus intensity up/down arrow buttons at the right end.
Pressing a stimulus position button projects the stimulus to the related stimulus position. For the
stimulus intensity up/down arrow buttons, pressing a double-arrow button increases or
decreases the intensity by ±10dB and a single-arrow button increases or decreases the intensity
by ±1dB. The intensity range is 0 (brightest) to 50dB (darkest).
(1) Background intensity
Standards
Test procedure
Tools
Intensity at points B to E
10±1cd/m
2
(white)
100±10cd/m
2
(yellow)
Perform the test in a dark room or cover the dome
front side with a blackout curtain for the test. For
details, see the description below.
Intensity
meter
[1] Press Background ON and White to light the background lamp (white).
[2] Set the intensity to 0dB and press B to project the stimulus to point B.
[3] Using the projected stimulus, focus the intensity meter to point B.
[4] Leaving the intensity meter as it is, press C to move the stimulus to point C.
[5] Measure the background intensity at point B with the intensity meter and check that it
satisfies the standards.
[6] Repeat steps (2) to (5) above for points C to E and check that the values satisfy the
standards.
[7] Press Background Yellow to light the background lamp (yellow) and repeat steps (2) to (6)
above.
[8] Press Background OFF to turn off the background lamp (for checking the stimulus intensity in
(2)).
Figure 68 Stimulus/background brightness check
