1. Safety
As described in "High Brightness precautions: Hazard Distance (HD)", page 8 , it is mandatory to create a restricted zone within
the beam areas closer than any NOHD. In th e enc losed projection area the combination of two restricted zones are relevant: T he
restricted zone of the projected beam toward the screen; taking into account 1 meter Separation W idth (SW ) from the beam onward.
Combined with the restricted zone related to the rear reflection from the s creen (HD
reflection
); also taking into account a 1 meter lateral
separation.
The HD
reflection
distance equals 25% of the difference between the determined HD distance a nd the projection distance to the rear
projection screen. To determine the HD distance for the used lens a nd projector mod el see graphs in chapter "HD in function of the
lens T hrow Ratio (TR)", page 11.
HD
reflection
= 25% (HD – PD)
The light emitted from the s creen within the observation shall never exc eed the RG 2 exposure limit, determined at 10 c m. The
HD
diffuse
can b e neglected if the m easured light at the sc reen surface is below 5000 cd/m² or 15000 LUX .
1.4.4 HD in function of the lens Throw Ratio (TR)
TR (T hrow Ratio)
The ratio of the distance to the screen (throw) to the screen width.
HD versus Throw Ratio
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0.4 0.8 1.2 1.6 2.0 2.3 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5 5.9 6.3 6.7 7.1 7.5 7.9 8.3 8.7 9.1 9.5 9.9
Hazard distance [m]
Throw Rao
F80-Q7, F80-4K7 F80-Ultra, F80-Q9, F80-4K9
Image 1-4
Graph shows Hazard Distance in meters versus Throw ratio of the lens
R5906852 F80 SERIES 21/09/2017
11