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Sensor Distance
The measurement method used in the Viso systems is called “far field”, which means
that the distance between the measuring light source and the sensor should be at
least 8 times the diameter/length of the light source as shown below.
According to CIE S 025/E:2015, minimum measuring distances should be (D is the
largest dimension of the luminous area):
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Beam angle ≥90° (in all measurement planes):
≥5xD
(Viso Systems ≥8xD)
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Beam angle ≥60°:
≥10xD
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Narrow angular distribution / steep gradients:
≥15xD
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Large non-luminous areas with maximum distance S:
≥15x(D+S)
Please note that “light source diameter/length” is only the illuminated part of the
luminaire!
