How to set up the correct light level with integrating sphere
The integrating sphere - like our spherical illuminator LE6 - has three holes in it:
- a big one for the TEST CHART
- a small one for the light entry from the LAMP
- and a third one where the LUXMETER is looking into the sphere
The luxmeter is set up in a way that the luxmeter shows the correct value if there is a test chart inserted in the test chart slot. This happens due to the fact that the glass plate of the chart reflects a lot of light back into the sphere. This light would be lost if there is no chart inserted. So the luxmeter is prepared in a way that it shows the value you would measure with an external luxmeter in a blank area of a test chart (this correction is done by the little COMPENSATION FILM you can see in front of the luxmeter-sensor).
If you want to measure directly on the chart you can take the sensor off the holder (a small clamp, pull the sensor carefully to the back side of the sphere) and measure directly on the chart. There is a small hole for the cable on the top of the front of the drawer.
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