| How to choose a suitable integrating sphere and baffle?
The size of integrating sphere is determined by the dimension of light-source, from 0.2m to 2m are optional. And the inner material of sphere can be diffuse reflection, like BASO4 powder; the baffle must be done at the lowest degree. At the luminous test mode, the shape of lamp and spectrum type should conformity with the standard light-source as possible as it can. In practice, the diameter of sphere should be as 6 times as diameter of standard light-source. But if the condition is limited, it would be better that the shape of lamp and spectrum type should conformity with the standard light-source as possible as it can.
The material quality of inner sphere will make a big effect for the measurement. Thus we choose the white coating to make the reflection coefficient be the lowest, as the BaSO4 and MgSO4 have the features of good chemistry stability, not easily turn yellow.
The baffle will also affects the test precise; the baffle will stop the detector receiving the direct lights from the light-source, it would be better to choose a small one. Generally, the baffle should be put between photo-detector and light-source.
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