1. According to the reflectivity of the internal coating:
Note: It can select the coating according to the test requirement, the default is the BaSO4 coating.
2. According to the test method:
We don’t discuss both the integrating sphere and goniophotometer here, we only talk about integrating sphere.
Specification: The above requirements and instructions are based on a part of related standards of GB / T 24824 and the Energy Star requirements. So when we are choosing the integrating sphere, we should analysis the light’s emitting angle first , and then chose the test method, then we can select the appropriate size integrating sphere. (Please note that if you choose inappropriate integrating sphere, the error of test data, especially for the luminous flux parameters will have 5%~30% tolerance.
Test Methods are as follow:
2π Geometry: for downlight, spotlight, ceiling light, project light etc.
4π Geometry: for bulbs, corn light, candle light, T series tubes etc.
3. According to the tested lamp’s power/ size:
Generally, it will be better to adoption use big size integrating sphere for high power lamps test.
Generally for panel shape light source, the diagonal length of tested panel shape lamp should be less than 1/7 diameter of the integrating sphere(according to LM-79) .
For the linear light source, the maximum length should be less than 2/3 diameter of the integrating sphere(according to LM-79).