Precautions for Luxmeters
1 Photocells should use selenium (Se) photocells or silicon (Si) photocells with good linearity; they can still maintain good stability and high sensitivity after working for a long time; when E is high, choose photocells with high internal resistance, which have low sensitivity and good linearity , not easily damaged by strong light.
2. There is a V(λ) correction filter inside, which is suitable for the illumination of light sources with different color temperatures, and the error is small.
3. Add a cosine angle compensator (opalescent glass or white plastic) in front of the photocell because the photocell deviates from the cosine rule when the incident angle is large.
4. The illuminance meter should work at room temperature or close to room temperature (photocell drift changes with temperature
