Goniophotometer
A goniophotometer is a system to measure the luminous intensity of the source (or illuminance from the source at a given distance) in many different directions from the source. Compared with the sphere method, the goniophotometer method is theoretically free from errors due to differences in intensity distribution of the light source under test. It is applicable to acquire the luminous intensity distribution, luminous flux, spatial color distribution, and luminance distribution of lamps and luminaires.
