Luminous intensity distribution describes a fundamental characteristic of luminaires including LED-based solid-state lighting (SSL) systems. A
goniophotometer is generally used to measure this property. A goniophotometer is a photometer for measurement of the angular dependence of optical quantities. It is applicable to acquire the luminous intensity distribution, luminous flux, spatial color distribution, and luminance distribution of lamps and luminaires. The latter two are proposed in recent years as the development of light & lighting. Combined with a spectroradiometer from Lisungroup, all spectral quantities such as color coordinates, color temperature and even color rendering index can be determined as a function of angle.