Correlated colour temperature changes of the LED sources depending on the angle of their radiation

Abstract

The aim of the report is a description of an issue connected with subjective perception of colours from the light of the lighting systems stepped by LED. Subjective observation of the colour change on the light of the lighting systems stepped by LED has been mostly related to extensive lighting systems where it was possible to observe identical light source (LED) within various angles. This phenomenon was manifested even more distinctively within lighting systems that made use of optical systems located in luminaries (reflector, diffusers) in a minimal way. Additional optical systems redistribute primary luminous flux coming from light source (LED) and thus there is a blending of luminous flux radiated to a certain angle of the illuminated space from various directions of the luminous flux radiation itself. In case it is not like this and the luminaries are equipped only with LED with a suitable luminous distribution curve, there is no blending of the luminous flux. Thanks to this the observer can also perceive various colours of light within individual luminaries perceived under various angles.