Tubular light guide evaluation

Tubular light guides have found practical application in many buildings. They enable to improve illuminance level in internal parts of buildings. The paper presents results of investigation of straight tubular light guides. The theoretical description of light rays transport inside the tubular light guide and their distribution on the output from the light guide at the level of the ceiling is presented. The theoretical model is compared with light measurements. This study was completed for the evaluation of the function of the tubular light guide system and determination of design requirements.