The Light-tube Method for Lighting Calculations in a Near Field

摘要

The new method for computing the illuminance in a near field of an axially symmetrical luminaire is presented. It is referred to as a light tube method. The method uses basic concepts of the light field theory: a light vector, a light line, and a light tube. The main advantage of the method is that input data are defined in a traditional way, like measuring luminous intensity of a luminaire. The difference is that the measurements are carried out for several distances in a near field. If the results of the measurements at the selected distance in a far field are added, one may obtain a unified table of luminous intensities both for near and far fields. The data can be presented in standard electronic formats and used in lighting computer programs.