Accuracy of Lighting Simulation Programes(<Special Issue>Prospect of Lighting Simulation Program)

Abstract

Test cases to assess the accuracy of lighting simulation programes were proposed in the CIE 171:2006. Five fundamental cases were extracted and summarized in this article, and the accuracy of four programes - Dialux, Lumicept, Radiance, 3ds Max - was verified with these cases. Test case 1 & 2 are to inspect the accuracy based on the measurement data. For point illuminance measurements, the reference values are presented by means of two pairs of upper and lower limits, where the first pair defines a band of values including the measurement errors and the second pair defines a band including both measurement and simulation errors. Test case 3 & 4 & 5 are to compare simulation values with analytically calculated data. Test case 3 check the accuracy of direct illuminance by artificial point light sources, test case 4 check the accuracy of direct illuminance by artificial area light sources, and test case 5 check the inter-reflections. As to test case 1 & 2 & 3, all programes get satisfactory results for the most part.