Illuminance Uniformity Filter for Theatrical Lighting Fixture

Abstract

The UNL Glare Apparatus was designed to systematically vary the four primary factors which affect discomfort glare, including source luminance, source size, source position, and background luminance. It was also designed to have considerable flexibility to research many additional independent and dependent variables. The theatrical lighting fixtures used in the apparatus caused a significant problem for scientific research: the output from the fixture did not produce a uniform illuminance on the target. A “uniformity” filter was created to produce uniform illuminance on the stimulus. This paper describes the nonuniform illuminance problem and the creation of a “uniformity” filter to correct the problem. The complete Matlab code used to generate the filter is available from the authors.

Keywords:

• filter
• uniformity
• theater lighting fixture
• gobo