Estimation of the light source position on the basis of the light point figure

Abstract

The light point figure is an image of a source of light seen in the reflector surface of a headlight. The source location is one of decisive parameters that influence the shape of the figure. The paper is an attempt to estimate the source of light location on the basis of the shape of the light point figure. The location in the reflector focus was assumed as a standard position. The displacement along an optical axis and perpendicular axis was considered. A set of factors that describe the shape of the figure was introduced. Through using them the functional dependencies between source's displacement and shape of figure were defined. An algorithm for determining the source location (displacement in relation to standard position) was introduced. This algorithm uses proposed functional dependencies and nonlinear programming methods. The light point figure is calculated using ray tracing.