Fast measurement of automotive headlamps based on high dynamic range imaging

Appl Opt. 2012 Oct 1;51(28):6870-80. doi: 10.1364/AO.51.006870.

Abstract

The headlamp of the automobile is a very important device for the safety of driving in the dark. Therefore, the distribution of the light designed to provide forward and lateral illumination needs to meet the requirements of various regulations. Traditional measurement of the distribution has been based on a point-by-point approach using a goniophotometer. In this paper, an imaging photometer is developed by combining a regular digital camera and a high dynamic range imaging technique to achieve faster and more complete measurement of the entire distribution. The experimental results indicate that errors of the measurements are within 10% of the true values, which is better than the 20% requirements of the industry.