Light absorption measurement apparatus and method

摘要

Apparatus and methods are disclosed for measuring changes in light absorption of a sample optical component. The sample is held in a sample holder in a sample chamber during irradiation by an intense light, usually pulsatile light. Molecules of a gas are introduced into the sample chamber as the sample is irradiated. The molecules can be of a material suspected to become adhered to or absorbed by the sample in a way that causes an undesired change in light absorption by the sample. Changes in light absorption by the sample are preferably measured photoacoustically. The molecules of the gas can be generated by controlled irradiation of a "source material" with a light (which can be the same as used to irradiate the sample) sufficient to generate such molecules of gas from the source material, and routing the gaseous molecules to the sample as the sample is irradiated. <IMAGE>