Absorption and Fluorescence Measurements in Optical Coatings

Abstract

Absorption characterization of optical thin films and coatings has become one central task for the manufacturers e.g. to ensure stability in the production process, to verify functionalities and to understand possible performance changes and limitations during their use in e.g. high power laser applications. Set by this trend, numerous direct absorption measurement techniques have been developed in the last two decades which all—despite particular pro and cons—feature a high sensitivity. However, the different techniques possess remarkable differences regarding a universal and efficient absolute calibration procedure. After a survey of different measurement techniques with their calibration procedures, this chapter will focus on the laser induced deflection (LID) technique, its independent absolute calibration, particular measurement concepts and experimental results.