Stroboscopic Surface Thermal Lensing for Fast Detection of Thermal Defects in Large-Scaled Coating Films

Abstract EN

A stroboscopic surface thermal lensing (SSTL) system for the fast detection of thermal-induced defects in large-scaled optical coating films was constructed.

The SSTL signal was generated by a set of double-modulators and captured by a high speed matrix camera, respectively.

The spot size of both pump laser and probe laser expanded for larger detection area was finished in a single step.

Based on the STL technique, both the mapping of amplitude and the phase of SSTL signal on the whole area of the coatings can be achieved simultaneously.