Considerations for reflective laser eye protection against ultrafast lasers

The inherently broad spectral bandwidth of ultrafast (mode locked) lasers can potentially exceed the protection bandwidth of laser eye protection. This is a particular concern for reflective laser eye protection technologies which by design possess sharp often narrow spectral protection notches. The purpose of this paper is to report spectral transmittance of an ultrafast laser through an interference filter typifying those currently used in laser eye protection and to examine the impact of spectral and angular leakage on the level of protection provided.