Study on design and deposition of minus filters for laser protection application

Minus filters are by definition filters that eliminate one wavelength band from a spectrum and transmits at both shorter and longer wavelengths. Such filters would be useful in such optical systems for rejecting a laser threat while transmitting others. Paper focused on use the equivalent-layer concept to design minus filters. According to design 532nm minus filter and 1064nm minus filter were deposited by ion beam assisted deposition method. Results show that the filter was provided with good performance and environmental stability. The results of damage threshold of coating for 10ns pulse: 859MW/cm2.