Development of standard spectral filter in photorejuvenation

A filter for producing the standard spectrum band in photorejuvvenation device was developed. Quartz was selected as the substrate, TiO2 and SiO2 were chosen as high and low refractive index film materials. The needle optimizing method was used to eliminate the ripple. By using vacuum depositing method with ion-assisted deposition system, the filter with average transmittance less than 0.3% in 200 nm~550 nm and over 95% in 570 nm~1200 nm was achieved. In the process of evaporating, an improved monitoring method was used to reduce the absorption of TiO2 and the film thickness error. Based on repeated experiments, the reason of wavelength shift was analyzed and the feasible method for solving the problem was put forward.