Studies On The Filter For Photorejuvenation

Intense Pulsed Light photorejuvenation is the newest hairdressing technology after laser hairdressing technology. The principle of the technology is the intense pulsed Xe light emits wide spectral range, special filter are used to filtering UV-light and select standard wave range for treatment, the light have the effect on human's skin organization and have hairdressing impact. The difficulty of the related filter's design and deposition lie in the high requirement about high transmittance of pass band, broad rejection zone and high steepness. There are several aspects discussed in this article. Two methods are adapted to design filters in the article: stack formula design and automatic optimizing design. We use long-pass symmetrical period as main film system when using regular layers design method. Besides the Herpin index method, a new non-symmetrical period matching layers approach is also been put forward. Comparing the two methods, the latter is superior to the former in several aspects. So non-symmetrical period matching layers approach is proved to be a good film design method and can also be used to other symmetrical film design. The traditional local optimizing method, Needle method and Tunneling method are mixed used in automatic optimizing design. We consider thickness tolerance and thickness restriction as parameters in the design, structure new merit function; analyze the influence of initial film thickness and the initial film material to optimizing results, find the most suitable initial parameters. Comparing the thickness sensitivity of different filter, the best theoretical result can be got. So it has actual instructional meaning when actually depositing multi-layer coating. Deposing factors include substrate temperature, evaporation rate, beam density and screen pole voltage are analyzed by using the orthogonal intersection experiment method, finding their influences for quality of coating surface, adhesion and spectrum characteristics. So the best IAD technology factors are gotten. Also analyze the influence for the filter's performance of the air anneal after the film deposition. Many experiments are done to acquire the best anneal temperature and time. So we accumulate some guiding significance results for the future study. The filters that deposited by IAD technology and usual E-Beam method are tested on optical, physical and chemistry characters. It indicated that using IAD technology can increase packing density, improve the filter's structure and optical character. At last, this article completed lots of experiments on optical coating deposition. The filter for photorejuvenation are deposited, which had been used in photorejuvenation machine and well satisfy practical usage.