Acta Photonica Sinica, Volume. 45, Issue 6, 631001(2016)
Monitoring Method for Filter Film Thickness Based on the Combination of Photoelectric Extreme Value and Quartz Crystal Oscillation
According to the disadvantages of both photoelectric extreme value and quartz crystal oscillation methods, a combination method based on photoelectric and quartz control were presented. To evaluate the performance of the combination method, the films with coating thickness of 905 nm narrow band filter (quarter wave coatings) and 830nm cutoff filter (non-quarter wave coatings) were monitored using the combination method and individual method respectively under the same process. The combination method shows better performance, compared to the case of using an indiviual method. From the spectral transmittance curves of filters, the average transmittance values in the pass bands increase by 3%~6% by using the combination method. Meanwhile, the transmittance curve achieved by the combination method consists well with the theoretical spectral curve. The results show that this method can not only monitors quarter wave coatings and non-quarter wave coatings, but also effectively reduce the monitoring error and improve the spectral characteristics.
Get Citation
Copy Citation Text
ZHANG Xue-dian, QIAN Yan-hua, CHANG Min, JIANG Min-shan. Monitoring Method for Filter Film Thickness Based on the Combination of Photoelectric Extreme Value and Quartz Crystal Oscillation[J]. Acta Photonica Sinica, 2016, 45(6): 631001
Received: Dec. 8, 2015
Accepted: --
Published Online: Jul. 26, 2016
The Author Email: Xue-dian ZHANG (zhangxuedian@hotmail.com)