TY - JOUR
T1 - Measurement of low loss and mirrors' reflectivity using cavity ring down spectroscopy with high accuracy
AU - Yang, Dexing
AU - Jiang, Yajun
AU - Zhao, Jianlin
AU - Di, Nan
PY - 2006
Y1 - 2006
N2 - Differential laser gyro is an ideal equipment to solve the "lock-in" behavior. The ring cavity must be low loss and the reflectivity of mirrors in gyro must be more than 99.99%. But the insertion of a piece of quartz glass and a Faraday cell in the cavity will broaden the "lock-in" area due to additional loss, so it is very important to measure ultra-high reflectivity of mirrors and the loss of transparent glass plate used in gyro. 632.8nm He-Ne laser is the most suitable light to travel around the ring cavity in gyro, so the traditional cavity ring down spectroscopy (CRDS) must be improved by using continuous-wave (CW) He-Ne laser instead of pulsed one. The results show that the single-pass loss through the glass plate can be kept below 3.0×10 -11cm -1. Using combination of linear and folded cavity ring down spectroscopy, the loss such as absorption of gas in the cavity are counteracted due to the equalized length of cavity, so the reflectivity of the mirrors is measured with high accuracy. The ring down time of the cavity with and without a sample is obtained respectively, and then the total loss of the measured sample is calculated. The results show that the improved CRDS is suitable for accurately measuring low loss of medium and reflectivity of mirrors.
AB - Differential laser gyro is an ideal equipment to solve the "lock-in" behavior. The ring cavity must be low loss and the reflectivity of mirrors in gyro must be more than 99.99%. But the insertion of a piece of quartz glass and a Faraday cell in the cavity will broaden the "lock-in" area due to additional loss, so it is very important to measure ultra-high reflectivity of mirrors and the loss of transparent glass plate used in gyro. 632.8nm He-Ne laser is the most suitable light to travel around the ring cavity in gyro, so the traditional cavity ring down spectroscopy (CRDS) must be improved by using continuous-wave (CW) He-Ne laser instead of pulsed one. The results show that the single-pass loss through the glass plate can be kept below 3.0×10 -11cm -1. Using combination of linear and folded cavity ring down spectroscopy, the loss such as absorption of gas in the cavity are counteracted due to the equalized length of cavity, so the reflectivity of the mirrors is measured with high accuracy. The ring down time of the cavity with and without a sample is obtained respectively, and then the total loss of the measured sample is calculated. The results show that the improved CRDS is suitable for accurately measuring low loss of medium and reflectivity of mirrors.
KW - Cavity ring down spectroscopy
KW - Differential laser gyro
KW - Low loss
KW - Reflectivity
UR - http://www.scopus.com/inward/record.url?scp=33645321128&partnerID=8YFLogxK
U2 - 10.1117/12.677964
DO - 10.1117/12.677964
M3 - 会议文章
AN - SCOPUS:33645321128
SN - 0277-786X
VL - 6150 I
JO - Proceedings of SPIE - The International Society for Optical Engineering
JF - Proceedings of SPIE - The International Society for Optical Engineering
M1 - 615007
T2 - 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment
Y2 - 2 November 2005 through 5 November 2005
ER -