Title :
Optical frequency domain ranging by a frequency-shifted feedback laser
Author :
Nakamura, Koichiro ; Hara, Takefumi ; Yoshida, Masato ; Miyahara, Toshiharu ; Ito, Hiromasa
Author_Institution :
Res. Inst. of Electr. Commun., Tohoku Univ., Sendai, Japan
fDate :
3/1/2000 12:00:00 AM
Abstract :
This paper describes the theoretical and experimental study of a new technique for optical frequency domain ranging (OFDR) by a frequency-shifted feedback (FSF) laser. In conventional OFDR, a frequency chirped single-mode laser is used as a light source to convert a distance into a beat frequency, and a tradeoff exists between measurement range and resolution. The FSF laser output consists of periodically generated chirped frequency components whose chirp rate is faster than 100 PHz/s (P=10/sup 15/), By use of the FSF laser, the tradeoff is removed and long-distance high-resolution OFDR is realized In the experiment, a distance of 18.5 km was measured with a resolution of 20 mm.
Keywords :
Fabry-Perot resonators; acousto-optical modulation; chirp modulation; laser feedback; neodymium; optical time-domain reflectometry; solid lasers; 18.5 km; YVO/sub 4/:Nd; beat frequency; frequency chirped single-mode laser; frequency-shifted feedback laser; light source; long-distance high-resolution OFDR; measurement range; optical frequency domain ranging; periodically generated chirped frequency components; Chirp; Frequency conversion; Frequency domain analysis; Frequency measurement; Laser feedback; Laser theory; Light sources; Optical feedback; Optical frequency conversion; State feedback;
Journal_Title :
Quantum Electronics, IEEE Journal of
