Laser Doppler velocimetry by modulating a CO2 laser with backscattered light.

A portion of the Doppler shifted light backscattered from a moving diffuse target is allowed to reenter the CO2 source laser. The laser power, monitored by a photodiode through a partially transmitting mirror on the rear of the laser, is modulated at the Doppler frequency. Two regimes of operation are observed. For the laser operating well above threshold, the Doppler signal level is relatively insensitive to the laser operating point. A narrow region of enhanced sensitivity is observed, however, for laser operation at a point near threshold.

[1]  A. Mooradian,et al.  Spectral characteristics of external-cavity controlled semiconductor lasers , 1980 .

[2]  James H. Churnside,et al.  Speckle from a rotating diffuse object , 1982 .

[3]  J. Goodman.  Statistical Properties of Laser Speckle Patterns , 1963 .

[4]  W. R. C. Rowley,et al.  Optical coupling effects in frequency stabilized lasers. , 1972, Applied optics.

[5]  R. Salathé,et al.  Diode lasers coupled to external resonators , 1979 .

[6]  R. O. Miles,et al.  Phase sensitivity and linewidth narrowing in a Fox–Smith configured semiconductor laser , 1982 .

[7]  N. L. Abshire,et al.  Doppler Lidar Observations of Hydrometeors. , 1974 .

[8]  I. Potter.  Frequency Response of the 6328‐Å Helium‐Neon Laser Interferometer , 1969 .

[9]  J. Verdeyen,et al.  PLASMA REFRACTIVE INDEX BY A LASER PHASE MEASUREMENT , 1963 .

[10]  N. Brown.  Frequency stabilized lasers: optical feedback effects. , 1981, Applied optics.

[11]  F. Favre,et al.  Optical feedback effects upon laser diode oscillation field spectrum , 1982 .

[12]  G. Bekefi,et al.  Laser Interferometer for Repetitively Pulsed Plasmas , 1966 .

[13]  A. Malein,et al.  Performance of the He–Ne Gas Laser as an Interferometer for Measuring Plasma Density , 1965 .

[14]  J. Verdeyen,et al.  High‐Frequency Laser Interferometry in Plasma Diagnostics , 1965 .

[15]  D. Ashby,et al.  MEASUREMENT OF PLASMA DENSITY USING A GAS LASER AS AN INFRARED INTERFEROMETER , 1963 .

[16]  David J. Wilson,et al.  A Laser Velocimeter for Remote Wind Sensing , 1972 .

[17]  W. Bludau,et al.  Characterization of laser-to-fiber coupling techniques by their optical feedback. , 1982, Applied optics.

[18]  R. O. Miles,et al.  Spectral characteristics of semiconductor lasers with optical feedback , 1982 .

[19]  A. Olsson,et al.  Coherent optical interference effects in external-cavity semiconductor lasers , 1981 .

[20]  S J Fielding,et al.  Interferometry using a laser as radiation source, amplifier and detector , 1972 .

[21]  T R Lawrence,et al.  Calibration of coherent lidar targets. , 1980, Applied optics.

[22]  W J Burke,et al.  Optical feedback effects in cw injection lasers. , 1978, Applied optics.

[23]  Alan B. Tveten,et al.  Feedback‐induced line broadening in cw channel‐substrate planar laser diodes , 1980 .

[24]  Emil Wolf,et al.  Principles of Optics: Contents , 1999 .