Diode laser lidar wind velocity sensor using a liquid-crystal retarder for non-mechanical beam-steering
- Authors:
- DOI:
- 10.1364/OE.22.026674
- Abstract:
- We extend the functionality of a low-cost CW diode lasercoherent lidar from radial wind speed (scalar) sensing to wind velocity(vector) measurements. Both speed and horizontal direction of the wind at~80 m remote distance are derived from two successive radial speedestimates by alternately steering the lidar probe beam in two different lines-of-sight (LOS) with a 60° angular separation. Dual-LOS beam-steering isimplemented optically with no moving parts by means of a controllableliquid-crystal retarder (LCR). The LCR switches the polarization betweentwo orthogonal linear states of the lidar beam so it either transmits throughor reflects off a polarization splitter. The room-temperature switching timebetween the two LOS is measured to be in the order of 100μs in one switchdirection but 16 ms in the opposite transition. Radial wind speedmeasurement (at 33 Hz rate) while the lidar beam is repeatedly steered fromone LOS to the other every half a second is experimentally demonstrated –resulting in 1 Hz rate estimates of wind velocity magnitude and direction atbetter than 0.1 m/s and 1° resolution, respectively
- Type:
- Journal article
- Language:
- English
- Published in:
- Optics Express, 2014, Vol 22, Issue 22, p. 26674-26679
- Main Research Area:
- Science/technology
- Publication Status:
- Published
- Review type:
- Peer Review
- Submission year:
- 2014
- Scientific Level:
- Scientific
- ID:
- 272773246