Simultaneous detection of the Ca and Ca layers by a dual-wavelength tunable lidar system.

A dual-wavelength tunable lidar system that simultaneously detects the Ca and layers has been established in Yanqing Station (40.41°N, 116.01°E).

Temperature-insensitive laser frequency stabilization to molecular absorption edge using an acousto-optic modulator.

A temperature-insensitive edge laser frequency stabilization method with an acousto-optic modulator (AOM) was proposed and demonstrated both theoretically and experimentally in this Letter. In the method, in addition to the unshifted laser frequency, two other shifted frequencies were generated by the AOM. The intensity ratio of these two shifted frequencies was used to stabilize the laser.

A flat spectral Faraday filter for sodium lidar.

We report a flat spectral Faraday anomalous dispersion optical filter (FS-FADOF) for sodium lidar. The physical and technical considerations for obtaining a FS-FADOF with a 3.5 GHz flat spectral transmission function are presented.

[Study on the electron density distribution of laser-induced air plasmas].

An 1. 06 microm Nd : YAG laser beam (energy: -500 mJ/pulse, pulse width: 10 ns, repetition rate: 30 Hz) was focused by a conical lens, and a column of laser-induced air plasmas (LIAP) came into being. The LIAP column, about 8 cm of long and 5 cm in maximal diameter, was studied by spectra measurement.

[Spectroscopic study on the time evolution behaviors of the laser-induced air plasma].

The time-resolved spectra of the air-breakdown plasma produced by the 1.06 microns beam of a Nd:YAG laser were investigated by using the time-delayed spectra and the spectral line evolution methods. The time evolutions of the short wavelength band and long wavelength band of the continuous spectra of the air-breakdown plasma have been measured.