Development of the marine Raman lidar system

摘要

The progress toward developing a technique for the underwater remote detection of gases using Raman lidar is reported. In this work, we describe the development of the marine Raman lidar system for monitoring the CH_4 gas of Taketomi submarine hot spring. The transmitter of lidar system was the third harmonic of a standard Q-switched Nd:YAG laser (355 nm). The receiver of this system consisted by a telescope with a diameter of 200 mm, a spectrometer, a CCD camera for measuring Raman spectrum, and a PMT for monitoring Raman lidar signals. In order to evaluate the performance of our system, we demonstrated the Raman spectroscopic measurements from a barge down to the water depth of about 30 m.