公开(公告)号：WO2021023971A1

公开(公告)日：2021-02-11

申请号：PCT/GB2020/051816

申请日：2020-07-29

Applicant: QLM TECHNOLOGY LTD

Inventor： AI, Xiao ,  TITCHENER, James

IPC: G01S7/48 ,  G01S7/481 ,  G01S7/4911 ,  G01S7/493 ,  G01S17/04 ,  G01S17/32 ,  G01S17/88 ,  G01S17/95

Abstract: A method of operating an optical device, the method comprising tuning a first emission wavelength of a first output radiation of a laser device continuously within a first wavelength spectrum by modulating a drive current thereof with a first drive current modulation having a frequency of at least 100 kHz. The first wavelength spectrum comprises a first spectral feature associated with at least part of a gas absorption spectrum of at least one gas. The method comprises the steps of modulating the first output radiation of the laser device with a first output modulation, the first output modulation comprising a first plurality of binary pulses, scanning the first wavelength spectrum at a rate of at least 1 µm per second, projecting the first output radiation towards a first target area, receiving scattered radiation from the first target area, and processing the scattered radiation.