Profiling atmospheric water vapor using a fiber laser lidar system

Abstract

A compact, lightweight, and efficient fiber laser lidar system has been developed to measure water vapor profiles in the lower atmosphere of Earth or Mars. The line narrowed laser consist of a Tm:germanate fiber pumped by two 792 nm diode arrays. The fiber laser transmits approximately 0.5 mJ Q- switched pulses at 5 Hz and can be tuned to water vapor lines near 1.94 microm with linewidth of approximately 20 pm. A lightweight lidar receiver telescope was constructed of carbon epoxy fiber with a 30 cm Fresnel lens and an advanced HgCdTe APD detector. This system has made preliminary atmospheric measurements.

Isolator-free unidirectional thulium-doped fiber laser

“…The development of laser sources in this spectral band, based on radiative transitions in thulium and holmium trivalent cations, Tm 31 and Ho 31 , respectively, is motivated by numerous potential applications in spectroscopy, remote sensing, medicine, tele-communications, and material processing. For example, multiple absorption lines of atmospheric components, such as H 2 O, CO 2 , or NO 2 are exploited in differential absorption lidar (DIAL) systems [1][2][3][4] . The first vibration overtone of the O-H bond in water has an absorption wavelength of 1.92-1.94 mm, which can be used for laser surgery 5 .…”

Passively Mode-Locked 1.93-㎛ All-Fiberized Femtosecond MOPA Laser Using a Gold-Deposited Side-Polished Fiber

“…Thulium 첨가 광섬유 레이저의 경우 고체형 레이저 대비 광섬유 레이저가 갖고 있는 고유의 장점 인 높은 빔품질, 안정성, 유지보수편의성에 더하여 높은 펌 핑광 효율을 지니고 있어 현재 광섬유 레이저 분야에서 주요 한 연구 주제가 되고 있다. [1][2][3] 일반적으로 펄스 레이저를 구현하는 방법으로는 크게 Q-스위칭 과 모드 잠금 원리를 사용하는 두 가지의 방법이 존 재하며 이 방법들은 외부에서 동기화 구동 신호를 넣어 주느 냐 여부에 따라 능동형 [4][5][6][7][8][9] 과 수동형 [10][11][12][13][14] 으로 나뉜다. 그 중 펨토초 레벨의 극초단 펄스 레이저를 구현하기 위해서는 수 동형 모드잠금 방법을 사용하여야 하는 것으로 알려져 있다.…”

A highly efficient 57 pm Tm-doped fiber laser with two multimode fiber Bragg gratings

“…Tm-doped fiber lasers are promising in applications such as remote sensing [1,2], gas sensing [3,4,2], eye-safe lidar [5,6] and optical parametric oscillation (OPO) to generate mid-infrared lasers [7,8]. Most of these applications require narrow linewidth operation of the laser system [9,10].…”