3.3–3.7 μm Nested cavity OPO pumped by an amplified micro-laser for portable DIAL

Nested Cavity optical parametric oscillators (NesCOPOs) have been proven to be performing tools to achieve the single frequency operation and fine frequency control needed for gas sensing applications. This paper presents a new transmitter, designed to demonstrate improved integrated path differential absorption LIDAR (IPDIAL) performances. Such a new transmitter is designed to respond to the need for detection of other species (especially CH
₄
), with an extended range of operation (> 100m). It is based on a 1.064μm pump source, which is a fiber amplified microlaser achieving single frequency, 8 ns pulse duration and a 200μJ per pulse energy level at a repetition rate of 2 kHz with an excellent beam quality (M
²
<;1,08). The laser is based on a co-propagative MOFA architecture. The seed master oscillator is a microlaser specially tailored by Teem photonics to produce a single frequency 1.064μm signal at 15μJ, 8ns per pulse at 2kHz. Such microlaser have already been successfully used to pump directly NesCOPOs in the past. The high gain amplifier is a Taranis, Nd doped - YAG fiber module from Fibercryst. Such a fiber amplifier had been already tested successfully to amplify sub nanosecond passively Q-switched microlasers [4]. The type 0 PPLN NesCOPO device allows 3.3 - 3.7 μm coverage.