Paper Title
Engineering Conception, Design Simulations and Demonstration Facets of a Compact Eye-Safe IR Laser for Short Range and Spectroscopy Applications

Abstract
Recent decade has attested a substantial advancement in development and application of eye-safe lasers in various scientific and engineering areas i.e., range finding, sample composition analyses, impurity monitoring etc. Suitability prospects and potential use of such lasers are even explored for various space missions. This paper is primarily focused towards the in-house realization of a compact (overall length of 55 mm), light weighted and low power consuming passively q-switched and transversely diode pumped Yb-Er-Phosphate glass IR laser source capable of producing 0.3-0.5 MW peak power and suitable for short range (10 km) and in-situ (~ 200 mm up from sample surface) distance sample composition applications. Tradeoff cavity design simulations as a function of doping density, reflectivity, intra separation elements and pump duration were carried out. Analysis of design simulations revealed a laser resonator capable of emitting narrow-width pulses of duration of 3 ns-7 ns, pulse energy in range of 5 mJ-10 mJ at 1.54 m wavelength with a beam divergence of 4 mrad and diameter of ~ 0.4 mm. Resulted temperature distribution profile shown maximum temperature of 300 0K on the laser rod, thus supporting air-cooling. The reported work in this paper casts light on details of engineering conception strategy, performed trade-off design simulations employing LASCAD and bench-top test setup realisation prospects. Keywords - Diode pumping, rare-earth ion doped glasses, passive q-switching, ranging and remote sensing