Band Ⅰ DIRCM laser based on GaSb direct diode technology

摘要

The proliferation of man-portable air-defense systems (MANPADS) is extremely wide. MANPADS are responsible for over 60% of total aircraft casualties since 1960's. It is estimated that over 500,000 of these systems are deployed worldwide with a large number being out of governmental control. Directional infrared countermeasure (DIRCM) systems have been deployed in order to counter the threat. Laser based DIRCM system requires laser sources which can operate in bands Ⅰ,Ⅱ and Ⅳ. Up to day bands Ⅱ and Ⅳ are covered by compact and lightweight quantum cascade lasers (QCLs), but for wavelength generation in band I, bulky and expensive solid-state or fiber laser solutions are used. Recent development of GaSb laser diode technology at Brolis Semiconductors greatly improved optical output powers and efficiency of laser diodes working in 1900 - 2450 nm range (band Ⅰ). In this work we present a laser diode module which is based on incoherent beam combining of two high-power GaSb laser diode emitters working in 2.1-2.3 urn spectral band. This laser module is capable of providing directional beam with radiant intensity value of more than 30 kW/str. Module is extremely compact and lightweight (<50 g). E-O efficiency of the module is 15% and it can be operated in CW or pulsed operation modes replicating any waveform required for DIRCM application.