SBIR-STTR Award

Operation of hydrogen fluoride(hf) chemical lasers on overtone transitions (ots) has the promise of leading to efficient, high power laser devices at short wavelengths. An ot laser experimental study in a photolytically initiated pulsed laser is being undertaken. This approach is anticipated to remove two continuous wave (cw) ot experi mental limitations: short single-device gain length and medium non uniformity. Thus the approach is expected to allow the unambiguous study of issues associated with ot lasers with their low zero power gain. This would include accurate experimental comparisons of the performance characteristics (low power through highly saturated) of a pulsed hf chain reaction chemical laser when operating only on fundamental transitions (delta v=1) and only on first overtone transitions (delta v=2), and experimentally determine resonator length limitations on ot pulsed laser operation caused by super radiant losing of the fundamental transition mechanism. In the cur rent effort, the detailed development of the test capabilities is being undertaken, including identification of test series groups and design of the laser test facility, and diagnostic systems, x instruments, and techniques.

A pulsed hydrogen fluoride overtone chemical laser operating on the change reaction between hydrogen and fluorine has been devised, and parameters established for operation on fundamental tone (FT), and first and second overtone transitions (OT). The wavelength variable coatings used to promote OT and suppress FT are also being tested for performance in a pulsed laser. The pulsed laser delivers more energy and more lasing transitions with favorable gain values than does a continuous wave laser. When fully optimized, the pulsed HF overtone transition laser will efficiently provide increased brightness for high energy laser systems. Applications include laboratory research lasers, laser energy weapons, and laser communication systems.