FIBERTEK, INC. — National Aeronautics and Space Administration SBIR Phase I: S1

Description

<p>Fibertek, Inc. will develop a single-frequency, Er:YAG laser transmitter to advance the technological readiness level (TRL) of a key technology component of the 3D wind measurements identified in the recent Earth science decadal survey &ldquo;Thriving on Our Changing Planet: A Decadal Strategy for Earth Observation from Space&rdquo;<strong>.&nbsp; </strong>The Er:YAG development will advance the technology of a space-based wind lidar system by focusing on developing a compact, efficient diode pumped transmitter that is conductively cooled.&nbsp; Current efficient 2&micro;m systems are pumped by fiber lasers to take advantage of the high brightness source, but this tends to increase the packaging foot print.&nbsp; To maintain long pulsewidths &gt;100ns, the 2&micro;m systems cavities are typically greater than 2 meters in length. &nbsp;By working at higher repetition rates (500Hz or above) than are typically targeted in 2&micro;m systems, Fibertek will take advantage of the long storage time of Er:YAG to maintain efficient operation, while operating at longer pulse lengths in a shorter cavity (with respect to Ho:YLF systems of similar pulse lengths) due to the low gain of the Er:YAG.&nbsp; Fibertek&rsquo;s approach will be based on an Er:YAG resonator operating at 1645nm and resonantly pumped by high brightness semiconductor laser diodes.</p><p style="margin-left:0in; margin-right:0in">This program will build on successful Er:YAG work at Fibertek focused on methane and water vapor lidars.&nbsp; These systems are 7-10W systems optimized for operation at higher repetition rates.&nbsp; The Phase I work will demonstrate a high power (&gt;12.5W) oscillator optimized for 500Hz operation with a Technology Readiness Level 4 (TRL-4) for a coherent wind lidar. In Phase II we will develop a hardened brassboard version of the laser that would be suitable for airborne systems. We will also perform a trade study on how to achieve the highest damage threshold coatings at 1.6455 &micro;m.</p>