Title of Paper: Robust, Single-Frequency Ring Oscillator
Principal Author: Dr. Floyd Hovis
Abstract: The Earth Science Enterprise Capability Matrix
identifies space-based ozone differential absorption lidar (DIAL) as a high
priority instrument in need of technology development. A critical component of
the ozone DIAL system is a space-qualified 1µm pump source that provides single
frequency, high energy, and high beam quality pulses in a dual-pulse format.
These pump requirements maximize conversion efficiency and minimize the risk of
damage for the nonlinear processes used in the UV laser. Although 1µm
laboratory lasers can achieve the desired output, the technologies on which
these lasers are based are not compatible with the requirement to operate in
space. Common shortcomings include the inability to survive the vibrational
environment of a launch, sensitivity to thermal variations, and liquid-based
cooling for heat removal. The overall objective of our ESTO funded research is
the demonstration of 1 µm laser technology that is space-qualifiable and
capable of achieving the following characteristics:
Our presentation will focus on the first phase of our ATIP sponsored work
in which we built and characterized an innovative unstable ring oscillator that
achieves both single-frequency operation and mechanical robustness. The ring
design is an extension of unstable linear cavity designs developed and
delivered in other Fibertek laser systems. It incorporates a diode-pumped,
conductively cooled, zig-zag slab head. We will describe the design details
that allowed us to achieve the following performance from the ring oscillator.
< 5% energy loss for 500 µrad misalignment