Project Title:

Stabilized Diode Laser for Laser Metrology

92-1-08.20-7786A                                                  NAS05-32419
Stabilized Diode Laser for Laser Metrology
Environmental Optical Sensors, Inc.
3704 North 26th Street
Boulder, CO  80302
S. Eric Wheatly                                      (303-440-7786)

Abstract:

     NASA requires compact, rugged optical sources which have a
stable reproducible center frequency and a long coherence length
(narrow linewidth) for laser metrology applications. This project
will use a Doppler-free, two-photon absorption (DF2PA) transition
in an alkali vapor as an absolute frequency reference that in turn
is used with negative electrical feedback to stabilize a diode
laser and narrow its linewidth. This approach offers a wider
choice of wavelengths (including visible) than an approach using a
saturated resonance line. The objectives in Phase I are to
demonstrate stabilization and line narrowing using DF2PA, to
identify and minimize the factors which affect the absolute
stability of the laser, and to build a compact prototype packaged
laser using this approach. The Phase I effort includes modeling
specific 2PA transitions, constructing and evaluating various
reference cells, and constructing a prototype packaged laser. The
result of Phase I will be operational prototype laser hardware and
an understanding of how to design flight-qualified hardware to
NASA specifications. The availability of a space-qualified
stabilized diode laser will be useful to NASA for laser metrology,
especially absolute distance measurements in space to assist in
assembly of structures. Other applications include improved
optical sensors, remote sensing, and communication.

Potential Commercial Application:

Potential Commercial Applications:  Potential commercial
applications for stabilized lasers are precision metrology (such
as distance measurement), fiber optic sensors (such as laser
gyroscopes), and wideband optical communications systems.

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