Search NASA⌕ Search

SEARCH · Search NASA

Results for “CARBON DIOXIDE LASERS”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4

True airspeed measured by airborne laser Doppler velocimeter

Velocimeter utilizing carbon dioxide laser measures true airspeed of aircraft. Results of flight tests indicate that clear-weather airspeeds can be measured with accuracy better than 0.1% at altitudes up to 3000 meters; measurements can be made at much greater altitudes in cloudy or turbid air.

Munoz, R.↗

Optogalvanic stabilization and offset tuning of a carbon dioxide waveguide laser

A feedback loop employing the change in discharge impedance with output power is used to stabilize the frequency of a CO2 waveguide laser. The relatively high operating pressure of the laser combined with a zero offset feature in the feedback loop allows continuous tuning of the stabilized frequency over a 300-400 MHz range.

Kavaya, M. J.↗

Spectrophone stabilization and offset tuning of a carbon dioxide waveguide laser

A sensitive spectrophone containing CO2 gas is incorporated into a feedback loop to stabilize the frequency of a CO2 waveguide laser. First or second harmonic detection combined with a zero offset feature and the relatively high operating pressure of the laser allows continuous tuning of the stabilized frequency over a 400 MHz range. Frequency stability of better than + or - 1 MHz is achieved.

Kavaya, M. J.↗

One-megawatt solar pumped and electrically driven lasers for space power transmission

High power lasers in space could provide power for a variety of future space missions such as spacecraft electric power requirements and laser propulsion. This study investigates four electrically pumped laser systems, krypton fluoride, copper vapor, laser diode array, and the carbon dioxide laser, all scaled to 1-MW laser output. Each system obtained its primary power from a large solar photovoltaic array which, in turn, provides power for the appropriate laser power conditioning subsystem. Each system was block-diagrammed, and the power and efficiency were found for each subsystem. The laser diode array had the highest solar-to-laser efficiency (6 percent) and smallest radiator area making it the most advantageous of the electrically driven lasers studied. This system was then compared with an iodine solar pumped laser system previously studied. The diode array had a better wavelength with regard to transmission optics mass, but it also had a heavier radiator because of its lower temperature radiator requirement. A more advanced solar pumped laser could emerge as the preferred laser system for space applications.

Deyoung, R. J.↗

Multichannel television coupling modulation experiments using a CO2 laser.

Experiments are described in which a carbon dioxide laser oscillating at 28.4 THz has been modulated simultaneously by three commercial television signals with carriers at 54, 66, and 82 MHz. Signal-to-noise degradation in the system was measured to be less than 1 dB, corresponding to modulator drive power of 1 W. This combination of wide bandwidth and low power consumption was made possible by the application of coupling modulation. This technique employs an intracavity electrooptic crystal to which the modulating fields are applied. Despite the fact that the crystal is positioned inside the laser cavity, the maximum bandwidth attainable is independent of both the cavity Q and the laser transition linewidth, and is limited only by modulator characteristics and optical transit time. Rigrod's (1965) method has been adapted to obtain an expression for the power coupled out of the laser. Modulator frequency response and drive power requirements are also summarized. It is seen that the noise bandwidth performance of the system would allow simultaneous modulation by 17 color television channels, or equivalently, more than a 300-megabit/sec capacity.

Hall, D. R.↗

Laser furnace technology for zone refining

A carbon dioxide laser experiment facility is constructed to investigate the problems in using a laser beam to zone refine semiconductor and metal crystals. The hardware includes a computer to control scan mirrors and stepper motors to provide a variety of melt zone patterns. The equipment and its operating procedures are described.

Griner, D. B.↗