DIODE-PUMPED LASER ALTIMETER

DIODE-PUMPED SOLID STATE LASERS ARE COMPACT, RELATIVELY EFFICIENT, LONG-LIFETIME SOURCES OF COHERENT RADIATION AND ARE WILL-SUITED TO A NUMBER OF NASA SPACE-BASED, ACTIVE REMOTE-SENSING SYSTEMS. WE PROPOSE TO COMBINE THE USE OF A DIODE-ARRAY-PUMPED NEODYMIUM (ND) LASER WITH PULSE-TRANSMISSION-MODE (PTM) Q-SWITCHING TO GENERATE THE ONE-NANOSECOND-DURATION PULSES REQUIRED FOR ONE PARTICULAR SENSING APPLICATION, HIGH-PRECISION LASER ALTIMETRY. THIS COMBINATION HAS, TO OUR KNOWLEDGE, NOT YET BEEN IMPLIMENTED IN DIODE-PUMPED LASERS, BUT IS MORE FAVORABLE FOR NANOSECONDPULSE GENERATION THAN MORE CONVENTIONAL Q-SWITCHING TECHNIQUES. IN ADDITION, WE PROPOSE TO IMPROVE THE OVERALL EFFICIENCY OF TRANSVERSE-PUMPED, SINGLE-TRANSVERSE-MODE ND LASERS OVER CURRENT LEVELS BY THE USE OF INNOVATIVE PUMPING AND LASER-CAVITY GEOMETRIES. THE IMPROVEMENT IN EFFICIENCY AND SUBSEQUENT REDUCTION IN BOTH ELECTRICAL POWER CONSUMPTION AND HEAT GENERATION ARE OF MAJOR IMPORTANCE IN SPACE-BASED SYSTEMS, AND HAVE SIGNIFICANCE FOR A WIDE RANGE OF REMOTE-SENSING APPLICATIONS.