(U) The overall goal of this thrust is to establish the feasibility and payoff of lasers in advanced weapon, communication, illumination, and optical counter-measure applications. Development efforts continue to address the concerns of scaling to high power, good beam quality, and high efficiency, but have recently included increased emphasis on suitability for specific classes of applications and operational environments. This has placed additional emphasis on operation in specific wavelengths bands, packaging for minimum weight and volume, and reliability and affordability in real weapon system applications. an optically-pumped 4 micron diode laser was demonstrated and is being transitioned to the numerous users for self protection applications.
(U) Continued research into developing high power semiconductor lasers and arrays has resulted in significant achievements during the past year. Over 160 watts of quasi-coherent, continuous-wave power from an array of 64 elements was demonstrated. This device is an extremely bright source that will be useful in a number of near term applications. Research in the scaling of single devices resulted in approximately 5 watts, continuous-wave, diffraction-limited power from a single broad area laser. These achievements establish a foundation for further scaling of semiconductor laser diodes to meet application requirements involving high power, including directed energy weapons.
(U) Great strides were also made in the investigation of semiconductor laser diodes at mid-IR wavelengths during the past year. Over 2 watts peak (380 milliwatts average) power from an optically-pumped 4 micron diode laser was demonstrated and is being transitioned to the numerous users for self protection applications. This accomplishment is an important step in producing laser sources for use in self-protection and stand-off detection applications. Investigation of nonlinear optical methods for laser wavelength agility continues to show improvement in efficiency and optical quality. A sodium wavelength source using multiple optical parametric processes that has ideal pulse format and optical quality characteristics has been demonstrated. Nonlinear optical system design models have been developed that enable the scaling of these frequency agile laser sources to at least the tens of watts level. In collaboration with the Wright Laboratories, new and exotic nonlinear optical materials are being evaluated for use in efficient moderate to high power laser sources.
(U) The high-power semiconductor laser program has successfully demonstrated output powers in the mid-IR wavelength region sufficiently high enough for aircraft self-protection. For this reason, the program has been expanded to include packaging several 4 micron. optically-pumped semiconductor lasers for delivery to the Army, Navy, and Air Force for effects testing. The inherent compactness and ruggedness of semiconductor lasers may enable them to become the lasers of choice for self-protection systems. Also, a 2.1 micron diode laser was incorporated into a prototype ground-vehicle system and field tested by the Army. In the area of laser wavelength agility using multiple nonlinear optical processes, emphasis has shifted from producing visible wavelength sources to near ultraviolet and the mid-to-far infrared. In addition, the recently developed exotic nonlinear optical materials that are produced using a periodically poled technique are being studied for possible application in extremely efficient, frequency agile, high power laser systems.
|Laser Technology||Laser Technology|
|TECHNOLOGY- RDT&E||SPACE TECHNOLOGY|
(U) National Security Space Road Map Team, NSSA, Open Phone: (703) 808-6040, DSN 898-6040.
(U) 21 November 1997
(U) Road Map Production Date: 23 June 2001