USA As Represented by Secretary of the Navy

Melvin R Kruer

Leon Esterowitz

Filbert J Bartoli

Roger E Allen

Van O Nicolai

Hans P Jenssen

Lawrence S Goldberg

Arthur Linz

Michael Colbert

Dale C LinneVonBerg

Russell Smith

An apparatus includes an image buffer, a graphics buffer, a memory, a router, and a sensor interface. The apparatus further includes a memory controller for controlling transfer of image data from the image buffer to the memory via the router and for controlling transfer of graphics data from the memory to the graphics buffer via the router. The apparatus also includes an image controller simultaneously operable with the memory controller for controlling transfer of the image data from the sensor interface to the image buffer. Optionally, the sensor interface comprises a receiver and a transmitter. Optionally, the apparatus further includes a header buffer, and a header controller simultaneously operable with the memory controller for controlling transfer of header data from the sensor interface to the header buffer. The apparatus optionally further includes a sensor for communicating with the header controller via the sensor interface.

Airborne real time image exploitation system (ARIES)

A method of achieving inversion in solid-state rare-earth materials for blue-green laser operation. A XeF excimer laser is used to pump a matching transition in divalent ytterbium in a host material. The host material is co-doped with a trivalent ion such as praseodymium (Pr.sup.3+) so that energy transfer to the trivalent ion will take place. Laser action is then from the Pr.sup.3+ ion. Alternative matching absorption transitions also occur in the trivalent rare-earth ions of Tb, Dy, Ho, and Nd.

Excimer-pumped blue-green laser

A solid-state laser operative in the mid infrared region (3-5 .mu.m) comprises a YLF laser including a trivalent terbium activator which is pumped by a resonant external laser source (Ho:YLF, 2.06 .mu.m laser) to directly populate the upper laser level which achieves inversion before non-radiative decay depletes the initial laser-level population. The initial laser manifold that is externally pumped is the .sup.7 F.sub.2 manifold. Inversion is then between the .sup.7 F.sub.3 and .sup.7 F.sub.5 manifolds and laser oscillation at 4.1 .mu.m is obtained.

Resonantly pumped mid-ir laser

An efficient, four-level, blue-green, excimer-pumped laser which is opera at room temperature. The laser element includes a CaWO.sub.4 crystal which has been codoped with trivalent thulium activator ions and divalent ytterbium sensitizer ions. Energy is transferred from the absorbing Yb.sup.2+ ions to the Tm.sup.3+ ions and the laser transition is from the .sup.1 D.sub.2 multiplet to the ground .sup.3 F.sub.4 of the Tm.sup.3+ ion. This transition terminates on an excited state; therefore, the laser action is four-level.

Excimer-pumped four level blue-green solid state laser

A method for determining the compensation density of narrow-gap semiconductors. Photo-excited carriers are generated by uniformily irradiating a sample with a laser pulse of a particular density and pulse width for a particular time length and at a low sample temperature. The laser wavelength is chosen with a photon energy sufficiently high that carriers are excited from the conduction band by normal intrinsic absorption (one-photon absorption). Subsequent to the laser pulse, conductivity-voltage measurements are taken as a function of time during the photo-electron decay. Such measurements are made for different applied source-detector connections on the same sample with identical pulse-time values for each different correction. The sample is then laser-pulsed as before with a magnetic field normal to the sample surface to obtain Hall-voltage measurements. The measurements are averaged for the same time duration and the average of all curves are used in the determination. From the conductivity-voltage measurments and the Hall-voltage measurements, the mobility .mu., and carrier density n, can be determined. The time dependence of .mu. and n measured during the photo-electron decay yields values of mobility as a function of n. A mobility vs carrier density curve is then prepared and compared with previously prepared curves to obtain a match and thereby determine the quality of the sample. Thus characterization of n-type narrow-gap semiconductors can be made.

Method for determining the compensation density in n-type narrow-gap

Improvements in Praseodymium solid state YLF lasers operating in the blueeen spectral region at room temperature and providing short pulses useful for underwater communication and detection systems. A dye laser with a narrow spectral output matched to the absorption spectra of the solid state laser is provided as a laser pump. The Pr doped YLF crystal of the solid state laser is physically oriented so it can be longitudinally pumped by light polarized parallel to the c-axis of the crystal, and the solid state laser is equipped with special spectrally selective mirrors. The foregoing and other modifications of prior Pr solid state laser systems provide increased efficiency and power output.

Praseodymium blue-green laser system

A method for determining in situ the thermal conductances of bonding layers of detectors in infrared detector arrays for quality selection of preferred detector arrays. Each detector of the array is heated successively by laser pulses of variable pulse width and the thermally-induced change in detector resistance is measured as a function of time after each laser pulse and converted directly to its corresponding temperature. Using measured values of detector resistance as a function of temperature for each detector, one can obtain the time-dependence of the detector temperature following each laser pulse for each detector of the array.

Determination of thermal conductances of bonding layers in infrared

A photoconductive detector comprising a thin film of photoconductive material deposited on a thin substrate of high thermal conductivity having a surface area that is large relative to the detector's absorbing surface area. The back surface of the substrate is metalized and soldered to a high-thermal-conductivity, large-thermal-mass heat buffer which is coupled to a heat sink. The resulting detector is hardened against damage resulting from laser irradiation.

Room-temperature, thin-film, PbS photoconductive detector hardened

A method of determining thermal constants of bonding layers of an infrared ensor which comprises cooling a bonded layer sensor to 77.degree.K and then heating the sensor by a quick pulse of heat. The electrical resistance of the sensor is measured and the measurement continued to determine a thermal profile. The measured thermal profile is compared with a known profile to determine thickness of the bonding layers and the material layers.

Growing community of inventors

Oxon Hill, MD, United States of America

Melvin R Kruer