Abstract: The present invention concerns an optical pumping system making use of a broad continuous absorption band in rare earth doped chalcogenide glasses. The absorption band is approximately 400 nm in width and extends from approximately 600 nm to 1000 nm. Through subjecting the glass to pumping light from an excitation source within the broad absorption band, photoluminescence emissions are produced. Size and strength of the pumping absorption band are such that great flexibility is provided in implementation of the excitation source. Specific embodiments of4 the present invention may utilize Er or Pr doped Ge.sub.33 As.sub.12 S.sub.55 or As.sub.2 S. Selection of the chalcogenide host may adjust the broad absorption band. As an example, a narrower gap chalcogenide glass, such as Ge.sub.28 Sb.sub.12 Se.sub.60, should extend the broad absorption band into the 1064 nm wavelength.

Abstract: The present invention concerns an optical pumping system using a broad continuous chalcogenide emission band of approximately 190 nm in width. The broad emission band is induced by the rare earth doping of a chalcogenide glass. Co-doping using Pr and Er produces a photoluminescence band extending from approximately 1510 nm to 1700 nm. Alternatively, separately Pr and Er doped samples exhibit emission bands considerably wider then the characteristic Pr(1620 nm) and Er (1550 nm) emission bands typically realized in doped oxide glasses. According to the present invention these broad bands are used to produce optical gain over the continuous broad 190 nm band. An excitation source subjects the glass to pumping light to stimulate the broad band emissions. Applied to an optical amplifier, optical signals entering the chalcogenide glass anywhere within the broad range will be amplified.

Abstract: A multiband photoconductive detector and method for simultaneously and separately detecting and distinguishing light or radiation from a large number of different wavelength bands is disclosed. The multiband photoconductive detector comprises a plurality of low energy gap semiconductor layers of preselected progressively decreasing thicknesses of a first material, a plurality of high energy gap semiconductor layers of a second material interleaved with the plurality of low energy gap semiconductor layers, and a plurality of pairs of electrical contacts respectively applied to the plurality of low energy gap semiconductor layers and adapted to respectively receive associated bias voltages to enable the plurality of low energy gap semiconductor layers to constitute a corresponding plurality of separate photoconductive detectors with a preselected plurality of different wavelength bands.

Abstract: An iron-doped indium phosphide or gallium arsenide semiconductor laser. The emiconductor material is doped when formed by uniformly distributing transition metal ions such as iron throughout the semiconductor. The concentration of the iron ions is from about 1.times.10.sup.15 to about 1.times.10.sup.18 ions per cubic centimeter, but is limited only by the solubility of iron indium phosphide or gallium arsenide. It has been determined that the greater the concentration of ions, the easier the laser emission is obtained. At liquid helium temperature, the iron-doped semiconductor laser will operate at a wavelength near 3 microns.

Abstract: A light-weight, night vision system which combines a reflected-light, imag device with an audio-monitored, far infrared detection device (HANSAM) for detecting long wavelength infrared radiation from warm bodies. The imaging device may be a near-infrared image converter or a visible image intensifier such as a "starlight scope". The Hansam is attached to the imager so that the center of its field of view coincides with the center of the field of view of the imager.