Abstract: A system and method for viewing an object in a visually obscured environment includes a laser for generating a beam of light which is directed at the object. A pulse generator generates a reference pulse which triggers the laser and also a triggers a range generator which generates a range window positioned at a desired range. A gated optical detector (1) receives reflected light from the object, (2) receives the range window from the range generator, and (3) produces a gated optical output which contains reflections from ranges corresponding with the range window. A display is connected to the gated optical detector for displaying the gated optical output. In one embodiment, the transmitted light beam is polarized, and the received light beam passes through a selectable polarizing filter. In another embodiment, a plurality of received reflected light returns are integrated into a combined image.

Abstract: A narrowband filter with a wide acceptance angle which utilizes two holographic filter elements connected in series. The filter blocks light outside of a narrow spectral band of interest, while enabling light to be seen over a wide range of angles incident on the filter.

Abstract: A system and method for viewing objects at a fire scene allows fire fighters to view objects, including persons, in a smoke and fire filled environment. The present invention utilizes two different techniques to discriminate reflections from an object from scattered reflections from smoke and fire. In one embodiment of the invention, the coherent nature of laser light is employed to pick out objects. Another embodiment of the invention utilizes a time-gated approach to select reflections from objects which are located a specific distance from the laser transmitter.

Abstract: The present invention is directed to a monochromator device which uses single grating volume holograms. The holograms collect light of varying wavelengths such as polychromatic light, and separate one particular wavelength of interest. A wide wavelength spectrum can be targeted, either by angularly tuning the holograms, or by using an array of holograms each of which is tuned to a different center wavelength. The large aperture and high angular dispersion of the volume holograms provides a higher light throughput than that of prior art monochromators. The present invention can be used anywhere that efficient separation of polychromatic light into its narrowband components is required. The monochromator may be placed immediately before a light source, or before other optical or signal processing devices to provide the filtered wavelength of light input to such devices.

Abstract: A narrowband, tunable filter with a wide acceptance angle utilizes two holographic filter elements connected in series. The filter blocks light outside of a narrow spectral band of interest, while enabling light to be seen over a wide range of angles incident on the filter.

Abstract: A system and method for viewing objects at a fire scene allows fire fighters to view objects, including persons, in a smoke and fire filled environment. The present invention utilizes two different techniques to discriminate reflections from an object from scattered reflections from smoke and fire. In one embodiment of the invention, the coherent nature of laser light is employed to pick out objects. Another embodiment of the invention utilizes a time-gated approach to select reflections from objects which are located a specific distance from the laser transmitter.