Abstract: An interferometric environmental monitoring system having an active beam and a reference beam, each following an optical path, a detector system including a detector assembly, a pair of reflecting elements, the first reflecting element receiving the active beam and reflecting it, the second reflecting element receiving the reference beam and reflecting it. The reflected active and reflected reference beams are recombined into a recombined beam, which is directed to the detector assembly. The detector assembly monitors the central fringe of an interference pattern formed by interference when combining the active and the reference beams and providing an output signal related to the movement of the central fringe. The output signal being utilized to provide a signal representative of a condition which measurably affects the active beam.

Abstract: An improved method of manufacturing holographic elements for solar concentrator, which is a necessity for the future of viable low cost solar power. Utilizing extremely high relative humidity levels during the fabrication of holographic plates, exposing the holographic plate to electromagnetic radiation at particular humidity levels, and having a relative angle between recording beams during exposure makes it possible to fabricate high efficiency holographic elements that diffract over a broad bandwidth. These high efficiency, broad bandwidth holographic elements are most effective in certain solar concentrating systems.

Abstract: A high efficiency, broad bandwidth, volume holographic element for diffraction windows. This holographic element is fabricated so that it can passively track and diffract solar radiation throughout the course of a day. Such a hologram can effectively illuminate the interior of a building or room with sunlight. This invention can reduce both lighting costs and the cooling costs associated with generating artificial light.

Abstract: The Index Interferometric Instrument is a highly accurate instrument which can be utilized to measure the index of refraction, the dispersion, and the index profile of materials. The instrument provides the data necessary to measure the index of refraction of materials to five significant figures. The index profile can be measured at any chosen wavelength without any sample preparation. The instrument utilizes a 10 nm to a 400 nm bandwidth light source and a light source with a bandwidth of less than 10 nm in combination with an interferometer. Each light source creates interference patterns from the sample and a reference mirror which can be used to accurately calculate the index of refraction of an entire sample at any given point on the sample.