Abstract: A domestic water recycling system using a combination of an optical detector to detect certain smaller sized (non-filtered) contaminants and a filter to remove larger sized (filtered) contaminants provides an efficient wastewater recycling system. Optical detection of contaminants determines whether water is discharged or filtered and recycled. The optical detection system can use several discrete optical wavelengths that are passed through the fluid, and can determine a relative presence of the contaminants based on the resulting wavelength response. A recycling shower using optical detection, an electronically actuated directional device and pump and a controller allows for automatic recycling or discharging of water without requiring user input. The system may include a turbulence reduction baffle in a collection chamber, and a disinfection unit for the recycled water.

Abstract: A broadband optical accumulator and tunable narrowband optical source use a microstructured optical fiber into which optical energy is coupled at a first wavelength. The input optical energy is spectrally broadened as it propagates through the fiber, and the output signal is directed to a wavelength separator such as a Bragg grating. A narrowband portion of the output signal is redirected by the grating, while the remainder is reinjected into the fiber. Adjustment of the output wavelength band may be accomplished by changing the incidence angle of the output signal by pivoting the grating. The grating may be located in a housing and surrounded by index matching fluid, and the narrowband portion of the output signal isolated by the grating may be redirected to an output location by a reflector that moves with pivoting of the grating.

Abstract: The present invention concerns a method and camera for obtaining a high-contrast image of a predetermined target present in an area under observation. The method involves obtaining an in-band image of the observation area including the target using a filter whose bands are aligned with selected characteristic wavelength bands of the target and an out-of-band image of the observation area excluding the target using the filter with its bands non-aligned with the selected characteristic wavelength bands of the target. Processing of the in-band and out-of-band images results in a high-contrast image highlighting the presence of the target in the observation area and thereby allowing its detection and monitoring.

Abstract: A laser induced breakdown spectroscopy (LIBS) system uses discrete optical filters for isolated predetermined spectral components from plasma light created by ablation of a sample. Independent detection elements may be used for detecting the magnitude for each spectral component. A first spectral component may include a characteristic wavelength of the sample, while a second spectral component may be a portion of a background continuum. The filters may include volume Bragg gratings and the detectors may be photodiodes. A detector that detects plasma light remaining after the isolation of the predetermined spectral components may be used together with a signal acquisition controller to precisely control the initiation and termination of signal acquisition from each of the detection elements. The system may also have optics including a collimating lens through which passes both the initial plasma light and the isolated spectral components.

Abstract: A notch filter system, where multiple filter passes of a light signal may be effected for removing a target spectral component from the light signal, is provided. Advantageously, the notch filter system may be tunable. A cascade notch filter system is provided which includes multiple notch filters arranged in a cascade, each of the filters having spectral filtering characteristics and being disposed in the path of the light signal at an appropriate filter angle so that the target spectral component is filtered out of the light signal as the light signal passes therethrough. A multipass notch filter system is provided which includes a notch filter having spectral filtering characteristics, and an optical assembly for directing the light signal for multiple filter passes through the filter at an appropriate angle, so that the target spectral component is filtered out of the light signal as the light signal passes through the filter.

Abstract: The present invention relates to tunable filters. More specifically, the present invention pertains to a method and apparatus that allows tuning of a wavelength over a large optical band. The disclosed system and method allows an arbitrary wavelength selection of an incoming beam of light. The disclosed system and method may be used in imaging systems like telescopes or microscopes, or for point sources like laser or optical fibers. Further, in the case of optical fibers, it may be used as an add/drop filter.

Abstract: The present invention concerns a method and camera for obtaining a high-contrast image of a predetermined target present in an area under observation. The method involves obtaining an in-band image of the observation area including the target using a filter whose bands are aligned with selected characteristic wavelength bands of the target and an out-of-band image of the observation area excluding the target using the filter with its bands non-aligned with the selected characteristic wavelength bands of the target. Processing of the in-band and out-of-band images results in a high-contrast image highlighting the presence of the target in the observation area and thereby allowing its detection and monitoring.

Abstract: Narrow-line holographic filters that can include a plurality of lines and that can be structured to provide a large aperture device. Materials that can be used to construct filters include glasses, photorefractive crystals such as lithium niobate and photorefractive thick polymers. The filters are fabricated by assembling a plurality of elements having the same one or more narrow line holographic filter patterns written thereon, in mutual orientation such that each element has a surface defined by a length and a width adjacent a corresponding surface of a neighboring element, and has a surface defined by a thickness and one of a length and a width accessible to impinging illumination. Filters exhibiting a plurality of characteristic narrow lines, and having arbitrarily large apertures can be fabricated. Methods of fabricating and using the filters are described.

Abstract: Narrow-line holographic filters that can include a plurality of lines and that can be structured to provide a large aperture device. Materials that can be used to construct filters include glasses, photorefractive crystals such as lithium niobate and photorefractive thick polymers. The filters are fabricated by assembling a plurality of elements having the same one or more narrow line holographic filter patterns written thereon, in mutual orientation such that each element has a surface defined by a length and a width adjacent a corresponding surface of a neighboring element, and has a surface defined by a thickness and one of a length and a width accessible to impinging illumination. Filters exhibiting a plurality of characteristic narrow lines, and having arbitrarily large apertures can be fabricated. Methods of fabricating and using the filters are described.

Abstract: The present invention relates to tunable filters. More specifically, the present invention pertains to a method and apparatus that allows tuning of a wavelength over a large optical band. The disclosed system and method allows an arbitrary wavelength selection of an incoming beam of light. The disclosed system and method may be used in imaging systems like telescopes or microscopes, or for point sources like laser or optical fibers. Further, in the case of optical fibers, it may be used as an add/drop filter.