An interferometer comprises a non-uniform beam splitter (34) which splits an incoming beam (30) of energy into two beams (36, 38). The two beams (36, 38) are taken from parts of the incoming beam (30) which overlap. The two beams (36, 38) are fed spacially separated energy feeds (44, 46) and then fed to a comparator to produce sum and difference channels (54, 58). The sum and difference channels (54, 58) are guided to a means for detecting a difference in phase (60) between the sum and difference channels (54, 58).
A polarizing photonic band gap system has a photonic crystal emitter. The photonic crystal emitter has a crystal end surface. The photonic crystal emitter is configured to generate electromagnetic energy having a wavelength .lamda.. The system has a polarizer. The polarizer is connected to the photonic crystal emitter. The polarizer has a polarizer surface. The polarizer surface is located within a distance of said crystal end surface. The distance is sufficient to quantum mechanically couple the polarizer surface with said crystal end surface at the wavelength .lamda..
The device for interferometric recombination of electromagnetic beams includes one or more modules each including: at least one splitter assembly (3.sub.1) incorporating a beam splitter (5) provided with interceptor means positioned to split an incident beam into portions, one of said portions (f.sub.1) passing through the splitter via an aperture provided for that purpose and another portion at least being intercepted by a surface prepared either to reflect it in a determined direction or alternatively to absorb it; at least one coupler (4.sub.2) arranged to recombine the beams that it receives interferometrically, this coupler being obtained by localized splicing of waveguides in accordance with an X or Y structure, each waveguide receiving a beam from a different collector, at least one of the beams corresponding to one of the portions resulting from the splitting effected by a beam splitter.
An apparatus for generating linear patterns of light comprises a light source emitting a first light beam. An anamorphic system is positioned downstream of the light source and is adapted to receive the first light beam of the light source for concentrating the first light beam such that the first light beam would project a first linear pattern on a far field. A diffractive optical element is positioned downstream of the anamorphic system for receiving and diffusing the first light beam of the anamorphic system a plurality of second light beams. The plurality of second light beams overlap one another at least partially so as to project a second linear pattern on the far field of altered intensity with respect to the first linear pattern.
A system for generating a source of broadband light includes, in one embodiment, a plurality of light sources such as SLEDs or edge-emitting luminescent diodes (ELEDs) whose outputs are combined in at least one combiner unit. The combiner unit combines light from a plurality of light sources into a single mode output beam. In one embodiment, the single mode output beam is the input beam to an interferometer for optical coherence tomography. In another embodiment, a time-gain compensation (TGC) unit is in communication with the plurality of light sources. The TGC unit controls the plurality of light sources independently and simultaneously. In one embodiment, control of the plurality of light sources by the TGC unit is in synchrony with the variation in optical delay in the reference arm of the interferometer. The TGC unit may feature, for example, a modulated current regulator.
7412175 - Interferometric polarization control - Owned by The United States of America as represented by the Administrator of the National Aeronautics and Space Administration (Washington, DC) N/A
A signal conditioning module provides a polarimeter capability in a photometric system. The module may include multiple variable delay polarization modulators. Each modulator may include an input port, and a first arm formed to include a first reflector and first rooftop mirror arranged in opposed relationship. The first reflector may direct an input radiation signal to the first rooftop mirror. Each modulator also may include an output port and a second arm formed to include a second reflector and second rooftop mirror arranged in opposed relationship. The second reflector can guide a signal from the second rooftop mirror towards the output port to provide an output radiation signal. A beamsplitting grid may be placed between the first reflector and the first rooftop mirror, and also between the second reflector and the second rooftop mirror. A translation apparatus can provide adjustment relative to optical path length vis-a-vis the first arm, the second arm and the grid.
