Abstract: A polarization-sensitive infrared image sensor (also termed a snapshot polarimeter) utilizing a 2-D array of polarizers to filter infrared light from a scene according to polarization, and a 2-D array of photodetectors (i.e. a focal plane array) to detect the filtered infrared light and generate polarization information which can be used to form a polarization-sensitive image of the scene. By forming each polarizer on an optical fiber in a fiber optic faceplate, the polarizers can be located facing a 2-D array of retarders to minimize diffraction effects of the infrared light. The optical fibers also guide the filtered infrared light to the photodetectors to reduce cross-talk in the polarization information. The polarizers can be formed as wire grid polarizers; and the retarders can be formed as subwavelength surface-relief gratings.

Abstract: A wavelength locker for use at more than one wavelength includes filters with different characteristics for a corresponding detector. The filters may be etalons having different free spectral ranges, e.g., having different apparent or real thicknesses. If more than three such filters are used outputting offset periodic signals, a reference detector may be eliminated and continuous operation over a wavelength range may be realized.

Abstract: A wavelength locker for use at more than one wavelength includes filters with different characteristics for a corresponding detector. The filters may be etalons having different free spectral ranges, e.g., having different apparent or real thicknesses. If more than three such filters are used outputting offset periodic signals, a reference detector may be eliminated and continuous operation over a wavelength range may be realized.

Abstract: A wavelength detector includes a beam splitter block that taps off two spatially separated beams and a linear filter in an optical path of one of the two beams. The linear filter may be provided on the beam splitter block. The linear filter may be a notch anti-reflective filter in the optical path of the application beam. One or both of the beams may be focused on to their respective detectors.

Abstract: An aspheric microlens, particularly a conic constant of the microlens, may be evaluated and this evaluation may be used to determine an optimal process for creating the aspheric microlens. Such evaluation may include a curve fitting or a numerical expression of the wavefront.

Abstract: A wavelength locker for use at more than one wavelength includes filters with different characteristics for a corresponding detector. The filters may be etalons having different free spectral ranges, e.g., having different apparent or real thicknesses. If more than three such filters are used outputting offset periodic signals, a reference detector may be eliminated and continuous operation over a wavelength range may be realized.

Abstract: Numerous features may be incorporated into a wavelength locker to reduce the noise inherent therein. These features may be used in any combination thereof. These features include avoiding the use of reflectors, using a diffractive splitter which outputs evanescent beams for diffractive orders greater than one, using anti-reflective coatings, using an opaque material with through holes for the light, and designing the wavelength locker to be used at a tilt.

Abstract: A wavelength detector includes a beam splitter block that taps off two spatially separated beams and a linear filter in an optical path of one of the two beams. The linear filter may be provided on the beam splitter block. The linear filter may be a notch anti-reflective filter in the optical path of the application beam. One or both of the beams may be focused on to their respective detectors.

Abstract: Numerous features may be incorporated into a wavelength locker to reduce the noise inherent therein. These features may be used in any combination thereof.

Abstract: An aspheric microlens, particularly a conic constant of the microlens, may be evaluated and this evaluation may be used to determine an optimal process for creating the aspheric microlens. Such evaluation may include a curve fitting or a numerical expression of the wavefront.