Abstract: Techniques are provided to detect and/or replace anomalous pixels. In one example, a method includes receiving an image frame comprising a plurality of pixels having associated pixel values. The method also includes selecting a kernel of the pixels comprising a center pixel and a plurality of neighbor pixels. The method also includes, if the center pixel value exhibits an anomalous pixel condition, calculating a replacement pixel value using a gradient associated with at least a subset of pixel values of the neighbor pixels. Additional methods and systems are also provided.

Abstract: A wavelength selective structure for selectively reflecting or absorbing incident electromagnetic visible or infrared radiation. The wavelength selective structure includes a wavelength selective structure with a plurality of layers, including a compound layer forming a plurality of surface elements, an electrically isolating intermediate layer, wherein the compound layer is in contact with a first surface of the electrically isolating intermediate layer, and a continuous electrically conductive layer in contact with a second surface of the electrically isolating intermediate layer. The compound layer includes at least one metallic layer and at least one dielectric layer. The selective surface has at least one resonance band for selectively reflecting or absorbing visible or infrared radiation based on a resonant electromagnetic coupling between the plurality of surface elements and the continuous electrically conductive layer.

Abstract: A tunable electromagnetic radiation device that includes a wavelength selective structure including a plurality of layers. The plurality of layers includes a compound layer including a plurality of surface elements, an electrically isolating intermediate layer, and a continuous electrically conductive layer. The compound layer includes at least one metallic layer or metallic-like layer and at least one dielectric layer and is in contact with a first surface of the electrically isolating intermediate layer. The continuous electrically conductive layer is in contact with a second surface of the electrically isolating intermediate layer. The wavelength selective structure has at least one reflective or absorptive resonance band. The tunable electromagnetic radiation device further includes an electrode in electrical contact with at least one of the compound layer, the electrically isolating intermediate layer, and the continuous electrically conductive layer.

Abstract: A tunable electromagnetic radiation device that includes a wavelength selective structure comprising a plurality of layers. The plurality of layers includes a compound layer comprising a plurality of surface elements, an electrically isolating intermediate layer, and a continuous electrically conductive layer. The compound layer includes at least one metallic layer or metallic-like layer and at least one dielectric layer and is in contact with a first surface of the electrically isolating intermediate layer. The continuous electrically conductive layer is in contact with a second surface of the electrically isolating intermediate layer. The wavelength selective structure has at least one reflective or absorptive resonance band. The tunable electromagnetic radiation device further includes an electrode in electrical contact with at least one of the compound layer, the electrically isolating intermediate layer, and the continuous electrically conductive layer.

Abstract: A synchronized infrared beacon/infrared detector system. The system may include (A) an infrared beacon module configured to generate a time-varying encoded infrared signal, (B) an infrared detector module configured to capture the encoded infrared signal generated by the beacon module, (C) a synchronizer configured to generate a synchronization signal that controls timing of the beacon module and the detector module, and (D) a processor, in communication with the detector module, configured to analyze the infrared signal captured by the detector module. The infrared signal may be modulated at frequencies undetectable by human vision. The synchronizer signal may be produced independent of the capture of, and without input from, the infrared signal.

Abstract: A wavelength selective structure for selectively reflecting or absorbing incident electromagnetic visible or infrared radiation. The wavelength selective structure includes a wavelength selective structure with a plurality of layers, including a compound layer forming a plurality of surface elements, an electrically isolating intermediate layer, wherein the compound layer is in contact with a first surface of the electrically isolating intermediate layer, and a continuous electrically conductive layer in contact with a second surface of the electrically isolating intermediate layer. The compound layer includes at least one metallic layer and at least one dielectric layer. The selective surface has at least one resonance band for selectively reflecting or absorbing visible or infrared radiation based on a resonant electromagnetic coupling between the plurality of surface elements and the continuous electrically conductive layer.

Abstract: A tunable electromagnetic radiation device that includes a wavelength selective structure comprising a plurality of layers. The plurality of layers includes a compound layer comprising a plurality of surface elements, an electrically isolating intermediate layer, and a continuous electrically conductive layer. The compound layer includes at least one metallic layer or metallic-like layer and at least one dielectric layer and is in contact with a first surface of the electrically isolating intermediate layer. The continuous electrically conductive layer is in contact with a second surface of the electrically isolating intermediate layer. The wavelength selective structure has at least one reflective or absorptive resonance band. The tunable electromagnetic radiation device further includes an electrode in electrical contact with at least one of the compound layer, the electrically isolating intermediate layer, and the continuous electrically conductive layer.

Abstract: A synchronized infrared beacon/infrared detector system. The system may include (A) an infrared beacon module configured to generate a time-varying encoded infrared signal, (B) an infrared detector module configured to capture the encoded infrared signal generated by the beacon module, (C) a synchronizer configured to generate a synchronization signal that controls timing of the beacon module and the detector module, and (D) a processor, in communication with the detector module, configured to analyze the infrared signal captured by the detector module. The infrared signal may be modulated at frequencies undetectable by human vision. The synchronizer signal may be produced independent of the capture of, and without input from, the infrared signal.

Abstract: Methods and apparatus for providing a tunable absorption-emission band in a wavelength selective device are disclosed. A device for selectively absorbing incident electromagnetic radiation includes an electrically conductive surface layer including an arrangement of multiple surface elements. The surface layer is disposed at a nonzero height above a continuous electrically conductive layer. An electrically isolating intermediate layer defines a first surface that is in communication with the electrically conductive surface layer. The continuous electrically conductive backing layer is provided in communication with a second surface of the electrically isolating intermediate layer. When combined with an infrared source, the wavelength selective device emits infrared radiation in at least one narrow band determined by a resonance of the device. In some embodiments, the device includes a control feature that allows the resonance to be selectively modified.

Abstract: Methods and apparatus for providing a tunable absorption-emission band in a wavelength selective device are disclosed. A device for selectively absorbing incident electromagnetic radiation includes an electrically conductive surface layer including an arrangement of multiple surface elements. The surface layer is disposed at a nonzero height above a continuous electrically conductive layer. An electrically isolating intermediate layer defines a first surface that is in communication with the electrically conductive surface layer. The continuous electrically conductive backing layer is provided in communication with a second surface of the electrically isolating intermediate layer. When combined with an infrared source, the wavelength selective device emits infrared radiation in at least one narrow band determined by a resonance of the device. In some embodiments, the device includes a control feature that allows the resonance to be selectively modified.

Abstract: Methods and apparatus for providing a tunable absorption-emission band in a wavelength selective device are disclosed. A device for selectively absorbing incident electromagnetic radiation includes an electrically conductive surface layer including an arrangement of multiple surface elements. The surface layer is disposed at a nonzero height above a continuous electrically conductive layer. An electrically isolating intermediate layer defines a first surface that is in communication with the electrically conductive surface layer. The continuous electrically conductive backing layer is provided in communication with a second surface of the electrically isolating intermediate layer. When combined with an infrared source, the wavelength selective device emits infrared radiation in at least one narrow band determined by a resonance of the device. In some embodiments, the device includes a control feature that allows the resonance to be selectively modified.

Abstract: Methods and apparatus for providing a tunable absorption-emission band in a wavelength selective device are disclosed. A device for selectively absorbing incident electromagnetic radiation includes an electrically conductive surface layer including an arrangement of multiple surface elements. The surface layer is disposed at a nonzero height above a continuous electrically conductive layer. An electrically isolating intermediate layer defines a first surface that is in communication with the electrically conductive surface layer. The continuous electrically conductive backing layer is provided in communication with a second surface of the electrically isolating intermediate layer. When combined with an infrared source, the wavelength selective device emits infrared radiation in at least one narrow band determined by a resonance of the device. In some embodiments, the device includes a control feature that allows the resonance to be selectively modified.

Abstract: Methods and apparatus for providing a tunable absorption band in a wavelength selective surface are disclosed. A device for selectively absorbing incident electromagnetic radiation includes an electrically conductive surface layer including an arrangement of multiple surface elements. The surface layer is disposed at a nonzero height above a continuous electrically conductive layer. An electrically isolating intermediate layer defines a first surface that is in communication with the electrically conductive surface layer. The continuous electrically conductive backing layer is provided in communication with a second surface of the electrically isolating intermediate layer. The arrangement of surface elements couples at least a portion of the incident electromagnetic radiation between itself and the continuous electrically conductive backing layer, such that the resonant device selectively absorbs incident radiation, and reflects a portion of the incident radiation that is not absorbed.

Abstract: An infrared emitter, which utilizes a photonic crystal (PC) structure to produce electromagnetic emissions with a narrow hand of wavelengths, includes a semiconductor material layer, a dielectric material layer overlaying the semiconductor material layer, and a metallic material layer having an inner side overlaying the dielectric material layer. The semiconductor material layer is capable of being coupled to an energy source for introducing energy to the semiconductor material layer. An array of surface features are defined in the device in a periodic manner or quasi-periodic. The emitter device is adapted to emit electromagnetic energy having spectral characteristics determined by parameters of the periodically distributed surface features, the parameters including shape, size, depth, distribution geometry, periodicity, material properties and defects.

Abstract: An absorption spectroscopy apparatus including an elliptical mirror centered on the midpoint between a source/detector and a mirror. The cavity between the elliptical mirror and the source/bolometer and mirror defines an interior volume of a sample cell. Electromagnetic radiation from the source/detector travels along a multi-segment path starting from the source/bolometer toward the elliptical mirror, reflecting off of the elliptical mirror and traveling toward the mirror, reflecting off of the mirror and traveling back toward the elliptical mirror and finally reflecting off the elliptical mirror for a second time and returning toward the source/bolometer. The multiple reflections combined with the focusing effects of the elliptical mirrored surface result in an efficient sampling device. Among other aspects and advantages, the apparatus of the present disclosure is able to use incoherent, non-collimated light sources while maintaining high optical throughput efficiencies.

Abstract: An infrared emitter, which utilizes a photonic crystal (PC) structure to produce electromagnetic emissions with a narrow hand of wavelengths, includes a semiconductor material layer, a dielectric material layer overlaying the semiconductor material layer, and a metallic material layer having an inner side overlaying the dielectric material layer. The semiconductor material layer is capable of being coupled to an energy source for introducing energy to the semiconductor material layer. An array of surface features are defined in the device in a periodic manner or quasi-periodic. The emitter device is adapted to emit electromagnetic energy having spectral characteristics determined by parameters of the periodically distributed surface features, the parameters including shape, size, depth, distribution geometry, periodicity, material properties and defects.