44 results about "Spectral window" patented technology

A Fabry-Perot cavity comprised of three-dimensional photonic crystal structures is disclosed. The self-assembly of purified and highly monodispersed microspheres is one approach to the successful operation of the device for creating highly ordered colloidal crystal coatings of high structural and optical quality. Such colloidal crystal film mirrors offer high reflection with low losses in the spectral window of the photonic band gap that permit Fabry-Perot resonators to be constructed with high resolving power, for example, greater than 1000 or sharp fringes that are spectrally narrower than 1.0 nm. The three-dimensional photonic crystals that constitute the Fabry-Perot invention are not restricted to any one fabrication method, and may include self-assembly of colloids, layer-by-layer lithographic construction, inversion, and laser holography. Such photonic crystal Fabry-Perot resonators offer the same benefits of high reflection and narrow spectral band responses available from the use of multi-layer dielectric coatings. However, the open structure of three-dimensional photonic crystal films affords the unique ability for external media to access the critical reflection layers and dramatically alter the Fabry-Perot spectrum, and provide means for crafting novel laser, sensor, and nonlinear optical devices. This open structure enables the penetration of gas and liquid substances, or entrainment of nano-particles or biological analytes in gases and liquids, to create subtle changes to the colloidal mirror responses that manifest in strong spectral responses in reflection and transmission of the collective Fabry Perot response.

A semiconductor laser comprises two optical ring resonators, each comprising an optical waveguide electrically pumped to provide optical gain. The two ring resonators have different round-trip optical path lengths, and are coupled to each other through a half-wave optical coupler. The half-wave optical coupler has a predetermined cross-coupling coefficient and a 180-degree cross-coupling phase. The cross-coupling coefficient is substantially less than the self-coupling coefficients in order to achieve an optimal single-mode selectivity of the laser. The first ring resonator has an optical path length such that its resonant wavelengths correspond to a set of discrete operating channels. The second ring resonator has a slightly different length so that only one resonant wavelength coincides with one of the resonant wavelengths of the first ring resonator over the operating spectral window. The lasing action occurs at the common resonant wavelength. In operation, at least a portion of the optical waveguide in each of the first and the second ring resonators are forward biased to provide substantially equal round-trip optical gains. The second ring resonator is tuned by varying the effective refractive index of a portion of the waveguide through an electrical means, resulting in wavelength switching among the set of discrete operating wavelengths as determined by the first ring resonator.

A radiation dosimetry apparatus and method use a scintillating optical fiber array for detecting dose levels. The scintillating optical fiber detectors generate optical energy in response to a predetermined type of radiation, and are coupled to collection optical fibers that transmit the optical energy to a photo-detector for conversion to an electrical signal. The detectors may be embedded in one or more modular, water-equivalent phantom slabs. A repeatable connector couples the collection fibers to the photo-detector, maintaining the fiber ends in a predetermined spatial relationship. The detector fibers may be distributed as desired in a three-dimensional detection space, and may be oriented with their longitudinal axes at different orientations relative to a transmission axis of an incident radiation beam. A calibration method uses two measurements in two spectral windows, one with irradiation of the scintillator at a known dose and one with only irradiation of the collection fiber.

An improved system for visual inspection of substrates coated with paints and polymers is disclosed. Painted substrates can be inspected for environmental and physical damage such as corrosion and cracks without removing the paint. The present invention provides the ability to maximize paint thickness penetration. This is accomplished with a spectral bandpass filter that rejects reflected light from the coating opaque bands, while allowing light in the paint window to pass to an IR detector such as an IR camera focal plane. The narrow bandpass range enhances the ability for IR imaging to see through thicker paint layers and improves the contrast over standard commercial IR mid-wave cameras. The bandpass may be adjusted to coincide with the full spectral window of the paint, consistent with the ability of the imaging focal plane to detect light in the spectral region.

A monolithically integrated wavelength switchable laser comprises three coupled Fabry-Perot cavities. The length and consequently the free spectral range of the first cavity are designed such that the resonant peaks correspond substantially to a set of discrete operating wavelengths separated by a constant channel spacing. The second cavity has a slightly different length so that only one resonant peak coincides with one of the resonant peaks of the first cavity over the spectral window of the material gain. The lasing action occurs at the common resonant wavelength. The two cavities are coupled through a third short cavity that produces a certain coupling loss and phase relationship between the first and the second cavities in order to achieve an optimal mode selectivity of the combined cavity laser. In operation, both the first and the second cavities are forward biased to provide optical gains for the laser action. The second cavity is tuned by varying the refractive index of at least a portion of the waveguide within the cavity through an electrical means, resulting in wavelength switching of the laser among the set of discrete operating wavelengths as determined by the first cavity.

The invention discloses a spectral electrolytic cell suitable for in-situ characterization of a Raman spectrum and relates to a spectral electrolytic cell. The spectral electrolytic cell is provided with a spectral electrolytic cell body, a top cover, an electrode sleeve, a reference electrode connection end, a spectral window sheet, limiting rings, limiting adjustment gaskets, reference electrode sealing covers, a counter electrode and a working electrode, wherein the cell body is connected with the top cover; window sheet sealing rings are fixed on the top cover; a first hole is formed in the middle of the cell body; the electrode sleeve is arranged in the first hole; a second hole is formed in the bottom in the cell body and is connected with the reference electrode connection end; a through hole is formed in the electrode sleeve; the upper end of the reference electrode connection end is connected with the reference electrode sealing covers; the spectral window sheet is arranged at the bottom in the top cover; small holes are formed in the middles of the reference electrode sealing covers; a third hole is formed in the side edge of the cell body; the counter electrode is arranged in the third hole; the limiting rings and the limiting adjustment gaskets are arranged at the periphery of the electrode sleeve; one end of the counter electrode is a sphere; a trench is formed in the bottom of the top cover; a gas storage tank is arranged beside the trench; a gas exhaust hole is formed in the upper end of the gas storage tank.

The invention relates to a pre-calculating recovery method based on distance self-adaptive route and spectrum distribution. The method includes that an elastic optical interconnection data center network configuration is defined by means of design software, a network control plane and a data forwarding plane are separated, a controller function module and an OpenFlow protocol are expanded to realize the function of rapid and flexible customization of network; according to the number of spectral gaps on the link, the network topology is divided into layers and a spectral window layered auxiliary graph model is constructed, a proper modulation format is selected based on distance self-adaption, the business route and spectrum distribution is carried out based on the spectral window layered auxiliary graph model; and when the fault business is recovered, a recovered route is calculated for the business in advance by means of pre-calculating recovery technology, and when the business has faults, network resources are opened for the interrupted business by means of a pre-calculating recovery scheme and the recovered route can be rapidly established. According to the method, the dual restraint of spectrum adjacency and continuity can be met, obstruction can be prevented, and meanwhile, the fault business can be rapidly recovered, and the integral performance of the network can be improved.

A method for altering fluorescent emissions of particles includes setting the particles in motion and exposing the moving particles to light such that fluorescent intensities of the particles are lessened isotropically and substantially simultaneously. Another method includes measuring fluorescent emissions of particles, determining the measured fluorescent emissions do not collectively fit within a first predetermined range of fluorescent values, and exposing the particles to one or more incidents of light that are configured to cooperatively alter the fluorescent emissions of the particles to be within a second predetermined range of fluorescent values. An embodiment of an apparatus includes a vessel configured to contain a plurality of particles and a means for setting the particles in motion. The apparatus further includes an illumination subsystem configured to direct light toward the vessel and at a spectral window (i.e., wavelength or band of wavelengths) which is configured to isotropically and substantially simultaneously lessen the fluorescent emissions of each of the particles.