Abstract: An apparatus and method for combining multiple optical beams into mode-scrambled optical signals. In one embodiment, the apparatus includes a plurality of laser beam sources, each to produce a modulated optical beam. A plurality of input fiber segments, each comprising a multimode optical fiber core, are operatively coupled at one end to a respective laser source to receive a respective modulated optical beam. A multimode optical beam combiner is used to operatively couple the output ends of the input fiber segments to the input end of an output fiber segment having a multimode optical fiber core. The modulated optical beams produced by the laser beam sources are combined into a single mode-scrambled optical signal. The apparatus enables multiple optical beams having similar wavelengths to be combined to increase optical signal strength. It also enables multiple optical beams having different wavelengths to be combined to form a wavelength division multiplexed signal.

Abstract: Optical transceivers include a diffractive optical element (DOE) attached to a surface of a prism or other optical support. The DOE is configured to direct an input optical signal to a curved reflective surface or receive an output optical signal from the curved reflective surface at angles greater than a critical angle. In some examples, the optical support includes one or more curved reflective surfaces and the DOE is a hologram. Such optical transceivers can be provided with optical mounts configured for attachment to a building window.

Abstract: A microscope that preferentially displays either moving or stationary objects. This all-optical device operates in real-time using the coupling of optical beams in suitable nonlinear medium such as a photorefractive crystal of barium titanate. A holographic image is continuously written and compared with the real image. For the transient detection microscope any discrepancy between the two images is immediately visible. In the stationary object enhancing microscope stationary objects are enhanced and preferentially displayed.

Abstract: An improved spark igniter for use in a gas turbine engine wherein vent passages which are in the vicinity of the electrode are placed in communication with the ambient environment external to the engine during the ignition sequence causing fuel-air mixture to flow over the electrode as it is abstracted from the engine, thereby enhancing the probability of ignition.

Abstract: A centrally disposed vent is positioned adjacent the low pressure region of recirculating gases in a combustor or augmentor of the type used in gas turbine engines, allowing gas to be abstracted from the core of the recirculating region, thereby causing a reduction in static pressure, and a strengthening and stabilizing of the recirculating flow pattern. Combustion occurring in the recirculating gas is intensified by virtue of higher mixing rates, and flame stability is enhanced by virtue of increased stability of the recirculating flow pattern. The vent is shown employed in a premixing tube device for use in gas turbine engine main combustors. Alternative main combustor and augmentor combustor configurations are shown.

Abstract: This disclosure sets forth a combustion device for a power plant wherein a burner includes a central tubular section with an annular section located therearound. Air inlet means directs air to the burner. The central section comprises a premixing chamber and a combustion chamber for burning a fuel-air mixture while the annular section includes a catalytic reaction device. First tubular means directs air inwardly to said central tubular section for mixing with fuel where the fuel-air mixture is then burned. Additional air is added through second tubular means to the exhaust therefrom where it is then directed to one end of the annular section containing the catalytic reaction device. A transition member connects the exhaust end of the annular section to an outlet. Cooling louvers can be provided along this section if necessary. Further, a swirling device is located between the premixing chamber and combustion chamber for greater mixing of fuel and air.