Abstract: Systems and methods that combine forward-model image reconstruction techniques with tomographic estimation of three-dimensional atmospheric turbulence to enable high-quality anisoplanatic imaging and beam control through the atmosphere over an extended field of view using a phased laser array. The system projects laser energy onto specific locations of extended objects in various geometries, overcomes atmospheric anisoplanatism and backscatter; estimates phase across the full aperture, and reconstructs the target object in great detail to enable high-resolution aimpoint selection and maintenance. Aimpoint maintenance is performed by sequentially analyzing a passive image and a laser spot in rapid succession, in each subaperture at high signal-to-noise ratio. As a further improvement, backscatter issues from the projected laser beam are eliminated by cycling the laser and/or sequentially lasing on different wavelengths within the laser gain bandwidth.

Abstract: Systems and methods that combine forward-model image reconstruction techniques with tomographic estimation of three-dimensional atmospheric turbulence to enable high-quality anisoplanatic imaging and beam control through the atmosphere over an extended field of view using a phased laser array. The system projects laser energy onto specific locations of extended objects in various geometries, overcomes atmospheric anisoplanatism and backscatter; estimates phase across the full aperture, and reconstructs the target object in great detail to enable high-resolution aimpoint selection and maintenance. Aimpoint maintenance is performed by sequentially analyzing a passive image and a laser spot in rapid succession, in each subaperture at high signal-to-noise ratio. As a further improvement, backscatter issues from the projected laser beam are eliminated by cycling the laser and/or sequentially lasing on different wavelengths within the laser gain bandwidth.

Abstract: Systems and methods which combine standard image reconstruction and beam-control techniques with tomographic estimation of three-dimensional atmospheric turbulence to enable high-quality anisoplanatic imaging of distant objects at long range through the atmosphere over an extended field-of-view using a large aperture. More specifically, the systems and methods combine the concepts of atmospheric tomography, forward-model image reconstruction and tip, tilt, beam-walk, and focus control techniques to produce image reconstructions of high quality for large objects that move rapidly as viewed by large apertures in weak or strong extended atmospheric turbulence.

Abstract: A large fiber optic switch system with a free-space optical interconnection configuration. The switch system comprises a plurality of individual switch units, each individual switch unit having a plurality of electronic multi-switch switches each multi-switch switch being re-configurable upon command of a computer processor and having a plurality of electronic input ports and electronics output ports. A first portion of these input ports and a first portion of these output ports are connected directly or indirectly to incoming and outgoing communication lines. A second portion of the output ports is connected to an electronic driver unit that drives an optical emitter array. Each emitter in the emitter array produces a light beam for carrying an optical communication signal.

Abstract: A switch device and method is disclosed that is capable of switching wavelength division multiplexed optical signals. The device comprises a switch element that includes a two-dimensional micro-electromechanical mirror. The two-dimensional micro-electromechanical mirror is adapted to reflect an optical signal so that it is directed to a selected target. The switch element may also comprise a beam splitter and a plurality of wave plates. The beam splitter is adapted to transmit light in one polarization and reflect light in another polarization. The wave plates are adapted to change the polarization of the light so that the beam splitter either reflects or transmits the light.

Abstract: A large fiber optic switch system with a free-space optical interconnection configuration. The switch system comprises a plurality of individual switch units, each individual switch unit having a plurality of electronic multi-switch switches each multi-switch switch being re-configurable upon command of a computer processor and having a plurality of electronic input ports and electronics output ports. A first portion of these input ports and a first portion of these output ports are connected directly or indirectly to incoming and outgoing communication lines. A second portion of the output ports is connected to an electronic driver unit that drives an optical emitter array. Each emitter in the emitter array produces a light beam for carrying an optical communication signal.

Abstract: A switch device and method is disclosed that is capable of switching wavelength division multiplexed optical signals. The device comprises a switch element, which may include a detector, an emitter array, and a switch controller. The detector is adapted to detect optical signals and is positioned to receive light from a source. The emitter array is positioned to transmit light to a plurality of targets. The emitter comprises a plurality of emitters, each emitter being adapted to generate light signals. The light signals generated by each emitter are transmitted to at least one predetermined target. The switch controller is in communication with the detector and the emitter array. The switch controller is adapted to cause the emitter array to generate the detected signal. The switch elements are grouped in an array and dichroic beam splitters may be used to reflect predetermined ranges of wavelengths to the individual switch elements.

Abstract: A method and system is disclosed for switching signals between at least one optical fiber and a plurality of nodes through free space. The invention includes a switch that comprises at least one switch element. The switch element can detect signals transmitted by the optical fiber, at least one node, or both. The switch element can also transmit signals to the optical fiber, at least one node, or both. A mirror is provided for reflecting signals to and from the nodes through free space. An imaging telescope may also be provided for imaging light on to the mirror from the switch element.

Abstract: This invention enables a plurality of switch elements, each capable of receiving and transmitting a specific wavelength of light, to exchange information and to multiplex temporally-encoded information in time from two or more of the local processors. The process is accomplished by the use of an intermediate plane that has one or more ports that can detect light over a broad band of wavelengths, and that can transmit light at one or more specific wavelengths back to the local processors. The ports may be used to transmit time multiplexed and/or wavelength multiplexed signals.

Abstract: An optical switching system, device, and method are disclosed that are capable of providing high throughput optical signal switching. Bandpass filters are provided for narrow-band demultiplexing of an optical signal to a plurality of switching elements. The system includes a demultiplexing device for wide-band wavelength demultiplexing to a plurality of optical switching devices.

Abstract: A method and system is disclosed for switching signals between at least one optical fiber and a plurality of nodes through free space. The invention includes a switch that comprises at least one switch element. The switch element can detect signals transmitted by the optical fiber, at least one node, or both. The switch element can also transmit signals to the optical fiber, at least one node, or both. A mirror is provided for reflecting signals to and from the nodes through free space. An imaging telescope may also be provided for imaging light on to the mirror from the switch element.

Abstract: A switch device and method is disclosed that is capable of switching wavelength division multiplexed optical signals. The device comprises a switch element that includes a two-dimensional micro-electromechanical mirror. The two-dimensional micro-electromechanical mirror is adapted to reflect an optical signal so that it is directed to a selected target. The switch element may also comprise a beam splitter and a plurality of wave plates. The beam splitter is adapted to transmit light in one polarization and reflect light in another polarization. The wave plates are adapted to change the polarization of the light so that the beam splitter either reflects or transmits the light.

Abstract: An optical switching system, device, and method are disclosed that are capable of providing high throughput optical signal switching. Bandpass filters are provided for narrow-band demultiplexing of an optical signal to a plurality of switching elements. The system includes a demultiplexing device for wide-band wavelength demultiplexing to a plurality of optical switching devices.

Abstract: This invention enables a plurality of switch elements, each capable of receiving and transmitting a specific wavelength of light, to exchange information and to multiplex temporally-encoded information in time from two or more of the local processors. The process is accomplished by the use of an intermediate plane that has one or more ports that can detect light over a broad band of wavelengths, and that can transmit light at one or more specific wavelengths back to the local processors. The ports may be used to transmit time multiplexed and/or wavelength multiplexed signals.

Abstract: A switch device and method is disclosed that is capable of switching wavelength division multiplexed optical signals. The optical switch device includes sources, targets, switching elements, and gratings. The source transmits an optical signal and the targets receive the optical signal. Each switch element includes a detector array, an emitter array, and a switch controller. The detector receives light from the source. The emitter array has emitters that transmit light to the targets. The switch controller is in communication with the detector and the emitter array. The switch controller causes the emitter array to generate the detected signal. A grating is positioned between the source and the switch elements. The grating disperses the optical signal into sets of wavelengths. The switch elements are positioned to receive differing sets of wavelengths and to transmit sets of wavelengths in an imaging configuration with the sources or targets.

Abstract: A switch device and method is disclosed that is capable of switching wavelength division multiplexed optical signals. The device comprises a switch element, which may include a detector, an emitter array, and a switch controller. The detector is adapted to detect optical signals and is positioned to receive light from a source. The emitter array is positioned to transmit light to a plurality of targets. The emitter comprises at least one emitter and a modulator array. The modulator array selectively allows light to pass through the modulator array. The switch controller is in communication with the detector and the emitter array. The switch controller is adapted to cause the emitter array to generate the detected signal. The switch elements are grouped in an array and dichroic beam splitters may be used to reflect predetermined ranges of wavelengths to the individual switch elements.

Abstract: A switch device and method is disclosed that is capable of switching wavelength division multiplexed optical signals. The device comprises a switch element that may include a beam splitter, a plurality of wave plates, and a plurality of micro-electromechanical mirrors. The beam splitter is adapted to transmit light in one polarization and reflect light another polarization. The wave plates are adapted to change the polarization of the light so that the beam splitter either reflects or transmits the light. The micro-electromechanical mirrors are adapted to position the beam of light so that it is directed to a selected target.

Abstract: A photon-counting spatial light modulator that has an avalanche photodiode structure and is designed to operate in Geiger mode is sensitive to a single photon of light. An avalanche photodiode having an applied electric field is excited by an optical wave comprising one or more photons whose energies exceed the band-gap energy of the photodiode material. This localized electrical excitation alters the refractive index of the material through various effects, most notably the transient thermo-optic effect and the photorefractive effect. A second optical wave is incident during or shortly after the electrical excitation, and comprises photons whose energy is less than or nearly equal to the band-gap energy. This second optical wave is then used to read out the avalanche-induced variation in refractive index.

Abstract: The passive wind profilometer measures wind transverse to a line of sight as a function of range. Schlieren which are natural occurrences in wind act as refracting lenses which move along with the wind. The patches of refracted light are detected by use of a light-intensity-sensitive television. camera and a microprocessor. The range of the schlieren are determined from the scale size of the refracted patches of light. The microprocessor, using a specific algorithm for processing the light intensity data, then statistically compares the positions of the schlieren at different times to determine the wind velocity.

Abstract: A filtering apparatus 30 passes an incident beam of light through a first lens having a first focal length, causing the incident beam of light 32 to be focussed, and then passes the incident beam of light through a pinhole 36 having an opening of a predetermined size. In accordance with one aspect of the invention, the pinhole 36 is spaced from the first lens 34 by a distance which is greater than, or less than, but not equal to the lens' focal length wherein only a portion of the incident beam of light passes through the opening of the pinhole 36. In the illustrated embodiment, the pinhole 36 has a size which is significantly larger than the nominal diffraction limited spot size of the first lens 34. The incident beam of light which passes through the pinhole is then directed toward a second lens 38 having a second focal length. In a preferred embodiment, the second lens 38 is spaced from the pinhole 36 by a distance substantially equal to the second lens' focal length.