Abstract: An apparatus includes a photonic integrated circuit, which includes at least one splitter configured to split at least one input beam into multiple input beamlets and multiple phase modulators configured to phase-shift at least some of the input beamlets. The apparatus also includes an array of optical amplifiers configured to amplify the phase-shifted input beamlets and generate amplified beamlets. The apparatus further incudes a beam combiner configured to combine the amplified beamlets and generate an output beam. In addition, the apparatus includes a controller configured to control the phase modulators in order to adjust phasing of the phase-shifted input beamlets.

Abstract: A pulsed fiber laser amplifier system including a plurality of optical seed beam sources each generating a seed pulse beam at a different point in time and at a different wavelength than the other seed beam sources. The system further includes an optical coupler responsive to each of the seed pulse beams that outputs the pulse beams on a common optical path as a pulsed envelope beam. The system also includes a plurality of fiber amplifier stages responsive to the pulse envelope beam from the optical coupler that amplifies each pulse in the pulse envelope beam. The system further includes a spectral-temporal beam combiner that provides a separate delay for each of the amplified pulses in the pulse envelope beam so as to output a single output beam pulse that is in overlap of all of the individual amplified pulses in the pulse envelope beam.

Abstract: A pulsed fiber laser amplifier system including a plurality of optical seed beam sources each generating a seed pulse beam at a different point in time and at a different wavelength than the other seed beam sources. The system further includes an optical coupler responsive to each of the seed pulse beams that outputs the pulse beams on a common optical path as a pulsed envelope beam. The system also includes a plurality of fiber amplifier stages responsive to the pulse envelope beam from the optical coupler that amplifies each pulse in the pulse envelope beam. The system further includes a spectral-temporal beam combiner that provides a separate delay for each of the amplified pulses in the pulse envelope beam so as to output a single output beam pulse that is in overlap of all of the individual amplified pulses in the pulse envelope beam.

Abstract: A method of spectral beam combining comprising the steps of projecting a plurality of laser beamlets of different wavelengths onto a first spectrally dispersive element, spatially chirping the plurality of beamlets via the first spectrally dispersive element, rearranging the spatially chirped beamlets with a beam redirecting element, and combining the beamlets into a single output beam via a second spectrally dispersive element.

Abstract: A pulsed fiber array laser system that has actively stabilized coherent beam combination (CBC) is disclosed. The active stabilization is accomplished using both piston phase control and intra-pulse phase control, allowing a much greater increase in pulse energy. Further stabilization using intra-pulse amplitude control is also disclosed. A chirp profile can be written on the output pulse to enable specific applications. An amplitude profile of the amplifier array may optionally be tailored to match to a reference electrical pulse. Using the current invention, a much smaller number of amplifier chains will be needed to achieve certain pulse energy, resulting in a system with lower complexity, lower cost, smaller size, less weight, and higher reliability.

Abstract: A pulsed fiber array laser system that has actively stabilized coherent beam combination (CBC) is disclosed. The active stabilization is accomplished using both piston phase control and intra-pulse phase control, allowing a much greater increase in pulse energy. Further stabilization using intra-pulse amplitude control is also disclosed. A chirp profile can be written on the output pulse to enable specific applications. An amplitude profile of the amplifier array may optionally be tailored to match to a reference electrical pulse. Using the current invention, a much smaller number of amplifier chains will be needed to achieve certain pulse energy, resulting in a system with lower complexity, lower cost, smaller size, less weight, and higher reliability.

Abstract: A method of spectral beam combining comprising the steps of projecting a plurality of laser beamlets of different wavelengths onto a first spectrally dispersive element, spatially chirping the plurality of beamlets via the first spectrally dispersive element, rearranging the spatially chirped beamlets with a beam redirecting element, and combining the beamlets into a single output beam via a second spectrally dispersive element.

Abstract: An electrically controlled variable reflectance mirror that includes a Pockels cell which enables its retardation or birefringence to be controlled in order to vary the light outcoupled from a laser cavity. Since the retardation is a function of the voltage applied to the Pockels cell, the voltage can be used to control the fraction of the output beam that is outcoupled from the laser cavity. The Pockels cell is formed with a constant reflectivity profile to form an electrically controlled uniform reflectivity electro-optic mirror. In an alternate embodiment of the invention, the Pockels cell is configured with spatially varying retardation to form an electrically controlled graded reflectivity electro-optic mirror. Both embodiments of the invention enable a lasing system, such as a solid state lasing system, to be operated over a relatively wide range of operating parameters utilizing a single set of optics.

Abstract: An optical communication system for communicating through a turbulent medium is disclosed. It includes an optical transmitter and an optical receiver. The optical receiver receives an optical signal containing information that fluctuates as it passes through a turbulent medium. It comprises a reflector for collecting the optical signal and for focusing it, a probe laser for generating an optical probe beam, an optical device having an OTM responsive to the focused optical signal and the probe beam and operative to change a characteristic of the probe beam, and optoelectronic detector means responsive to the changed characteristic and, operative to develop an output electrical signal representative of the information contained in the received optical signal.

Abstract: An optical collimator system for a high power fiber laser system that collimates the individual light beams amplified by a plurality of fibers in the laser system. The fibers are optically coupled to undoped fibers and the fibers are optically coupled to one surface of an optical substrate. A registration guide precisely aligns the fibers to the substrate. Lenses are optically coupled to an opposing surface of the substrate in precise alignment with the optical fibers. The light beam from each fiber propagates through the substrate and diverges, and the associated lens collimates the beam to have a desired beam width and direction. Each lens includes an anti-reflective coating so that the optical beam from the fiber is not significantly reflected back through the substrate.

Abstract: An electro-optic interconnect for use with optical signals and a probe beam is disclosed. A plurality of first optoelectronic detectors responds to an optical signal and develops a plurality of first electrical signals. A probe laser generates the probe beam. Means are responsive to the plurality of first electrical signals and changes a characteristic of the optical probe beam. A second optoelectronic detector responds to the changed characteristic and develops an output electrical signal representative of the optical signals. Alternatively, the second optoelectronic detector can be eliminated and direct optical signal processing can be implemented. In another aspect, a time compensation network serves to synchronize the probe and the signal beams. The electro-optic interconnect can be configured to add and subtract the optical signals.

Abstract: An optoelectronic communication system for use with an optical signal that passes through a turbulent environment is disclosed. The communication system comprises an optical transmitter for transmitting an optical signal, and an optoelectronic receiver. The optoelectronic receiver comprises a reflector for collecting the optical signal and for propagating a plurality of portions of it. A plurality of first optoelectronic detectors responds to a selected portion of the optical signal and each develops a plurality of first electrical signals. A probe laser generates an optical probe beam. Means are responsive to the plurality of first electrical signals and changes a characteristic of the optical probe beam corresponding to the information. A second optoelectronic detector responds to the changed characteristic and develops an output electrical signal representative of the information contained in the received optical signal.

Abstract: A time compensation architecture for use with a plurality of optical signals is disclosed. It comprises means for receiving the plurality of optical signals, optical means for selectively delaying the propagation of each of the plurality of optical signals, and means for outputting the time delayed optical signals. The delay may be achieved by changing the indices of refraction or the material lengths of the elements and can either be an active or a passive compensation technique.

Abstract: An apparatus is provided including a source of spectrally dispersed seed wavelengths optically coupled to an array of fibers. Laser diode pumps are optically coupled to the array of fibers for amplifying the wavelengths through the array. A computer controlled feedback loop intercouples the array of fibers and laser diode pumps, the source of seed wavelengths and/or phase modulators for maintaining the wavelengths and relative phases in the array of fibers to desired levels. A compressor is optically coupled to an end of the array of fibers so as to receive and overlap the wavelengths from the individual fibers of the array.

Abstract: An optical interconnect for use with a probe beam and optical signals is disclosed. The interconnect comprises an optical waveguide for propagating the probe beam, an optical transcription material that changes a characteristic of the probe beam at locations where the optical signals interact with the probe beam. A signal processor develops an output signal from the changed characteristic representative of the information contained in the optical signals. The optical signals may be amplitude or phase modulated or polarized. The interconnect can be configured to add and subtract the optical signals.

Abstract: An apparatus is provided including a source of spectrally dispersed seed wavelengths optically coupled to an array of fibers. Laser diode pumps are optically coupled to the array of fibers for amplifying the wavelengths through the array. A computer controlled feedback loop intercouples the array of fibers and laser diode pumps, the source of seed wavelengths and/or phase modulators for maintaining the wavelengths and relative phases in the array of fibers to desired levels. A compressor is optically coupled to an end of the array of fibers so as to receive and overlap the wavelengths from the individual fibers of the array.

Abstract: An optical amplifier (20, 100) includes an elongated slab (22, 102) of solid state lapsing material, such as a rare earth doped yttrium-aluminum-garnet (YAG) slab. In order to provide a relatively increased absorption length and thus a higher overall efficiency, the optical amplifier (20, 100) in accordance with the present invention incorporates end pumping in which the pumped light is coaligned with the amplified light resulting in relatively longer absorption lengths and higher overall efficiencies. The coaligned pumped sources are directed to lateral faces of the slab (22, 102) which include footprints (41, 43, 108) or windows. In order to cause internal reflection of the pump beam along the lapsing axis, the end faces (28, 30, 110) are formed at about a 45° angle relative to the longitudinal axis which causes the pumped light to be reflected within the slab co-axially with amplified light.

Abstract: An optical amplifier for use with a solid state laser which includes a pair of elongated slabs of a solid state lasing material, such as a rare earth doped yttrium-aluminum-garnet (YAG) crystal. Two embodiments of the invention are disclosed. In both embodiments of the invention, each of the elongated slabs is formed with a square or generally rectangular cross-section. The slabs are configured such that the longitudinal axes of the slabs are generally co-axial aligned and the slabs are orientated such that the major axis of the slabs are generally orthogonal. By configuring the two slabs to be orthogonal with respect to one another, the integrated thermal lens becomes azimuthally symmetric and can be compensated by a simple external lens. In addition, the negative lensing affect along the major axis of one slab is used to compensate for the positive lensing affect along the minor axis of the other slab and vice versa, thus minimizing the affects of the astigmatism.

Abstract: A solid state saturable absorber (SSSA) is formed from a slab of solid state material, such as Cr.sup.4+ : YAG. Optical distortion caused by the absorption process can be minimized by confining absorption to portions of the solid state slab which can be cooled efficiently. In accordance with an important aspect of the invention, the use of the SSSA in accordance with the present invention allows the repetition rate, pulse width, and energy level of the laser output pulses to be controlled by way of optical pump sources, such as a diode array. The solid state slab material allows for zig-zag propagation and thus, averaging of the thermal gradients caused by absorption, optical pumping and cooling which results in relatively low thermal lensing with virtually no birefringence and therefore allows for passive Q-switching applications in relatively high brightness laser systems.