Abstract: A laser warning receiver system and method having at least four optical components mapped to a photodetector array to provide for omnidirectional detection of incident laser light. In some cases, a fifth optical component is mapped to the central portion of a photodetector array to provide hemispheric detection of laser light. The laser warning receiver system is configured to detect laser light in the NIR, SWIR, MWIR, and/or LWIR range using a single photodetector array and ROIC.

Abstract: A spectral feature of a pulsed light beam produced by an optical source is adjusted by receiving an instruction to change a spectral feature of the pulsed light beam from a value in a first target range to a value in a second target range; regulating a first operating characteristic of the optical source; determining an adjustment to a second actuatable apparatus of the optical source; and adjusting the second actuatable apparatus by an amount based on the determined adjustment. The first operating characteristic is regulated by adjusting a first actuatable apparatus of the optical source until it is determined that the first operating characteristic is within an acceptable range of values. The adjustment to the second actuatable apparatus is determined based at least in part on: a relationship between the adjustment of the first actuatable apparatus and a spectral feature of the light beam, and the second target range.

Abstract: Fiber amplifier and/or mode filter including a linearly birefringent LMA fiber coiled at a radius of curvature over a bend length to differentiate a fundamental optical mode from supported higher-order modes through bending losses. The LMA fiber may be a polarization-maintaining (PM) fiber having a variety of geometrical core shapes and cladding configurations. In some embodiments, the birefringent LMA fiber includes a radially asymmetric core that is angularly rotated over a length of the coiled fiber to ensure bending losses are experienced in orthogonally oriented higher-order modes associated with some orientation relative to the core orientation. In some embodiments, the fiber coiling is two-dimensional with bending occurring only about one axis. In some embodiments, an asymmetric core is pre-spun to a predetermined axial spin profile. In some embodiments, angular rotation of the core is achieved through mechanically twisting an un-spun fiber over a length of the coil.

Abstract: The present invention relates to an optical fiber which can improve OSNR in an optical transmission system in which Raman amplification and an EDFA are combined. With respect to the optical fiber, a predetermined conditional formula is satisfied by an effective area Aeff1450 [?m2] at a wavelength of 1450 nm, a transmission loss ?1450 [/km] at a wavelength of 1450 nm, and a transmission loss ?1550_dB [dB/km] at a wavelength of 1550 nm. Further, with respect to the optical fiber, another predetermined conditional formula is satisfied by an effective area Aeff1550 [?m2] at a wavelength of 1550 nm, and a transmission loss ?1550 [/km] at a wavelength of 1550 nm.

Abstract: An array of optical amplifiers that recycles the unused pump power of some or all constituent amplifiers thereof, thereby beneficially improving pump-power utilization therein compared to that of conventional optical amplifiers. In an example embodiment, different amplifiers of the array can be configured to receive approximately equal pump power and be used to independently amplify different respective optical signals. In various embodiments, the unused pump power can be recycled using one or more optical couplers and/or optical paths that appropriately interconnect different amplifiers of the array. Some embodiments have one or more optical loops configured to operate as a ring laser that regenerates pump light in response to the unused pump power being coupled thereto. Some embodiments provide a spectral gain profile suitable for amplifying WDM signals in at least some of the constituent amplifiers of the array.

Abstract: Position reference system and method for positioning and tracking one or more objects which in addition to range and azimuth also provides the elevation angle of the target relative to the instrument axes of the sensor platform. The system and method is based on a near IR laser radar transceiver and one or more active or passive retroreflectors placed on the objects to be positioned. The present invention further includes an internal beam stabilization mechanism protected from the environment and utilize a cylindrical window which is transparent for the near IR laser radiation, but absorbs all visible and UV radiation and thus protects the optical parts from ambient solar radiation. In addition, the cylindrical window protects all internal mechanical parts, notably the rotating and moving parts, from a corrosive and freezing/icing environment.

Abstract: Described herein are methods and subsystems for use with a timing generator having an output driver at which a timing signal having timing pulses is output. A method includes controlling the timing generator to cause the output driver to output a timing signal having an expected duty cycle, and filtering the timing signal to produce a DC voltage having a magnitude indicative of an actual duty cycle of the timing signal. The method also includes converting the DC voltage to a digital value indicative of the actual duty cycle of the timing signal. The method can also include comparing the digital value to an expected value corresponding to the expected duty cycle, and using results of the comparing to determine an error associated with the timing generator and/or produce a calibration table that can be used to calibrate the timing generator and/or calibrate a measurement made using the timing generator.

Abstract: A system includes a laser system having a master oscillator and a planar waveguide (PWG) amplifier having one or more laser diode pump arrays, a PWG pumphead, input optics, and output optics. The PWG pumphead is configured to receive a low-power optical beam from the master oscillator and generate a high-power optical beam. The PWG pumphead includes a laser gain medium, a cartridge, and a pumphead housing. The cartridge is configured to receive and retain the laser gain medium, and the cartridge includes one or more cooling channels configured to transport coolant in order to cool the laser gain medium. The pumphead housing is configured to receive and retain the cartridge, where the cartridge is removable from the housing.

Abstract: An optical amplifying element includes: a pair of reflectors that constitutes a cavity; an active layer disposed between the pair of reflectors; and an excitation unit configured to excite the active layer, wherein the active layer excited by the excitation unit amplifies intensity of a laser beam that enters the optical amplifying element when the laser beam reflects back and forth within the cavity, and wherein the pair of reflectors is configured to change a length of the cavity according to a wavelength of the laser beam.

Abstract: A beam reverser module for an optical power amplifier of a laser arrangement comprises at least one reflecting surface for receiving an incoming laser beam propagating in a first direction and reflecting the incoming laser beam into a second direction different from the first direction, wherein the at least one reflecting surface is a highly reflecting surface of at least one mirror.

Abstract: The present invention provides a method and apparatus for fabricating a grating on a silicon substrate, and the resulting grating device. In some embodiments, the apparatus method includes providing a silicon substrate; growing a diamond layer on the substrate; removing most of the silicon substrate and polishing an obverse face of the silicon to leave a very thin layer of polished silicon on the diamond layer; depositing a stack on the diamond layer, wherein the stack includes a plurality of pairs of dielectric layers on the thin layer of polished silicon, wherein each pair of the plurality of pairs of dielectric layers includes a first layer having a first index of refraction value and a second layer having a second index of refraction value that is different than the first index of refraction value; and forming a diffraction grating on an outer surface of the stack.

Abstract: An optoelectronic signal translating device having a region containing rare earth or transition metal ions for generation of radiation of a predetermined wavelength. Said region includes an organic complex comprising a ligand adapted to enhance the emission of radiation and a chromophore separately co-operable with a radiation source of wavelength not greater than that of said predetermined desired radiation. Said chromophore can be excited to cross-couple with the upper permitted energy state of said rare earth or transition metal ions, thereby generating said predetermined desired radiation by subsequent decay of said ions to the permitted lower energy state.

Abstract: An electronic apparatus includes a light source that outputs a laser light; a scanning unit that scans the laser light; a reflective member having a reflective surface that reflects the laser light; a light-receiving unit that receives a first reflected light reflected by the reflective member; and a signal processing unit that calculates a distance from the light source to the reflective surface using the first reflected light and determines a direction in which the laser light is output using the distance.

Abstract: In one aspect, the present disclosure describes a fiber laser system for the generation and delivery of femtosecond (fs) pulses in multiple wavelength ranges. For improved versatility in multi-photon microscopy, an example of a dual wavelength fiber system based on Nd fiber source providing gain at 920 and 1060 nm is described. An example of a three-wavelength system is included providing outputs at 780 nm, 940 nm, and 1050 nm. The systems include dispersion compensation so that high quality fs pulses are provided for applications in microscopy, for example in multiphoton microscope (MPM) systems.

Abstract: The present invention is directed to an apparatus and method for bistatic laser range imaging. The apparatus utilizes two light sources, two receivers, a demodulator and an image processor such that a three dimensional image is produced. The method includes generating beams of intensity modulated light, one toward a target, another toward a receiver. The light toward the target reflects from the target toward another receiver. The modulation envelopes of the beams of light are demodulated into components, the components digitized, then decimated, and a three dimensional image is constructed from the digitized components.

Abstract: An optical module providing a semiconductor optical amplifier (SOA), and a process to assembly the optical module are disclosed. The optical module provides front and rear coupling units each optically coupled with the SOA and fixed to the housing enclosing the SOA. The housing has a slim wall fixing a lens holder soldered to the slim wall. The front and/or rear coupling unit is fixed to the lens holder by YAG laser welding after the active alignment by using a spontaneous emission of the SOA, and amplified emission of externally provided test beam.

Abstract: An object is to provide an optical device capable of relaxing a manufacturing condition for an optical waveguide used in the optical device. An optical device 500 is provided with an optical waveguide 200 including a core and a cladding optically joined together, and a temperature controller 600 that controls temperature of the optical waveguide, wherein the optical waveguide includes the core and the cladding formed such that a normalized frequency specified for light propagating through the optical waveguide changes across a cutoff frequency of a guided mode determined from a structure of the optical waveguide in a temperature range in which a refractive index of the core is higher than a refractive index of the clad. The temperature controller controls the temperature of the optical waveguide over a temperature range across temperature at which the normalized frequency equals to the cutoff frequency.

Abstract: Methods and apparatuses for determining the polarization state and for providing polarization control in optical fiber lasers and amplifiers. One embodiment of the invention is an optical fiber amplifying system including a circulator (260) having a first optical port (260a), a second optical port (260b) that is configured to output radiation received from the first optical port, and a third optical port (260c) that is configured to output radiation received from the second optical port; one or more amplifier stages (216) connected in series, together having an optical input (216a) optically coupled to the second port of the circulator, and an optical output (216b); and a polarization detector (240) having an optical input optically coupled to the third port of the circulator. Thereby the polarization state of the amplified radiation can be determined using radiation backscattered from the amplifying stage.

Abstract: The present invention relates generally to high brightness optical fiber systems and, more particularly to optical fiber systems 104 having an optical power module 151 remote from an initial amplifier stage 101. In one aspect of the invention, the optical fiber system comprises a first active optical fiber 102 operatively coupled to one or more first pump sources 104; a first signal optical fiber 110 coupled to the first active optical fiber 102; one or more final pump sources 120; one or more final pump optical fibers 130, coupled to one or more of the final pump sources 120; and spatially separated from the one or more final pump sources 120 and the initial amplifier stage 101 comprising the first active optical fiber 102, a power module 151, comprising a final active optical fiber 150, coupled to the first signal optical fiber 110, said final active optical fiber 150 being coupled to said one or more final pump optical fibers 130.

Abstract: The present disclosure provides an optical amplifier using an optical fiber. The optical fiber includes a single-mode optical fiber in which a plurality of rare earth elements is doped simultaneously; first and second optical fiber gratings disposed at opposite sides of the optical fiber, respectively, and totally reflecting light having a wavelength in a specific range; a pumping light source configured to generate a pumping light to excite rare earth ions in the optical fiber; and an optical coupler connected to the optical fiber and configured to transmit a light signal generated from a light source and the pumping light generated from the pumping light source to the optical fiber. Therefore, it is possible to obtain efficient amplification of a light signal through a simple configuration using the rare earth elements-doped optical fiber.