Abstract: An optical isolator includes a Faraday rotator including a trivalent ion exchange TAG (terbium-aluminum garnet), and arranged around the Faraday rotator, a central hollow magnet and a first and a second hollow magnet units arranged to sandwich the central hollow magnet in an optical axis direction. A magnetic flux density B [T] in the Faraday rotator and an optical path length L [mm] where the Faraday rotator is arranged satisfy 0<B??(1) and 14.0?L?24.0??(2). The optical isolator, compared with a conventional Faraday rotator such as a terbium-gallium garnet (TGG) crystal, contributes to reduction of a thermal lensing effect, being a pending problem, in a high-output fiber laser.

Abstract: Disclosed herein are a system, non-transitory computer readable medium, and method for monitoring and replaying packets. A network tap forwards packets from a first network to a second network. At least one node in the first network has the same IP address as a node in the second network. The packets are replayed in the second network.

Abstract: An optical isolator for use with high power, collimated laser radiation includes an input polarizing optical element, at least one Faraday optical element, at least two reflective optical elements for reflecting laser radiation to provide an even number of passes through said at least one Faraday optical element, at least one reciprocal polarization altering optical element, an output polarizing optical element, at least one light redirecting element for remotely dissipating isolated or lost laser radiation. The isolator also includes at least one magnetic structure capable of generating a uniform magnetic field within the Faraday optical element which is aligned to the path of the collimated laser radiation and a mechanical structure for holding said optical elements to provide thermal gradients that are aligned to the path of the collimated laser radiation and that provide thermal and mechanical isolation between the magnetic structure and the optical elements.

Abstract: Disclosed herein are a system, non-transitory computer readable medium, and method for monitoring and replaying packets. A network tap forwards packets from a first network to a second network. At least one node in the first network has the same IP address as a node in the second network. The packets are replayed in the second network.

Abstract: An optical isolator includes: an optical isolator chip in which a first polarizer, a Faraday rotator made of a ferromagnet, and a second polarizer are bonded and fixed in this order; and a magnet for applying a magnetic field to the optical isolator chip. A light-entering end surface or a light-exiting end surface of the optical isolator chip is bonded and fixed to a component. On an optical axis of the optical isolator, a center of a magnetic flux formed by the magnet is positioned closer to the end surface side bonded and fixed to the component than a central position of the Faraday rotator on the optical axis. The optical isolator has high bonding reliability to the component.

Abstract: A modulator assembly for modulating light comprising a first and a second electro-absorption modulator which each at least substantially only act on a polarization component of incident light; a light generating assembly for generating light which includes a first and a second polarization component; a first electro-absorption modulator for modulating the light generated by the light generating assembly, wherein the first electro-absorption modulator at least substantially only modulates the first polarization component of the light, so that the light exiting from the first electro-absorption modulator includes a modulated and an unmodulated polarization component; a polarization converter for changing the polarization direction of the light exiting from the first electro-absorption modulator.

Abstract: The invention relates to an optical security system comprising an optical element with a patterned anisotropic optical property, wherein information is encoded and encrypted in the pattern of the optical element. The system further comprises a patterned polarizer in which the pattern is such that the information stored in the optical element can be decrypted.

Abstract: A multi-surface image acquisition system includes a multi-surface observation prism which includes one or more prisms and has a light path formed to collect surfaces in respective directions to be observed of a subject having a three-dimensional structure into one direction, in which a light path length is corrected by utilizing a difference in refractive index between glass and air to equalize a working distance of each surface. A light field camera expands a focal-depth adjustment range for two or more images focused on same plane through the prism. A three-dimensional subject can be observed in multiple directions at the same time, including an observation of cells.

Abstract: A packaged integrated white light source configured for illumination and communication or sensing comprises one or more laser diode devices. An output facet configured on the laser diode device outputs a laser beam of first electromagnetic radiation with a first peak wavelength. The first wavelength from the laser diode provides at least a first carrier channel for a data or sensing signal.

Abstract: An anti-counterfeit medium includes a portion having optical transparency, a retardation layer facing the portion and including regions whose slow axis directions are different from each other, and a polarizing layer facing the retardation layer at a position of the portion. The anti-counterfeit medium includes only the polarizing layer as a polarizer. A portion out of the anti-counterfeit medium where the portion, the retardation layer, and the polarizing layer form a stacked structure has optical transparency.

Abstract: An optical device includes: a plurality of optical components arranged along a first direction, each optical component having an optical surface, a first surface intersecting with the optical surface, and a second surface intersecting with the optical surface and the first surface; and a base member that integrally holds the plurality of the optical components and has a first holding surface and a second holding surface, the first holding surface holding the optical components and fixing positions of the optical components in a second direction intersecting with the first direction in a state of being in contact with the optical components on the first surface, the second holding surface holding the second surface of the optical components with an adhesive interposed therebetween and fixing positions of the optical components in a third direction intersecting with the first direction and the second direction.

Abstract: An optical transmission connector device includes: a transmission-side connector sending optical signals; and a reception-side connector receiving the optical signals sent from the transmission-side connector. The transmission-side and the reception-side connectors have: optical fibers transmitting optical signals; and optical members disposed in contact with or in the vicinity of one end surfaces of the optical fibers. The optical member of the transmission-side connector is formed so as to convert the optical signals emitted from the one end surfaces of the optical fibers into approximately parallel beams of light and so as to cause the centers of light beams of the approximately parallel beams of light to intersect at approximately one point. The optical member of the reception-side connector is formed so as to cause the optical signals converted into the approximately parallel beams of light at the optical member of the transmission-side connector to enter the separate optical fibers.

Abstract: An illumination optical apparatus includes a plurality of birefringent members made of a birefringent material and arranged in an optical path on an incidence side of an optical integrator. The members change a polarization state of illumination light such that first and second rays of the illumination light are polarized in different directions on the pupil plane. The birefringent members are arranged such that an optical path length of the first ray in the birefringent material is different from an optical path length of the second ray in the birefringent material, and are arranged so as to change the polarization state of the illumination light incident on the plurality of the birefringent members in a linear polarization state having a substantially single polarization direction such that each of the first and second rays is polarized in a substantially circumferential direction about the optical axis on the pupil plane.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for optical communications. In one aspect, an optical circulator array includes a plurality of stacked three port circulators each having a respective first port of a first port array, a respective second port of a second port array, and a respective third port of a third port array, wherein each of the plurality of stacked three port circulators share optical components including: a first Wollaston prism coupled to the first port array, a first lens, a first half wave plate, a polarization dependent beam path separator, a second half wave plate, a second lens, a propagation direction dependent polarization rotation assembly, a second Wollaston prism coupled to the second port array, and a third Wollaston prism coupled to the third port array.

Abstract: An optical isolator with a collimator which is used at the tip end of a laser beam transmitting fiber utilized in a laser processing. The optical isolator can provide solutions to the problems how to make return lights to be isolated from an incident light path and how to prevent the light energy from being conducted to an incident fiber, a laser oscillator, the collimator, and the optical isolator. The solutions include light-receiving fibers disposed at focal points of a collimator lens to which reflected lights from a workpiece return through the optical isolator. The return lights are then led to a ceramic tube where the return light energy is converted to thermal energy and dissipated.

Abstract: An optical device comprising a first combination of birefringent prisms with parallel optic axes for dividing an optical input beam into polarized beams, a second combination of birefringent prisms with parallel optic axes for combining polarized beams into an output beam, a polarization changer, and means for improving isolation in optical isolators, attenuators and switches and for improving material costs, light transmission, size and beam capacity in optical isolators, attenuators, switches and circulators.

Abstract: A Faraday rotator includes two magnet sub-assemblies assemblies spaced apart and aligned with each other with a gap therebetween. Each magnet sub-assembly includes a central magnet magnetized in direction parallel to the gap. The central magnet is sandwiched between two end magnets magnetized in a direction perpendicular to the gap. A magneto-optic crystal is located in the gap between the central magnets.

Abstract: A Universal Serial Bus (USB) dongle may include an optical transceiver having a USB interface for engagement to an electronic device such as a laptop computer or other USB-configured device. The USB dongle may include a converter or buffering, isolation, modulation or amplification circuitry. The USB dongle sends and receives data signals which may be carried upon an optical transmission as generated by an LED light source which in turn is in communication with a host device such as a network processor. The USB dongle may also include operational amplifiers (op-amps) and transistor amplifiers.

Abstract: A photonic device comprising a base plate, a photonic laser coupled to the base plate, wherein the photonic laser is configured to generate a light, a lens coupled to the base plate, wherein the lens is configured to receive the light from the photonic laser, form a focused light, and pass the focused light to a reflector, and the reflector incorporated with the base plate such that the lens is positioned between the photonic laser and the reflector, wherein the reflector is configured to receive the focused light, and wherein the reflector is configured to steer a first portion of the focused light through the base plate using total internal reflection.

Abstract: Systems for switching optical signals are disclosed. Such a system may include a splitter and a plurality of polarizing filters. The splitter may be configured to receive emitted light and duplicate the emitted light into a plurality of light copies. Each polarizing filter may have a polarization and may be operably connected to the splitter. In addition, each polarizing filter may be configured to receive at least one of the plurality of light copies, filter the at least one of the plurality of received light copies such that light having a similar polarization as that of the polarizing filter passes through the polarizing filter, and output one of a plurality of outputs.

Abstract: A fiber-based, magneto-optic (MO) optical modulator or switch based on Sagnac interferometry is provided. The system uses a magneto-optic Faraday rotator (MOFR) to produce optical modulation with low magnetic fields. The Sagnac geometry allows for increased modulation at lower fields than traditional MO modulators. This switch uses the MOFR to create different states of polarization in counter-propagating waves, which results in interference at the output port. A magnetic field is used to control the amount of rotation in the state of polarization (SOP), and therefore, the ON-OFF extinction ratio.

Abstract: An optical signal quality monitoring apparatus includes a trajectory length acquirer measuring a Stokes vector of an optical transmission signal over an optical signal modulation frequency band and acquiring the length of a trajectory in the optical signal modulation frequency band traced out on a Poincare sphere by the measured Stokes vector as the measurement value; a DGD acquirer acquiring a DGD value of the optical transmission signal the Stokes vector of which is measured by the trajectory length acquirer; and a quality value estimator estimating a quality value by using the length of the trajectory acquired by the trajectory length acquirer and the DGD value acquired by the DGD acquirer.

Abstract: A window includes a plurality of transparent substrates spaced apart from each other in a thickness direction; a light transmittance-adjusting layer on a surface of at least one transparent substrate of the plurality of transparent substrates and having a thermochromic or thermotropic characteristic; and an air circulator configured to circulate a heat transfer medium in a space between the plurality of transparent substrates for changing a light transmittance of the light transmittance-adjusting layer.

Abstract: A laser apparatus may include: a master oscillator configured to output a pulsed laser beam at a repetition rate; at least one amplifier disposed on a beam path of the pulsed laser beam; at least one optical shutter disposed on the beam path of the pulsed laser beam; and a controller configured to switch the at least one optical shutter.

Abstract: The invention relates to a system for modulating and displaying optical effects, comprising a lighting device (BV) and at least one displaying object (DO) located outside the lighting device, wherein the lighting device (BV) comprises at least one input polarization unit (POE) for influencing polarization, in particular in a location-dependent manner, and at least one modulation unit (OME) for influencing polarization and/or retardance, in particular in a time-dependent and/or location-dependent manner, and wherein the displaying object (DO) comprises at least one object retarder unit (POB) for influencing retardance, in particular in a location-dependent and/or time-dependent manner, the at least one object retarder unit being suitable for reversibly or irreversibly impressing a piece of image information, and an output polarization unit (PE), and wherein the modulated light (Sout) exiting the lighting device (BV) hits the object retarder unit (POB) in order to interact there with the piece of image informat

Abstract: Methods and systems for PMD compensation in an optical communication system are implemented by transmitting multiple optical signals through a common optical conduit to an optical compensator that adjustably rotates the polarization states of the multiple optical signals and transmits the rotated optical signals to an optical receiver. The receiver, upon sensing an excessive error condition, commands the optical compensator to change the polarization state of rotation, which changes the PMD profile of the received optical signals.

Abstract: The device includes two supports and a primary conductive strip. The primary conductive strip includes a neutral surface, a first side, and a second side. The primary conductive strip is connected one of directly and indirectly on the first side to the two supports such that the primary conductive strip is constrained in two dimensions and movable in one dimension. The device also includes a primary distributed feedback fiber laser. The primary distributed feedback fiber laser includes a fiber axis. The primary distributed feedback fiber laser is connected to the primary conductive strip along one of the first side and the second side such that there is a positive distance between the neutral surface of the primary conductive strip and the fiber axis of the primary distributed feedback fiber laser.

Abstract: A Faraday rotator having a magnet member constituted of a first magnet standing magnetized in the direction perpendicular to the optical axis and taken toward the optical axis, a second magnet standing magnetized in the direction perpendicular to the optical axis and taken against the optical axis, and a third magnet disposed between these magnets and standing magnetized in the direction parallel to the optical axis and taken toward the first magnet from the second magnet. A through-hole (hollow spaces) inside which a Faraday element is disposed, is provided through the center of these magnets and, where the length of the first magnet and that of the second magnet in the optical-axis direction are both represented by L2 and the length of the third magnet in the optical-axis direction is represented by L3, the relationship of the following Expression (1) is established: L2/10?L3?L2.

Abstract: A fiber-based, magneto-optic (MO) optical modulator or switch based on Sagnac interferometry is provided. The system uses a magneto-optic Faraday rotator (MOFR) to produce optical modulation with low magnetic fields. The Sagnac geometry allows for increased modulation at lower fields than traditional MO modulators. This switch uses the MOFR to create different states of polarization in counter-propagating waves, which results in interference at the output port. A magnetic field is used to control the amount of rotation in the state of polarization (SOP), and therefore, the ON-OFF extinction ratio.

Abstract: An electric current measurement device includes a housing defining first and second open ends sealed by first and second sealing means, respectively: a first optical fiber received in an aperture in the first sealing means and in optical communication with a first optical lens in the housing; a first polarization filter in the housing in optical communication with the first lens; a magneto-optical rod within the housing in optical communication with the first polarization filter; a second polarization filter in the housing in optical communication with the rod; and a second optical lens in the housing in optical communication with the second polarization filter. The second sealing means has an aperture for receiving a second optical fiber fixed to the second lens. First and second lids, attachable to the first and second housing ends, respectively include apertures for receiving the first and second optical fibers, respectively.

Abstract: A tunable optical filter includes a medium configured to perform polarization rotation on a portion of a linearly polarized signal beam having a frequency within a selected frequency band, wherein the medium is circularly birefringent within the frequency band, and wherein the polarization rotation is achieved based on two-photon-absorption. The medium may include a gaseous substance, a first reference laser beam having a first reference frequency and a right circular polarization state, and a second reference laser beam having a second reference frequency and a left circular polarization state. The medium may also include a gaseous substance, a reference laser beam having a reference frequency and a linear polarization state, and magnetic field.

Abstract: An optical apparatus and methods for operating on a polarization state of a light beam using a compound tri-state non-reciprocal rotator having two Faraday rotators. A first Faraday rotator rotates the polarization state into one of two partially rotated states at angles +?, ??, where ?=22.5°, and the second Faraday rotates the polarization state from one of the partially rotated states into one of three fully rotated states at angles +2?, 0, ?2?. A polarization selection mechanism guides light in the three fully rotated states differently to enable various devices and different modes of operation. For example, the polarization selection mechanism can generate a tri-state output in the form of two distinct output beams corresponding to two of the three fully rotated states, and an overlapping pair of output beams obtained when the compound tri-state non-reciprocal rotator produces the third of the three fully rotated states.

Abstract: A thick film bismuth doped rare earth iron garnet greater than 50 ?m in thickness with a growth-induced uniaxial anisotropy less than zero, such that all the magnetic domains in the film have their magnetization vectors in the plane of the film. A preferred embodiment comprises a film of composition Bi1.13Gd1.36Lu0.51Fe4.55Ga0.45O12. Films with such anisotropy solve the problem of devices and sensors that require a continuously varying Faraday rotation without the effective insertion losses that are inherent to discrete perpendicular domains. A similar effect can be achieved with a film of perpendicular domains by launching the light in the plane of the thick film in a non-waveguiding mode as opposed to the conventional perpendicular direction.

Abstract: Methods and systems for PMD compensation in an optical communication system are implemented by transmitting multiple optical signals through a common optical conduit to an optical compensator that adjustably rotates the polarization states of the multiple optical signals and transmits the rotated optical signals to an optical receiver. The receiver, upon sensing an excessive error condition, commands the optical compensator to change the polarization state of rotation, which changes the PMD profile of the received optical signals.

Abstract: A polarization controller includes a phase retarder having a rotation about an {1,0,0} axis that receives an optical signal from a waveguide structure. At least one nanoelectromechanical dielectric perturber produces ±45° birefringent axes by placing the at least one nanoelectromechanical dielectric perturber at selective positions around the phase retarder to produce dynamic change in the effective index in one of the modes existent in an extraordinary axial direction.

Abstract: A resonator system comprises an optical resonator that supports one or more pairs of nearly degenerate defect states. One or more magnetic domains comprising at least one gyrotropic material in the optical resonator cause magneto-optical coupling between the two states so that the system lacks time-reversal symmetry. In one embodiment, a single magnetic domain is used that dominates induced magneto-optical coupling between the defect states. The above resonator system may be used together with other components such as waveguides to form circulators, add drop filters, switches and memories.

Abstract: The invention relates to a magneto-optical component, such as a variable light attenuator, light modulator or optical switch, having small size, low power consumption and high speed. The magneto-optical component comprises at least one Faraday rotator comprising a magnetic domain A with magnetization in a direction perpendicular to a light incident/exit surface, a magnetic domain B with magnetization in a direction opposite to the magnetization direction of the magnetic domain A, a planar magnetic domain wall as a boundary between the magnetic domain A and the magnetic domain B, and two light transmission regions through which a plurality of light beams comprising identical traveling directions are transmitted respectively and whose distances from the magnetic domain wall are almost equal to each other, and a magnetic field application system for applying a variable magnetic field to the Faraday rotator to make a position of the magnetic domain wall variable.

Abstract: In an optical transceiver of the invention, a magnet-free Faraday rotator is arranged on an optical axis between a light-emitting part and an end face of an optical fiber, and after rotating a plane of polarization of light of a first wavelength output from the light-emitting part, the light is input to a polarization dependent wavelength-separating film as P-polarized light. The polarization dependent wavelength-separating film has a characteristic of passing the P-polarized light of the first wavelength, and reflecting S-polarized light of the first wavelength and light of a second wavelength output from the optical fiber. As a result it is possible to provide a single-core bidirectional optical transceiver that can be shortened in overall length, with a low loss and without affecting transfer characteristics.

Abstract: Methods for optical isolation in high peak power fiber-optic systems prevent damage to a facet within a fiber-optic isolator caused by back-reflected light from, for example, an optical amplifier. Preventing damage to the facet may include expanding a mode area of the back-reflected light and/or reducing a change in refractive index.

Abstract: Provided are a color selective active polarizer controlled by a magnetic field and a magnetic display panel employing the color selective active polarizer. The color selective active polarizer includes a magnetic material layer structured such that magnetic particles are buried in a transparent insulating medium. Dyes or color absorbing particles are mixed in the magnetic material layer. The color selective active polarizer transmits light polarized in a first direction and reflects light polarized in a second direction when a magnetic field is applied. The light polarized in the first direction transmitted by the color selective active polarizer has colors according to the dyes or color absorbing particles.

Abstract: A system and method to detect angular rotation, linear displacement and/or surface deformations is presented. The method is based on the ability of a linear polarized light to interact with magnetic materials and to change its polarization angle due to Faraday effect. A basic structure of the system consists of a magneto-optic (MO) film with a two-domain structure and a single domain wall which are generated by gradient magnetic field produced by opposite polarity permanent magnets placed near the film. An AC magnetic field applied perpendicular to the MO film surface causes the magnetic domain wall in the MO film to oscillate at the same frequency. This leads to a detected output AC modulated signal. By measuring the temporal changes in this signal, information on angular rotation, linear displacement and/or surface deformation can be obtained.

Abstract: Methods and apparatus for optical isolation in high peak power fiber-optic systems prevent damage to a facet within a fiber-optic isolator caused by back-reflected light from, for example, an optical amplifier. Preventing damage to the facet may include expanding a mode area of the back-reflected light and/or reducing a change in refractive index.

Abstract: Methods and systems for PMD compensation in an optical communication system are implemented by transmitting multiple optical signals through a common optical conduit to an optical compensator that adjustably rotates the polarization states of the multiple optical signals and transmits the rotated optical signals to an optical receiver. The receiver, upon sensing an excessive error condition, commands the optical compensator to change the polarization state of rotation, which changes the PMD profile of the received optical signals.

Abstract: It is possible to reduce the size of a magneto-optical device, increase the speed of optical control, simplify power supply structure and its control, and maintain a Faraday rotation angle in an arbitrary state even after shut-off of the excitation current. The magneto-optical device includes a magnetic yoke (10) made of a high-permeability magnetic material, the magnetic yoke including a tabular portion (16) and four pillar portions (18) protruding from one side of the tabular portion (16), a coil (12) wound on each of the pillar portions, and a magneto-optical element (14) arranged in an open-magnetic-circuit region surrounded by the end portions of the four pillar portions. A magnetic field obtained by a coil is applied to the magneto-optical element.

Abstract: A method of improving the security of a QKD system is disclosed. The QKD system exchanges qubits between QKD stations, wherein the brief period of time surrounding the expected arrival time of a qubit at a modulator in a QKD station defines a gating interval. The method includes randomly activating the modulator in a QKD station both within the gating interval and outside of the gating interval, while recording those modulations made during the gating interval. Such continuous or near-continuous modulation prevents an eavesdropper from assuming that the modulations correspond directly to the modulation of a qubit. Thus, an eavesdropper (Eve) has the additional and daunting task of determining which modulations correspond to actual qubit modulations before she can begin to extract any information from detected modulation states of the modulator.

Abstract: A single side band modulation device includes a first Mach Zehnder interferometer and a second Mach Zehnder interferometer. The first Mach Zehnder interferometer includes at least two output arms, and the second Mach Zehnder interferometer includes at least two output arms. Terminals of the output arms are connected with one another.

Abstract: An isolator is disclosed that features a single birefringent correction element. The correction element is configured to eliminate differential group delay and walk-off simultaneously.

Abstract: A magneto-optic variable optical attenuator is provided that is used to control the intensity of a light signal. The optical attenuator includes at least one polarizing element having an optical polarization axis, wherein the polarizing element transmits a portion of an incident light signal proportional to the angular difference between an optical polarization axis of the incident light signal and that of the polarizing element. The optical attenuator also comprises a variable faraday rotator that includes a semi-transparent material, a magnetic material for applying a magnetic force to a light signal that is passed through the semi-transparent material, and a conductive wire configured to induce a magnetic field on the magnetic material. In various embodiments, the optical attenuator is employed as part of a laser package that includes a laser light source and a plurality of polarizing elements, which are in optical communication with a faraday rotator and/or a variable faraday rotator.

Abstract: A magnetic, single-axis crystal is used to modify the polarization state of light, whereby light passes through pre-determined areas of the crystal. To change the polarization state of the light, a magnetic field pulse is applied to the crystal with a magnetic field amplitude, at which the crystal no longer remains in the single-domain state at the end of the pulse, but returns to a defined multi-domain state that is determined by the direction of the applied magnetic field, thus achieving large usable apertures of the switching element and extremely short change periods. According to the invention, energy is only required for the change operation and not for maintaining a specific state.

Abstract: Techniques and devices for depolarizing light and producing a variable differential group delays in optical signals. In one implementation, an input optical beam is split into first and second beams with orthogonal polarizations. One or two optical reflectors are then used to cause the first and second optical beams to undergo different optical path lengths before they are recombined into a single output beam. An adjustment mechanism may used implemented to adjust the difference in the optical path lengths of the first and second beams to produce a variable DGD. When the depolarization of light is desired, the difference in the optical path lengths of the first and second beams is set to be greater than the coherence length of the input optical beam.