Abstract: An optical grating coupler defining an axis and configured to couple light between a planar waveguide and an optical fiber, including first and second entry surfaces and a plurality of scattering regions symmetric to the axis and arranged such scattering strength presented to incoming light by the plurality of scattering regions changes from weak to strong along a beam path of the incoming light to match a Gaussian mode profile of the optical fiber.

Abstract: A light pulse source and method for generating repetitive optical pulses are described. The light pulse source includes a continuous wave cw laser device, an optical waveguide optically coupled with the laser device, an optical microresonator, and a tuning device. The optical microresonator coupling cw laser light via the waveguide into the microresonator, which, may include, a light field in a soliton state with soliton shaped pulses coupled out of the microresonator for providing the repetitive optical pulses. The laser device includes a chip based semiconductor laser, the microresonator and/or the waveguide may reflect an optical feedback portion of light back to the semiconductor laser, which may provide self-injection locking relative to a resonance frequency of the microresonator. The tuning device is arranged for tuning at least one of a driving current and a temperature of the semiconductor laser such that the microresonator may provide the soliton state.

Abstract: A telecommunications module defines an interior with separate right and left chambers. An optical component is housed within the left chamber. Signal input and output locations are exposed to the right chamber. The right chamber allows excess fiber to accumulate without bending in a radius smaller than a minimum bend radius. A dual-layered cable management structure is positioned within the right chamber that defines a lower cable-wrapping level and a separate upper cable-wrapping level. The upper cable-wrapping level is defined by a removable cable retainer mounted on a spool defining the lower-cable wrapping level. Cabling carrying the input and output signals are passed between the right and left chambers before and after being processed by the optical component.

Abstract: A method and system for operating a frequency comb. The method may comprise operating an electro-optic (EO) frequency comb with two phase-locked microwave signals to produce an optical output, detecting the optical output with an optical receiver as one or more beat notes, and detecting the one or more beat notes with a radio-frequency spectrum analyzer. The system may comprise an EO frequency comb and an EO phase modulator disposed in the bulk nonlinear crystal resonator. The EO frequency comb may further comprise a continuous-wave laser and a bulk nonlinear crystal resonator connected to the continuous-wave laser.

Abstract: Provided is a waveguide photodetector including a semiconductor substrate, a first optical waveguide and a second optical waveguide, which are sequentially laminated on the semiconductor substrate, in which each of the first optical waveguide and the second optical waveguide includes a first portion and a second portion, and the first portion extends from the second portion in a first direction parallel to a top surface of the semiconductor substrate, a refractive index matching layer disposed on the second portion of the second optical waveguide, a clad layer disposed on the refractive index matching layer, and an absorber disposed between the refractive index matching layer and the clad layer. Here, the second optical waveguide has a first conductive-type, the clad layer has a second conductive-type opposite to the first conductive-type, and the refractive index matching layer includes a first semiconductor layer that is an intrinsic semiconductor layer.

Abstract: A harmonic light-generating metasurface includes a base substrate and a plurality of structures, that include nonlinear material, that are disposed in a pattern on a surface of the base substrate. Each structure of the plurality of structures individually supports a magnetic dipole mode. An electromagnetic field enhancement of the magnetic dipole mode induces generation of a harmonic signal by the plurality of structures. Alternatively, a harmonic light-generating metasurface, includes a base substrate, a supporting substrate that includes a nonlinear material, and a plurality of paired structures disposed in a pattern on a surface of the supporting substrate. Each paired structure, of the plurality of paired structures, collectively supports a toroidal dipole mode. An electromagnetic field enhancement of the toroidal dipole mode penetrates the supporting substrate to induce generation of a harmonic signal by the supporting substrate.

Abstract: In various embodiments, a beam-parameter adjustment system and focusing system alters a spatial power distribution of a radiation beams before the beam is coupled into an optical fiber or delivered to a workpiece.

Abstract: A technique to generate terahertz radiation is disclosed, where a pump beam (12) is coupled into an optical element (50) made of a medium with non-linear optical properties having plane-parallel front and rear boundary surfaces (51, 52), wherein the pump beam (12) is split into a set of partial pump beams (121) by reflection and/or diffraction on a periodic relief structure (53) of said optical element (50). The partial pump beams travel along a direction at an angle ? that satisfies the velocity matching condition of vp,cs cos(?)=vTHz,f within the given medium, where vp,cs is the group velocity of the pump beam, vTHz,f is the phase velocity of the terahertz radiation and the speed a planar envelope (212) travels toward the front boundary surface (51) of the optical element (50), and angle ? is the angle formed by the pulse front envelope and the phase front of the pump beam.

Abstract: Disclosed by the present invention is an ultra-wideband white noise source based on a slicing super-continuum spectrum. The entropy source used is a super-continuum spectrum photon entropy source having a coverage range of several hundreds of nm, white noise can thus be generated in a wide frequency range, thereby effectively avoiding the bandwidth bottleneck of an electronic device. By separately adjusting the filter centers of two optical filters, the center frequency for generating the white noise can be adjusted so as to get adapted to different working situations. High bandwidth white noise can be generated by simply filtering the super-continuum spectrum and performing photoelectric conversion, and in comparison with the previous solutions, the solution of the present invention is simpler and can be easily implemented.

Abstract: A pulsed laser output section outputs a laser beam having a predetermined wavelength as first pulses. An optical path determining section receives the first pulses and determines one among a plurality of optical paths for each of the first pulses for output. A parallelizing section parallelizes a traveling direction of light beams traveling, respectively, through the plurality of optical paths. A wavelength changing section receives outputs from the parallelizing section and changes the outputs to have different wavelengths for output. A focusing section receives and focuses outputs from the wavelength changing section. An optical fiber receives an output from the focusing section at a core end face. A timing control section is arranged to time outputs from the optical path determining section to the output of the first pulses. The focusing section is arranged to focus the outputs from the wavelength changing section on the core end face.

Abstract: A shutter assembly for a dual polarity fiber optic adapter is provided. The shutter assembly disposed in the dual polarity fiber optic adapter may eliminate dust accumulation and obstruct light beams emission, thus preventing eyes from a user from exposure to the light beams. Furthermore, an extending tab formed in the dual polarity fiber optic adapter may also prevent misplacement of fiber optic connector during installation.

Abstract: An OPO including a resonator comprising a material having a nonlinear susceptibility generating an output electromagnetic field in response to a pump electromagnetic field inputted into the material. The output electromagnetic field has one or more output wavelengths longer than one or more pump wavelengths of the pump electromagnetic field. The resonator has dimensions less than, or on the order of, the one or more output wavelengths in free space.

Abstract: The present disclosure relates to a re-enterable enclosure for a fiber optic network. The enclosure can include features such as a low compression-force perimeter gasket, cable seals constructed to seal effectively seal triple points, multi-function port size reducer plugs and multi-function blind plugs.

Abstract: It remains a challenge to generate coherent radiation in the spectral range of 0.1-10 THz (“the THz gap”), a band for applications ranging from spectroscopy to security and high-speed wireless communications. Here, we disclose how to produce coherent radiation spanning the THz gap using efficient second-harmonic generation (SHG) in low-loss dielectric structures, starting from an electronic oscillator (EO) that generates coherent radiation at frequencies of about 100 GHz. The EO is coupled to cascaded, hybrid THz-band dielectric cavities that combine (1) extreme field concentration in high-quality-factor resonators with (2) nonlinear materials enhanced by phonon resonances. These cavities convert the input radiation into higher-frequency coherent radiation at conversion efficiencies of >103%/W, making it possible to bridge the THz gap with 1 W of input power.

Abstract: A laser light source for producing incoherent laser beams, in particular for speckle-free imaging and/or projection, with at least two different wavelengths, preferably with three different wavelengths, includes: at least two optical devices, in particular at least two optical parametric oscillators, which each have a nonlinear optical medium for respectively producing a signal beam and an idler beam, and a superposition device configured to respectively superpose either the signal beam or the idler beam of each of the at least two optical devices for producing an incoherent laser beam with the at least two different wavelengths. A laser projector for producing an image, in particular a speckle-free image, on a projection surface, can include such a laser light source.

Abstract: An electronic device may have a display that displays an image and a display cover layer that overlaps the display. The display cover layer may have an image transport layer with an input surface that receives the image and a corresponding output surface to which the image is transported. The image transport layer may be formed from a coherent fiber bundle layer or a layer of Anderson localization material. The display cover layer may have a protective layer such as a protective glass layer that overlaps the image transport layer. A ring-shaped region of the display cover layer may have one or more structures with locally modified properties for arresting crack propagation across the display cover layer. The ring-shaped region may have one or more structures with locally reduced elasticity values or other structures that help arrest cracks.

Abstract: A laser device includes a light source configured to emit a laser light, a first mirror and a second mirror constituting a resonator where a laser light emitted from the light source enters, a nonlinear optical medium located between the first mirror and the second mirror, and a dispersive medium of adjustable effective optical thickness located between the nonlinear optical medium and at least one of the first mirror and the second mirror.

Abstract: An optical waveguide includes an input diffractive optical element arranged for being aligned with an optical projector for diffracting the light beam therefrom, a waveguide substrate arranged for reflecting the light beam diffracted by the input diffractive optical element by means of total internal reflection, and an output diffractive optical element coupled at said waveguide substrate for partially diffracting the light beam as a diffracted light and partially transmitting the light beam as a transmitted light during the total internal reflection of the light beam within the waveguide substrate. The diffracted light is diffracted by the output diffractive optical element and is projected out of the waveguide substrate toward the user eye. The transmitted light is continuously transmitted and reflected within the waveguide substrate by the total internal reflection until the transmitted light is totally diffracted out of the waveguide substrate, so as to complete an exit pupil expansion.

Abstract: Systems and methods for a tunable radio frequency synthesizer utilizing optical frequency combs are provided. In one embodiment, an RF signal generator comprises: an SBS pump laser segment including a first and second SBS pump laser each generating SBS laser light at different respective frequencies; a TE/TM dual comb resonator comprising a comb optical resonator coupled to the first and second SBS pump lasers, wherein the comb optical resonator generates a pair of counter-propagating optical frequency combs of different polarities from the SBS laser light; a filter resonator segment configured to provide feedback to the TE/TM dual comb resonator to lock a relative position of the pair of counter-propagating optical frequency combs, the filter resonator comprising a tunable optical filter to output a discrete tuned RF signal output based on a comb line pair that includes a single comb line from each of the pair of counter-propagating optical frequency combs.

Abstract: A photodetector structure includes a substrate including a semiconductor film, a light absorption layer which is in contact with the semiconductor film and includes germanium (Ge), on the substrate, a first coating layer which wraps at least a part of a side surface of the light absorption layer, on the substrate, and an optical waveguide which is in contact with the light absorption layer and includes silicon nitride (SiN), on the first coating layer, wherein a lower surface of the optical waveguide is higher than a lower surface of the light absorption layer.