In an example, an optical system includes a fiber, a detector, and a gradient-index (GRIN) lens assembly. The GRIN lens assembly is positioned between the fiber and the detector and couples light from an exit aperture of the fiber onto the detector. The spot size of light exiting the fiber is larger than a spot size of light exiting the GRIN lens assembly. Additionally, the spot area of light exiting the GRIN lens assembly may be smaller than a sensing area of the detector. Among other advantages, the GRIN lens assembly increases the amount of light coupled onto the detector from the fiber. Additionally, the GRIN lens assembly may make the optical system more robust against vibrations (and other factors) that change the energy distribution of light exiting the fiber.

A light source unit generates an optical signal out of a bend-insensitive (“BI”) optical fiber that is compliant with a desired encircled flux (“EF”). The unit includes a light source to generate an optical light signal and a conventional multimode optical fiber coupled to receive the optical light signal from the light source at a first end. A modal conditioner is arranged to condition the optical light signal propagating along different modes of the conventional multimode fiber. A first bend-insensitive (BI) multimode optical fiber has an input end, the input end of the first BI multimode optical fiber being coupled at a second end of the conventional multimode optical fiber to receive the conditioned optical light signal from the conventional multimode fiber. The output from the first BI multimode optical fiber outputs an optical signal having the desired EF.

A light source device includes an optical fiber; a beam light source configured to coaxially combine laser beams of different peak wavelengths to generate and emit a wavelength-combined beam; and an optical coupling device configured to allow the wavelength-combined beam emitted from the beam light source to be incident on the optical fiber. The optical coupling device includes a first cylindrical lens configured to focus the wavelength-combined beam in a first plane and having a first focal length, a second cylindrical lens configured to focus the wavelength-combined beam in a second plane and having a second focal length, and a third cylindrical lens having a third focal length greater than the first focal length and configured to focus the wavelength-combined beam in the first plane to be incident on the first cylindrical lens.

Various embodiments may relate to an optical system. The optical system may include a lens structure configured to generate an outgoing Gaussian beam based on an incoming Gaussian beam. The optical system may also include a light source configured to provide the incoming Gaussian beam to the lens structure. The lens structure may be a flat lens or a phase plate.

Provided is a photoelectric detector, comprising: a silicon layer (110), the silicon layer (110) comprising a first-doping-type doped region (111); a germanium layer (120) in contact with the silicon layer (110), the germanium layer (120) comprising a second-doping-type doped region (121); and a silicon nitride waveguide (130), the silicon nitride waveguide (130) being arranged surrounding the germanium layer (120) along the extension directions of at least three side walls of the germanium layer (120), wherein the silicon nitride waveguide (130) is used for transmitting an optical signal and coupling the optical signal to the germanium layer (120), and the germanium layer (120) is used for detecting the optical signal and converting the optical signal into an electrical signal.

A device for combining several light beams, the device including several hollow input waveguides, at least one per light beam, as well as a hollow output waveguide which is the same for the different light beams, each input waveguide having an input opening to let the corresponding light beam enter, and, at the opposite, an output opening through which it emerges in the output waveguide, the output waveguide, as well as each input waveguide being laterally delimited by one or more metallic reflecting surfaces, and wherein at least a section of the output waveguide is divergent and widens in the direction of an output opening of the output waveguide.

A system includes a housing including a front panel, a rear panel, an upper panel, and a lower panel. The system includes a first circuit board or substrate, at least one data processor coupled to the first circuit board or substrate and configured to process data, and at least one optical module coupled to the first circuit board or substrate. Each optical module is configured to perform at least one of (i) convert input optical signals to electrical signals that are provided to the at least one data processor, or (ii) convert electrical signals received from the at least one data processor to output optical signals. The system includes at least one inlet fan mounted near the front panel and configured to increase an air flow across a surface of at least one of (i) the at least one data processor, (ii) a heat dissipating device thermally coupled to the at least one data processor, (iii) the at least one optical module, or (iv) a heat dissipating device thermally coupled to the at least one optical module. The system includes at least one laser module configured to provide optical power to the at least one optical module.

An optical receptacle includes a first optical surface, a second optical surface, and an annular first cylindrical part disposed to surround a second central axis of the second optical surface. The first cylindrical part includes a first inner surface with a circular shape in a cross section perpendicular to the second central axis, and a second inner surface disposed on a second optical surface side than the first inner surface and provided with a circular shape in the cross section perpendicular to the second central axis. A diameter of the first inner surface is greater than a diameter of the second inner surface, and a length of the second inner surface in a direction along the second central axis is 0.5 to 4.0 mm.

A light source unit includes: a sealed semiconductor laser package including a laser diode that includes an emitter region from which laser light is emitted, the emitter region located at a surface of the laser diode, and a window member configured to transmit the laser light; a first lens structure configured to receive the laser light transmitted through the window member and create an image of the emitter region on an image plane; and a second lens structure configured to convert the laser light having passed through the image plane into a collimated or converged beam, and to emit the collimated or converged beam.

A structure for optically aligning an optical fiber to a protonic device and method of fabrication of same. The structure optically aligns an optical fiber to the protonic device using a lens between the two which is moveable by actuator heads. The lens is moveable by respective motive sources associated with the actuator heads.