Embodiments herein relate to a photonic integrated circuit (PIC) with an on-chip optical isolator. The PIC may comprise a laser, a waveguide coupled with the laser, and a closed loop resonator coupled to the laser through the waveguide. A magneto-optical (MO) layer is over and in contact with the waveguide and the closed loop resonator. The closed loop resonator may comprise a first polarization rotator (PR) and a second PR. A light from the laser in transverse electric (TE) mode through the waveguide is rotated in the first PR to a light in transverse magnetic (TM) mode, and the light in TM mode is rotated in the second PR to light in TE mode. The isolator may further comprise a micro-heater over or along a side of the waveguide and separated from the closed loop resonator; and a feedback control loop connected to the closed loop resonator and the micro-heater.

An optical module includes a light-forming part and a protective member. The light-forming part includes a base member, a semiconductor light-emitting device, a lens, and a light-receiving device mounted on the base member and disposed, in the emission direction of the semiconductor light-emitting device, between the semiconductor light-emitting device and the lens. The light-receiving surface of the light-receiving device inclines toward the emission portion of the semiconductor light-emitting device such that an inclination angle is more than 0 and 90 or less, the inclination angle being an angle formed between the optical axis of the semiconductor light-emitting device and a plane including the light-receiving surface of the light-receiving device.

There is set forth herein an optomechanical device which can comprise a first mirror and a second mirror forming with the first mirror a cavity. In one aspect the first mirror can be a movable mirror. The optomechanical device can be adapted so that the first mirror is moveable responsively to radiation force.

A multi-channel transmitter optical subassembly (TOSA) with an off-center fiber in an optical coupling is disclosed, and can provide passive compensation for beam displacement introduced by optical isolators. The optical coupling receptacle can include an optical isolator configured to receive a focused light beam from a focus lens within the TOSA. The optical coupling receptacle may be offset such that a center line of the focused light beam entering the optical isolator is offset from a center line of a fiber within optical coupling receptacle. Thus the optical isolator receives the focused light beam from the focus lens and introduces beam displacement such that an optical signal is launched generally along a center line of the fiber. Thus the expected beam displacement introduced by the optical isolator is eliminated or otherwise mitigated by the offset between a center line of the fiber and a center position of the focus lens.

A low-cost optical circuit, in which influence of reflected light is reduced, is provided. According to an embodiment of the present invention, an optical circuit (200) comprises a first optical coupler (204A) having at least two outputs, and a second optical coupler (204B) coupled to at least one of the outputs of the first optical coupler (204A), and wherein the ratio of an intensity of light reflected from the first optical coupler (204A) to an intensity of light inputted to the first optical coupler is smaller than the ratio of an intensity of light reflected from the second optical coupler (204B) to an intensity of light inputted to the second optical coupler.

A multi-channel transmitter optical subassembly (TOSA) with an off-center fiber in an optical coupling is disclosed, and can provide passive compensation for beam displacement introduced by optical isolators. The optical coupling receptacle can include an optical isolator configured to receive a focused light beam from a focus lens within the TOSA. The optical coupling receptacle may be offset such that a center line of the focused light beam entering the optical isolator is offset from a center line of a fiber within optical coupling receptacle. Thus the optical isolator receives the focused light beam from the focus lens and introduces beam displacement such that an optical signal is launched generally along a center line of the fiber. Thus the expected beam displacement introduced by the optical isolator is eliminated or otherwise mitigated by the offset between a center line of the fiber and a center position of the focus lens.

An integrated and compact multifunctional optical isolator (i.e., a combined splitter, isolator, and spot-size converter), which is suitable for use in a TOSA, includes input optics including a first polarizer, a Faraday rotator, and a second polarizer. The input optics include a wedge having a partially reflective coating disposed on a first face thereof. The input beam is incident on the first face at a non-normal angle of incidence such light passing through the wedge is refracted to a second face of the wedge, which is tilted relative to the first face by a predetermined wedge angle. At least one of the non-normal angle of incidence and the predetermined wedge angle is determined dependence upon a refractive index of the wedge material and a target anamorphic magnification of the input beam of light.

A head-mounted display (HMD) system includes a lens element supported by a support structure. The lens element includes a waveguide that includes an incoupler, an outcoupler, and an exit pupil expander. The incoupler is disposed within a first area of the waveguide. The outcoupler is disposed within a second area of the waveguide. The exit pupil expander is disposed within a third area of the waveguide. An anti-reflection coating is formed via fabrication used to form the incoupler, the outcoupler, and the exit pupil expander. The anti-reflection coating is disposed within a fourth area of the waveguide different than the first, second, and third areas of the waveguide.

A light receiving module having a built-in wavelength-tunable wavelength-selective filter that can selectively receive light with a specific wavelength from laser light with various wavelengths emitted from an optical fiber and tune the specific wavelength. In the light receiving module including a light receiving element having a built-in wavelength-tunable wavelength-selective filter that receives laser light from an optical fiber according to the present invention, a flat plate-shaped window (240) transmitting laser light from an optical fiber (600) is formed in the light receiving element (22), a wavelength-tunable wavelength-selective filter for separating wavelengths of laser light traveling as parallel light is disposed in the light receiving element (22), and a lens (400) converting laser light from the optical fiber (600) into parallel light is disposed between the optical fiber (600) and the light receiving element (22).

A photonics integrated circuit chip includes first and second optical waveguides formed on a semiconductor substrate. Light input into the first optical waveguide passes through a first optical isolator and a coupler formed on the substrate. The coupler outputs light from the first optical isolator combined with light from an off-substrate pump light source to an off-substrate optical fiber which outputs the combined light into the second optical waveguide for passage through a second optical isolator formed on the substrate. The substrate may also include third and fourth optical waveguides. Light input into the third optical waveguide passes through a third optical isolator and a second coupler formed on the substrate. The second coupler outputs light from the second optical isolator combined with light from the pump light source to an off-substrate second optical fiber which outputs the combined light into the fourth optical waveguide for passage through a fourth optical isolator formed on the substrate.