An optical module includes: a substrate and a waveguide element having a mount face opposed to the substrate, the waveguide element having an interference waveguide portion having an optical interference function. Further, the mount face includes a projection region to which the interference waveguide portion is projected on the mount face and a non-projection region, and the waveguide element is joined to the substrate with a joint material in the non-projection region.

Pump reflectors for use in cladding-pumped fiber systems, such as laser or amplifier systems, are provided. The pump reflector includes an optical fiber segment having at least one core and at least one cladding. A cladding Bragg grating is written by femtosecond inscription in the optical fiber segment, and extending across at least a portion of the cladding. The cladding Bragg grating has a reflectivity profile encompassing the spectral profile of the pump and a spatial profile encompassing the pump spatial distribution in the cladding. A method of manufacturing a pump reflector using femtosecond light pulses is also provided.

Disclosed herein are electronic devices having touch input surfaces. A user's touch input or press on the touch input surface is detected using a set of lasers, such as vertical-cavity surface-emitting lasers (VCSELs) that emit beams of light toward the touch input surface. The user's touch causes changes in the self-mixing interference within the VCSEL of the emitted light with reflected light, such as from the touch input surface. Deflection and movement (e.g., drag motion) of the user's touch is determined from detected changes in the VCSELs' operation due to the self-mixing interference.

Disclosed are devices, methods, and systems for controlling output of a laser. An example device can comprise a first portion comprising a gain element and a second portion comprising a silicon material. The second portion can comprise a waveguide configured to receive light from the gain element, an optical resonator configured to at least partially reflect light back to the gain element via the waveguide, and a first tuning element configured to tune a resonant frequency of the optical resonator.

A tunable laser for a transceiver includes a silicon photonics substrate, first and second patterned regions each being defined in the substrate a step lower than a flat surface region of the substrate, first and second laser diode chips arranged in the first and second patterned regions, the patterned regions being configured to align the gain regions of the first and second laser diode chips with integrated couplers formed in the substrate adjacent to the first and second patterned regions to facilitate flip-bonding the first and second laser diode chips within the patterned regions, and a tuning filter coupled to the first laser diode chip and the second laser diode chip via the integrated couplers. The tuning filter is configured to receive laser light from each of the first and second laser diode chips and generate a laser output having a gain determined by each of the gain regions.

Disclosed herein are self-mixing interferometry (SMI) sensors, such as may include vertical cavity surface emitting laser (VCSEL) diodes and resonance cavity photodetectors (RCPDs). Structures for the VCSEL diodes and RCPDs are disclosed. In some embodiments, a VCSEL diode and an RCPD are laterally adjacent and formed from a common set of semiconductor layers epitaxially formed on a common substrate. In some embodiments, a first and a second VCSEL diode are laterally adjacent and formed from a common set of semiconductor layers epitaxially formed on a common substrate, and an RCPD is formed on the second VCSEL diode. In some embodiments, a VCSEL diode may include two quantum well layers, with a tunnel junction layer between them. In some embodiments, an RCPD may be vertically integrated with a VCSEL diode.

An optical path test system includes a return light test unit for emitting laser light to an optical path monitoring unit to simulate return light received by the optical path monitoring unit in a normal operation; a light path monitoring unit arranged on a light path of the return light testing unit for receiving the return light and normally emitting laser light; and a power detector for receiving the laser light emitted by the light path monitoring unit so as to monitor stability of output power of the chip when the light path monitoring unit receives the return light emitted by the return light testing unit. The technical solution in the present invention emits laser light to a tested laser chip to simulate return light received by the tested laser chip in a normal operation, and a return light resistance threshold of the laser chip can be accurately evaluated.

A non-reciprocal optical assembly for injection locking a laser to a resonator is described. The laser emits a light beam, and the resonator receives the light beam and returns a feedback light beam to the laser such that the feedback light beam causes injection locking. The non-reciprocal optical assembly is interposed between and optically coupled to the laser and the resonator. The non-reciprocal optical assembly includes a first port that receives the light beam from the laser, and a second port that outputs the light beam to the resonator and receives the feedback light beam from the resonator. The first port also outputs the feedback light beam to the laser. The light beam passes through the non-reciprocal optical assembly with a first power loss, and the feedback light beam passes through the non-reciprocal optical assembly with a second power loss (the first power loss differs from the second power loss).

Provided are a laser device and a method of transforming laser spectrum, which provide a laser frequency stabilization and significant narrowing a laser spectrum. A laser device includes at least one multiple longitudinal mode laser (L) for generating a laser light having a spectrum of multiple longitudinal modes; at least one high quality factor (high-Q) microresonator (M) optically feedback coupled to the at least one multiple longitudinal mode laser (L); and a tuner (TU) for tuning the spectrum of multiple longitudinal modes of the laser light. The laser device is configured to output an output laser light having an output spectrum with at least one dominant longitudinal laser mode each at a reduced linewidth of the dominant longitudinal laser mode. The laser device allows increasing an emission power of a narrow linewidth lasing without an additional amplification while keeping a compact size of a device with a limited number of optical elements.

A tunable laser for a transceiver includes a silicon photonics substrate, first and second patterned regions each being defined in the substrate a step lower than a flat surface region of the substrate, first and second laser diode chips arranged in the first and second patterned regions, the patterned regions being configured to align the gain regions of the first and second laser diode chips with integrated couplers formed in the substrate adjacent to the first and second patterned regions to facilitate flip-bonding the first and second laser diode chips within the patterned regions, and a tuning filter coupled to the first laser diode chip and the second laser diode chip via the integrated couplers. The tuning filter is configured to receive laser light from each of the first and second laser diode chips and generate a laser output having a gain determined by each of the gain regions.