H01S5/0261

DRIVER CIRCUIT FOR EVALUATION OF AN OPTICAL EMITTER
20230051475 · 2023-02-16 ·

A driver circuit may include an optical emitter, a capacitive element, and an inductive element. The driver circuit may include a first switch that, in a closed state, is to cause charging of the inductive element, and when transitioning from the closed state to an open state is to cause discharging of the inductive element to charge the capacitive element. The driver circuit may include a second switch that in a closed state is to cause discharging of the capacitive element to provide an electrical pulse to the optical emitter. The driver circuit may include a signal generator configured to generate a first signal for controlling the open state and the closed state of the first switch, and a pulse shortening element configured to shorten a pulse width of the first signal to generate a second signal for controlling the open state and the closed state of the second switch.

High power, narrow linewidth semiconductor laser system and method of fabrication

A laser system for generating a narrow linewidth semiconductor light beam includes a substrate, a gain chip affixed on the substrate and configured to amplify light beam, and an optical feedback photonic chip affixed on the substrate, optically coupled to the gain chip, and configured to output light beam, which has a narrow linewidth around a resonant frequency of the optical feedback photonic chip, to the gain chip. The optical feedback photonic chip includes first and second optical gratings, a first multimode interferometer (MMI) and a second MMI optically coupled with a respective end of the first and second optical gratings, a third MMI configured to output two light beams to the first and second MMIs, respectively, through a respective waveguide. Based on receiving a respective one of the two light beams, the first MMI outputs two light beams to its respective end of the first and second optical gratings and the second MMI outputs two light beams to its respective end of the first and second optical gratings, the first and second optical gratings output second and third light beams, the second light beam, of which a linewidth is narrower than a linewidth of the third light beam, is directed to the third MMI, and an output port of the third MMI is configured to direct the second light beam to the gain chip.

Integrated laser source

Integrated laser sources emitting multi-wavelengths of light with reduced thermal transients and crosstalk and methods for operating thereof are disclosed. The integrated laser sources can include one or more heaters and a temperature control system to maintain a total thermal load of the gain segment, the heater(s), or both of a given laser to be within a range based on a predetermined target value. The system can include electrical circuitry configured to distribute current to the gain segment, the heater(s), or both. The heater(s) can be located proximate to the gain segment, and the distribution of current can be based on the relative locations. In some examples, the central laser can be heated prior to being activated. In some examples, one or more of the plurality of lasers can operate in a subthreshold operation mode when the laser is not lasing to minimize thermal perturbations to proximate lasers.

TRANSIENT WAVELENGTH DRIFT REDUCTION IN SEMICONDUCTOR LASERS

This application relates to a laser assembly displaying self-heating mitigation. The laser assembly comprises a semiconductor laser and a drive unit for driving the semiconductor laser. The semiconductor laser includes a first semiconductor region for generating or modulating an optical signal in response to a first drive current that is applied to the first semiconductor region, and a heating region that is arranged in proximity to the first semiconductor region and electrically insulated from the first semiconductor region. The drive unit is configured to generate the first drive current and a second drive current, apply the first drive current to the first semiconductor region during respective transmission periods of the semiconductor laser, and apply the second drive current to the heating region in intervals between successive transmission periods.

SILICON PHOTONIC CHIP WITH INTEGRATED ELECTRO-OPTICAL COMPONENT AND LENS ELEMENT

Embodiments include a silicon photonic chip having a substrate, an optical waveguide on a surface of the substrate and a cavity. The cavity includes an electro-optical component, configured for emitting light perpendicular to said surface and a lens element arranged on top of the electro-optical component. The lens is configured for collimating light emitted by the electro-optical component. The chip also includes a deflector arranged on top of the lens element and configured for deflecting light collimated through the latter toward the optical waveguide. The lens element includes electrical conductors connected to the electro-optical component. The electrical conductors of the lens element may for instance include one or more through vias, one or more bottom electrical lines on a bottom side of the lens element (facing the electro-optical component), and at least one top electrical line.

Decoupling layer to reduce underfill stress in semiconductor devices

An integrated circuit assembly includes a support (e.g., package substrate or circuit board) and a semiconductor die including a device. The semiconductor die is mounted to the support with the device facing the support. The device can be, for example, a quantum well laser device or a photonics device. A layer of decoupling material is on the device. An underfill material is between the semiconductor die and the support, where the decoupling material is between the device and the underfill material. The decoupling layer decouples stress from transferring from the underfill material into the device. For example, the decoupling material forms only weak bonds with the underfill material and/or a passivation layer on the device, in an embodiment. Weak bonds include non-covalent bonds and non-ionic bonds, for example. The decoupling material can be, for instance, a PTFE film, a poly(p-xylylene) film, a fluorocarbon, or a compound lacking free hydroxyl groups.

LIGHT-EMITTING APPARATUS AND MANUFACTURING METHOD THEREOF

A decrease in image quality is suppressed. A solid-state imaging apparatus according to an embodiment includes: a photoelectric conversion unit (PD) including a material having a smaller band gap energy than silicon; and a circuit board joined to the photoelectric conversion unit, the circuit board including: a pixel signal generation circuit that generates a pixel signal having a voltage value corresponding to a charge generated in the photoelectric conversion unit; and a thermometer circuit that detects a temperature of the circuit board.

OPTICAL ASSEMBLY WITH A MICROLENS COMPONENT AND CONTACTS ON A SAME SURFACE OF A VERTICAL CAVITY SURFACE EMITTING LASER DEVICE

In some implementations, an optical assembly includes a substrate that includes a thermally conductive core, an IC driver chip that is disposed on a first surface of the substrate, and a VCSEL device that includes an electrically insulated surface that is disposed on the thermally conductive core of the substrate within a cavity formed in the second surface of the substrate. The VCSEL device includes a cathode contact disposed on a surface of the VCSEL device and an anode contact disposed on the surface of the VCSEL device. The VCSEL device includes a plurality of emitters and a microlens component that is disposed over the plurality of emitters on the surface of the VCSEL device.

Optical pulse emitter

Disclosed herein is a method of optical pulse emission including three phases. During a first phase, a capacitor is charged from a supply voltage node. During a second phase, a voltage stored on the capacitor is boosted, and then the capacitor is at least partially discharged through a light emitting device. During a third phase, the capacitor is further discharged by bypassing the light emitting device. The third phase may begin prior to an end of the second phase.

Heater-integrated ridge type optical semiconductor optical device

A ridge type semiconductor optical device includes a first conductivity type semiconductor layer including at least a first stripe section; an active layer including at least an active stripe section on the first stripe section; a second conductivity type semiconductor layer including at least a second stripe section on the active stripe section; a ridge electrode on the second stripe section; an insulation film on an end face of each of the first stripe section, the active stripe section, and the second stripe section; and a film heater on the insulation film, the film heater overlapping with the end face of at least the first stripe section.