A laser device is provided which comprises a common waveguide layer and a plurality of laser bodies, wherein each of the laser bodies has an active region configured for generating coherent electromagnetic radiation. The laser bodies are arranged side by side on the common waveguide layer, wherein the laser bodies are directly adjacent to the common waveguide layer. In particular, the laser bodies are configured to be phase-coupled to each other via the waveguide layer during operation of the laser device.

Furthermore, a method for producing such a phase-coupled laser device is provided.

Structures for response shaping in frequency and time domain, include an optical response shaper and/or a modulator device with multiple injection. The device comprises a resonator having an enclosed geometric structure, for example a ring or racetrack structure, at least two injecting optical waveguides approaching the resonator to define at least two coupling regions between the resonator and the injecting waveguides, and may define at least two Free Spectral Range states. One or both of the coupling regions has a coupling coefficient selected for a predetermined frequency or time response, and the coupling coefficient or other device parameters may be variable, in some case in real time to render the response programmably variable.

Techniques to achieve higher power/shorter pulses with a laser diode. By initially applying a static reverse bias across the laser diode, the laser diode can turn on at a larger inductor current. When the laser diode is initially reverse biased, depletion charge and diffusion charge can be populated before the laser diode will lase. This causes the laser diode to initially turn on at a larger inductor current, which will reduce the rise time, thereby achieving higher power/shorter pulses.

This application describes a wavelength-tunable laser apparatus, which reduces complexity of wavelength tuning of a laser. The laser includes a reflective gain unit, an optical phase shifter, a coupler, and a passive filter unit array. Furthermore, an output port of the reflective gain unit is connected to an input port of the optical phase shifter, an output port of the optical phase shifter is connected to an input port of the coupler, a first output port of the coupler is connected to an input port of the passive filter unit array, and a second output port of the coupler is an output port of the laser. The passive filter unit array includes a plurality of passive filter units, where any two of the plurality of passive filter units have different wavelength tuning ranges, and each filter unit has a linearly tunable wavelength.

A method for generating single optical pulses of picosecond-range duration with suppressed transient emission tails.

Techniques to achieve higher power/shorter pulses with a laser diode. By initially applying a static reverse bias across the laser diode, the laser diode can turn on at a larger inductor current. When the laser diode is initially reverse biased, depletion charge and diffusion charge can be populated before the laser diode will lase. This causes the laser diode to initially turn on at a larger inductor current, which will reduce the rise time, thereby achieving higher power/shorter pulses.

Optical systems can emit train(s) of light pulses onto objects to derive a distance between the light source and the object. Achieving meter or centimeter resolution may require very short light pulses. It is not trivial to design a circuit that can generate narrow current pulses for driving a diode that emits the light pulses. An improved driver circuit has a pre-charge path comprising one or more inductive elements and a fire path comprising the diode. Switches in the driver circuit are controlled with predefined states during different intervals to pre-charge current in the one or more inductive elements prior to flowing current through the fire path to pulse the diode.

A light source device according to an embodiment is used with a light guide member and a wavelength converting member, and includes a light-emitting element, a light sensor, and a driving unit. The light-emitting element radiates a light beam to be incident on a first end of the light guide member by being supplied with a drive current. The light sensor detects signal light, which has been incident on a second end of the light guide member and transmitted to the first end. The driving unit supplies the drive current to the light-emitting element and controls the drive current based on a result of detection of the signal light.

An optical logic device includes a distributed feedback laser configured to generate a first signal corresponding to distributed feedback laser output signal, the first signal being at a first wavelength. The device further includes a bandpass filter having a center frequency corresponding to the first wavelength. Additionally, the device can include an optical circulator having a first port coupled to a logic device input signal, a second port coupled to the first signal, and a third port coupled to the bandpass filter, wherein when the logic device input signal has a power above a predetermined threshold and there is a wavelength difference between the first wavelength and an input wavelength of the logic device input signal, a suppression of the first signal occurs.

An optical logic device includes a distributed feedback laser configured to generate a first signal corresponding to distributed feedback laser output signal, the first signal being at a first wavelength. The device further includes a bandpass filter having a center frequency corresponding to the first wavelength. Additionally, the device can include an optical circulator having a first port coupled to a logic device input signal, a second port coupled to the first signal, and a third port coupled to the bandpass filter, wherein when the logic device input signal has a power above a predetermined threshold and there is a wavelength difference between the first wavelength and an input wavelength of the logic device input signal, a suppression of the first signal occurs.