A light emission assembly including: a substrate; at least two channels including: a driving assembly including a driving chip; an EML laser assembly including an EML laser chip; a first magnetic bead; a second magnetic bead; a DC blocking capacitor; a driving multiplexing pad for electrically connecting a first end of the first magnetic bead with a signal pad of the driving chip and a first end of the DC blocking capacitor, a second end of the first magnetic bead being connected to a first supply voltage; an EML multiplexing pad for electrically connecting a first end of the second magnetic bead with the EML laser chip assembly and a second end of the DC blocking capacitor, a second end of the second magnetic bead being connected to a supply voltage of the EML laser chip. The present disclosure also provides an optical module including the light emission assembly.

A method of generating an optical pulse train using spectral extension by optical phase modulation, spectral narrowing by optical phase demodulation, and narrow linewidth optical filtering is disclosed. It is also described that the wavelength selection of light using a chromatic dispersion element between the optical phase modulator can enrich the method. Systems include an in-line optical setup and a ring-type laser cavity for mode-locked laser outputs. The duration with which the electrical signals driving the modulators are opposed determines the line width of the optical pulses, and the opposite repetition of the electrical signals defines the rate of repetition of an optical pulse train generated. Four different arrangements of electrical signals in the time domain or phase domain make it possible to control the generation of optical pulses and the wavelength selection of the light. (i) A signal arrangement comprising sinusoidal electrical signals with a slight frequency difference. (ii) A signal arrangement comprising a phase-shift between electrical signals. (iii) A signal arrangement comprising a phase-shift between electrical signals depending on the amplitude of the bits. (iv) A signal arrangement comprising random electric waves that repeat themselves over a predefined period to allow the insertion of controllable time delays between each other.

Described herein are methods for developing and maintaining pulses that are produced from compact resonant cavities using one or more Q-switches and maintaining the output parameters of these pulses created during repetitive pulsed operation. The deterministic control of the evolution of a Q-switched laser pulse is complicated due to dynamic laser cavity feedback effects and unpredictable environmental inputs. Laser pulse shape control in a compact laser cavity (e.g., length/speed of light <˜1 ns) is especially difficult because closed loop control becomes impossible due to causality. Because various issues cause laser output of these compact resonator cavities to drift over time, described herein are further methods for automatically maintaining those output parameters.

Example optical amplification apparatus and example signal amplification methods are provided. One example optical amplification apparatus is connected to an optical fiber. The optical amplification apparatus includes a first pump laser and a first gain medium. The first pump laser is configured to emit first pump light. The first gain medium is configured to receive the first pump light and first multi-channel optical signals from the optical fiber; and perform gain amplification on the first multi-channel optical signals based on the first pump light, where the first pump light overlaps each of the first multi-channel optical signals in the first gain medium.

Systems, apparatuses, and methods are provided for dual-pass amplification of laser beams along a common beam path. An example method can include generating a first laser beam and a second laser beam. Subsequently, the example method can include performing dual-pass amplification of the first laser beam and the second laser beam along a common beam path. In some aspects, the first laser beam can include a first wavelength, the second laser beam can include a second wavelength different from the first wavelength.

A laser system including a seed laser, a laser beam splitting and combining subsystem receiving an output from the seed laser and providing a combined laser output having noise and a noise cancellation subsystem operative to provide a noise cancellation phase correction output based on taking into consideration the noise at intermittent times, the laser beam splitting and combining subsystem varying a phase of the combined laser output during time interstices between the intermittent times.

Optical line amplifiers with on-board controllers and supervisory devices for controlling optical line amplifiers are provided for controlling bootstrap or power-up procedures when optical line amplifiers are initially installed in an optical communication network. The controllers may include non-transitory computer-readable medium configured to store computer logic having instructions that, when executed, cause one or more processing devices to block an input to one or more gain units of the line amplifier and cause the line amplifier to operate in an Amplified Spontaneous Emission (ASE) mode. In response to a detection of a valid power level of the line amplifier, the instructions can further cause the one or more processing devices to switch the line amplifier from the ASE mode to a regular mode and unblock the input to the one or more gain units of the line amplifier to allow operation of the line amplifier in the regular operating mode.

A receiving device includes a light source outputting local oscillation light, a detector detecting intermittent input of a burst light signal by using the local oscillation light, a first converter converting the detected burst optical signal into an electrical analog signal, an amplifier amplifying the analog signal according to a gain, a second converter converting the amplified analog signal into a digital signal, and a setting processor setting the gain of the amplifier and a wavelength of the local oscillation light instructed by a control device when setting a communication line with one of transmitting devices transmitting the burst optical signal, wherein, before setting the communication line, the setting processor switches the wavelength of the local oscillation light according to the burst optical signal transmitted from each of the transmitting devices, adjusts the gain of the amplifier and notifies the control device of the adjusted gain.

The present disclosure provides a method for aligning a master oscillator power amplifier (MOPA) system. The method includes ramping up a pumping power input into a laser amplifier chain of the MOPA system until the pumping power input reaches an operational pumping power input level; adjusting a seed laser power output of a seed laser of the MOPA system until the seed laser power output is at a first level below an operational seed laser power output level; and performing a first optical alignment process to the MOPA system while the pumping power input is at the operational pumping power input level, the seed laser power output is at the first level, and the MOPA system reaches a steady operational thermal state.

A laser apparatus may include: a quantum cascade laser outputting, based on a supplied current, laser light at an oscillation start timing when a first delay time elapses from a current rising timing of the supplied current: an amplifier disposed in a laser light optical path, and selectively amplifying light of a predetermined wavelength to output the amplified laser light to a chamber including a plasma generation region into which a target is fed; and a laser controller controlling a third delay time, from an output timing of a laser output instruction to the current rising timing, to cause a laser light wavelength to be equal to the predetermined wavelength at an aimed timing when a second delay time elapses from the oscillation start timing, based on oscillation parameters including the first delay time, a supplied current waveform, and a device temperature of the quantum cascade laser.