In some implementations, an amplifier device may include a first amplifier configured to amplify signals in a first range of optical wavelengths. The first amplifier may include a first portion that includes one or more first optical gain components, and a second portion that includes one or more second optical gain components and a variable optical attenuator. The amplifier device may include a second amplifier configured to amplify signals in a second range of optical wavelengths. The amplifier device may include a filter for the first range of optical wavelengths and the second range of optical wavelengths. The filter may be located between the first portion and the second portion of the first amplifier.

A laser clock signal generator for controlling a laser beam generator to generate pulse laser radiation is provided. The laser clock signal generator includes a clock signal specification input arranged to receive an external clock specification signal, a basic clock signal generator configured to generate a basic clock signal based on the external clock specification signal and output the basic lock signal at a clock signal output to the laser beam generator, and a controller configured to control the basic clock generator, for example, to be synchronized with the external clock specification signal. The laser clock signal generator also includes an overclocking protector arranged between the basic clock generator and the clock signal output.

Disclosed is a laser system including a source, for generating a source signal, and an optical amplifier system. The laser system includes a pulse selection or variation device configured to select or vary the source signal so as to form a main signal composed of one or more light pulses. The main signal is temporally variable in terms of rhythm and/or amplitude. The laser system is configured to inject the main signal and a secondary signal into the optical amplifier system. The secondary signal is varied on the basis of the temporal variation in terms of rhythm and/or amplitude of the main signal so as to stabilize the power stored in the optical amplifier system in a time-dependent manner, and the laser system is configured to spatially separate the amplified main signal from the amplified secondary signal.

A signal light interruption detection device includes an optical interleaver to demultiplex wavelength-multiplexed light into light in first frequency ranges corresponding to a first frequency grid including frequencies at regular frequency intervals in which a main signal light component can be arranged and light in second frequency ranges corresponding to a second frequency grid shifted from the first frequency grid by a half cycle of the regular frequency intervals, a first optical detector to detect first light power as total power of the light in the first frequency ranges, a second optical detector to detect second light power as total power of the light in the second frequency ranges, and a judgment unit to output a notification signal based on a difference between the first light power detected by the first optical detector and the second light power detected by the second optical detector.

An optical amplifier repeater system includes an optical fiber propagating a light beam in a plurality of propagation modes and an optical amplifier repeater amplifying the light beam propagated through the optical fiber. The optical amplifier repeater includes an optical demultiplexer demultiplexing the light beam in the plurality of propagation modes propagated through the optical fiber into a plurality of single-mode light beams, an optical amplifier amplifying, by simultaneous pumping, intensities of the plurality of single-mode light beams using a light beam generated by one pumping light source, an optical multiplexer multiplexing the plurality of single-mode light beams amplified by the optical amplifier into a light beam in the plurality of propagation modes, and an optical intensity adjusting unit adjusting the intensity of each of the plurality of single-mode light beams at least one of before or after the amplification by the optical amplifier. The optical intensity adjusting unit performs the adjustment by amplifying or attenuating the optical intensity of each of the plurality of single-mode light beams in an individual optical path through which the single-mode light beam is propagated.

The ultrafast pulse fiber laser system is configured with scalable output power and operative to reduce degradation of pulse integrity. The disclosed laser system is configured to suppress the pulse distortion through improvement of initial pulse contrast between main and side pulses and improved pulse shape using chirped pulse amplification and a fast intensity modulator driver by a corrected electrical signal that is generated from the original optical signal. The structure providing the improvement includes the photodiode, which is operative to measure the chirped optical pulse and convert it to the electrical signal, and analog electronics that quickly converts the electrical signal to the required signal that suppress the side pulses.

It is necessary to reduce the power consumption of a plurality of optical amplifiers when there is a difference in the required pumping power between the plurality of optical amplifiers; therefore, an optical amplifying apparatus according to an exemplary aspect of the invention includes a plurality of optical amplifying means for amplifying a plurality of optical signals, each of the plurality of optical amplifying means including a gain medium; a plurality of laser light generating means for generating a plurality of laser beams; at least one optical coupling means for coupling the plurality of laser beams variably in accordance with a coupling factor and outputting a plurality of excitation light beams, each of the plurality of excitation light beams exciting the gain medium; and controlling means for controlling the coupling factor and an output power of each of the plurality of laser light generating means.

A pulsed laser device includes a laser light source, an electro-optic modulator, a laser light source driver, an electro-optic modulator driver, and a controller to control the laser light source driver and the electro-optic modulator driver. The laser light source outputs pulsed laser light pulse-modulated by the laser light source driver. The electro-optic modulator outputs pulsed laser light obtained by causing the electro-optic modulator driver to pulse-modulate the pulsed laser light from the laser light source. The control unit controls the laser light source driver and the electro-optic modulator driver such that the electro-optic modulator turns on at least while the laser light source is on and the electro-optic modulator turns on at least once while the laser light source is off, thereby increasing a duty ratio of the pulse modulation for the electro-optic modulator relative to a duty ratio of the pulse modulation for the laser light source.

A laser apparatus includes a semiconductor laser element, a waveform calculation unit for calculating input waveform data, a driver circuit for supplying a drive current having a temporal waveform according to the input waveform data to the semiconductor laser element, an optical amplifier for amplifying laser light output from the semiconductor laser element, and a light waveform detection unit for detecting a waveform of laser light after the amplification output from the optical amplifier. The waveform calculation unit compares the waveform of the laser light after the amplification detected by the light waveform detection unit with a target waveform, adjusts a temporal waveform of the input waveform data, and brings the waveform of the laser light after the amplification close to the target waveform.

An EDFA may include an input photodiode configured to generate a control signal based on an input signal. The EDFA may include a blind stage configured to generate an amplified signal based on the control signal and the input signal. The EDFA may include a non-blind stage configured to generate an output signal based on the amplified signal within the blind stage, the control signal, and a feedback signal. The EDFA may include a filter configured to generate a filtered signal based on the output signal. The EDFA may include an output photodiode configured to generate the feedback signal based on the filtered signal. The EDFA may include an alarm device. A signal within the non-blind stage may be generated based on the feedback signal and the control signal. The alarm device may be configured to generate an alarm signal when the signal exceeds a threshold value.