A laser oscillator of the present invention comprises: a semiconductor laser module; a first optical fiber for propagating a laser beam from the semiconductor laser module; and a first prism including a first input surface fusion-bonded to the first optical fiber and receiving the laser beam having been input from the first optical fiber, a first reflection surface for reflecting the laser beam having been input from the first input surface and for transmitting a stimulated Raman scattered beam, and a first output surface for outputting the laser beam having been reflected on the first reflection surface.

A fiber-based master optical power amplifier (MOPA) is configured to utilize a pump source that operates in pulse mode with the arrival time of the pump pulses coordinated with the arrival time of the input pulses. The width of the pump pulses is also controlled, thus providing a mechanism for controlling both the amount of pump energy injected into the fiber amplifier, as well as the overlap in time between the pump pulse and the seed pulse. As the pulse repetition interval (PRI) of the input seed pulse changes, the timing of the pump pulses and their width are also changed so that a constant gain environment is created within the amplifying medium, providing an essentially constant energy output pulse, regardless of differences in ASE generated during different PRIs.

An optical amplifying device according to the present invention includes: an optical propagation path including an optical amplifier for amplifying input light; an excitation light source for generating excitation light to excite the optical amplifier; first and second optical receivers detect the power of the input light in the optical propagation path before being amplified by the optical amplifier and the power of the light in the optical propagation path after being amplified by the optical amplifier; a third optical receiver for detecting the power of light having a traveling direction opposite to that of the input light amplified by the optical amplifier, in the optical propagation path; and a control unit for controlling the excitation light source on the basis of the light power detected by the first optical receiver, the light power detected by the second optical receiver, and the light power detected by the third optical receiver. This optical amplifying device can prevent a light surge without providing dummy light and without causing a service interruption.

Embodiments discussed herein refer to LiDAR systems and methods that enable substantially instantaneous power and frequency control over fiber lasers. The systems and methods can simultaneously control seed laser power and frequency and pump power and frequency to maintain relative constant ratios among each other to maintain a relatively constant excited state ion density of the fiber laser over time.

An optical amplifier assembly and a detection method capable of dynamically performing optical time-domain reflection detection. The detection method comprises obtaining signal light intensity detection signals from a first and second photodetectors and sending a control signal to an L-band Raman pump when it is determined that the signal light intensity in the second photodetector is lower than a first preset threshold, so that the L-band Raman pump enters into an optical time-domain reflection detection mode; sending a control signal to the L-band Raman pump when the signal light intensity in the second photodetector is greater than or equal the first preset threshold, so that the L-band Raman pump enters into an L-Band Raman optical fiber amplifier operation mode.

A burst logging system logs and transmits to a local or remote computing system event data related to errors in and or potential failures of laser system components. The system further provides for capturing data at different rates from different sensors, synchronization of data capture associated with system events and the possibility for aggregation of data from multiple systems, which can in turn be leveraged to predict and or remediate future system events.

Provided are a control method and system for a cascade hybrid amplifier, in which respective hybrid amplifiers in the cascade hybrid amplifier simultaneously start to implement a pump-starting process comprising: when the hybrid amplifier receives a request to start pumping, determining whether conditions are satisfied, if yes, determining stability of power of an input light of a Raman, starting pumping of an EDFA so that the EDFA enters into an APC operation mode; starting pumping of the Raman, and calculating a gain deviation according to the calculated input light powers before and after pump-starting of the Raman when no reflection alarm exists; and adjusting gain of the Raman according to the gain deviation, and switching to an AGC (automatic gain control) operation mode after the adjustment; and switching the EDFA to the AGC operation mode.

A system comprising a recirculating loop configured to store an electromagnetic wave signal, the recirculating loop comprising a transmission medium and a plurality of transceivers configured to introduce the electromagnetic wave signal into the transmission medium and retrieve the electromagnetic wave signal from the transmission medium, and a signal conditioning system comprising a plurality of signal conditioners coupled to the transmission medium, the plurality of signal conditioners configured to amplify or regenerate the electromagnetic wave signal traveling in the transmission medium, one or more pump laser sources, wherein at least one of the one or more pump laser sources is configured to provide a pump laser beam to at least two of the plurality of signal conditioners, and one or more control circuits for controlling the plurality of signal conditioners, wherein at least one of the one or more control circuits is configured to control and monitor at least two of the plurality of signal conditioners, is disclosed.

A system includes a master oscillator configured to generate a first optical beam and a beam controller configured to modify the first optical beam. The system also includes a PWG amplifier configured to receive the modified first optical beam and generate a second optical beam having a higher power than the first optical beam. The second optical beam has a power of at least about ten kilowatts. The PWG amplifier includes a single laser gain medium configured to generate the second optical beam. The system further includes a feedback loop configured to control the master oscillator, PWG amplifier, and beam controller. The feedback loop includes a laser controller. The laser controller may be configured to process wavefront information or power in bucket information associated with the second optical beam to control an adaptive optic or perform a back-propagation algorithm to provide wavefront correction at an output of the PWG amplifier.

A MOPA laser system that includes a seed laser configured to output pulsed laser light, an amplifier configured to receive and amplify the pulsed laser light emitted by the seed laser; and a pump laser configured to deliver a pump laser beam to both the seed laser and the amplifier and a variable attenuator configured to eliminate missing Q-switched pulses.