Various implementations of the invention compensate for “phase wandering” in tunable laser sources. Phase wandering may negatively impact a performance of a lidar system that employ such laser sources, typically by reducing a coherence length/range of the lidar system, an effective bandwidth of the lidar system, a sensitivity of the lidar system, etc. Some implementations of the invention compensate for phase wandering near the laser source and before the output of the laser is directed toward a target. Some implementations of the invention compensate for phase wandering in the target signal (i.e., the output of the laser that is incident on and reflected back from the target). Some implementations of the invention compensate for phase wandering at the laser source and in the target signal.

A method of controlling an optical transmitter includes steps of amplifying, by an EDFA, a main signal output from an optical modulator, attenuating and outputting, by a VOA, the main signal amplified and output by the EDFA, and maintaining an output power of the main signal output from the VOA at a predetermined value, suspending the phase modulation in the optical modulator to output continuous wave light from the optical modulator, disabling feedback control of the VOA that is performed by the VOA controller and maintaining a constant control signal of the VOA, disabling feedback control of a pump laser that is performed by a pump laser controller, and controlling the pump laser to modulate an intensity of the excitation light and generate an auxiliary signal having a cycle longer than a cycle of the main signal.

A tip/tilt/piston (“TTP”) MEMS MMA is used to provide coherent beam combination (CBC) such that the combined beam behaves as if it were emitted from a single aperture laser, but with higher brightness than can be obtained from an individual laser. Piston actuation of the mirrors is used to adjust the phase of individual amplified laser beams and maintain a zero phase difference across all of the amplified laser beams. Tip/Tilt actuation of the mirrors is used to steer the phase-adjusted amplified laser beams to form a coherent output laser beam. Additional TTP actuation can be used to oversimple and superimpose Adaptive Optics correction or focusing/defocusing on the beam, A multi-spectral system may be implemented with a common MEMS MMA to produce a spectrally beam combined, multi-channel coherent laser beam.

Systems and methods described herein are directed to optical light sources, such as an external cavity laser (ECL) with an active phase shifter. The system may include control circuity for controlling one or more parameters associated with the active phase shifter. The phase shifter may be a p-i-n phase shifter. The control circuitry may cause variation in a refractive index associated with the phase shifter, thereby varying a lasing frequency of the ECL. The ECL may be configured to operate as a light source for a light detection and ranging (LIDAR) system based on generating frequency modulated light signals. In some embodiments, the ECL may generate an output LIDAR signal with alternating segments of increasing and decreasing chirp frequencies. The ECL may exhibit increased stability and improved chirp linearities with less dependence on ambient temperature fluctuations.

A laser beam positioning system of a laser-based specimen processing system produces at beam positioner stage, from a fully fiber-coupled optics phased array laser beam steering system, a steered laser input beam. System directs beam through one or more other beam positioner stages to form a processing laser beam that processes target features of a workpiece mounted on a support.

A device and a method for producing a patterned functional coating on a first curved glass layer, the device including a support for holding the first curved glass layer, at least one laser, and a guidance unit, provided for guiding the beam of the laser over the functional coating, such that parts of the functional coating are removed in order to pattern the functional coating.

A phase control system for controlling the relative phase (φ) of two laser beams of a laser system, which are to be coherently combined, is disclosed that enables providing a phase-controlled sum laser beam. An optical system of the phase control system includes a beam input for receiving a measuring portion of two collinear coherent laser beams, which are superimposed to form a sum laser beam, and provides measuring beams or measuring beam regions, which are used with associated photodetectors for outputting photodetector signals. For determining the relative phase from the photodetector signals, the phase control system has an evaluation device and a delay device for being inserted into the beam path of at least one of the two laser beams. The optical system is configured such that the measuring beams or measuring beam regions are related to different phase offsets.

A femtosecond laser multimodality molecular imaging system includes a near-infrared pulse generation device for providing near-infrared pulses with a central wavelength of 1010 nm to 1100 nm and a spectral width of less than 25 nm. The near-infrared pulses can excite an optical medium with strong nonlinearity to generate the femtosecond laser pulses with ultra-wide spectrum. A pulse measurement compression and control module measures and compensates the accumulated dispersion of the femtosecond laser pulses arriving at the tissue sample, so as to eliminate the “time domain broadening” effect as much as possible. The obtained shortest pulses can interact with the tissue sample to generate spectral signals from different modalities, thus providing a variety of nonlinear molecular image modalities.

A laser system including: A. a laser apparatus configured to output a pulse laser beam; B. an optical pulse stretcher including a delay optical path for expanding a pulse width of the pulse laser beam; and C. a phase optical element included in the delay optical path and having a function of spatially and randomly shifting a phase of the pulse laser beam. The phase optical element includes a plurality of types of cells providing different amounts of phase shift to the pulse laser beam and arranged irregularly in any direction.

Apparatus for modelocking a fiber laser cavity includes two variable retarder assemblies and a polarizing element. The variable retarder assemblies each have two electronically addressable elements and one fixed element. The first variable retarder assembly prepares a polarization state suitable for NPE modelocking to be launched into the fiber, and the second variable retarder assembly controls the polarization state after exiting the fiber, before being incident on the polarizing element. A control system controls the electronically addressable phase retarders in order to create and modify conditions for modelocking the fiber laser.