Abstract:
The disclosed method and apparatus for stabilizing a mode-locked regime of a fiber ring oscillator based on a NPR include tapping a portion of light, which has a broad spectral bandwidth, from a fiber ring resonator into at least first and second control channels. The control channels are configured to guide respective first and second fractions of the tapped portion. One of the control channels is provided with a bandpass filter operative to extract a region from the broad spectral bandwidth. The fractions with respective full spectral bandwidth and region thereof are then evaluated in a central processing unit which is operable to generate a control signal if a predetermined criterion is not met. The control signal is received by one or more polarization controller units operative to dynamically modulate a state of polarization of light in the fiber ring resonator until the evaluation meets the predetermined criterion.
Abstract:
Устройство относится к области квантовой электроники. Полностью волоконный лазер со сверхкороткой длительностью импульса содержит лазер накачки, модуль ввода излучения лазера накачки в волокно, легированное редкоземельным элементом волокно, разветвитель, контроллеры поляризации, волоконные поляризаторы с взаимно перпендикулярными направлениями поляризации, акустооптический модулятор, установленный непосредственно на оптическое волокно между волоконными поляризаторами, частота акустооптического модулятора равна собственной частоте кольцевого волоконного резонатора. Техническим результатом изобретения является создание полностью волоконного лазера со сверхкороткой длительностью импульса.
Abstract:
Methods, systems and apparatus are disclosed for delivery of pulsed treatment radiation by employing a pump radiation source generating picosecond pulses at a first wavelength, and a frequency-shifting resonator having a lasing medium and resonant cavity configured to receive the picosecond pulses from the pump source at the first wavelength and to emit radiation at a second wavelength in response thereto, wherein the resonant cavity of the frequency-shifting resonator has a round trip time shorter than the duration of the picosecond pulses generated by the pump radiation source. Methods, systems and apparatus are also disclosed for providing beam uniformity and a sub-harmonic resonator.
Abstract:
Aspects of the disclosure relate generally to a circuit (100) for sustaining an radio frequency (RF) modulated optical signal. The circuit may comprise a self injection locking component (107) having a fiber optic delay line (130) over which a portion of the optical signal propagates. The circuit may also comprise a self phase locked loop component (109) having at least two fiber optic cables (120, 140) having different lengths and over which another portion of the optical signal propagates and a phase detector (150) coupled to the at least two fiber optic cables and configured to determine a phase difference between the signals propagating over one of the respective fiber optic cables. The circuit may further comprise a voltage controlled oscillator (110) configured to generate a stable oscillating signal in response to signals generated by each of the self injection locking and self phase locked loop components, the stable oscillating signal being configured to sustain the optical signal.
Abstract:
This invention provides a solution for operating a mode-locking and cavity dumping laser apparatus using single electro-optical switch or modulator (2), such as a Pockels cell, without the need of multiplexing between two sources of voltage. The complex waveform of electrical signal, which controls the Pockels Cell (2) is achieved by employing the phenomena, called LC circuit ringing, where LC circuit is formed from an inductive element and a capacitor, where the Pockels Cell works as a capacitor itself. The ringing frequency should be calculated such that the period of oscillations is preferably two times longer than the round-trip time of a light pulse inside the optical cavity. As a result, optical losses are created inside the cavity with a period, which coincides with the travel of a light pulse, thus the pulse build-up is consistent and stable.
Abstract:
A control system for improving and stabilizing Fourier domain mode locking (FDML) operation. The control system may also provide regulation of FDML operational parameters such as filter tuning, laser gain, polarization, polarization chromaticity, elliptical polarization retardance, and/or dispersion. The control system may be located internal to or external from the FDML laser cavity.
Abstract:
A control system for improving and stabilizing Fourier domain mode locking (FDML) operation. The control system may also provide regulation of FDML operational parameters such as filter tuning, laser gain, polarization, polarization chromaticity, elliptical polarization retardance, and/or dispersion. The control system may be located internal to or external from the FDML laser cavity.
Abstract:
This application describes coupled and non-coupled opto-electronic oscillators with enhanced performance. Coupled OEOs implement a dispersion compensation mechanism to reduce dispersion-induced optical loss, a polarization control mechanism to reduce polarization-dependent optical loss, or a combination of the dispersion compensation mechanism and the polarization control mechanism to enhance the oscillator performance.
Abstract:
Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally- occurring (e g, birthmarks), as well as artificial (e g, tattoos). The laser energy may be generated with an apparatus havin resonator (fig 2) with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein an electro-optical device (e g, a Pockels cell) positioned along the optical axis of the resonator.