摘要:
A method for controlling emission of optical pulses from a passive Q-switched laser apparatus comprises pumping a gain medium of a passive Q-switched laser apparatus for the emission of a plurality of Q-switched optical pulses from the laser apparatus. The method may further comprise pumping the gain medium so as to maintain an optical gain provided by the gain medium above an unpumped optical gain level for the duration of a time period from emission of one Q-switched optical pulse to emission of a subsequent Q-switched optical pulse. The method may further comprise varying a rate of pumping of the gain medium between emission of the one Q-switched optical pulse and emission of the subsequent Q-switched optical pulse so as to control the temporal separation between the one Q-switched optical pulse and the subsequent Q-switched optical pulse. The gain medium may comprise a solid state gain medium. The method may comprise optically pumping the gain medium.
摘要:
L'invention a pour objet un système de mise en phase de sources laser à configuration périodique, qui comprend : - des moyens pour collimater et diriger les faisceaux issus des sources sur un élément optique diffractif de recombinaison (1) à réseau de phase périodique, avec un angle d'incidence différent d'un faisceau à l'autre, ces angles d'incidence étant déterminés en fonction de la période du réseau, - des moyens de contrôle des phases desdites sources à partir d'un signal de contre-réaction issu des faisceaux recombinés, - des moyens (5) de prélèvement d'une fraction (12) des faisceaux recombinés, - sur le trajet de cette fraction des faisceaux, une lentille de Fourier (6), avec l'élément optique diffractif de recombinaison (1) dans son plan objet, - une matrice de détecteurs (7) dans le plan image de la lentille de Fourier (6), apte à détecter des distributions d'intensité, - des moyens (8) de calcul du signal de contre-réaction à partir de ces distributions d'intensité.
摘要:
A pulsed fiber laser oscillator comprising in succession: a pumping source (10) for providing pumping energy at a first wavelength to a multimode optical fiber; a first Bragg grating optical filter (11 ) reflecting a second wavelength and transparent to said first wavelength; an active optical fiber (20) having a predefined wavelength which emits radiation at said second wavelength; a switch (14) arranged to periodically interrupt said second wavelength to provide a pulsed laser beam; and a second Bragg grating optical filter (15) partially reflecting said second wavelength; characterized by comprising, following said active optical fiber (20), a reflector (21 ) of said first wavelength, such that said pumping energy undergoes two passages within said active optical fiber (20); said predefined wavelength being determined such that the absorption of said pumping energy at said first wavelength within said active optical fiber (20) is greater than 80% after undergoing said two passages.
摘要:
Systems and methods provide laser pulse equalization at different pulse repetition frequencies (PRFs). After initially pumping a lasing medium from a first pumping level to a peak pumping level, a controller may cause a pump source to continue pumping the lasing medium according to a pulse equalization pumping curve. The equalization pumping curve may be determined based on testing laser pulse parameters at different PRFs to achieve an optimal equalization result of the pulse parameters. The optimization metric used to evaluate various equalization pumping curves may include a consistency of the pulse energy level, peak power level, and/or pulse width of the laser under different PRFs. The equalization pumping curve may be a descending curve from the peak pumping level to the first pumping level. The equalization pumping curve may be a linearly declining curve, a substantially exponentially declining curve, a parametrically declining curve, or any other curve type.
摘要:
The present invention relates to an all-fiber pulsed fiber laser module for obtaining high- definition laser pulses with a convenient method, and an all- fiber pulsed fiber laser module is provided, comprising a resonant cavity having a laser oscillatory fiber between a first FBG and a second FBG in which the reflectivity of the first FBG is larger than the reflectivity of the second FBG; a first pumping light source for providing a first pumping light to obtain oscillatory laser by exciting the laser oscillatory fiber; and an all-fiber variable optical attenuator for inducing a periodic Q-switching of the oscillatory laser or the first pumping light to generate pulsed laser.
摘要:
The laser system(100) comprises an oscillator (110), the active material responsive to first laser radiation such that in response to the first laser radiation, the active material emits photons, a diode pump (115) comprising at least one laser diode array arranged to provide the first laser radiation to the active material to excite the active material to emit the photons, and a pulse generator (330) for generating first pulsed laser radiation at a first wavelength and having a micro-macro pulse structure, and a conversion stage (120) coupled to the oscillator stage to receive the first pulsed laser radiation (117), the conversion stage configured to amplify the first pulsed laser radiation and convert at least some of the amplified pulsed laser radiation (125) to a second wavelength, the conversion stage providing second pulsed laser radiation at the second wavelength and having the micro-macro pulse structure, wherein the micro-macro pulse structure includes a plurality of macro-pulses having a duration (T2) on the millisecond scale, each of the plurality of macro-pulses comprising the envelope of a plurality of micro-pulses having a pulse duration (T3) on the picosecond scale.
摘要:
A broadband light source includes one or more laser diodes that are capable of generating a pump signal having a wavelength shorter than 2.5 microns, a pulse width of at least 100 picoseconds and a pump optical spectral width. The light source also includes one or more optical amplifiers that are coupled to the pump signal and are capable of amplifying the pump signal to a peak power of at least 500W. The light source further includes a first fiber that is coupled to the one or more optical amplifiers. The first fiber including an anomalous group-velocity dispersion regime and a modulational instability mechanism that operates to modulate the pump signal. In one particular embodiment, the pump signal wavelength resides in the anomalous group- velocity dispersion regime of the first fiber and where different intensities in the pump signal can cause relative motion between different parts of the modulated pump signal produced through modulational instability in the first fiber. The light source also including a nonlinear element that is coupled to the first fiber that is capable of broadening the pump optical spectral width to at least 100nm through a nonlinear effect in the nonlinear element.