Periodical domain reversal crystal electro-optic Q-switched-based pulse optical fiber laser

Abstract

The invention discloses a periodical domain reversal crystal electro-optic Q-switched-based pulse optical fiber laser. The periodical domain reversal crystal electro-optic Q-switched-based pulse optical fiber laser is composed of a plurality of semiconductor laser pumping sources, a multimode optical fiber combiner, a high-reflection-rate optical fiber bragg grating, double-clad fiber, a left side optical fiber collimating mirror, a polarization splitting prism, periodical domain reversal crystal, a right side optical fiber collimating mirror and a low-reflection-rate optical fiber bragg grating. Direct-current voltage is applied to two lateral sides of the periodical domain reversal crystal so as to control polarization directions of lasers passing through the crystal and ensure that the crystal rotates according to an expected polarization state and to accordingly change a loss value in an optical fiber laser cavity. Voltage is periodically applied and removed, laser pulse output can be formed by the fiber laser, wherein pulse repeating frequency of the laser pulse output and voltage applying frequency of the laser pulse output are the same. A novel high-power pulse optical fiber laser which is simple and compact in structure, has good anti-optical-feedback ability, does not need a laser isolator on an output end, and is low in cost and very good in long-term stability can be acquired through the periodical domain reversal crystal electro-optic Q-switched-based pulse optical fiber laser.

Description

technical field [0001] The invention relates to a pulsed fiber laser, in particular to a pulsed fiber laser based on periodic domain inversion crystal electro-optic Q-switching. Background technique [0002] Fiber lasers are currently important lasers for high-power laser processing and laser biological applications. Compared with solid-state and gas lasers, fiber lasers have many advantages: smaller volume; large surface area to volume ratio, better heat dissipation, and no need for a huge water cooling system; better beam quality, and can get close to diffraction Extreme high-power laser output; high energy conversion efficiency; and high long-term working stability. [0003] Compared with the continuous working fiber laser, the pulse working fiber laser can obtain high peak laser power under the condition of lower average power, so it has a stronger ability to interact with light and matter. Based on this feature, pulsed fiber lasers with an average power of several wat...

AI Technical Summary

Problems solved by technology

However, the high-power fiber laser of the MOPA structure involves a process of multiple amplification of a low-power laser

Since the output power of the seed laser is too small, one or more stages of pre-amplification is required to meet the power requirements of the seed source. The structure is relatively complex and the cost is high.

Isolators must be installed between the fiber amplifiers at all levels and the seed laser, which significantly affects the reliability, volume and cost of the laser

In addition, MOPA-type pulsed fiber lasers are difficult to apply to occasions with strong laser feedback. Even if a high-isolation isolator is used at the laser output end, there is still the problem of laser self-excitation caused by the feedback laser, which affects the safety and reliability of the entire laser system itself. Work

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