Continuously-tunable single-frequency optical fiber laser

Abstract

The invention provides a continuously-tunable single-frequency optical fiber laser. The continuously-tunable single-frequency optical fiber laser includes a multi-component glass optical fiber, a broadband optical fiber grating, a narrowband optical fiber grating, a wavelength division multiplexer, a pumping source, an optical isolator and a laser frequency tunable device, wherein the laser frequency tunable device is composed of a first thermoelectric cooler (TEC) and a second thermoelectric cooler (TEC) which are fixed at different positions in a single-frequency laser resonant cavity. According to the continuously-tunable single-frequency optical fiber laser of the invention, a multi-component glass optical fiber-based short linear resonant cavity and an all-optical fiber optical path structure are utilized, such that the laser can perform single-frequency operation stably and reliably; two thermoelectric coolers (TEC), namely double-temperature control tuning technology, are utilized to adjust and change the temperature distribution inside the cavity widely and regionally, and a temperature effect will cause constant changes of the length of the resonant cavity and the reflection spectrum of the narrowband optical fiber grating respectively, and therefore, the frequency of the laser can be tuned continuously and widely in real time. Thus, the continuously-tunable single-frequency optical fiber laser is advantageous in simple structure, low cost and high repeatability.

Description

technical field [0001] The invention relates to a fiber laser, in particular to a single-frequency, continuous tunable fiber laser using thermoelectric cooler TEC temperature control as a frequency tunable device. Background technique [0002] Tunable single-frequency fiber laser is a very important laser light source. It has a wide range of application requirements in the fields of fiber optic sensing, laser ranging, laser speed radar, and high-precision spectroscopy. Single-frequency fiber laser refers to the output in the form of a single longitudinal mode (single frequency) of vibration in the laser resonator, which is characterized by a very narrow laser spectral linewidth, up to 10 -8 nm, which is several orders of magnitude higher than the commonly used narrow-linewidth DFB semiconductor lasers. In addition, it also has the characteristics of low noise and excellent coherence, so it has attracted great attention. [0003] The current research work on tunable single-f...

AI Technical Summary

Problems solved by technology

[0005] Patents related to single-frequency lasers include: (1) Shanxi University applied for a patent on single-frequency tunable lasers in 2005 [Publication No.: CN1770574A], which uses neodymium-doped solid crystal gain media and electro-optic crystals to form laser resonators, realizing The laser frequency is tunable, but the required single-frequency laser does not have all-fiber and wide linewidth

(2) In 2011, IPG Corporation of the United States applied for the patent of high-power single-frequency fiber laser [publication number: US7903696B2], which uses two ultra-short single-frequency resonators to output low-power single-frequency laser signals, and passes through two-stage fiber amplifiers respectively. Performs laser power amplification, but requires fiber lasers that do not have frequency tunable features

Images