Research on Adjustable Ring-Mode Fiber Signal Combiner

Abstract

Nowadays, fiber laser has been widely used in industrial processing, especially in welding, cutting and other fields, and the appearance of adjustable ring-mode fiber laser improves effectively the quality of processing. In this paper, a (6 + 1) × 1 adjustable ring-mode fiber signal combiner is developed based on the technology of fiber cladding corrosion. The test results show that under the same injection condition, the beam quality transmitted through the central port of the combiner is degraded by only 8.3% compared with that transmitted through a single 50/250 μm fiber. It is proven to be feasible to maintain the beam quality of the (6 + 1) × 1 combiner by fiber corrosion technology. In order to improve the power of the central port of the (6 + 1) × 1 adjustable ring-mode combiner, a 3 × 1 fiber signal combiner and the central port of (6 + 1) × 1 combiner are cascaded. The output beam quality is M2 = 4.45 and the overall transmission efficiency is greater than 95%. This combiner can choose the mode of the output beam according to the actual application requirements, so as to achieve a better application effect.

Investigating changes in the electric field profiles of transverse modes in fibres due to bending

“…Development of optical fibre applications, including lasers and fibre amplifiers [8][9][10], control of mode instability [11][12][13][14][15], fibre sensors [16,17], material detection using evanescent fields [18], and telecommunication applications for data and information transmission [19][20][21], necessitates a comprehensive investigation into the behaviour of electric fields of fibre modes. Additionally, certain types of fibres with doughnut type or annular intensity distribution (Mode LP 02 ) can find utility in areas, such as optical tweezers [22] and scanning and treatment of internal surfaces of pipes [23,24]. Therefore, understanding the behaviour of modes and spatial distribution of electric fields within fibres, as well as the generation and enhancement of higher order modes, holds significant importance for the aforementioned applications.…”