Optical fiber for optical laser, its manufacuture method and optical laser

Abstract

The purpose of the invention is providing an optical fiber for an optical fiber laser for inhibiting the temperature ascending for the optical fiber and obtaining the larger power for the laser and the manufacturing method and the optical fiber laser. The optical fiber laser of the invention has a rare-earth core (2) with the rare-earth elements and the covering (3) added with the rare-earth core; the incentive light (Le) is emitted from the end part of the covering (3); the incentive rear-earth element outputs the laser vibrating light (L) by the large power; in addition, the rare-earth core (2) is divided into several core areas (2a, 2b, ...... 2n-1, 2n) along the length directions; the adding concentration of the rare-earth elements added at the several core areas (2a, 2b, ......2n-1, 2n) are different.

Description

technical field [0001] The present invention relates to a high-power optical fiber for optical fiber laser equipped with a rare earth-doped core and cladding, a manufacturing method thereof, and an optical fiber laser. Background technique [0002] In order to use it in laser processing, medical treatment, etc., it is necessary to develop a more powerful and inexpensive light source. In response to these needs, fiber lasers have attracted attention because they can efficiently and easily extract high-quality laser light. [0003] As the fiber used for such high power fiber lasers there are Figure 9 Optical fiber 91 is shown. This optical fiber 91 is a double clad including a core 92 doped with a rare earth element (Yb, Er, Er / Yb, Tm, Nd, etc.) and a cladding 93 composed of a first cladding 93a and a second cladding 93b. optical fiber. In addition, although not shown, a coating layer made of ultraviolet curable resin or the like is provided on the outer periphery of the s...

AI Technical Summary

Problems solved by technology

[0007] However, in the existing optical fiber 91, when a Yb-added (doped) core is used as the core 92, the light / light conversion efficiency of the laser oscillation light L9 relative to the excitation light Le9 is about 80%, and about 20% of the energy becomes become hot

[0008] Therefore, in the existing optical fiber 91, as the power of the fiber laser increases, the temperature of the optical fiber 91 rises, especially near the incident end of the optical fiber 91. The temperature rise is large, and the cladding layer of the optical fiber 91 may be damaged. The problem that the output of the laser is limited

[0009] In addition, as limiting factors for high-power fiber lasers, there are various problems such as fiber nonlinearity, fiber damage, and excitation methods.

That is to say, in the existing optical fiber 91, as the power of the fiber laser increases, a large excitation optical power is required, resulting in excess energy density in the double-clad optical fiber, resulting in heat generation, fiber nonlinearity, fiber damage, etc. question

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