Fiber coupling method for diode pumping solid-state laser

Abstract

The invention relates to direct fiber coupling technology with high laser outputting efficiency, in particular to a fiber coupling method for a diode pumping solid-state laser, which is characterized in that a laser output mirror of the diode pumping solid-state laser is a compound mirror (2); the compound mirror (2) is a plano-convex lens; the plane end of the compound mirror (2) is used as an output mirror of a resonant cavity and is plated with a plane end coating film (7) of a reflecting film of laser wavelength; the convex face end is plated with a convex face end coating film (8) of an anti-reflection film of the laser wavelength, and focuses transmission light; the convex face end of the compound mirror (2) is in light connection with a coupling fiber (3); and focal spot focused by an output ray beam of the laser is less than a fiber core, and a divergence angle is less than twice numerical aperture of the coupling fiber (3). Because the compound mirror replaces the output mirror and a coupling lens of a diode pumped solid-state laser, the method greatly simplifies the structure, and makes the operation simple and convenient. The use of the compound mirror solves the problem that the coupling lens cannot be in close proximity to the output mirror, achieves the zero distance of theory limit, reduces the requirements on the numerical aperture and effective clear aperture and facilitates obtaining of high fiber coupling efficiency.

Description

Technical field [0001] The invention relates to a direct fiber coupling technology for high-efficiency laser output, in particular to a diode-pumped solid-state laser fiber coupling method. technical background [0002] High-power diode-pumped solid-state lasers are widely used in military, industrial and medical fields. If the output laser energy of DPL is coupled into the fiber, the operation of such a laser with a certain volume and weight will change. In order to greatly improve the flexibility of use and realize flexible three-dimensional laser processing for the operation of the coupled fiber with a certain flexibility, this technology can be applied to the fields of industrial cutting, welding, surface treatment, etc., greatly simplifying the design difficulty of the processing system and cost. The fiber coupling technology of DPL output laser has important use value. [0003] The method of fiber coupling for diode-pumped solid-state lasers is usually: at the rear end of t...

AI Technical Summary

Problems solved by technology

[0004] However, there are certain defects in this fiber coupling method: first, the output beam of DPL is a Gaussian beam. If the output mirror is a flat mirror, the beam waist is theoretically located on the output mirror. Therefore, the only way to make the coupling lens as close as possible to the output mirror is to In order to make the beam width and divergence angle of the coupling lens as small as possible, and reduce the requirements for the numerical aperture and effective clear aperture of the coupling lens, but due to structural limitations, the coupling lens and the output mirror cannot be very close; secondly, in practice During the operation, it is necessary to adjust the spatial position and angle of the coupling lens and optical fiber to the output beam at the same time, which is very difficult to operate

The existence of the coupling lens increases the complexity of the adjustment structure

Direct fiber coupling can avoid the above problems, but it is difficult to achieve high coupling efficiency

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