Laser device of long-focal depth and small-focal spot lens focusing system

Abstract

The invention discloses a laser device of a long-focal depth and small-focal spot lens focusing system. The laser device includes a laser source, laser, a first surface, a first optical element, a second surface, a third surface, a second optical element, a fourth surface, an image point imaged by the first optical element, an image point imaged by a lens group, and an optical screen; the laser source emits the laser; the lens group includes the first optical element and the second optical element arranged on the optical path of the laser; the first optical element includes the first surface and the second surface; and the second optical element includes the third surface and the fourth surface. The laser device of the invention has the advantages of simple structure, low manufacturing cost and small size, and can satisfy requirements for miniaturization; and the materials and positions of the optical elements in the laser device are properly set, and related parameters of the laser source are properly selected, and therefore, the system device can further have the advantages of long focal depth, small focal spot and low requirements for workpiece flatness.

Description

technical field [0001] The invention relates to the field of optical system design and the field of laser processing technology, in particular to a long focal depth and small focal spot focusing system for realizing a laser drilling device. Background technique [0002] Since the advent of lasers in 1960, the application of lasers in processing has continued to expand, especially in laser drilling, cutting, and photolithography. In the laser drilling device, the size and depth of focus of the beam after focusing are the key to determining the drilling accuracy. Since the resolution R is inversely proportional to λ / NA (λ is the laser wavelength and NA is the numerical aperture), the DOF (Depth of Focus) is proportional to λ / NA 2 , so as the resolution (as assessed by the laser spot size) increases, the depth of focus decreases. The decrease of the depth of focus will directly affect the surface quality of the processed object, such as the decrease of sharpness and the incre...

AI Technical Summary

Problems solved by technology

However, this technology requires broadband laser or multi-wavelength laser, resulting in high cost

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