Coaxial image system applied to LED laser cutting device

Abstract

The invention relates to a coaxial image system applied to an LED laser cutting device, comprising a coaxial LED point light source module, a 45-degree total reflection mirror, a wide-angle CCD module, a first 45-degree spectroscope, a small-vision field high-magnification upper CCD module, a second 45-degree spectroscope, a wavelength selection mirror, an LED ring light source, a focusing lens and a small-vision field high-magnification lower CCD module; the coaxial LED point light source module, the wide-angle CCD module and the small-vision field high-magnification upper CCD module are arrayed in parallel from top to bottom, the wavelength selection mirror is mounted between the CCD module and the focusing lens, the LED ring light source clings to the focusing lens which faces directly towards a workpiece, the small-vision field high-magnification lower CCD module is mounted below the workpiece. The invention realizes coaxial real-time image positioning function in the LED laser cutting device, combined usage of the wide-angle CCD and the small-vision field high-magnification upper CCD realizes micrometer-grade measurement accuracy, and the convenient switch of the small-vision field high-magnification upper CCD and the small-vision field high-magnification lower CCD meets the demands of front-cutting, back-cutting, surface coarsening and the cutting of back-aluminized wafer.

Description

technical field [0001] The invention relates to an optical image system, in particular to a coaxial image system applied to LED laser cutting equipment, and belongs to the technical field of laser precision processing. Background technique [0002] LED laser cutting equipment is a special laser equipment used for cutting GaN blue light LED wafers on sapphire substrates. Blue light LED wafers are usually grown on sapphire substrates by vapor phase deposition process GaN crystals, and finally on the wafers Several LED light-emitting units with independent light-emitting functions are formed by screen printing technology and electrodes. [0003] At present, blue LED wafer cutting equipment has been gradually upgraded from diamond knife cutting to laser cutting. With non-contact laser processing, the equipment must have precise positioning function. The reserved dicing width of general LED wafers is about 20-30um, even as narrow as 15um, while the laser processing affects the l...

AI Technical Summary

Problems solved by technology

Generally, blue LED wafers are cut in two ways: tangent and back-cut. The tangent is the laser cutting from the surface of the GaN luminescent material, and the back-cut is cutting from the surface of the sapphire substrate material. The dicing line is generally marked on the upper surface of the wafer, so In order to have tangential and back-cutting functions at the same time, the system needs to have the coaxial observation function of the upper image and the lower image. In addition, it is also a big challenge for the imaging system to cut the surface roughened and back-plated aluminum type wafers.

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