DETECTION METHOD FOR REFLECTED LIGHT AND LASER PROCESSING HEAD

摘要

PROBLEM TO BE SOLVED: To provide a reflected-light detection method which enables a ratio of the maximum value to the minimum value of an A/D count value of an amount of light in reflected light from a laser processing position to be kept low and a laser processing head.SOLUTION: A reflected-light detection method for detecting reflected light RLB from a laser processing position WP when laser processing is to be performed by condensing laser light oscillated from a laser oscillator with a condenser lens that a laser processing head has to irradiate a workpiece enables reflected light in a wavelength band with a large amount of reflected light in reflected light RLB from a laser processing position WP to be shielded by a filter 7 that the laser processing head 1 has to make a reflected-light detector 9 that the laser processing head 1 has detect reflected light in a wavelength band with a small amount of reflected light having penetrated through the filter 7. A range of wavelengths of reflected light that the filter 7 transmits is a range of about 550 nm-811 nm that is a range which keeps the ratio of maximum value/minimum value of an A/D count value of an amount of visible light to 3 or less.SELECTED DRAWING: Figure 1