Patent ID: 8941030
Filing Date: 2015-01-27
Classification: B23K,B41J

Abstract:
1. A laser processing apparatus comprising: a chuck table for holding a workpiece; laser beam applying means for applying a pulsed laser beam having a transmission wavelength to said workpiece held on said chuck table; feeding means for relatively moving said chuck table and said laser beam applying means in a feeding direction (X direction); X position detecting means for detecting the X position of said chuck table fed by said feeding means; and control means for controlling said laser beam applying means according to a detection signal from said X position detecting means; said laser beam applying means including pulsed laser beam oscillating means for oscillating said pulsed laser beam, focusing means having a focusing lens for focusing said pulsed laser beam oscillated by said pulsed laser beam oscillating means and applying said pulsed laser beam to said workpiece held on said chuck table, and a piezoelectric motor for displacing said focusing means in a direction inclined at a predetermined angle (α) with respect to the optical axis of said focusing lens (Z direction); said control means controlling the frequency and voltage of an RF current to be applied to said piezoelectric motor in relation to the repetition frequency of said pulsed laser beam to move said focusing means in said X direction by Δx and in said Z direction by Δz in feeding said chuck table in said X direction, thereby displacing the focal point of said pulsed laser beam to be focused by said focusing lens in the thickness direction of a predetermined area of said workpiece held on said chuck table.