Laser working method and an apparatus therefor

A laser working apparatus in which a laser beam generated from a laser oscillator is transmitted to a working head having a condensing lens, and the working head is moved to subject a workpiece to laser working, comprising:

• a single lens located between the laser oscillator and the condensing lens of the working head, to change a laser propagation characteristic in a laser propagation path between said laser oscillator and the condensing lens of the working head;
• first drive means for moving said working head to subject said workpiece to laser working;
• second drive means for moving said single lens;
• distance determining means for determining a distance of the laser propagation path between said laser oscillator and a position of the moving working head moved by said first drive means;
• lens position setting means for setting a position of said single lens in accordance with the distance determined by said distance determining means;
• and
• drive control means for controlling said second drive means to move said single lens to the position set by said lens position setting means.

A laser working apparatus for transmitting a laser beam generated from a laser oscillator to a working head including a condensing lens, said working head being moved to subject a workpiece to laser working, comprising:

• a condensing optical component, including a reflector and a curved reflector, located between said laser oscillator and said condensing lens of said working head to change a laser propagation characteristic in a laser propagation path from said laser oscillator to said condensing lens of said working head;
• drive means for moving said condensing optical component;
• distance determining means for determining a distance of said laser propagation path between said laser oscillator and said condensing lens of said working head;
• condensing optical component position setting means for setting a position of said condensing optical component in accordance with said distance determined by said distance determining means;
• and
• drive control means for controlling said drive means to move said condensing optical component to said position set by said condensing optical component position setting means.