US 12,403,548 B2
Laser processing apparatus and laser processing method
Jun Yokoyama, Osaka (JP); Takashi Urashima, Osaka (JP); and Yohei Takechi, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
Filed on Jul. 19, 2021, as Appl. No. 17/378,815.
Claims priority of application No. 2020-138677 (JP), filed on Aug. 19, 2020; and application No. 2020-140886 (JP), filed on Aug. 24, 2020.
Prior Publication US 2022/0055147 A1, Feb. 24, 2022
Int. Cl. B23K 26/03 (2006.01); B23K 26/082 (2014.01); G01B 11/00 (2006.01); G02B 19/00 (2006.01); G02B 26/08 (2006.01); G02B 26/10 (2006.01)
CPC B23K 26/032 (2013.01) [B23K 26/082 (2015.10); G01B 11/002 (2013.01); G02B 19/0014 (2013.01); G02B 19/009 (2013.01); G02B 26/0816 (2013.01); G02B 26/105 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A laser processing apparatus comprising:
a laser oscillator configured to oscillate processing laser light to be incident on a processing point on a processing surface of a workpiece;
a measurement light inlet configured to introduce measurement light to be incident on the processing point;
a coupling mirror configured to deflect or transmit the processing laser light and measurement light toward the processing point;
a measurement light deflection unit installed between the measurement light inlet and the coupling mirror and configured to change an incident angle of the measurement light on the coupling mirror by changing an optical axis direction of the measurement light;
a lens configured to concentrate the processing laser light and the measurement light on the processing point;
a controller configured to control the laser oscillator and the measurement light deflection unit;
a measurement processor configured to measure a depth of a keyhole generated at the processing point by the processing laser light by using an optical interference signal based on an interference generated by an optical path difference between the measurement light reflected at the processing point and reference light; and
a beam position measurement unit configured to measure positions of the processing laser light and the measurement light,
wherein the measurement light deflection unit includes:
(i) a parabolic mirror or a micro electro mechanical systems (MEMS) mirror fixed between the measurement light inlet and the coupling mirror and a movement stage configured to move the measurement light inlet, or (ii) a movement stage configured to move the measurement light inlet and a collimating lens.