US 11,806,812 B2
Laser machining device
Masatoshi Nishio, Osaka (JP); Jingbo Wang, Hyogo (JP); Hitoshi Nishimura, Osaka (JP); and Motoki Morioka, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
Filed on Jan. 29, 2021, as Appl. No. 17/162,510.
Application 17/162,510 is a continuation of application No. PCT/JP2019/007600, filed on Feb. 27, 2019.
Claims priority of application No. 2018-148541 (JP), filed on Aug. 7, 2018.
Prior Publication US 2021/0146481 A1, May 20, 2021
Int. Cl. B23K 26/70 (2014.01); B23K 26/082 (2014.01); B23K 26/06 (2014.01); B23K 26/38 (2014.01)
CPC B23K 26/705 (2015.10) [B23K 26/0648 (2013.01); B23K 26/082 (2015.10); B23K 26/38 (2013.01); B23K 26/707 (2015.10)] 8 Claims
OG exemplary drawing
 
1. A laser machining device configured to emit a laser beam, the laser machining device comprising:
a collimate lens;
a long-focus lens configured to focus the laser beam which has passed through the collimate lens;
a first parallel plate disposed closer to an outgoing side than the long-focus lens and inclined relative to an optical axis at an angle;
a second parallel plate disposed closer to an incoming side than the first parallel plate;
a first detector configured to detect a first output of the laser beam which has been reflected from an exit end surface of the first parallel plate;
a second detector configured to detect a second output of the laser beam which has been reflected from an entrance end surface of the first parallel plate;
a third detector configured to detect a third output of the laser beam which has been reflected from an entrance end surface of the second parallel plate; and
a controller configured to calculate an amount of a focal shift of the second parallel plate based on a detection value indicating the second output of the laser beam detected by the second detector and a detection value indicating the third output of the laser beam detected by the third detector, the amount of the focal shift of the second parallel plate being generated by distortion of the second parallel plate,
wherein the first parallel plate is disposed to keep contamination from adhering to the second parallel plate.