Galvanometer controller and laser machining apparatus
AssigneeNEC Corporation
InventorsKazuaki Iwase, Akihiko Okano
Life of this patent
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Abstract
A galvanometer controller capable of control with stability and with immunity to changes with time and variation in environment temperature and having improved operability and expandability, and a laser machining apparatus having the galvanometer controller. The galvanometer controller comprises a correcting arrangement formed in a digital circuit, the correcting arrangement having a distortion correction section for correcting a working distortion of an optical unit including a lens, an orthogonality correction section for correcting the orthogonality between the two axes of the galvanometer, and a linearity correction section for correcting the linearity on each of the two axes.
Claims7
A galvanometer controlling apparatus comprising:
- a galvanometer for scanning a laser beam;
- an optical unit receiving a scanned laser beam from the galvanometer to lead the scanned laser beam for a workpiece;
- a position sensor for sensing a scanning position of the galvanometer to deliver a sensed signal;
- processing means receiving a digital command signal from a an upstream stage and the sensed signal from the position sensor for processing the digital command signal with the sensed signal to deliver a digital driving signal for the galvanometer;
- a D/A converter for converting the digital driving signal into an analog signal;
- an amplifier for amplifying the analog signal and supplying an amplified analog signal to the galvanometer, wherein the processing means includes a correction circuit for correcting scanning performed by the galvanometer, and the correction circuit is formed in a digital circuit;
- and
- a temperature detector to produce a temperature signal, wherein the correction circuit corrects an error due to characteristic change of the galvanometer depending on temperature change, in response to the temperature signal.
A laser machining apparatus comprising:
- a galvanometer for scanning a laser beam;
- a table;
- optical elements receiving a scanning laser beam from the galvanometer to lead the scanning laser beam for a workpiece on the table;
- a position sensor for sensing a scanning position of the galvanometer to deliver a sensed signal;
- a humidity detector for delivering a humidity signal;
- processing means receiving command data with the sensed signal and the humidity signal to deliver driving data for the galvanometer;
- a D/A converter for converting the driving data into an analog signal;
- and
- an amplifier for amplifying the analog signal and supplying an amplified analog signal to the galvanometer, wherein the processing means includes a correction circuit, and the correction circuit is formed in a digital circuit.
A galvanometer controlling apparatus comprising:
- a galvanometer for scanning a laser beam;
- an optical unit receiving a scanned laser beam from the galvanometer to lead the scanned laser beam for a workpiece;
- a position sensor for sensing a scanning position of the galvanometer to deliver a sensed signal;
- processing means receiving a digital command signal from an upstream stage and the sensed signal from the position sensor for processing the digital command signal with the sensed signal to deliver a digital driving signal for the galvanometer;
- a D/A converter for converting the digital driving signal into an analog signal;
- an amplifier for amplifying the analog signal and supplying an amplified analog signal to the galvanometer, wherein the processing means includes a correction circuit for correcting scanning performed by the galvanometer, and the correction circuit is formed in a digital circuit;
- and
- a humidity detector to produce a humidity signal, wherein the correction circuit corrects an error due to characteristic change of the galvanometer depending on humidity change, in response to the humidity signal.
A laser machining apparatus comprising:
- a galvanometer for scanning a laser beam;
- a table;
- optical elements receiving a scanning laser beam from the galvanometer to lead the scanning laser beam for a workpiece on the table;
- a position sensor for sensing a scanning position of the galvanometer to deliver a sensed signal;
- a temperature detector for delivering a temperature signal;
- processing means receiving command data with the sensed signal and the temperature signal to deliver driving data for the galvanometer;
- a D/A converter for converting the driving data into an analog signal;
- and
- an amplifier for amplifying the analog signal and supplying an amplified analog signal to the galvanometer, wherein the processing means includes a correction circuit and the correction circuit is formed in a digital circuit.
Dependencies are inferred from the claim text.