Laser system having fault diagnosis function

Patent metadata

Field	Value
Publication number	US-9685758-B2
Application number	US-201615346185-A
Country	US
Kind code	B2
Filing date	Nov 8, 2016
Priority date	Nov 9, 2015
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

A laser system having an automatic diagnosis function enabling a plurality of laser diodes to be diagnosed for faults in a short time.
The laser system includes a judging part judging the presence of a fault or deterioration of a component of the laser system. The judging part is configured to judge the presence of a fault or deterioration of a component of the laser system based on the results of detection of a first photodetection part and second photodetection part when successively driving a plurality of laser diode module groups included in an individual laser oscillation unit so that the mutual drive times do not overlap simultaneously for at least two laser oscillation units among a plurality of laser oscillation units.

First claim

The invention claimed is:

1. A laser system comprising a plurality of laser oscillation units and configured to combine laser light emitted from the plurality of laser oscillation units for emission to the outside, wherein
each of the laser oscillation units includes
a plurality of laser diode module groups each including at least one laser diode module acting as a light source or excitation light source,
a first optical coupling part combining the laser light emitted from the plurality of laser diode module groups, and
at least one first photodetection part detecting the output power of laser light combined by the first optical coupling part,
the laser system comprises
a second optical coupling part combining the laser light emitted from the plurality of laser oscillation units,
at least one second photodetection part detecting the output of the laser light combined by the second optical coupling part,
power supply parts that are able to supply driving current to the plurality of laser diode module groups independently from each other,
a recording part recording optical output characteristics showing the relationship between driving current and output power of laser light at each of the laser diode module groups,
a control part commanding driving conditions showing the driving current to be supplied to each of the laser diode module groups to the power supply parts,
a judging part judging any fault or deterioration of the components of the laser system, and
an operating part used for setting the driving conditions, and
the judging part is configured to judge, simultaneously for at least two laser oscillation units among the plurality of laser oscillation units, any fault or deterioration of the components of the laser system based on the results of detection of the first photodetection part and the second photodetection part when successively driving the plurality of laser diode module groups included in each of the laser oscillation units so that their drive times do not overlap.

2. The laser system according to claim 1 , wherein the control part is configured to set the driving conditions so that the driving current supplied to each of the laser diode module groups changes continuously or in stages when the judgment by the judging part is performed.

3. The laser system according to claim 1 , wherein the control part is configured to set the driving conditions so that a drive cycle for successively driving the plurality of laser diode module groups included in each of the laser oscillation units so that their drive times do not overlap is performed several times while changing the driving current supplied to each of the laser diode module groups when judgment by the judging part is performed.

4. The laser system according to claim 1 , wherein when judgment by the judging part is performed, a laser beam emitting end of the laser system is configured to move to a retracted position so that the laser beam emitted from the laser system to the outside is absorbed at a light absorbing part.

5. The laser system according to claim 4 , wherein the light absorbing part includes a third photodetection part measuring the optical output of laser beam incident on the light absorbing part.

6. The laser system according to claim 1 , wherein each laser oscillation unit comprises a plurality of said first photodetection parts.

7. The laser system according to claim 1 , comprising at least two said second photodetection parts.

8. The laser system according to claim 1 , wherein
each of the laser oscillation units further comprises
a cooling plate cooling the at least one laser diode module and
a temperature detector detecting the temperature of the cooling plate, and
the judging part is configured to judge any fault or deterioration of the components of the laser system based further on the results of detection of the temperature detector.

9. The laser system according to claim 1 , wherein the judging part is configured to judge any fault or deterioration of the components of the laser system at a predetermined time period.

10. The laser system according to claim 1 , wherein the recording part is configured so that the optical output characteristics recorded by the recording part are overwritten by using optical output characteristics newly acquired when judgment by the judging part is performed.

11. The laser system according to claim 1 , wherein the recording part is configured to record additional optical output characteristics newly acquired when judgment by the judging part is performed.

12. The laser system according to claim 11 , wherein the recording part is configured to record the additional optical output characteristics along with the acquisition time.

13. The laser system according to claim 1 , further comprising a display part displaying results of judgment by the judging part.

Assignees

• Fanuc Corp

Inventors

• Takigawa Hiroshi
• Machida Hisatada

Classifications

• H01S5/0021 Primary

  Degradation or life time measurements · CPC title

• H01S5/0683 Primary

  by monitoring the optical output parameters · CPC title

• H01S5/042 Primary

  Electrical excitation {; Circuits therefor (monolithically integrated laser drive components H01S5/0261)} · CPC title

• H01S5/4012

  Beam combining, e.g. by the use of fibres, gratings, polarisers, prisms · CPC title

• H01S5/02469

  Passive cooling, e.g. where heat is removed by the housing as a whole or by a heat pipe without any active cooling element like a TEC · CPC title