Laser fabrication with beam detection

Patent metadata

Field	Value
Publication number	US-11262236-B2
Application number	US-202016814820-A
Country	US
Kind code	B2
Filing date	Mar 10, 2020
Priority date	Apr 12, 2019
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

A computer numerically controlled machine may include a source of electromagnetic energy. A beam of electromagnetic energy from the source may be delivered to a destination such as, for example, a material positioned in a working area of the computer numerically controlled machine. The beam of electromagnetic energy may be susceptible to interferences while traveling from the source to the destination. The computer numerically controlled machine may include a beam detector configured detect an interference of the beam by measuring a power of the beam of electromagnetic energy at a location between the source and the destination. An interference of the beam may be detected if the power of the beam is less than a threshold value. A controller at the computer numerically controlled machine may perform one or more actions in response to the beam detector detecting the interference of the beam of electromagnetic energy.

First claim

What is claimed is:

1. A method, comprising:
delivering, to a destination in a computer numerically controlled machine, a beam of electromagnetic energy;
measuring a power of the beam of electromagnetic energy at a location between a source of the electromagnetic energy and the destination, the beam of electromagnetic energy traveling from the source to the destination being susceptible to one or more interferences, and the one or more interferences being capable of altering the power of the beam of electromagnetic energy by at least diverting, away from an intended path for the beam of electromagnetic energy, at least a portion of the beam of electromagnetic energy;
detecting, based at least on the power of the beam of electromagnetic energy being less than a threshold value, an interference of the beam of electromagnetic energy; and
in response to detecting the interference of the beam of electromagnetic energy, performing one or more actions.

2. The method of claim 1 , wherein the power of the beam of electromagnetic energy is measured by a beam detector.

3. The method of claim 2 , wherein the beam detector is disposed at a head of the computer numerically controlled machine, and wherein the head of the computer numerically controlled machine is configured to steer, to the destination, the beam of electromagnetic energy from the source of the electromagnetic energy.

4. The method of claim 3 , wherein the beam detector is configured to measure the power of the beam of electromagnetic energy by at least measuring a power of a backscatter from the beam of electromagnetic energy interacting with one or more components at the head of the computer numerically controlled machine.

5. The method of claim 2 , wherein the beam detector is configured to measure the power of the beam of electromagnetic energy by at least measuring a power of one or more divergent rays scattered from the beam of electromagnetic energy.

6. The method of claim 2 , wherein the beam detector is configured to measure the power of the beam of electromagnetic energy by at least measuring a power of a backscatter from the beam of electromagnetic energy delivered at the destination.

7. The method of claim 2 , wherein the beam detector is configured to measure the power of the beam of electromagnetic energy by at least measuring a power of a portion of the beam of electromagnetic energy.

8. The method of claim 7 , wherein the portion of the beam of electromagnetic energy is diverted to the beam detector by a bypass that enables the portion of the beam of electromagnetic energy to pass through an optical element configured to steer the beam of electromagnetic energy.

9. The method of claim 7 , wherein the portion of the beam of electromagnetic energy is diverted to the beam detector by an optical element and/or an optical obstacle inserted along the intended path of the beam of electromagnetic energy.

10. The method of claim 1 , further comprising:
determining an expected power of the beam of electromagnetic energy at the location between the source of the electromagnetic energy and the destination; and
detecting the interference of the beam of electromagnetic energy further based on a difference between the power of the beam of electromagnetic energy and the expected power of the beam of electromagnetic energy exceeding another threshold value.

11. The method of claim 10 , wherein the threshold value and/or the other threshold value are determined based at least on a maximum permissible exposure (MPE) associated with the beam of electromagnetic energy.

12. The method of claim 10 , wherein the expected power of the beam of electromagnetic energy is determined based at least on an initial power of the beam of electromagnetic energy at the source of the electromagnetic energy and/or an attenuation of the power of the beam of electromagnetic energy as the beam of electromagnetic energy propagates from the source to the destination.

13. The method of claim 1 , wherein the measuring of the power of the beam of electromagnetic energy includes:
generating, by a first sensor oriented towards the source of the electromagnetic energy, a first measurement;
generating, by a second sensor oriented away from the source of the electromagnetic energy, a second measurement; and
determining, based at least on a difference between the first measurement and the second measurement, the power of the beam of electromagnetic energy, the difference between the first measurement and the second measurement corresponding to a contribution from an ambient noise, and the power of the beam of electromagnetic energy being determined by at least removing the contribution from the ambient noise.

14. The method of claim 13 , wherein the measuring the power of the beam of electromagnetic energy includes filtering a signal detected by the first sensor and/or the second sensor to remove the contribution from the ambient noise.

15. The method of claim 13 , wherein the first sensor and/or the second sensor are configured to detect electromagnetic energy in a far infrared region of the electromagnetic spectrum.

16. The method of claim 13 , wherein the first sensor and/or the second sensor comprise thermopiles.

17. The method of claim 1 , wherein the one or more actions include at least one of generating an alarm, sending a notification to a user, disabling the source of the electromagnetic energy, and engaging an interlock of the computer numerically controlled machine.

18. The method of claim 1 , wherein the one or more actions include sending, to a cloud-based server, data collected by one or more sensors onboard the computer numerically controlled machine, and wherein the data is collected over a time period during which the interference of the electromagnetic energy occurred at the computer numerically controlled machine.

19. The method of claim 1 , wherein the one or more interferences include an absence and/or a malfunction of an optical element configured to direct the beam of electromagnetic energy to the destination.

20. The method of claim 1 , wherein the one or more interferences include an obstacle introduced to an unprotected portion of the intended path between the source of the electromagnetic energy and the destination.

21. An apparatus, comprising:
a head configured to steer, to a destination, a beam of electromagnetic energy from a source of electromagnetic energy;
a beam detector disposed at the head, the beam detector configured to measure a power of the beam of electromagnetic energy at a location between the source of the electromagnetic energy and the destination, the beam of electromagnetic energy traveling from the source to the destination being susceptible to one or more interferences, and the one or more interferences being capable of altering the power of the beam of electromagnetic energy by at least diverting, away from an intended path for the beam of electromagnetic energy, at least a portion of the beam of electromagnetic energy; and
a controller configured to detect, based at least on the power of the beam of electromagnetic energy being less than a threshold value, an interference of the beam of electromagnetic energy, and respond to detecting the interference of the beam of electromagnetic energy by performing one or more actions.

22. The apparatus of claim 21 , wherein the beam detector is configured to measure the power of the beam of electromagnetic energy by at least measuring a power of a backscatter from the bea

Assignees

• Glowforge Inc

Inventors

• Shapiro Daniel
• Gosselin Mark
• Kloiber Eva
• Kofron Jared
• Sarnoff Matthew

Classifications

• B23K37/0235

  the guide member forming part of a portal · CPC title

• B23K26/0876

  in at least two axial directions · CPC title

• G01J1/4228 Primary

  arrangements with two or more detectors, e.g. for sensitivity compensation · CPC title

• G01J1/10

  by comparison with reference light or electric value {provisionally void} · CPC title

• G01J1/4257 Primary

  applied to monitoring the characteristics of a beam, e.g. laser beam, headlamp beam (monitoring arrangements for lasers in general H01S3/0014) · CPC title