Measurement of melt pool position in additive manufacturing
AssigneeNikon Corporation
InventorsEric Peter Goodwin, Zhi-Wei Lin
Life of this patent
Estimating the term…
Abstract
Detectors are situated along a tilted optical axis to receive optical radiation from a work surface. Variations in the received optical power are used to estimate a work surface positional along a work surface axis. The received optical power can be emitted from the work surface and an estimated temperature of the work surface used to adjust the received optical power. One or two single element detectors or a linear detector can be used. A position of a focused spot produced from the received optical power at the linear detector can be used to assess work surface axial position.
Claims39
A detecting device that detects a melt pool produced by a processing beam that forms the melt pool, the detecting device comprising:
- a first light receiving device that receives a first radiation emitted from the melt pool along a first axis and caused by the processing beam;
- a second light receiving device that receives a second radiation emitted from the melt pool along a second axis inclined with respect to the first axis and caused by the processing beam;
- and
- a controller,
- wherein the first light receiving device includes a first photodetector that photoelectrically converts the first radiation, the second light receiving device includes a second photodetector that photoelectrically converts the second radiation, and the controller calculates a first output from the first photodetector and a second output from the second photodetector to obtain a dimension of the melt pool based on the first output and the second output.
A detecting device that detects a melt pool produced by a processing beam that forms the melt pool, the detecting device comprising:
- a first light receiving device that receives a first radiation emitted from the melt pool along a first axis and caused by the processing beam;
- and
- a second light receiving device that receives a second radiation emitted from the melt pool along a second axis inclined with respect to the first axis and caused by the processing beam, wherein the second light receiving device comprises:
- a tracking optical system situated along a tracking axis, the tracking optical system comprising at least one focus element and at least one photodetector, wherein the at least one focus element is situated to receive optical radiation from the melt pool and direct the received optical radiation toward the at least one photodetector, wherein the tracking axis is tilted with respect to a processing axis of the processing beam and the at least one photodetector includes at least one single pixel photodetector or a linear detector;
- and
- an optical receiver coupled to the at least one photodetector and operable to produce a tracking signal associated with a position of the melt pool along the processing axis or a melt pool axis perpendicular to the melt pool based on the received optical radiation directed to the at least one photodetector.
A detecting method of detecting a melt pool produced by a processing beam that forms the melt pool, the method comprising:
- receiving a first radiation emitted from the melt pool along a first axis and caused by the processing beam, the first radiation received by a first light receiving device that includes a first photodetector that photoelectrically converts the first radiation;
- receiving a second radiation emitted from the melt pool along a second axis inclined with respect to the first axis and caused by the processing beam, the second radiation received by a second light receiving device that includes a second photodetector that photoelectrically converts the second radiation;
- and
- calculating, by a controller, a first output from the first photodetector and a second output from the second photodetector to obtain a dimension of the melt pool based on the first output and the second output.
Dependencies are inferred from the claim text.