Machine vision system and method with on-axis aimer and distance measurement assembly
AssigneeCognex Corporation
InventorsJose Fernandez-Dorado, Pablo Garcia-Campos, Laurens Nunnink
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Abstract
An on-axis aimer and distance measurement apparatus for a vision system can include a light source configured to generate a first light beam along a first axis. The first light beam can project an aimer pattern on an object and a receiver can be configured to receive reflected light from the first light beam to determine a distance between a lens of the vision system and the object. One or more parameters of vision system can be controlled based on the determined distance.
Claims20
An apparatus for automatically focusing a reader having an optical axis in a vision system, the apparatus comprising:
- an optics assembly having at least one lens and an image sensor;
- an on-axis aimer and distance measurement assembly comprising:
- a light source configured to generate a first light beam along a first axis, the first light beam configured to project an aimer pattern on an object;
- a receiver configured to receive reflected light from the object based on the first light beam, the reflected light provided to the receiver along a second axis;
- a reflecting assembly configured to direct the first light beam received from the light source so that the first light beam is projected onto the object coaxially with the reader optical axis and configured to direct the reflected light from the optical axis to the second axis;
- and
- a processor device in communication with the receiver and the optics assembly and configured to determine a distance between the at least one lens and the object based on the reflected light and to focus the at least one lens based on the determined distance.
An on-axis aimer and distance measurement apparatus for a vision system comprising:
- a light source configured to generate a first light beam along a first axis, the first light beam configured to project an aimer pattern on an object;
- a reflecting assembly configured to direct the first light beam received from the light source to be projected onto the object along a second axis and configured to receive reflected light from the first light beam on the object along the second axis, and to direct the reflected light from the second axis to a third axis;
- a receiver configured to receive the reflected light along the third axis to determine a distance between a lens of the vision system and the object;
- and
- a processor device configured to control one or more parameters of the vision system for acquisition of an image of the object based on the determined distance.
A method for acquiring an image of a symbol on an object using a vision system having at least one lens, the method comprising:
- projecting a first light beam to the object coaxially with a reader optical axis of the vision system, to project an aimer pattern on the object;
- receiving reflected light from the object based on the first light beam, coaxially with the reader optical axis;
- directing the reflected light to an axis different from the reader optical axis;
- determining, using one or more processor devices, a distance between the at least one lens of the vision system and the object based on the reflected, directed light from the first light beam;
- determining, using the one or more processor devices, a desired optical power for the at least one lens based on the determined distance;
- adjusting, using the one or more processor devices, a focus of the at least one lens based on the desired optical power;
- and
- acquiring an image of the symbol on the object.
Dependencies are inferred from the claim text.