Camera and method for the three-dimensional measurement of a dental object
AssigneeDENTSPLY SIRONA Inc.
InventorsFrank Thiel, Joachim Pfeiffer
Life of this patent
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Abstract
The invention relates to a method and a camera for the three-dimensional measurement of a dental object, comprising at least one light source that emits an illumination beam, at least one projection mask that produces a projection pattern, focusing optics that display the projection pattern in a plane of sharp focus at a defined focal distance relative to the dental camera. The projection pattern projected onto the object is reflected by the object as an observation beam and is acquired by means of a sensor. During the measurement of the object, the focusing optics are controlled in such a way that the focal distance of the plane of sharp focus relative to the camera is adjusted incrementally between a number of defined scan positions.
Claims13
A camera for the three-dimensional measurement of a dental object, comprising at least one light source that emits an illumination beam, at least one projection mask that produces a projection pattern, focusing optics that display the projection pattern in a plane of sharp focus at a defined focal distance relative to the camera, wherein the projection pattern projected onto the object is reflected by the object as an observation beam and is acquired by means of a sensor,
- wherein during the measurement of the object, the focusing optics are controlled in such a way that the focal distance of the plane of sharp focus relative to the camera is adjusted incrementally between a number of defined scan positions,
- wherein an observation mask is disposed in the beam path of the observation beam in front of the sensor,
- wherein the observation mask is fixedly aligned relative to the projection mask,
- wherein the projection mask includes a plurality of projection pattern elements having a variety of color filters,
- wherein the observation mask includes a plurality of observation mask elements having a variety of color filters,
- wherein an arrangement of the color filters on the projection mask matches another arrangement of the color filters on the observation mask
- wherein dimensions of an image of a specific projection mask element of the projection pattern in the plane of the observation mask correspond to dimensions of a corresponding observation mask element,
- wherein a color filter in the projection mask element and a color filter in the corresponding observation mask element at least partially allow a coinciding spectral range to pass through such that parts of the observation beam of the projection pattern that are disposed within the corresponding observation mask element reach the sensor and/or parts of the observation beam that escape boundaries of the corresponding observation mask element are blocked from reaching the sensor.
A method for the three-dimensional measurement of a dental object using a camera, comprising
- emitting an illumination beam from at least one light source,
- producing a projection pattern from at least one projection mask,
- displaying the projection pattern in a plane of sharp focus at a defined focal distance relative to the camera using focusing optics,
- reflecting as an observation beam, the projection pattern projected onto the dental object,
- acquiring said reflected projection pattern using a sensor,
- controlling the focusing optics in such a way that the focal distance of the plane of sharp focus relative to the camera is adjusted incrementally between a number of defined scan positions,
- disposing an observation mask in the beam path of the observation beam in front of the sensor,
- aligning the observation mask relative to the projection mask,
- wherein the projection mask includes a plurality of projection pattern elements containing a variety of color filters, wherein the observation mask likewise includes a plurality of observation mask elements containing a variety of color filters, wherein the color filters on the projection mask are arranged to match the color filters on the observation mask,
- wherein dimensions of an image of a specific projection mask element of the projection pattern in a plane of the observation mask correspond to dimensions of a corresponding observation mask element,
- wherein a color filter in the projection mask element and a color filter in the corresponding observation mask element at least partially allow a coinciding spectral range to pass through such that parts of the observation beam of the projection pattern that are disposed within the corresponding observation mask element reach the sensor and/or parts of the observation beam that escape boundaries of the corresponding observation mask element are blocked from reaching the sensor.
Dependencies are inferred from the claim text.