Method and measurement system for optically measuring an object

• US 10,390,693 B2
• Filed: 04/11/2016
• Issued: 08/27/2019
• Est. Priority Date: 04/09/2015
• Status: Active Grant

• Current Assignee: Dentsply Sirona INC. (Astrazeneca PLC)
• Original Assignee: Dentsply Sirona INC. (Astrazeneca PLC)
• Inventors: Adamson, Anders, Thiel, Frank, Willers, Ulf
• Primary Examiner(s): Suh, Joseph
• Application Number:
  US15/564,436
• Publication Number:
  US 20180078128A1
• Time in Patent Office: 1,233 Days
• CPC Class Codes: A61B 1/24 for the mouth, i.e. stomatoscopes, e.g. with tongue depressors tongue depressors per se A61B13/00; Instruments for opening or keeping open the mouth combined with saliva removers A61C17/00; mouth openers for animals A61D15/00
• CPC Class Codes: A61B 5/0088 for oral or dental tissue
• CPC Class Codes: A61C 9/006 projecting one or more stripes or patterns on the teeth
• CPC Class Codes: A61C 9/0066 Depth determination through adaptive focusing
• CPC Class Codes: G01B 11/022 by means of tv-camera scanning
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures
• CPC Class Codes: G01B 2210/52 Combining or merging partially overlapping images to an overall image
• CPC Class Codes: G01B 9/0203 With imaging systems

Abstract

The invention relates to a measurement system for optically measuring an object, comprising a dental camera and an optical attachment. In this case the optical attachment comprises at least one lens, which is shaped and arranged in such a way that the optical attachment has a negative focal length so that a measurement field or a measurement volume of the dental camera is enlarged by the optical attachment.

Claims

1. A measurement system for optically measuring an object, comprising a dental camera and an optical attachment, wherein the optical attachment includes at least one lens, which is shaped and arranged in such a way that the optical attachment has a negative focal length, so that a measurement field or a measurement volume of the dental camera is enlarged by the optical attachment and wherein the teeth of a patient are measured by means of the dental camera, and a first image of the teeth is generated, wherein at least one portion of the face of the patient is measured by means of the dental camera with the optical attachment with the enlarged measurement field or measurement volume;

and a second image of the face is generated, wherein subsequently the first image of the teeth and the second image of the face are registered to form a composite image.

2. The measurement system as in claim 1, wherein the dental camera is based on a two-dimensional measurement method or on a three-dimensional measurement method.

3. The measurement system as in claim 2, wherein the dental camera is based on a two-dimensional video imaging method, a three-dimensional triangulation measurement method, a three-dimensional confocal measurement method or a white light interferometric measurement method.

4. The measurement system as in claim 1, wherein the optical attachment is detachably connected to the dental camera by means of a connecting means.

5. The measurement system as in claim 1, wherein the measurement field or the measurement volume of the dental camera is enlarged by a magnification factor, which is no less than 5, by means of the optical attachment.

6. The measurement system as in claim 1, wherein the optical attachment additionally includes a beam deflector, which deflects an illuminating beam and an observation beam of the dental camera to the object.

7. The measurement system as in claim 1, wherein the optical attachment comprises a plurality of lenses, which are shaped in such a way and are arranged with respect to each other in such a way that the optical attachment has a negative focal length.

8. The measurement system as in claim 1, wherein the measurement volume of the three-dimensional dental camera in the form of a cube having an edge length between 10 mm and 20 mm is enlarged to an enlarged measurement volume having an edge length of no less than 30 mm by means of the optical attachment.

9. A method for measuring an object by means of a dental camera with a detachable optical attachment, wherein the optical attachment has a negative focal length, so that a measurement field or a measurement volume of the dental camera is enlarged by the optical attachment and wherein the teeth of a patient are measured by means of the dental camera without the optical attachment, and a first image of the teeth is generated, wherein at least one portion of the face of the patient is measured by means of the dental camera with the optical attachment with the enlarged measurement field or measurement volume;

and a second image of the face is generated, wherein subsequently the first image of the teeth and the second image of the face are registered to form a composite image.

10. The method as in claim 9, wherein the dental camera is based on a two-dimensional measurement method or on a three-dimensional measurement method.

11. The method as in claim 10, wherein the dental camera is based on a two-dimensional video imaging method, a three-dimensional triangulation measurement method, a three-dimensional confocal measurement method or a white light interferometric measurement method.

12. The method as in claim 9, wherein by means of the optical attachment the measurement field or the measurement volume of the dental camera is enlarged by a magnification factor that is no less than 5.