Method and apparatus for optical measurement of objects

US5339154A · kind A · utility

Assignee

• KALTENBACH & VOIGT GMBH · DE

Inventors

• Joachim Gassler · Geisingen, DE
• Robert Massen · Schallstadt, DE

Key dates

• Filing date: Oct 15, 1992
• Grant date: Aug 16, 1994
• Expiry date: Oct 15, 2012

Classification

• Technology area (CPC G): Physics
• CPC primary: G16H30/00
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

The invention relates to a method for optical measurement of objects, in particular teeth, with a projector, with beam path diverging from a projector central point, imaging on the object a pattern of different ranges of brightness, which pattern is imaged on the sensor surface of a camera, arranged in a certain disposition in space at a parallax angle to the projector, with a beam path converging in the direction of a camera central point, and is split up into image points, the light intensities of which are measured and stored, and from the light intensities of the image points the phase position of the latter is determined and stored. For the purpose of error-free measurement it is proposed that the position in space of the projector central point, of the camera central point and also of sensor elements of the sensor surface be calculated and stored, the pattern in the plane of projection be split up into image points, the position in space of the latter be calculated and stored, image points of equal phase position be correlated with each other and the position in space of straight lines through image points of equal phase position and the projector and camera central point and…