WO1998011404A1 - Verfahren zur erhöhung der signifikanz der dreidimensionalen vermessung von objekten - Google Patents
Verfahren zur erhöhung der signifikanz der dreidimensionalen vermessung von objekten Download PDFInfo
- Publication number
- WO1998011404A1 WO1998011404A1 PCT/DE1997/001798 DE9701798W WO9811404A1 WO 1998011404 A1 WO1998011404 A1 WO 1998011404A1 DE 9701798 W DE9701798 W DE 9701798W WO 9811404 A1 WO9811404 A1 WO 9811404A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- pattern
- coded
- projected
- areas
- line
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/25—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
- G01B11/2536—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object using several gratings with variable grating pitch, projected on the object with the same angle of incidence
Definitions
- the invention relates to a method for increasing the significance of the three-dimensional measurement of objects by means of optical recordings, projected patterns and triangulation calculation, in which a coded pattern is projected onto the object in order to avoid manifolds when evaluating the image data
- the prior art includes electronic image converters, for example, CCD arrays stored in output signals immediately after digitization. or can be evaluated
- Tangulation method in which point lines or any other pattern are projected onto the surface under a known angle and the projected pattern is recorded with an optic and an image converter from a different angle of view than the projection angle.
- the known geometry between projection and recording permits the three-dimensional calculation of Support points on the surface
- an object is projected onto an object with spatial dimensions, for example a uniform line pattern results in a distorted line pattern when the viewing direction is different from the projection direction, depending on the surface shape of the object. If the object is depicted from this viewing direction by means of suitable optics on a CCD array, digitized If the image signals are made available to a data processing unit, it is possible to identify the lines at various points in the image and, with knowledge of the optical beam path and taking into account the geometric design of the projected line pattern, to calculate 3D coordinates using triangulation
- the object is achieved according to the invention in that the pattern areas projected for the purpose of three-dimensional measurement of objects with spatial extensions according to the triangulation method are coded in such a way that the assignment to the corresponding area of the projected pattern can be recognized on the basis of a partial image section Beam path, the geometric design of the projected pattern and knowledge of the position of the corresponding pattern section in the image recording can be determined by means of a simple triangulation calculation, absolute 3D coordinates
- the formation of the coded pattern compared to a simple stripe pattern may reduce the number of 3D information that can be calculated
- the information associated with the individual images is compressed and the 3D information is successively completed, be it to supplement the information missing due to undercuts in individual images, or to represent larger objects than is possible due to the limitations of the field of view of the recording unit in a single image is
- coded are areas of the projected pattern that can be significantly differentiated with regard to their geometric design and / or extension and / or their other, for example, colored design.
- the lines according to the invention can advantageously, for. B. can be encoded by varying the stroke width within the respective line.
- binary other discrete and analog encodings can be used.
- - secondly - the contrast data of the digitized image information in the memory of a data processing unit are flat, that is, they are organized in rows and columns and represent - thirdly - the column data, for example the image information in the direction of the plane, which is spanned between the recording and projection device, can be automated evaluation the data in a suitable algorithm for the purpose of calculating the absolute 3D coordinates in such a way that the contrast data along an image column are checked for agreement with the pattern sequence dark / light / dark.
- the corresponding statistical and numerical methods such as cross correlation, Wiener- Filters etc. also known for the subpixel evaluation.
- the course and the formation of the line in the adjacent columns can be examined via edge tracking.
- the line itself can thus be examined with regard to its formation and thus its coding.
- the result is - firstly - the column position at which the line with its pattern focus was recorded and - secondly - the corresponding one Line segment decoded, so the line segment can be uniquely assigned to the corresponding pattern location in the undistorted and projection-based pattern. From this information, the 3D coordinates for a corresponding point on the surface of the object under consideration can be determined using triangulation calculation
- the exact three-dimensional digital description possible with the above method makes it possible to dispense with spatial impressions (such as plaster casts) for the documentation of findings in three-dimensional content or for the computer-assisted preparation of therapeutic agents (such as toothing, dentures, Implants).
- spatial impressions such as plaster casts
- therapeutic agents such as toothing, dentures, Implants
- the lines can be different from the variation of short and long line segments with single or double line widths along a line analogous to the Morse code If lines now fall into a shadowed area, absolute 3D coordinates can still be calculated for each visible line segment that contains the complete coding, without information about other lines or
- the segments with different black components can be arranged in a linear or concentric manner
- a color coding of the pattern can be carried out particularly advantageously according to the invention. If lines are used as a pattern, according to the invention, for example, each line can advantageously be designed in a different color each line must be clearly identified, provided that the color content of the recorded
- color is understood to mean a selection of spectral lines and spectral ranges of visible, infrared and / or ultraviolet light. In the sense of this definition, it is irrelevant whether the color by
- black is used synonymously for essentially unilluminated and / or for essentially no retroreflective or transmitted-radiation component due to absorption
- the line width along the respective line is alternately in single or double width in a regularly repeated sequence
- Line width executed in such a way that in a defined line section the length ratio of the pieces with single and double line width is different from line to line.
- the embodiment shown in FIG. 1 is characterized in that, due to the special design of the pattern, a high density of the calculable support points can be achieved
- FIG. 2 shows an arrangement of concentric pattern elements, the individual elements being coded in such a way that - firstly - the inner circle in 90 ° segments is blackened differently, - secondly - the outer concentric ring is blackened differently in 90 ° segments and - thirdly - the
- the outer concentric ring pattern is configured differently from the higher-level element arrangement.
- the embodiment shown in FIG. 2 is characterized in addition to the coding of the sample parts in that a) a high level of significance of the coding can be achieved by the three mentioned possibilities of different training of the individual sample element, and in this respect
- Pattern recognition algorithms are suitable.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Length Measuring Devices By Optical Means (AREA)
- Image Processing (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP51311298A JP2001505302A (ja) | 1996-09-12 | 1997-08-19 | 物体の三次元計測の意義を向上させるための方法 |
EP97938789A EP0935737A1 (de) | 1996-09-12 | 1997-08-19 | Verfahren zur erhöhung der signifikanz der dreidimensionalen vermessung von objekten |
AU41115/97A AU4111597A (en) | 1996-09-12 | 1997-08-19 | Method for increasing the significance of tridimensional measuring of objects |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19638727.2 | 1996-09-12 | ||
DE1996138727 DE19638727A1 (de) | 1996-09-12 | 1996-09-12 | Verfahren zur Erhöhung der Signifikanz der dreidimensionalen Vermessung von Objekten |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998011404A1 true WO1998011404A1 (de) | 1998-03-19 |
Family
ID=7806439
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/DE1997/001798 WO1998011404A1 (de) | 1996-09-12 | 1997-08-19 | Verfahren zur erhöhung der signifikanz der dreidimensionalen vermessung von objekten |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0935737A1 (de) |
JP (1) | JP2001505302A (de) |
CN (1) | CN1231724A (de) |
AU (1) | AU4111597A (de) |
DE (1) | DE19638727A1 (de) |
WO (1) | WO1998011404A1 (de) |
Cited By (6)
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US6413084B1 (en) | 2000-04-28 | 2002-07-02 | Ora Metrix, Inc. | Method and system of scanning |
US6532299B1 (en) | 2000-04-28 | 2003-03-11 | Orametrix, Inc. | System and method for mapping a surface |
US6648640B2 (en) | 1999-11-30 | 2003-11-18 | Ora Metrix, Inc. | Interactive orthodontic care system based on intra-oral scanning of teeth |
JP2005201896A (ja) * | 2000-04-28 | 2005-07-28 | Orametrix Inc | 表面を走査し三次元物体を作製するための方法及びシステム |
US7068836B1 (en) | 2000-04-28 | 2006-06-27 | Orametrix, Inc. | System and method for mapping a surface |
CN100449258C (zh) * | 2006-04-27 | 2009-01-07 | 浙江工业大学 | 基于二维彩色光编码的实时三维视觉系统 |
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DE19821611A1 (de) * | 1998-05-14 | 1999-11-18 | Syrinx Med Tech Gmbh | Verfahren zur Erfassung der räumlichen Struktur einer dreidimensionalen Oberfläche |
US6771809B1 (en) | 2000-04-28 | 2004-08-03 | Orametrix, Inc. | Method and system for registering data |
US6744932B1 (en) | 2000-04-28 | 2004-06-01 | Orametrix, Inc. | System and method for mapping a surface |
US6738508B1 (en) | 2000-04-28 | 2004-05-18 | Orametrix, Inc. | Method and system for registering data |
US6512994B1 (en) | 1999-11-30 | 2003-01-28 | Orametrix, Inc. | Method and apparatus for producing a three-dimensional digital model of an orthodontic patient |
US7068825B2 (en) | 1999-03-08 | 2006-06-27 | Orametrix, Inc. | Scanning system and calibration method for capturing precise three-dimensional information of objects |
US6744914B1 (en) | 2000-04-28 | 2004-06-01 | Orametrix, Inc. | Method and system for generating a three-dimensional object |
US6688885B1 (en) | 1999-11-30 | 2004-02-10 | Orametrix, Inc | Method and apparatus for treating an orthodontic patient |
US6554613B1 (en) | 2000-04-19 | 2003-04-29 | Ora Metrix, Inc. | Method and apparatus for generating an orthodontic template that assists in placement of orthodontic apparatus |
US6736638B1 (en) | 2000-04-19 | 2004-05-18 | Orametrix, Inc. | Method and apparatus for orthodontic appliance optimization |
US6318995B1 (en) | 2000-04-19 | 2001-11-20 | Drametrix, Inc. | Method and apparatus for bonding a bracket to a tooth |
DE19963333A1 (de) * | 1999-12-27 | 2001-07-12 | Siemens Ag | Verfahren zur Ermittlung von dreidimensionalen Oberflächenkoordinaten |
US7027642B2 (en) | 2000-04-28 | 2006-04-11 | Orametrix, Inc. | Methods for registration of three-dimensional frames to create three-dimensional virtual models of objects |
US7471821B2 (en) | 2000-04-28 | 2008-12-30 | Orametrix, Inc. | Method and apparatus for registering a known digital object to scanned 3-D model |
WO2004001332A1 (en) * | 2002-06-19 | 2003-12-31 | Canesta, Inc. | System and method for determining 3-d coordinates of a surface using a coded array |
DE10232690A1 (de) | 2002-07-18 | 2004-02-12 | Siemens Ag | Verfahren und Vorrichtung zur dreidimensionalen Erfassung von Objekten sowie Verwendung der Vorrichtung und des Verfahrens |
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WO2007105205A2 (en) | 2006-03-14 | 2007-09-20 | Prime Sense Ltd. | Three-dimensional sensing using speckle patterns |
US8400494B2 (en) | 2005-10-11 | 2013-03-19 | Primesense Ltd. | Method and system for object reconstruction |
US9330324B2 (en) | 2005-10-11 | 2016-05-03 | Apple Inc. | Error compensation in three-dimensional mapping |
WO2007096893A2 (en) | 2006-02-27 | 2007-08-30 | Prime Sense Ltd. | Range mapping using speckle decorrelation |
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KR101408959B1 (ko) | 2006-03-14 | 2014-07-02 | 프라임센스 엘티디. | 삼차원 감지를 위한 깊이 가변 광 필드 |
US8090194B2 (en) | 2006-11-21 | 2012-01-03 | Mantis Vision Ltd. | 3D geometric modeling and motion capture using both single and dual imaging |
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US8150142B2 (en) | 2007-04-02 | 2012-04-03 | Prime Sense Ltd. | Depth mapping using projected patterns |
US8493496B2 (en) | 2007-04-02 | 2013-07-23 | Primesense Ltd. | Depth mapping using projected patterns |
JP2008275392A (ja) * | 2007-04-26 | 2008-11-13 | National Institute Of Advanced Industrial & Technology | 3次元形状計測方法および装置 |
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US8462207B2 (en) | 2009-02-12 | 2013-06-11 | Primesense Ltd. | Depth ranging with Moiré patterns |
US8786682B2 (en) | 2009-03-05 | 2014-07-22 | Primesense Ltd. | Reference image techniques for three-dimensional sensing |
US8717417B2 (en) | 2009-04-16 | 2014-05-06 | Primesense Ltd. | Three-dimensional mapping and imaging |
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US8830227B2 (en) | 2009-12-06 | 2014-09-09 | Primesense Ltd. | Depth-based gain control |
US8982182B2 (en) | 2010-03-01 | 2015-03-17 | Apple Inc. | Non-uniform spatial resource allocation for depth mapping |
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US9448064B2 (en) | 2012-05-24 | 2016-09-20 | Qualcomm Incorporated | Reception of affine-invariant spatial mask for active depth sensing |
CN103983213B (zh) * | 2014-05-30 | 2016-12-07 | 深圳先进技术研究院 | 一种结构光编码方法及相关装置 |
EP3315902B1 (de) * | 2016-10-27 | 2023-09-06 | Pepperl+Fuchs SE | Messvorrichtung und verfahren zur triangulationsmessung |
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DE102016222244A1 (de) * | 2016-11-14 | 2018-05-17 | Siemens Aktiengesellschaft | Verfahren und Vorrichtung zur Tiefenbestimmung eines Objektes |
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-
1996
- 1996-09-12 DE DE1996138727 patent/DE19638727A1/de not_active Withdrawn
-
1997
- 1997-08-19 WO PCT/DE1997/001798 patent/WO1998011404A1/de not_active Application Discontinuation
- 1997-08-19 JP JP51311298A patent/JP2001505302A/ja active Pending
- 1997-08-19 EP EP97938789A patent/EP0935737A1/de not_active Withdrawn
- 1997-08-19 CN CN 97197836 patent/CN1231724A/zh active Pending
- 1997-08-19 AU AU41115/97A patent/AU4111597A/en not_active Abandoned
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US4185918A (en) * | 1975-08-27 | 1980-01-29 | Solid Photography Inc. | Arrangement for sensing the characteristics of a surface and determining the position of points thereon |
CA2163934A1 (en) * | 1994-11-29 | 1996-05-30 | Alexander Thomas Hermany | Electromagnetic profile scanner |
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Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6648640B2 (en) | 1999-11-30 | 2003-11-18 | Ora Metrix, Inc. | Interactive orthodontic care system based on intra-oral scanning of teeth |
US7029275B2 (en) | 1999-11-30 | 2006-04-18 | Orametrix, Inc. | Interactive orthodontic care system based on intra-oral scanning of teeth |
US6413084B1 (en) | 2000-04-28 | 2002-07-02 | Ora Metrix, Inc. | Method and system of scanning |
US6532299B1 (en) | 2000-04-28 | 2003-03-11 | Orametrix, Inc. | System and method for mapping a surface |
JP2005201896A (ja) * | 2000-04-28 | 2005-07-28 | Orametrix Inc | 表面を走査し三次元物体を作製するための方法及びシステム |
JP2005214965A (ja) * | 2000-04-28 | 2005-08-11 | Orametrix Inc | 表面を走査し三次元物体を作製するための方法及びシステム |
US7068836B1 (en) | 2000-04-28 | 2006-06-27 | Orametrix, Inc. | System and method for mapping a surface |
CN100449258C (zh) * | 2006-04-27 | 2009-01-07 | 浙江工业大学 | 基于二维彩色光编码的实时三维视觉系统 |
Also Published As
Publication number | Publication date |
---|---|
JP2001505302A (ja) | 2001-04-17 |
EP0935737A1 (de) | 1999-08-18 |
DE19638727A1 (de) | 1998-03-19 |
AU4111597A (en) | 1998-04-02 |
CN1231724A (zh) | 1999-10-13 |
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