Three-dimensional shape-measuring system

• US 20020171847A1
• Filed: 04/24/2002
• Published: 11/21/2002
• Est. Priority Date: 04/27/2001
• Status: Active Grant

• Current Assignee: Masahiro Ariizumi, Norio Matsunaga, Shigeru Osaki, Tadashi Fukumoto, Yoshihisa Abe
• Original Assignee: Masahiro Ariizumi, Norio Matsunaga, Shigeru Osaki, Tadashi Fukumoto, Yoshihisa Abe
• Inventors: Osaki, Shigeru, Matsunaga, Norio, Abe, Yoshihisa, Fukumoto, Tadashi, Ariizumi, Masahiro
• Granted Patent: US 6,798,527 B2
• Time in Patent Office: Days
• US Class Current: 356/606
• CPC Class Codes: G01B 11/245 using a plurality of fixed, simultaneously operating transducers G01B11/2408 - G01B11/2425, G01B11/255 take precedence
• CPC Class Codes: G01B 11/2518 Projection by scanning of the object

Abstract

An object of the present invention is to provide a method for accurately measuring a three-dimensional shape of a measuring subject independent of the surface shape of the measuring subject, and another object thereof is to shorten the time from the measurements of the measuring subject until three-dimensional shape data is obtained so as to carry out efficient measuring operations. In a three-dimensional measuring system 1 that measures a three-dimensional shape of a measuring subject, two three-dimensional measuring devices 10, 20 are placed. The three-dimensional measuring device 10 measures a measuring subject placed in a measuring space 3 by allowing a laser slit light L1 in a longitudinal direction to scan in a lateral direction. Moreover, the three-dimensional measuring device 20 measures the measuring subject placed in a measuring space 3 by allowing the laser slit light L1 in a lateral direction to scan in a longitudinal direction.

Claims

1. A three-dimensional shape-measuring system, which measures a three-dimensional shape of a measuring subject by using a light section method, comprising:

a first light projector which directs first laser light to said measuring subject so that said first laser light is allowed to scan the surface of said measuring subject in a first direction;

a second light projector which directs second laser light to said measuring subject so that said second laser light is allowed to scan the surface of said measuring subject in a second direction different from said first direction;

a light receiver which receives first reflected light derived from said first laser light reflected from said measuring subject and second reflected light derived from said second laser light reflected from said measuring subject; and

a calculator which calculates a three-dimensional shape of said measuring subject based upon data obtained from said light receiver.

2. The three-dimensional shape-measuring system according to claim 1, wherein,

said first light projector and said second light projector are placed at respectively different positions, and said first laser light and said second laser light are directed to said measuring subject from respectively different positions.

6. The three-dimensional shape-measuring system according to claim 1, wherein,

said first laser light is slit light that is distributed in a direction orthogonal to said first direction, and said second laser light is slit light that is distributed in a direction orthogonal to said second direction.

7. The three-dimensional shape-measuring system according to claim 1, wherein,

said light receiver includes a first receiver for receiving said first reflected light and a second receiver for receiving said second reflected light.

9. The three-dimensional shape-measuring system according to claim 1, further comprising,

a rotation stage which supports said measuring subject within an irradiation range of said first laser light and said second laser light, and pivots centered on a predetermined rotation axis to rotate said measuring subject within said irradiation range.

3. A three-dimensional shape-measuring system, which measures a three-dimensional shape of a measuring subject by using a light section method, comprising:

a first light projector which directs first laser light to said measuring subject so as to allow said first laser light to scan the surface of said measuring subject;

a second light projector which directs second laser light to said measuring subject so as to allow said second laser light to scan the surface of said measuring subject;

a light receiver which receives first reflected light derived from said first laser light reflected from said measuring subject and second reflected light derived from said second laser light reflected from said measuring subject; and

a calculator which calculates a three-dimensional shape of said measuring subject based upon data obtained from said light receiver,

wherein first base length connecting said first light projector and said light receiver has a first base length direction and second base length connecting said second light projector and said light receiver has a second base length direction, said first base length direction and said second base length direction being set in non-parallel with each other.

4. The three-dimensional shape-measuring system according to claim 3, wherein,

said first base length direction and said second base length direction are orthogonal to each other.

5. The three-dimensional shape-measuring system according to claim 3, wherein,

said first light projector allows said first laser light to scan the surface of said measuring subject in a first direction;

and

said second light projector allows said second laser light to scan the surface of said measuring subject in a second direction different from said first direction.

8. The three-dimensional shape-measuring system according to claim 3, wherein,

said light receiver includes a first receiver for receiving said first reflected light and a second receiver for receiving said second reflected light.

10. The three-dimensional shape-measuring system according to claim 3, further comprising,

a rotation stage which supports said measuring subject within an irradiation range of said first laser light and said second laser light, and pivots centered on a predetermined rotation axis to rotate said measuring subject within said irradiation range.

11. A three-dimensional shape-measuring system, which directs laser light to a measuring subject placed in a measuring space from a plurality of directions by using a light projector so that a light receiver detects reflected light derived from said laser light from said light projector reflected by said measuring subject to generate a three-dimensional shape data of said measuring subject, comprising:

a controller which, prior to measurements on said measuring subject, controls said light projector and said light receiver so as to measure a calibration-use subject placed in said measuring space from said plurality of directions;

a data processor which finds a conversion parameter used for converting measured data related to said calibration-use subject, obtained respectively in said plurality of directions, to three-dimensional shape data in a world coordinate system; and

a memory storing said conversion parameter;

wherein

said three-dimensional shape data is generated by data-converting said measured data related to said calibration-use subject, obtained respectively in said plurality of directions, by the use of said conversion parameter.

12. The three-dimensional shape-measuring system according to claim 11, wherein,

said data processor finds a conversion parameter used for calibrating relative position and orientation when measuring operations are carried out respectively in said plurality of directions.

13. The three-dimensional shape-measuring system according to claim 11, further comprising:

a rotation stage which rotates said measuring subject located in said measuring space,

wherein said data processor finds the position of the rotation axis of said rotation stage from measured data related to said calibration-use subject obtained respectively in said plurality of directions to find a conversion parameter used for rotation-shifting measured data around said rotation axis.

14. The three-dimensional shape-measuring system according to claim 11, wherein,

said data processor finds a conversion parameter used for composing measured data related to said calibration-use subject obtained respectively in said plurality of directions.

15. The three-dimensional shape-measuring system according to claim 14, wherein,

said data processor finds a conversion parameter which compares measured data related to said calibration-use subject obtained respectively in said plurality of directions with known data of said calibration-use subject to make said measured data closer to said known data.

16. The three-dimensional shape-measuring system according to claim 11, wherein,

said measured data contains information related to measuring magnifications used when measuring operations are carried out respectively in said plurality of directions, and

said data processor processes said measured data in accordance with said measuring magnifications.