Three-dimensional measuring device and three-dimensional measuring method

• US 6,529,280 B1
• Filed: 10/02/2000
• Issued: 03/04/2003
• Est. Priority Date: 11/17/1995
• Status: Expired due to Term

• Current Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Original Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Inventors: Tanabe, Hideki, Joko, Takuto, Miyazaki, Makoto, Fukumoto, Tadashi, Yagi, Fumiya, Norita, Toshio, Hirose, Satoru, Fujii, Eiro, Sakagawa, Yoshiko, Yahashi, Akira
• Primary Examiner(s): Rosenberger, Richard A.
• Application Number:
  US09/676,767
• Time in Patent Office: 883 Days
• Field of Search: 356/602, 356/603, 356/604, 356/606, 356/607, 356/608
• US Class Current: 356/602
• CPC Class Codes: G01B 11/005 coordinate measuring machines
• CPC Class Codes: G01B 11/2518 Projection by scanning of the object

Abstract

This invention is related to a three-dimensional measuring device for measuring three-dimensional positions of an objects. The three-dimensional measuring device comprises an optical projection system and an optical reception system. In a preliminary measurement prior to an actual measurement, the optical projection system projects slit light beam on the object with varying projection angle with in a narrow range, and the optical reception system receives the slit light beam reflected by the object and generates image signals corresponding to an amount of the received light synchronously with variation of the projection angle. Measurement conditions including intensity of the light beam and the projection angle for the actual measurement are set in accordance with the image signals of the actual measurement. Under the measurement conditions, the actual measurement is executed by projection the light beam on the object with varying the projection angle within a wide range.

Claims

1. A three-dimensional measuring device comprising:

an optical projection system which illuminates an object with light beam;

an image sensor which outputs image signals corresponding to the amount of light impinging the image sensing surface;

an optical reception system which forms an optical image of the object on the image sensing surface of said image sensor, the optical reception system employing a zooming function; and

a calculator for calculating a three-dimensional position of the object based on a front principal point position of said optical reception system and the image signals of the object obtained by said image sensor, the front principal piont position being applied for reducing an accident error arising from the zooming function of said optical reception system.

2. The three-dimensional measuring device as claimed in claim 1 wherein said optical projection system includes an adjusting means for adjusting size of said light beam in accordance with the detection result of the detection means.

3. The three-dimensional measuring device as claimed in claim 2 wherein said adjusting means includes a variator lens for varying the diameter of the laser beam.

4. The three-dimensional measuring device as claimed in claim 1 wherein said optical reception system includes a zooming mechanism for varying the size of the optical image of the object on the image sensing surface.

5. The three-dimensional measuring device as claimed in claim 4 wherein said optical reception system includes an adjusting means for adjusting size of said light beam in accordance with the detection result of the detection means, and said zoom mechanism determines a magnification ration in response to said adjusted size of the light beam.

6. The three-dimensional measuring device as claimed in claim 1, further comprising:

a detector for detecting for front principal point position of said optical reception means.

7. A three-dimensional measuring method comprising steps of:

illuminating an object with light beam;

forming an optical image of the object on an image sensing surface of an image sensor by an optical reception system;

outputting image signals corresponding to the amount of light impinging the image sensing surface;

detecting the principal point position of said optical reception system; and

calculating a three-dimensional position of the object based on the detected principal point position and the image signals.

8. The three-dimensional measuring method as claimed in claim 7 further comprising a step of a adjusting size of said light beam in accordance with the detected principal point position.

9. The three-dimensional measuring device as claimed in claim 8 wherein said adjustment of the light beam size is executed by a variator lens for varying the diameter of the laser beam.

10. A three-dimensional measuring device which projects light on an object and senses the light reflected by said object under variable measurement conditions of the object to obtain three-dimensional positions of the object, said three-dimensional measuring device comprising;

a judging means for judging whether said measurement conditions of the object are acceptable or not; and

a warning means for warning if said judging means judges that said measurement conditions of the object are not acceptable.

11. The three-dimensional measuring device as claimed in claim 10 further comprising a detection means for detecting a distance to the object as the measurement condition, wherein said judging means judges whether the detected distance is acceptable or not.

12. The three-dimensional measuring device as claimed in claim 11 wherein said a detection means detects the distance by executing preliminary measurement prior to an actual measurement.

13. The three-dimensional measuring device as claimed in claim 10 wherein said measuring conditions include an amount of the light reflected by the object, and said judging means judges whether said light amount is acceptable or not.