Laser measurement apparatus

• US 20040233460A1
• Filed: 04/13/2004
• Published: 11/25/2004
• Est. Priority Date: 05/19/2003
• Status: Active Grant

• Current Assignee: Soatec Incorporated
• Original Assignee: Soatec Incorporated
• Inventors: Ono, Makoto, Ohno, Yasuomi, Ura, Haruo
• Granted Patent: US 7,196,795 B2
• Time in Patent Office: Days
• US Class Current: 356/601
• CPC Class Codes: G01S 17/36 with phase comparison between the received signal and the contemporaneously transmitted signal
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/4812 transmitted and received beams following a coaxial path
• CPC Class Codes: G01S 7/4813 Housing arrangements
• CPC Class Codes: G01S 7/4815 using multiple transmitters
• CPC Class Codes: G01S 7/4818 using optical fibres
• CPC Class Codes: G01S 7/497 Means for monitoring or calibrating

Abstract

A laser measurement apparatus for carrying out measurement using a laser beam that is capable of performing various types of measurement with a simple structure is provided. Optical signal processing units 103, 104, 105 output laser beams λ1, λ2, λ3 having different wavelengths via a common optical path A toward an object to be measured, and detect the laser beams being reflected by a corner cube 100 attached to the object to be measured. A control unit 102 controls motors 110, 111 so that the laser beams return to a predetermined position of a optical position sensing device 117 of an optical signal processing unit 103, according to which the direction of a reflecting mirror 112 is controlled so that the laser beams follow the object. The control unit 102 computes the distance to the object, or the shape, position, speed etc. of the object based on signals detected at the optical signal processing units 104, 105.

Claims

1. A laser measurement apparatus comprising:

a plurality of laser beam generating means for outputting laser beams having different characteristics;

a plurality of optical signal processing means disposed so as to correspond to each of the laser beams for detecting the corresponding laser beam and carrying out a predetermined process; and

an optical path means for guiding the laser beams output from the plurality of laser beam generating means via a common optical path to an object and for guiding the laser beams returning from the object via the common optical path to the optical signal processing means.

2. The laser measurement apparatus according to claim 1, wherein

the optical path means includes an optical guiding means;

and

the laser measurement apparatus further comprises a control means for controlling the optical guiding means so as to guide the laser beams output from the plurality of laser beam generating means toward the object and to guide the laser beams returning from the object toward the plurality of optical signal processing means.

3. The laser measurement apparatus according to claim 2, wherein

the optical guiding means is a reflecting mirror;

and

the control means controls the reflecting mirror to reflect the laser beams output from the plurality of laser beam generating means toward the object and to reflect the laser beams returning from the object back toward the plurality of optical signal processing means.

4. The laser measurement apparatus according to claim 3, wherein

one of the plurality of laser beams having different characteristics is a laser beam used for tracking, and the optical signal processing means corresponding to this laser beam comprises an optical position sensing device;

and

the control means controls the direction of the reflecting mirror so that the laser beams output from the plurality of laser beam generating means are reflected toward the object based on signals output from the optical position sensing device.

5. The laser measurement apparatus according to claim 1, wherein

the plurality of laser beams having different characteristics include plural laser beams for measuring distances according to different measurement scales, and the optical signal processing means corresponding to each of the laser beams have photodetectors that detect the presence or absence of a beam that of a predetermined level and above, and outputs a signal corresponding to the presence or absence of such beam;

and

the control means computes a distance between the object and a reference position based on the output signals from each of the photodetectors.

6. The laser measurement apparatus according to claim 2, wherein

the plurality of laser beams having different characteristics include plural laser beams for measuring distances according to different measurement scales, and the optical signal processing means corresponding to each of the laser beams have photodetectors that detect the presence or absence of a beam that of a predetermined level and above, and outputs a signal corresponding to the presence or absence of such beam;

and

the control means computes a distance between the object and a reference position based on the output signals from each of the photodetectors.

7. The laser measurement apparatus according to claim 3, wherein

the plurality of laser beams having different characteristics include plural laser beams for measuring distances according to different measurement scales, and the optical signal processing means corresponding to each of the laser beams have photodetectors that detect the presence or absence of a beam that of a predetermined level and above, and outputs a signal corresponding to the presence or absence of such beam;

and

the control means computes a distance between the object and a reference position based on the output signals from each of the photodetectors.

8. The laser measurement apparatus according to claim 4, wherein

the plurality of laser beams having different characteristics include plural laser beams for measuring distances according to different measurement scales, and the optical signal processing means corresponding to each of the laser beams have photodetectors that detect the presence or absence of a beam that of a predetermined level and above, and outputs a signal corresponding to the presence or absence of such beam;

and

the control means computes a distance between the object and a reference position based on the output signals from each of the photodetectors.

9. The laser measurement apparatus according to claim 1, wherein the optical path means includes an optical fiber cable.

10. The laser measurement apparatus according to claim 2, wherein the optical path means includes an optical fiber cable.

11. The laser measurement apparatus according to claim 3, wherein the optical path means includes an optical fiber cable.

12. The laser measurement apparatus according to claim 4, wherein the optical path means includes an optical fiber cable.

13. The laser measurement apparatus according to claim 5, wherein the optical path means includes an optical fiber cable.