Apparatus and methods for calibrating a laser projection device

• US 20070024810A1
• Filed: 07/27/2005
• Published: 02/01/2007
• Est. Priority Date: 07/27/2005
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Ashford, Curtis
• Granted Patent: US 7,489,411 B2
• Time in Patent Office: Days
• US Class Current: 353/29
• CPC Class Codes: G01C 25/00 Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass testing, calibrating or compensating compasses G01C17/38
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 7/4972 Alignment of sensor

Abstract

An apparatus for calibrating a laser projection device can be used to establish the deviation of known measurement points from an approved digital model or reference condition. The apparatus includes a target having a reflective portion and a mask surrounding the reflective portion. The mask includes a material that changes appearance when excited by a laser. This target eliminates or minimizes user subjectivity in laser projection calibration.

Claims

1. An apparatus for use with a laser projection device, the apparatus comprising a target having a reflective portion and a mask surrounding the reflective portion;

the mask comprising a material that changes appearance when excited by a laser.

2. The apparatus of claim 1, wherein the material fluoresces when excited by a laser from the laser projection device.

3. The apparatus of claim 1, wherein the mask comprises at least one annular area surrounding the reflective portion, the at least one annular area configured to indicate a positioning error when excited by the laser.

4. The apparatus of claim 1, wherein the material is excited by a beam from the projection device that is not centered on the reflective portion.

5. The apparatus of claim 1, further comprising a calibration wall on which the target may be mounted and moved, the wall further configured to provide a measurement of the target movement.

6. The apparatus of claim 1, wherein a color change in the material caused by a laser from the projection device indicates a direction in which to reposition the laser.

7. The apparatus of claim 1, wherein the mask covers a portion of the target while exposing the reflective portion.

8. A method of using a laser projection device relative to an article, the method comprising:

positioning the laser projection device and one or more targets relative to the article;

projecting a laser from the projection device toward one of the one or more targets; and

if the beam changes an appearance of a material surrounding a reflective portion of the one target, repositioning at least one of the one target and the laser.

9. The method of claim 8, further comprising using fluorescence of the material to determine whether the laser projection device is projecting within a predetermined tolerance.

10. The method of claim 8, wherein the article includes a calibration wall.

11. The method of claim 10, wherein the one target is repositioned, the method further comprising adjusting a positional coordinate for the repositioned target for use by the laser projection device to reflect the repositioning.

12. The method of claim 8, further comprising repositioning the one target based on a color change in the mask.

13. The method of claim 8, further comprising operating a micrometer of a target positioning stage to reposition the one target.

14. A laser projection system comprising:

a laser projection device;

a plurality of targets for use with the laser projection device; and

a calibration wall having a wall surface and a plurality of target positioning stages affixed to the wall surface, each positioning stage configured to receive a target and operable to reposition the received target relative to the wall surface.

15. The system of claim 14, wherein at least one of the targets comprises:

a central reflective portion; and

a mask that covers part of the target to define the central reflective portion;

the mask comprising a fluorescent material excitable by a laser from the laser projection device.

16. The system of claim 15, wherein the material comprises at least one annular area surrounding the central reflective portion, each annular area having a diameter configured to indicate a positioning error by the laser.

17. The system of claim 16, wherein at least one of the annular areas is excited when a laser from the projection device is not centered on the central reflective portion.

18. The system of claim 15, wherein the material is excited by a laser from the projection device that is not centered on the central reflective portion.

19. The system of claim 15, wherein the central reflective portion and mask define an essentially flat surface of the at least one target.

20. The system of claim 14, wherein a color change in the target caused by a beam from the projection device indicates a direction in which to reposition the laser.