Multiple axis multipoint non-contact measurement system

• US 7,420,196 B2
• Filed: 02/27/2006
• Issued: 09/02/2008
• Est. Priority Date: 02/14/2006
• Status: Active Grant

• Current Assignee: LMI Technologies Inc.
• Original Assignee: LMI Technologies Inc.
• Inventors: Metcalfe, Leonard, Arden, Terry
• Primary Examiner(s): Epps; Georgia Y.
• Assistant Examiner(s): Sohn; Seung C
• Application Number:
  US11/364,488
• Publication Number:
  US 20070187631A1
• Time in Patent Office: 918 Days
• Field of Search: 250/206.1, 250/559.29, 250/559.31, 250/559.38, 356/602, 356/3.1, 356/3.12
• US Class Current: 250/559.31
• CPC Class Codes: G01B 11/25 by projecting a pattern, e.g. one or more lines, moiré fringes on the object G01B11/255 takes precedence ; image analysis for depth or shape recovery G06T7/50

Abstract

Apparatus for optically measuring a remote object comprises at least one source for projecting a plurality of discrete zones of electromagnetic radiation (for example laser spots) along a projection plane. Imaging apparatus images a plurality of reflections from the remote object. By spatially offsetting the imaging apparatus from the projection plane, easier discrimination and identification of the reflections is made possible.

Claims

1. Optical triangulation apparatus for determining range comprising:

at least one source for projecting along a projection plane a plurality of discrete spots of light onto at least one remote object;

a single two-dimensional array camera for acquiring an image of a plurality of reflections of said spots of light from at least one remote object, said camera being spatially offset from said projection plane;

a look up table of possible locations on said array of said reflections; and

a processor for outputting from said camera data characterizing said image of said plurality of reflections to discriminate between said spots by associating each of said reflections with one of said spots by reference to said possible locations.

2. A method of optically determining the spatial or dimensional characteristics of at least one remote object, comprising:

projecting onto said object a plurality of discrete zones of electromagnetic radiation along a projection plane, said projection plane intersecting at least one surface of said object;

acquiring on a single two-dimensional array an image of a plurality of reflections of said zones from said at least one remote object from a vantage point that is spatially offset from said projection plane;

predetermining a range of possible locations in said image for each of said plurality of reflections; and

discriminating between said reflections by reference to said ranges of possible locations.

3. The method of claim 2 further comprising associating each one of a plurality of said reflections with one of said zones of electromagnetic radiation by reference to the actual location of each of said reflections in said image and said possible locations of each of said reflections.

4. The method of claim 2 or 3 further comprising applying an optical triangulation technique for assessing range to said object.