Portable Structured Light Measurement Module/Apparatus with Pattern Shifting Device Incorporating a Fixed-pattern Optic for Illuminating a Subject-under-test

• US 20130188012A1
• Filed: 07/26/2012
• Published: 07/25/2013
• Est. Priority Date: 07/26/2011
• Status: Active Grant

• Current Assignee: Seikowave Health Solutions, Inc. (Seikowave, Inc.)
• Original Assignee: Seikowave, Inc.
• Inventors: BELLIS, Matthew W., Lau, Daniel L., Hara, Hideo
• Granted Patent: US 9,444,981 B2
• Time in Patent Office: Days
• US Class Current: 348/42
• CPC Class Codes: H04N 23/50 Constructional details
• CPC Class Codes: H04N 23/51 Housings
• CPC Class Codes: H04N 23/555 for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes

Abstract

A surface measurement module for 3-D image acquisition of a subject-under-inspection. The module having: (a) a casing to house a pattern shifting device having a fixed-pattern optic through which light from a light source is passed, an output of the pattern shifting device being directed at a polarizing beam splitter and the polarized output of the splitter directed through a lens assembly comprising at least one lens element; (b) a reflector to direct the polarized output exiting the lens assembly, to illuminate a surface of the subject-under-inspection; (c) a scattered light illumination off the surface is directed back through the lens assembly for capture by an image sensor; and (d) the casing also housing the polarizing beam splitter, the lens assembly, and the image sensor. The output of the fixed-pattern optic comprises a multi-frequency pattern. The pattern shifting device may be a linear or rotating type.

Claims

1. A surface measurement module for 3-D image acquisition of a subject-under-inspection, the module comprising:

(a) a casing to house a pattern shifting device having a fixed-pattern optic through which light from a light source is passed, an output of said pattern shifting device being directed at a polarizing beam splitter and the polarized output of said splitter directed through a lens assembly comprising at least one lens element;

(b) a reflector to direct said polarized output exiting said lens assembly, to illuminate a surface of the subject-under-inspection;

(c) a scattered light illumination off said surface is directed back through said lens assembly for capture by an image sensor; and

(d) said casing also housing said polarizing beam splitter, said lens assembly, and said image sensor.

2. The surface measurement module of claim 1 wherein:

(a) said output of said pattern shifting device comprises a multi-frequency pattern comprising a plurality of pixels representing at least a first and second superimposed sinusoid projected simultaneously; and

(b) each of the sinusoids represented by the pixels have a unique temporal frequency and each of the pixels projected to satisfy

3. The surface measurement module of claim 1 further comprising:

(a) a quarter-wave plate interposed between said surface of the subject-under-inspection and a pathway directed to said lens assembly; and

(b) a plurality of images captured of said scattered light illumination, after passing back through said lens assembly, off said surface being used for the 3-D image acquisition.