Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Three-dimensional measurement method based on pulse width modulation fringe

A technology of pulse width modulation and three-dimensional measurement, which is applied in the direction of measuring devices, instruments, and optical devices, etc., can solve the problems of restricting the measurement speed, achieve fast measurement speed, less reduction in fringe contrast, and overcome the effect of measurement depth

Active Publication Date: 2015-12-16
SHANGHAI SUPORE INSTR
View PDF7 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In terms of fringe type, because the traditional sinusoidal fringe is an 8-bit grayscale image, its grayscale value is distributed between 0-255, and the projection speed is limited within 120HZ, which restricts the measurement speed; in terms of electronic equipment properties, Since today's three-dimensional measurement systems are all fringes with characteristic information projected by DLP, the measurement error caused by the high-order harmonics caused by the nonlinear gamma effect of electronic equipment is an inevitable problem

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Three-dimensional measurement method based on pulse width modulation fringe
  • Three-dimensional measurement method based on pulse width modulation fringe
  • Three-dimensional measurement method based on pulse width modulation fringe

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0018] The embodiments of the present invention will be described in further detail below in conjunction with the accompanying drawings, but the present embodiments are not intended to limit the present invention, and any similar structures and similar changes of the present invention should be included in the protection scope of the present invention.

[0019] A three-dimensional measurement method based on pulse width modulation fringes, comprising the following steps:

[0020] (1) Encoding of pulse stripes.

[0021] a. An ideal sine wave with a four-step phase shift function is generated by a computer:

[0022] (2)

[0023] Among them, T is the number of cycles, y is the pixel of the sine wave, s is the step size, and m is the number of phase shift steps (=1,2,3,4). Such as figure 2 As shown by the red line in (a), the phase-shifted sine wave with a cycle number of 1 and a phase shift step of 1, the frequency is recorded as f s .

[0024] b. Generate a set of trapez...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a three-dimensional measurement method based on a pulse width modulation fringe. The three-dimensional measurement method consists of three key parts of pulse fringe encoding, pulse fringe defocusing and three-dimensional reconstructing. A pulse fringe is generated from a computer and then moderately defocused through a projector to generate a sine fringe on a reference face for three-dimensional measurement. The invention is advantageous in that (1) as the pulse fringe is a binary fringe, the grayscale value thereof can only be two values (0 and 1), so the measurement is quick; (2) since the nonlinear gamma of the projector can be eliminated simply by slight defocusing the projector, phase errors can be reduced without complex nonlinear calibration; and (3) thanks to less reduction in fringe contrast after the pulse fringe is slightly defocused, the measurement depth problem is overcome.

Description

technical field [0001] The invention relates to an optical three-dimensional measurement method, which belongs to the technical field of photoelectric detection. In particular, it relates to a three-dimensional measurement method based on pulse width modulated fringes. Background technique [0002] With the intersecting and multi-integrated development of science and technology, the three-dimensional measurement method based on optics, electricity, image processing and computer vision has become an industrial non-destructive testing method with broad application prospects. The structured light three-dimensional measurement system formed by this method has been widely used in many fields such as industrial manufacturing, cultural relics protection, medical treatment, etc. play an important role. In order to meet the fast pace of production and life, three-dimensional measurement speed has become an important index to measure the measurement system; at the same time, with th...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G01B11/25
Inventor 伏燕军李彪曾灼环
Owner SHANGHAI SUPORE INSTR
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com