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

Structured light coding method based on wrapped phase forward and reverse

A technology that wraps phase and encoding methods, applied in the field of optical three-dimensional shape measurement, can solve problems such as limiting measurement applications, achieve the effects of reducing the number of images, improving efficiency, and greatly practical potential

Pending Publication Date: 2021-04-06
CHONGQING UNIV
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Faced with the modern industry pursuing higher and higher measurement speeds, there are still some problems in the phase shift measurement profilometry. In order to obtain the phase information of the measured object, it is usually necessary to project 9 grating images (three-frequency 3 step method), in which what really needs to be unfolded is the wrapping phase at the highest frequency, and the rest of the images are only projected to understand the wrapping phase, a large number of images to be projected limits the application of phase shift measurement profilometry in high-speed, real-time environments in modern industries measurement application

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
  • Structured light coding method based on wrapped phase forward and reverse
  • Structured light coding method based on wrapped phase forward and reverse
  • Structured light coding method based on wrapped phase forward and reverse

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] This embodiment discloses a structured light encoding method based on the positive and negative wrapping phases. Taking the three-step phase shift method, 16 fringe periods, and De Bruyne sequence as an example, it includes the following steps:

[0035] 1) see figure 1 and figure 2 , to build a structured light measurement system. The structured light measurement system includes a computer 1 , a camera 2 , a projector 3 and a measured object 4 . The camera 2 and the projector 3 are communicably connected to the computer 1 . The camera 2 and the projector 3 are respectively arranged on the front side of the measured object 4, and the arrangement of the structured light measurement system should ensure that the common field of view of the projector 3 and the camera 1 is sufficiently large, and the measured object's measured Features should be covered by the raster projected by this projector 3 . In this embodiment, the optical axes of the projector 3 and the camera 2...

Embodiment 2

[0052] This embodiment provides a relatively basic implementation method, a structured light encoding method based on the positive and negative wrapped phases, taking the three-step phase shift method, 16 fringe periods, and De Bruyne sequence as examples, including the following steps:

[0053] 1) see figure 1 and figure 2 , to build a structured light measurement system. The structured light measurement system includes a computer 1 , a camera 2 , a projector 3 and a measured object 4 . The camera 2 and the projector 3 are communicably connected to the computer 1 . The camera 2 and the projector 3 are respectively arranged on the front side of the measured object 4, and the arrangement of the structured light measurement system should ensure that the common field of view of the projector 3 and the camera 1 is sufficiently large, and the measured object's measured Features should be covered by the raster projected by this projector 3 . In this embodiment, the optical axes...

Embodiment 3

[0066] The main steps of this embodiment are the same as those in Embodiment 2. Further, in step 4), during the process of the computer 1 synthesizing three phase-shifted projection images that contain positive and negative sequence information, the computer 1 compares 0 codes with 1 code, design the corresponding 0 stripe and 1 stripe for each phase shift stripe in the three-step phase shift, and the specific stripe form of each level is as follows:

[0067]

[0068] In formula (2), where n=1,2,3, corresponding to each step of the phase shift image in the three-step phase shift, A is the DC component, B is the amplitude, W 0 is the pixel width (unit) occupied by each level of stripes, and Wherein, W is the width that projector 3 projects a single image, and T is the fringe cycle number, (x 0 ,y 0 ) is the pixel coordinates in the single-level stripe, is the phase shift step size, and the phase shift step size is

[0069] Design the projected grating image according...

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 structured light coding method based on wrapped phase forward and reverse. The method comprises the following steps: 1) constructing a structured light measurement system; 2) adjusting the positions of a camera and a projector, and storing calibration parameters; 3) generating a random positive and negative sequence to be used; 4) synthesizing three phase shift projection images containing positive and negative sequence information according to the generated sequence; 5) outputting the three phase shift projection images to the surface of the measured object, and collecting three stripe grating images after the surface of the measured object is modulated and deformed; 6) carrying out phase unwrapping on the three stripe grating images to obtain an initial wrapping phase; 7) adjusting the initial wrapping phase to obtain an adjusted wrapping phase and a period number; 8) calculating a full-field phase, and carrying out three-dimensional reconstruction; the method is suitable for most traditional phase shift profilometry, and the number of images needed by projection is greatly reduced under the condition that the precision, advantages and experiment requirements of an original method are reserved.

Description

technical field [0001] The invention belongs to the technical field of optical three-dimensional shape measurement, and in particular relates to a structured light encoding method based on positive and negative wrapped phases. Background technique [0002] With the continuous development of modern science and technology, with the increasing demand for detection objects in the industry, how to realize the intelligent, high-speed and high-precision measurement of the measured object is a technical problem that needs to be solved urgently at this stage. In order to solve this problem, many different types of three-dimensional measurement technologies were born, and have been widely used in fields such as industrial assembly line product size detection, reverse engineering, and virtual reality. [0003] Three-dimensional measurement technology can be divided into contact type and non-contact type according to whether it is in contact with the measured object. Compared with cont...

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): G01B11/00G01B11/25
CPCG01B11/002G01B11/254
Inventor 刘飞李文博黄瀚霖杨恬杨炀贺仁智贾文超傅渤雅袁依琳
Owner CHONGQING UNIV
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