Method for quickly identifying and focusing target object with interferents in digital holography

A technology of digital holography and focusing method, which is applied in the field of image recognition, can solve the problems that the precise focusing distance of the object to be measured cannot be accurately obtained, and the focusing curve does not have a single peak maximum value, so as to eliminate the influence of focusing distance discrimination and reduce the Calculation time, the effect of improving calculation speed

Active Publication Date: 2020-01-10
HARBIN INST OF TECH
View PDF10 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to: in the prior art, the focus curve obtained by using the traditional operation method under the condition of the presence of interference objects for the specific target object known to be measured does not have the characteristic of the single peak value, and cannot accurately obtain the target object to be measured. For the problem of the precise focus distance of the target, a method for fast identification and focus of the target with interference in digital holography is proposed

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
  • Method for quickly identifying and focusing target object with interferents in digital holography
  • Method for quickly identifying and focusing target object with interferents in digital holography
  • Method for quickly identifying and focusing target object with interferents in digital holography

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach 1

[0035] Specific implementation mode 1: This implementation mode will be described in detail with reference to the figure. The method for fast identification and focusing of a target object with disturbing objects in digital holography described in this implementation mode includes the following steps:

[0036] Step 1: using the off-axis digital holography method to collect a target hologram containing interfering objects;

[0037] Step 2: Perform Fourier transform on the hologram and intercept the object spectrum G(u,v) to be reproduced;

[0038] Step 3: Take the complex conjugate of the reference object f(x,y) for Fourier transform to obtain F * (u,v);

[0039] Step 4: Set the initial focus range[d min , d max ], current interval calculation times N and focus accuracy;

[0040] Step 5: Use the angle spectrum reconstruction algorithm to calculate the reproduction phenomenon at N positions within the focus range

[0041] Step 6: Calculate the correlation peak using the m...

Embodiment

[0057] Combine below Figure 2 to Figure 4 and the specific embodiments further describe the present invention in detail. It should be noted that the specific embodiments described here are only used to explain the present invention, not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not constitute a conflict with each other.

[0058] In the simulation, Daphnia is set as the target to be detected, and the distance from the CCD receiving surface is 9.05cm. The "star" and "cross" are placed on both sides of the target as interference targets, and the distance from the receiving surface is 8.05cm and 10.05cm respectively , its schematic diagram is as figure 2 shown. Set the focus range to 5.00-13.00cm. For comparison, use the standard deviation contrast criterion function based on high-frequency components to search for the focu...

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 method for quickly identifying and focusing a target object with interferents in digital holography, and relates to the technical field of image recognition. The objective ofthe invention is to solve the problem that in the prior art, a focusing curve obtained by using a traditional operation method for a known specific target object in the presence of an interferent does not have the characteristic of a single peak maximum value. According to the method, an optical correlation method is used for identifying and focusing the target object, so that a more accurate focusing position can be obtained, and a focusing curve has a single-peak maximum value characteristic. The influence of non-target objects at different positions on a measurement light beam path on focusing distance discrimination can be effectively avoided by utilizing an optical correlation identification method. The bisection method is used to gradually reduce the search interval of calculation,the calculation time of the focusing discrimination process is effectively reduced, and the focusing position of the to-be-measured target object can be rapidly determined.

Description

technical field [0001] The invention relates to the technical field of image recognition, in particular to a method for rapid identification and focusing of a target object with disturbing objects in digital holography. Background technique [0002] With the development of electronic technology and digital technology, traditional holography is gradually replaced by digital holography. At present, digital holographic measurement technology has been widely used as an important way to realize optical measurement. After the hologram containing the target information is obtained through the receiver, the relevant information of the target can be obtained after processing by the computer, such as the shape, size and position of the target, etc., and the dynamic change of the target can be judged by collecting the information of the target process. In computer processing, the digital holographic reconstruction algorithm is used to reconstruct the target object. Different reconstr...

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
Patent Type & Authority Applications(China)
IPC IPC(8): G06T7/00G03H1/00G03H1/04
CPCG06T7/0002G03H1/0005G03H1/0443G06T2207/20056G03H2001/0033
Inventor 张华俊张宇姚金任任明源
Owner HARBIN INST OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap