Modulation transfer function measurement method on basis of characteristics of detector of X-ray imaging system

A technique for modulating transfer function and imaging system, which is applied in the fields of biomedical engineering and computer, and can solve the problems of MTF evaluation accuracy and robustness.

Inactive Publication Date: 2014-01-22
TIANJIN UNIV
View PDF5 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

But so far, because the above methods do not make full use of the prior knowledge of the nature of th

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
  • Modulation transfer function measurement method on basis of characteristics of detector of X-ray imaging system
  • Modulation transfer function measurement method on basis of characteristics of detector of X-ray imaging system
  • Modulation transfer function measurement method on basis of characteristics of detector of X-ray imaging system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0029] Aiming at the fitting error problem when the traditional knife-edge method obtains the oversampled ESF curve, the present invention proposes a new method for measuring the modulation transfer function based on the detector characteristics of the X-ray imaging system, and fits the C-spline curve by fusing the prior knowledge of the detector characteristics In this way, an accurate oversampling ESF curve can be constructed, and a more accurate MTF curve can be obtained than the traditional knife-edge measurement method. The present invention will be described in detail below.

[0030] 1ESF oversampling curve acquisition and processing

[0031] Using oversampling technology to reconstruct the ESF, it is necessary to place the knife edge and the detector matrix at a certain inclination angle, and usually keep the inclination angle α between the edge of the instrument and the direction of the digital detector array at 1.5°-7.1° (the corresponding interpolation number is 8-38...

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 belongs to the field of biomedical engineering and a computer and relates to a modulation transfer function measurement method on the basis of the characteristics of a detector of an X-ray imaging system. The modulation transfer function measurement method comprises the following steps of: placing a knife edge testing instrument to enable the knife edge testing instrument to be clung to the detector, enabling an inclination angle to be formed between a knife edge and the sampling direction of the detector and continuously acquiring a plurality of images; carrying out superposition averaging on a plurality of knife edge images, reducing system noise and then carrying out knife edge boundary detection on an averaged knife edge image to obtain a knife edge boundary line; carrying out Hough transform on a knife edge boundary line graph to obtain a knife edge inclination angle alpha and establishing an oversampling ESF (Extended Superframe Format) curve; using a C spline as a regression spline f for carrying out segmentation fitting on the oversampling ESF curve; carrying out differential operation to obtain a line spread function; carrying out Fourier transform on the line spread function and then carrying out modulus acquisition to obtain a modulation transfer function; and carrying out normalization processing. The modulation transfer function measurement method solves the problem of fitting error generated when the oversampling ESF curve is acquired by a knife edge method; and compared with a conventional knife edge measurement method, the modulation transfer function measurement method can obtain a more accurate MTF (Modulation Transfer Function) curve.

Description

Technical field [0001] The invention belongs to the fields of biomedical engineering and computers, and relates to a new method for accurately measuring the modulation transfer function of a digital X-ray imaging system. Background technique [0002] The modulation transfer function (Modulation Transfer Function, MTF) is the transfer function of the modulation degree, which is a quantitative description of the spatial frequency transmission characteristics of the linear image system, and is an important progress in the image evaluation method. Previously, qualitative description indicators, such as image density, contrast, sharpness, resolution, and distortion, were commonly used to evaluate the image quality of imaging systems, but the results were greatly affected by personal subjective factors. In recent years, with the rapid development of digital X-ray imaging technology, MTF as an objective index has become an important image evaluation method that radiographers and re...

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): G01M99/00
Inventor 周仲兴高峰赵会娟张力新朱庆阵
Owner TIANJIN UNIV
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