Converting a digital radiograph to an absolute thickness map

US7480363B2 · kind B2 · utility

Assignee

• GE Betz, Inc. · US

Inventors

• Brian Lasiuk · Niskayuna, US
• Thomas J. Batzinger · Burnt Hills, US
• Manoharan Venugopal · Bengaluru, IN
• Elizabeth Dixon · Newmarket, GB
• Michael Robert Hopple · Schenectady, US
• Nityanand Gopalika · Supaul, IN
• Sivaramanivas Ramaswamy · Kanchinakote, IN
• Debasish Mishra · Bengaluru, IN
• Rajashekar Venkatachalam · Bengaluru, IN
• Vamishi Krishna Reddy Kommareddy · Bengaluru, IN

Key dates

• Filing date: Apr 18, 2005
• Grant date: Jan 20, 2009
• Expiry date: Feb 8, 2026

Classification

• Technology area (CPC G): Physics
• CPC primary: G01B15/025
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A digital radiography imaging system for acquiring digital images of an object, and a method for transforming digital images into an absolute thickness map characterizing the object under inspection. The system includes a radiation source for directing radiation through a desired region of the object, and a radiation detector having a plurality of sensing elements for detecting radiation passing through the object. Numerical data generated from each sensing element is calibrated, for example by correcting for variations in radiation paths between the source and detector, by correcting for variations in the spatial frequency response (MTF) of the detector, by correcting for variations in the geometric profile of the object under inspection, and by correcting for material contained in and/or around the object. The calibrated data is processed in order to generate and display an absolute thickness map of the object. The calibration procedures are adapted for extracting a thickness map from both isotope sources and X-ray tube sources.