ANALYSIS OF GEOMETRIC DEVIATION FEATURE INDUCED BY THE FDK FOR COMPUTED TOMOGRAPHY MEASUREMENTS |
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| Lin Xue, Hiromasa Suzuki, Yutaka Ohtake, Hiroyuki Fujimoto, Makoto Abe, Osamu Sato, Toshiuuki Takatsuji |
- Abstract:
- Recently, due to the ability to precisely measure inner and outer structure of a specimen in one single scan, X-ray computed tomography (CT) has entered the field of dimensional metrology in industry. Unfortunately, it is very difficult to realize industrial-level accuracy with CT for various factors. In this paper we analyze one of the most serious effects, the FDK (Feldkamp–Davis–Kress) effect, which can be observed in most of the common X-ray CT scanners with a cone beam. The FDK is the well-know reconstruction algorithm widely accepted as a standard reconstruction method for cone beam type of CT. However, this algorithm merely provides an approximate result, for the large dimension specimen, the FDK effect on measurement result is severe. Therefore, we aim at improving measurement accuracy by analyzing the geometric deviation induced by the single FDK effect. We conducted quantitative analysis on the FDK effect using numerical phantoms of the sphere and hole plate that are standard specimen for dimensional CT measurements. After discussing the cause of the FDK effect and the deviation distribution feature on different spatial positions for the chosen numerical phantoms, an improvement strategy of measurement accuracy is proposed.
- Keywords:
- X-ray computed tomography, measurement accuracy, FDK, geometric deviation
- Download:
- IMEKO-TC14-2014-35.pdf
- DOI:
- -
- Event details
- IMEKO TC:
- TC14
- Event name:
- TC14 LMPMI Symposium 2014
- Title:
11th Symposium on Laser Metrology for Precision Measurement and Inspection in Industry
- Place:
- Tsukuba, JAPAN
- Time:
- 03 September 2014 - 05 September 2014