Abstract
Full-field digital mammography imaging systems have been investigated extensively. However, most investigations focus on the quality assessment of the entire image. In this article, we present the results of experimental measurements on the position-dependent image characteristics of a CCD array-based digital imaging system. Objective image quality parameters such as noise power spectrum (NPS) and signal-to-noise ratio (SNR), which are also frequency-dependent, are employed for this investigation. The image detector uses 12 CCDs arranged in a 4 × 3 array to cover a field of 18 cm × 24 cm with a single x-ray exposure. Totally 18 sub-areas were chosen as the regions-of-interest (ROIs) for each full-field image to study position-dependent characteristics. Our experimental results indicate that the image quality at different positions of the full-field image exhibit slightly variance due to the characteristic diversity of the CCDs and due to the oblique angle of the ROIs to the x-ray source. The image seams caused by the physical gaps between adjacent CCDs do not increase the noise components significantly to the composite full-field image. The x-ray energy-dependence of NPS and SNR was also studied.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 101-111 |
| Number of pages | 11 |
| Journal | Journal of X-Ray Science and Technology |
| Volume | 9 |
| Issue number | 3-4 |
| State | Published - Dec 1 2001 |
| Externally published | Yes |
Keywords
- Digital radiography
- Full-field mammography systems
- Image quality
- Modulation transfer function
- Noise power spectra
- Signal-to-noise ratio
ASJC Scopus subject areas
- Radiation
- Instrumentation
- Radiology Nuclear Medicine and imaging
- Condensed Matter Physics
- Electrical and Electronic Engineering