Measurement of wiener spectrum of radiographic screen-film systems
A method to measure the Wiener spectrum of radiographic screen-film systems in a hospital setting is presented. Radiographs exposed to uniform X-rays are scanned by a microdensitometer, and optical density fluctuation data about the mean density are obtained by subtracting the mean density from the...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Penerbit UTM Press
2001
|
| Subjects: | |
| Online Access: | http://eprints.utm.my/882/ http://eprints.utm.my/882/1/JT34C5.pdf |
| _version_ | 1848890018786967552 |
|---|---|
| author | Wan Hassan, Wan Muhamad Saridan |
| author_facet | Wan Hassan, Wan Muhamad Saridan |
| author_sort | Wan Hassan, Wan Muhamad Saridan |
| building | UTeM Institutional Repository |
| collection | Online Access |
| description | A method to measure the Wiener spectrum of radiographic screen-film systems in a hospital setting is presented. Radiographs exposed to uniform X-rays are scanned by a microdensitometer, and optical density fluctuation data about the mean density are obtained by subtracting the mean density from the density values. The data are low-pass-filtered by averaging pairs of pixels, followed by low-frequency filtering to eliminate very low-frequency components. A slit trace is synthesised by averaging adjacent traces and the trace is segmented to segments of 256 data points per segment with overlap of 128 data points. Data in each segment are windowed and fast Fourier transformed. The Fourier coefficients are squared and normalized to obtain the power spectrum. On site measurement for Lanex Regular and Lanex Fine screens gives results that are comparable with published data. |
| first_indexed | 2025-11-15T20:35:24Z |
| format | Article |
| id | utm-882 |
| institution | Universiti Teknologi Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-15T20:35:24Z |
| publishDate | 2001 |
| publisher | Penerbit UTM Press |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | utm-8822017-11-01T04:17:51Z http://eprints.utm.my/882/ Measurement of wiener spectrum of radiographic screen-film systems Wan Hassan, Wan Muhamad Saridan QC Physics A method to measure the Wiener spectrum of radiographic screen-film systems in a hospital setting is presented. Radiographs exposed to uniform X-rays are scanned by a microdensitometer, and optical density fluctuation data about the mean density are obtained by subtracting the mean density from the density values. The data are low-pass-filtered by averaging pairs of pixels, followed by low-frequency filtering to eliminate very low-frequency components. A slit trace is synthesised by averaging adjacent traces and the trace is segmented to segments of 256 data points per segment with overlap of 128 data points. Data in each segment are windowed and fast Fourier transformed. The Fourier coefficients are squared and normalized to obtain the power spectrum. On site measurement for Lanex Regular and Lanex Fine screens gives results that are comparable with published data. Penerbit UTM Press 2001-06 Article PeerReviewed application/pdf en http://eprints.utm.my/882/1/JT34C5.pdf Wan Hassan, Wan Muhamad Saridan (2001) Measurement of wiener spectrum of radiographic screen-film systems. Jurnal Teknologi C (34C). pp. 35-42. ISSN 0127-9696 http://www.penerbit.utm.my/onlinejournal/34/C/JT34C5.pdf |
| spellingShingle | QC Physics Wan Hassan, Wan Muhamad Saridan Measurement of wiener spectrum of radiographic screen-film systems |
| title | Measurement of wiener spectrum of radiographic screen-film systems |
| title_full | Measurement of wiener spectrum of radiographic screen-film systems |
| title_fullStr | Measurement of wiener spectrum of radiographic screen-film systems |
| title_full_unstemmed | Measurement of wiener spectrum of radiographic screen-film systems |
| title_short | Measurement of wiener spectrum of radiographic screen-film systems |
| title_sort | measurement of wiener spectrum of radiographic screen-film systems |
| topic | QC Physics |
| url | http://eprints.utm.my/882/ http://eprints.utm.my/882/ http://eprints.utm.my/882/1/JT34C5.pdf |