The physics of computed radiography: Measurements of pulse height spectra of photostimulable phosphor screens using prompt luminescence
- Sunnybrook and Women's College Health Sciences Centre, Department of Medical Biophysics, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada)
Computed radiography (CR) is a digital technology that employs reusable photostimulable phosphor (PSP) imaging plates (IP) to acquire radiographic images. In CR, the x-ray attenuation pattern of the imaged object is temporarily stored as a latent charge image within the PSP. The latent image is optically readout as photostimulated luminescence (PSL) when the phosphor is subsequently stimulated using a scanning laser. The multiple stages necessary to create a CR image make it difficult to investigate either experimentally or theoretically. In order to examine the performance of the CR system at a fundamental level separate measurements of the processes involved are desirable. Here pulse height spectroscopy is used to study the prompt violet light emission or prompt luminescence (PL) from commercial PSP screens. Since the mechanism by which light escapes from the phosphor is identical for PL and PSL, observations and conclusions based on the pulse height spectra (PHS) of PL are relevant to the understanding of the behavior of the PSL light emission that outputs the radiographic image in CR. The PL PHS of screens of different thickness and optical properties were measured and compared with the PHS of conventional phosphors. A new method for calibration of the PHS in terms of the absolute number of optical photons per x-ray is introduced and compared to previously established methods.
- OSTI ID:
- 20726858
- Journal Information:
- Medical Physics, Vol. 32, Issue 12; Other Information: DOI: 10.1118/1.2122587; (c) 2005 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-2405
- Country of Publication:
- United States
- Language:
- English
Similar Records
Dose response of BaFBrI:Eu{sup 2+} storage phosphor plates exposed to megavoltage photon beams
The role of activator concentration and precipitate formation on optical and dosimetric properties of KCl:Eu{sup 2+} storage phosphor detectors