Second experimental measurements with Cyberknife at Birmingham. Green scintillator thin sheet measurements only.
Pre-data Taking Information and Notes
- 200mmx200mmx2mm blue scintillator sheet polystyrene base
- sandwiched by two 200mmx200mmx50mm polystyrene clear plastic blocks
- 565mm from lens to sheet
- Check camera in focus with ruler on the sheet
- Ruler in focus at sheet
- Scintillator blocks aligned to laser cross hairs
- 785 mm source to surface distance suitable for output factor/PDD/profile measurements.
- Wooden box is covered with black cloth
- Camera height adjusted with wooden plates
- Top surfaces of plastic blocks and sheet aligned with paper underneath
- All images taken with
- Canon EOS 1100D
- 18-55mm lens
- 30s exposure
- Beam turned on for a given amount of time within the 30s exposure
- This is noted in monitor units, with the beam having constant 1000MU/minute
- Used EOS utility app for controlling camera
- Image of ruler taken at sheet for pixels to mm conversion
- 3 images taken at each collimator size with 1 background image each.
|Collimator Size (mm)||Monitor Units||With sheet||No sheet|
Before and after irradiation
Green discolouration observed after irradiation. Only present when the lights are on