HF Series Generators
Calibration
CA-1036R2
52
3. Adjust TV Camera gain for 1 volt peak-to-peak composite video output.
4. Select the maximum PPS and Non-ABC mode.
5. Place 2 mm of Copper (or equivalent homogeneous phantom) in the
Collimator Filter Holder.
6. Calculate the value of the optimum radiation (that will give optimum
brightness) usually is 2μR/frame at 9” FOV (for more information refer to
Image System documentation).
Examples:
For 25 frame/second optimum radiation is 3 mR/min.
2 μR/frame x 25 frame/s = 50 μR/s.
50 μR/s x 60 s/min = 3000 μR/min = 3 mR/min.
For 30 frame/second optimum radiation is 3.6 mR/min.
2 μR/frame x 30 frame/s = 60 μR/s.
60 μR/s x 60 s/min = 3600 μR/min = 3.6 mR/min.
The optimum radiation value should be measured at Image Intensifier
Radiation Input. Intensifier grid should be removed, if it can not be
removed, this value should be multiplied by two or by the value specified
as Grid Absorption Factor.
7. Make a Fluoro exposure at 70 kV and measure the radiation. Optimum
radiation is obtained by modifying the Fluoro kV or the Copper thickness
in the Collimator Filter Holder. First modify the Fluoro kV, if it is more than
80 kV or less than 60 kV modify the Copper thickness in 0.1 mm (or
0.2 mm). Note the value of Fluoro KV and Copper thickness used to
obtain the optimum radiation.
Radiation increases when kV is increased or Copper thickness is
reduced.
Note .
To Next Page
Loading...