what does modulation transfer function (MTF) measure?
the systems ability to transfer object detail into the image
What does DQE stand for?
detective quantum efficiency
Spatial resolution is _____?
recorded detail
what does concave mean?
curved inward.
what does increasing kVp do to receptor exposure (RE)?
increases RE
what does an MTF value of 1 mean?
perfect transfer of detail.
what does DQE measure?
system's ability to convert x-ray intensity into an electronic image.
contrast resolution is ________?
visibility of detail.
what is the main factor in DR?
pixel size/pixel pitch
what does increasing kVp do to beam penetration?
increases the percentage of beam penetration.
what is the maximum possible MTF value?
1, value cannot exceed 1
If FOV increases with a fixed matric size, what happens to pixel size?
pixel size increases.
Size distortion is ______?
magnification
what is pixel pitch?
distance from one pixel to another
what type of factor is kVp?
photographic factor
on exams, what type of MTF value should you choose as "best"?
the value closest to 1 without exceeding it
if matrix size increase, with a fixed FOV, what happens to pixel size?
pixel size decreases.
Shape distortion is _________?
elongation and foreshortening.
what is the main factor that controls receptor exposure (RE)?
mAs
what is:
a 15% increase or decrease in kVp (with other factors constant) will result in a doudling or halving of recepetor exposure.
15% rule
which is the best MTF value?
1. 0.4
2. 0.6
3. 0.8
4. 1.2
3.) 0.8, it is the closest to 1
what is scatter?
a photon
what does convex mean?
curved outward
in regard to DEL fill factor, what percent is active versus non-active?
80% active, 20% non-active
within what kVp range is the 15% rule most effective?
60-90 kVp