Radiography Essentials Vocab Ch. 11 P. 1

Air Gap
A space between the patient and the film.
Radiation directed back toward the x-ray tube.
A moving grid.
Coherent Scattering
This type of interaction takes place at relatively low energy levels (below 10 keV) and causes and effect similar to ricochet. Also known as Thompson Scatter.
Compton Effect
The incoming x-ray photon collides with an outer shell electron removing it from the atom.
Crosshatch Grid
A composite of two grids with the lead strips at right angles to each other.
Focal Range
The distance within which the grid will not absorb an undue amount of useful radiation.
Focused Grids
Grids with lead strips aligned to the direction of the diverging primary x-ray beam.
A device placed between the patient and the film.
Grid Cassettes
Special cassettes with a grid built into the front side.