17 terms

chapter 8

a substance that is easily penetrated by the xray beam
radiation from the cassette back and cassette tray that is directed back toward the film
film/screen contact
the tightly pressing of the intensifying screen against the film when the cassette is closed
as phosphers glow, giving off light when exposed to xrays
fluorescent crystals in the surface of an intensifying screen
screen speed
the effiency of a screen in converting xrays to light
rare earth phosphors
crystals containing either gadolinium, lanthanum, or yttrium
unwanted marks or images on the radiograph
spectral emission
the color of light emitted by a phospher
silver halide
silver salts of the halogen elements that are mixed with gelatin to form the film emulsion
spectral sensitivity
the portion of the electromagnetic spectrum to which the the film is most sensitive
sensitometric curve
an s shaped curve that demonstraiong the the response of a film to a full range of exposure
the maximum density on a sensitomatic curve
optical density (OD)
a numerical representation of the films ability transmit light
base + fog density
the measue of light absorbed by the film base plus any fog exposure to the film before processing
the term used to describe the range of densities that can be recorded on an xray film
straight-line portion
the portion of the graph that is in a realativity straight, vertical position and indicates film speed