TM 5-3610-285-14
GLOSSARY
ABBREVIATION/TERM
DEFINITION
Angstrom Unit( ) . ......................................................... A unit of length equal to one ten-billionth of
a meter. Used to measure the wavelengths of
light.
Cathode . ....................................................................... The negative electrode of a tube or diode.
Densitometer ................................................................. An electric instrument for measuring optical
density or tone. Transmission densitometers
measure the full density range of negatives.
Reflection densitometers measure the reflection
range of opaque copy.
Density .......................................................................... (1) The mass per unit volume of a substance
under specified conditions of pressure and
temperature.
(2) The quantity of metallic silver per unit
area in negatives and positives.
Dynode . ........................................................................ An electrode having the primary function of
supplying secondary-electron emission, for
current amplification, in an electron tube.
Fiber Optics . ................................................................. That branch of optical technology concerned
with the transmission of radiant power through
fibers made of transparent materials such as
glass, fused silica, or plastic.
Flat . .............................................................................. (1) Lithography: The assembly of negatives on
goldenrod paper for contact exposure with a
sensitized plate.
(2) Photography: Lacking in contrast.
Halation . ....................................................................... Blurring of a photographic image because of
light reflection from the film base.
Peel . ............................................................................. Selectively removing the opaque layer from its
film base.
Peel Coat . ..................................................................... A film which produces a peelable negative
directly from a scribed original or film
negative. The peel coat film eliminates the
possibility of misregistration which occurs due
to size variations inherent in photo materials
after processing.
Photomultiplier Tube . .................................................... A phototube with one or more dynodes between
its photocathode and the output electrode.
GLOSSARY-1
