Nikon Camera N90 - Manual (Page 224)

GLOSSARY___________________________
Balanced fill-flash operation
A technique in flash photography in which flash illumination is
controlled to balance it with the ambient light on the scene. The
N90 uses an Automatic Balanced Fill-Flash System with TTL
Multi-Senosr for this automatic operation with a compatible
Nikon TTL Speedlight.
Continuous Servo AF
Focus detection continues for as long as the shutter release
button is lightly pressed and the reflex mirror is in the viewing
position. Useful when camera-to-subject distance is likely to
change.
CPU
Central Processing Unit. The electronic component which
controls an electronic product's functions.
AF Nikkor (including AF-D Nikkor) and Al-P-Nikkor lenses have
built-in CPUs.
Depth of field
The zone of sharpest focus in front of, behind and around the
subject on which the lens is focused; can be previewed in the
N90 and some other Nikon cameras
D-type AF Nikkor lenses
AF Nikkor lenses that send to the N90’s microcomputer the
Distance Information used for 3D Matrix Metering or 3D Multi-
Sensor Balanced Fill-Flash (with Nikon SB-25 Speedlight).