Table of Contents
Advertisement
36
en | Glossary
Focal Length
The distance from the optical center of the lens to the image of
an object located at an infinite distance from the lens. Long
focal lengths give a small field of view (e.g. telephoto effect),
while short focal lengths give a wide angle view.
Infrared Illumination
Electromagnetic radiation (light) with a longer wavelength than
is visible to the human eye. IR illumination is prominent at dusk
and dawn and in incandescent lamps. IR illuminators come in
the form of lamps with the appropriate filters, LEDs, or lasers.
CCD sensors are less sensitive to IR than visible light, but IR
can significantly increase the total illumination level, leading to
a much better image at low light levels.
IRE (Institute of Radio Engineers)
A measurement of video amplitude that divides the area from
the bottom of sync to peak white level into 140 equal units -
140 IRE equals 1V peak-to-peak. The range of active video is
100 IRE.
Lens wizard
The lens wizard is used when setting the backfocus. It opens
the iris fully while maintaining the correct video level using AES.
Lux
The international (SI) unit of measurement of the intensity of
light. It is equal to the illumination of a surface one meter away
from a single candle.
OSD
On-screen Display: Menus are shown on the display monitor.
F.01U.163.823 | v1.0 | 2010.01
I
L
O
Installation and Operation manual
Dinion Day/Night Camera
Bosch Security Systems
Advertisement
Table of Contents
