Beltronics RX 65 - How Laser Works

How Laser (Udar) Works
Laser speed detection is actually UDAR
(Light Detection and Ranging). UDAR guns
project a
beam of invisible infrared light.
The signal is a series of very short infrared
light energy pulses,
which move, in a
straight line, reflecting off
your car and
returning to the gun. UDAR uses these light
pulses to measure
the distance to a vehicle.
Speed
is then calculated by measuring how
quickly these pulses are reflected given the
known speed of light.
UDAR
(or laser) is a newer technology
and is not as widespread as conventional
radar, therefore, you may
not encounter
laser on a daily basis. And unlike radar
detection, laser detection is
not prone to
false alarms. Because UDAR transmits a
much narrower beam than does radar, it is
much more accurate in its ability to distin-
guish
between targets and is also more
difficult to detect. AS A RESULT, EVEN
TIlE BRIEFEST lASER ALERT SHOUlD
BE TAKEN SERIOUSLY.
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There are limitations to UDAR equip-
ment. UDAR
is much more sensitive to
weather conditions than RADAR, and a
UDARgun's range will
be decreased by
anything affecting visibility such as rain, fog,
or smoke. A UDAR gun cannot operate
through glass
and it must be stationary in
order to get an accurate reading. Because
UDAR must have a clearline
of Sight and is
subject
to cosine error (an inaccuracy,
which increases as the angle between the
gun and the vehicle, increases) police
typically use UDAR
equipment parallel to
the road or from an overpass. UDAR can be
used day or night.