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How Laser (Lidar) Works
Laser speed detection is actually LIDAR
(Light Detection and Ranging). LIDAR 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. LIDAR 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.
LIDAR (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 LIDAR transmits a
much narrower beam than does radar, it is
much more accurate in its ability to
distinguish between targets and is also
more difficult to detect.
AS A RESULT,
EVEN THE BRIEFEST LASER ALERT
SHOULD BE TAKEN SERIOUSLY.
There are limitations to LIDAR
equipment. LIDAR is much more sensitive
to weather conditions than RADAR, and a
LIDAR gun’s range will be decreased by
anything affecting visibility such as rain, fog,
or smoke. A LIDAR gun cannot operate
through glass and it must be stationary in
order to get an accurate reading.
Because LIDAR must have a clear line
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 LIDAR equipment
parallel to the road or from an overpass.
LIDAR can be used day or night.
How Laser Works
How TSR Works
Some of the markets where these
sensors are located include:
Omaha NE
Raleigh-Durham NC
San Francisco CA
San Jose CA
Santa Barbara CA
Ventura CA
Washington DC
Dayton OH
Denver CO
Everett WA
Lincoln NE
New York NY
Oakland CA
Olympia WA
Our exclusive TSR anti-falsing software
rejects these unwanted signals. Since not all
markets have this type of traffic flow
system, your detector has been pre-set with
TSR turned off.
To turn TSR on, simply visit the
Preferences section. Under “Bands”, select
TSR “on”.
How TSR Works
Several manufacturers of traffic flow
monitoring systems use K-band
transmitters to sense traffic movement.
Unfortunately these sensors are
transmitting in an “instant on” mode, which
creates a false alert. These sensors are
positioned approximately 1 mile apart and
turn on and off approximately every
minute.
These sensors are fully self-contained
and roadside-mounted.