Target LRC 100, Руководство пользователя

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How does a laser gun work?
A laser gun uses infra-red (invisible) laser light that func-
tions best when it is aimed at optimum
reflecting components such as the licence plate or the
headlamps. The computer, that forms an integral part of
the laser gun, calculates the time that the emitted laser
beam takes before it is returned and subsequently
displays the speed of the vehicle at which it is aimed.
On average, a laser gun emits approximately 100 separate
pulses in the 0.3 second that is necessary in order to
determine the speed of a vehicle. In contrast with radar
measurements, a laser gun can pick out a particular
vehicle from a group with considerable accuracy (see
figure 1). At a distance of 300 metres the width of the
beam is approximately 1 metre. A radar beam is many
times wider (see figure 2).
How does a laser detector work?
Laser detectors that can be mounted behind the
windscreen provide little or no protection against laser
guns because in most cases, they only detect the laser
beam when it is aimed at the vehicle. If a laser detector
nevertheless gives an alarm, it will be too late to apply
the brakes because the laser gun will already have
established the speed of the vehicle.
Aan what does the TARGET LRC 100 do
in this case?
The Target LRC 100 is an active laser detector. The recei-
ver part (the infra-red photo diode), is so adjusted that
no false alarms can occur. However, as soon as a laser gun
is aimed at your vehicle the system comes into operation.
In that case the TARGET LRC 100 emits a signal with a
duration of 7 seconds that will be picked up by the laser
gun. At the same time you will be warned by the
light/sound signals on the display in the vehicle. During
this 7 second period, the laser gun cannot establish the
speed of your vehicle and you have sufficient time in
which to check, and if necessary reduce your speed. After
a transmission session of 7 seconds the system functions
only as detector for the next 60 seconds (you will then
be warned when your vehicle is being shot with a laser
gun but the system will not transmit a
figure 1
figure 2
230089 LRC 100 Handl EN 04-03-2003 13:20 Pagina 4