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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 laser, however. Laser is much more sensitive to weather conditions than radar,
and a laser gun's range will be decreased by anything affecting visibility, such as rain, fog or smoke. A
laser gun cannot operate through glass, and it must be stationary to get an accurate reading. Because
laser must have a clear line of sight and is subject to cosine error (an inaccuracy that increases as the
angle between the gun and the vehicle increases), police typically use laser equipment parallel to the
road or from an overpass. Laser can be used day or night.
How TSR Works
PASSPORT Max includes a new boost in anti-falsing software to eliminate excessive alerts from
erroneous X and K band sources, such as traffic flow monitoring systems. These systems, which are
becoming more widely used in several countries, generate K band signals to measure the flow of traffic
on a given road. Unfortunately, most detectors see this as a real threat and will alert you to it
unnecessarily. Our new proprietary software—TSR—intelligently sorts, ranks and rejects these types of
false alarms automatically. The result is ultimate protection without excessive false alarms.
How Red Light Cameras Work
Red light cameras use three basic things: a camera, a device to trigger the camera and a computer. An
intersection may have more than one camera to monitor traffic from multiple directions. The trigger is
typically a series of wires buried just beneath the surface of the road. These wires are separated by a
pre‐set distance to create a magnetic field or induction loop. Once a vehicle is in the intersection, the
loop or circuit becomes closed and alerts the computer to take a picture.
In some states, tickets are issued to the car's owner, no matter who's actually driving. In this case, the
red light camera only needs to photograph the vehicle's rear license plate. In other states, the actual
driver is responsible for paying the ticket. In this case, the system needs a second camera in front of the
car to get a shot of the driver's face.
How Speed Cameras Work
There are several types of fixed‐position speed cameras used, including radar, laser, induction‐loop and
photo‐based. Radar‐ and laser‐based cameras are typically mounted near the road and transmit a
short‐range signal across the lanes monitored. Since this signal is transmitted across the road instead of
down the road like with many handheld systems, detecting them in time is critical.
Another technology used is an induction‐loop system. This type of system utilizes wires buried just
beneath the surface of the road to trigger a computer that calculates speed between the two points.
Photo‐based systems take two sets of pictures of all passing vehicles between two separate fixed
locations. Both sets of photographs are date and time stamped, which enables the system to calculate
average speed between the two locations.
Fixed‐speed cameras can also be set up to monitor one to four lanes of traffic in the same direction. To
achieve this, a sensor is installed in each lane, and a wide‐angle camera lens is used to photograph the
vehicle that is speeding.
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