Laser Atlanta SpeedLaser R, Руководство пользователя

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3) Range (Chronometer) Accuracy Test
The SpeedLaser
®
hardware ONLY measures Time. Range and
Speed are computed values derived from multiple time
measurements by the firmware, which was checked for proper
operation during BIT. The design of the firmware was verified as
part of the IACP certification process.
This test uses the SpeedLaser
®
’s high-speed chronometer (timer) to
measure the time it takes a light pulse to travel a know distance (i.e.;
from the SpeedLaser
®
to a target at a known distance and back).
Since the speed of light in air is known, the SpeedLaser
®
can
calculate the range that the light pulse traveled. The operator then
compares the reported range to the known distance to the target. To
verify that the timing hardware is working correctly the computed
range must match the known distance to within
±
1 foot (25 cm). At
least two such comparisons using targets at least twenty (20) feet
apart must be made.
In normal operation, the SpeedLaser
®
measures the time it takes for a
light pulse to travel from the SpeedLaser
®
to a moving vehicle and
back. The SpeedLaser
®
makes hundreds of such round trip time
measurements each second, each time measurement is converted to a
range and stored. When the SpeedLaser
®
has sufficient stored
ranges, it performs a linear regression calculation that yields the
speed of the vehicle. Numerous firmware filters are used to confirm
the computed speed before it is displayed.
4) Horizontal Sight Alignment Test
This is a test to confirm that the sighting system and the invisible
light pulse emitted by the SpeedLaser
®
are aligned horizontally. The
operator uses the sighting system to aim at an object and then
confirms that the light pulses of the SpeedLaser
®
are hitting that
object by observing that the SpeedLaser
®
is reporting the range to
that object. The operator then moves the sighting system off of the
object and observes that the reported range changes, just as the
sighting system is no longer on the object and indeed should change.
5) Vertical Sight Alignment Test
Same as Horizontal alignment test but in the vertical axis