Laser Ally Speed LIDAR Operator Guide
Digital Ally, Inc.|Doc. 30157 Rev 12
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The rear panel will also display the indication “Approach” or
“Recede” to indicate that a vehicle has been targeted traveling in a
direction opposite to that of the Filter.
Differential Distance Test
Note: The Differential Distance Test is an optional accuracy check
preferred by some jurisdictions. It is not a manufacturer required test
for daily required testing; however it is an additional test that the
operator may complete if they wish.
Differential Distance: LIDAR in Metric Units (KPH)
The (KPH) Differential Distance Test uses two fixed targets separated
by a precisely known distance. Using the LIDAR’s range function to
determine the separation between the targets, the KPH Differential
Distance test provides a quick check of the LIDAR’s ability to measure
the distance between two targets.
Use two flat targets, approximately 0.5 metres x 0.5 metres square.
Place the targets at precise distances from the datum point (front of
the lens) where the LIDAR will be positioned. The targets should be
set at integer metre values from the LIDAR datum point and should
be approximately 10 metres apart. Please note, minimum range
capability is 3 metres. On the LIDAR unit, press the Menu button
, then use the up/down arrows until “Diff Distance” is
displayed. Press Enter
. Carefully obtain a range reading from
the first target and then press Enter
. Carefully obtain a range
reading from the second target and then press Enter
. The
LIDAR will then display the distance between the two targets on the
rear display. The distance should be within 0.5 metres of the actual
distance between the targets.
