9
Principal of measurement
The bar code of the staff is stored in the instrument
as a reference signal. When measuring, the visible
section of the staff within the field of view is captu-
red by the line decoder as a measuring signal. Then
the measuring signal is compared to the reference
signal. This results in the height reading and hori-
zontal distance. The staff must be perpendicular
during measurement, as for optical levelling. With
artificial lighting of the staff, mesurements can be
made in the dark (The sensitivity of the sensor ran-
ges from the highest frequiencies of visible light
down to the frequency of infra red light).
Validity
This manual is valid for both instruments of the DNA
series. Sections only valid for the DNA03 are mar-
ked accordingly.