Beam Divergence - Spectra Geospatial Focus 35 User Manual

6 Instrument Technology

Beam Divergence

All distance meter measurement beams diverge as the range from the instrument increases. The
divergence of the distance meter beam relates to an increase in the size of the area being sampled, not
to a degradation of the measurement precision.
A larger measuring area at longer range is generally better because it enables smaller objects, such as
power lines and antennas, to be detected and accurately measured. With a smaller measuring area,
these small objects can be easily missed. A smaller measuring area has advantages when measuring
tight corners and vertices at close range. When observing measurements to a tight corner, the distance
meter beam divergence introduces a range error caused by the size of the sampling area.
Measuring to an inner and outer corner:
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