Civil Engineering Reference
In-Depth Information
Fig. 5.11
Prism pole. The clear cylinder with the gold reflector contains a circular array of
LEDs which provide a light source for tracking. A
circular array
of small prisms can be seen a
few inches above. The
circular bullseye
level is at the
bottom
. The black knob allows the height
of the prism to be adjusted
Surveyors are aware that prism poles are subject to quite a lot of abuse in the
field and the bullseye levels are in constant need of adjustment. If the locations to
be made need to be accurate, it is always a good idea to check the prism pole to be
