Chapter 3
Theory of Operation
Focus 30/35 Service Manual 3 - 12 P/N 79000035_SM, Version 1.5
Fig. 3-9 Principle schematic of Distance meter unit
Transmitter unit
The unit includes a Laser driver board with laser diode, the unit also includes the Tracker transmitter.
When the EDM is in DR mode the Tracker transmitter is closed by a shutter.
Fig. 3-10 Transmitter board
APD-Diode
Transmitter
board
Receiver board
Reference
mirrow
Reference
fiber
Receiver fiber
Transmitter prism
Tracker reflector
EDM mirror 2
Transmitter
diode
Filter
DR/Prism
Switch motor
with prism and
grey filter
Rhomboid prism
EDM mirror 1
0,4x0,3
mrad
Tracker shutter
Tracker transmitter board
incl. diode
Laser driver board
incl. diode
Reference fiber
Switch
DR/prism mode