Chapter 3 ______________________________________________________ Functional Description 
VAISALA _______________________________________________________________________ 49 
 
  1104-090 
Figure 15  Optics Unit Receiver LTO212 
The following numbers refer to Figure 15 above: 
1 
=  Mounting chassis with an alignment mechanism, optics tube 
and optics suspension 
2  =  Window transmitter module 
3  =  Measurement CPU (including window receiver) 
4  =  Main receiver module 
Main Transmitter Module LTL112 
The main transmitter module LTL112 is mounted to the optics tube of 
the optics unit and is secured by a screw. It is connected to the 
measurement CPU using two connectors. The main transmitter module is 
shown in Figure 16 below. 
 
 1104-091 
Figure 16  Main Transmitter Module LTL112 
The main transmitter module contains a white, high-power LED as a 
light source and an optical diffuser foil for homogenous light distribution.