USER'S GUIDE ____________________________________________________________________
106 __________________________________________________________________ M211187EN-C
0009-006
Figure 38
FSR102 Receiver Block Diagram
An ambient light level as high as 30 kcd/m
2
neither influences the
detection of the photodiode, nor saturates the preamplifier. The DC level
is monitored for detecting eventual saturation caused by the ambient
light.
Two infrared LEDs are provided for the backscatter and contamination
measurement. The light level is sampled and converted using the same
method of detection described with the scattering signal measurement.
The window contamination measurement principle is based on the
change of the total reflection of the light beam on the window surface.
The principle is shown in Figure 37 on page 105.
