Rami Arieli: "The
Laser Adventure", Labs - Optics communication, page 3
Principle of Operation of the Laser
Receiver.
Any component that change
its electric properties when light fall on it can serve as a detector for
collecting the laser signals. Examples are: Solar cell, photodiode,
photo-transistor.
The output voltage of the detector is proportional to the
light intensity falling on its sensitive area.
The output of the detector is connected to a simple electronic
amplifier operating at audio frequencies (500-10,000 Hz are enough for
demonstration).
The circuit is shown in figure 2.
Figure 2: The Receiver.
It is recommended to connect the detector to the amplifier
with coax cable to avoid electronic noise from entering the amplifier.