Glasfaser Optik

Experiment P5.8.7.3 introduces to glass fibre optics. Within this experiment the diode laser itself will be characterised with respect to its output power as function of its temperature and injection current. The spatial intensity distribution is measured by means of the provided rotation stage.
Cutting and preparing the fibre is part of the practical training. The light of the diode laser is coupled into the fibre by means of adjustable microscope objectives. The coupling efficiency is monitored with the photodetector detecting the light coming out at the end of the fibre.
The intensity distribution of the light emerging at the end of the fibre is measured and the numerical aperture determined.
By modulating the diode laser by means of the provided microprocessor controlled device the time of flight inside the fibre will be measured. From the results either the length of the fibre or the speed of light is calculated.