An inexpensive light source and detector module for fibre-optic measurements

This paper deals with the question of whether an inexpensive optical sensor head, a so-called CD pick-up, from a compact disc player system can be used for simultaneously directing light into and detecting light received from an optical fibre. The investigation shows that the CD pick-up is well suited for intensity-based fibre-optic sensors. The benefit of using a CD sensor head is that it is a small-sized module including a diode laser, driver, detector, signal conditioning and lens system. Furthermore, the study shows that the CD pick-up may be used for fibre-optic interferometry as well.