Low cost optical fibre measuring instrument

The main objective of this project is to develop a low-cost solid-state instrument to use with optical fibre physical or chemical sensor (e.g. temperature, colour, pressure, pH etc.). This portable instrument employs opto-electronic devices such as light emitting diode (LED) as a light source and semiconductor photodiode (PD) as a photodetector. A Fibre optic cable is used as a media or transmission line to link between light sources, sensor and photodetector. The project instrument has an internal reference to conect the changes in the signal intensity due to fibre bending or fibre connection and environmental effects. The resolutions of this project is 0.1 mm. For this project, an optical fibre displacement sensor was fabricated since the basic concept of displacement sensor can be applied for many type of sensors. This same sensor can also be used to measure colours.