Applied Nanophotonics, Liquid Crystals and Biomedical Optics

Lateral effect position sensors are used in the time delay (TD) mode for temperature sensing and thermal expansion measurements. The TD mode operation avoids the need for signal normalisation, thus achieving better resolution and dynamic range over the voltage difference mode of operation. We demonstrate the measurement of the relative expansion of solids with accuracy better than 1% using heated copper rod. When the thermal expansion coefficient is known, the device can be used as a high-resolution, remotely operated, fast temperature sensor. Excellent agreement is obtained between measured and calculated quantities based on the dynamic equation that approximates the PSD as a distributed RC transmission line.