The light reflected from a mirror on a probe, which is positioned on both sample and reference rods, is rotated by uneven thermal expansions of the two materials. A simple method is described to measure this rotation and hence the thermal expansion using a variable area slit and photodetector combination. The method is capable of determining very low thermal expansions of ceramic materials with high precision and accuracy. A measurement sensitivity of 10-6 for ΔL/L can easily be obtained.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering