C6.3 - Compact Optical Sensor for the Measurement of Surface Microtopographies on Turbine Blades
- AMA Conferences 2015
2015-05-19 - 2015-05-21
- Proceedings SENSOR 2015
- C6 - Geometrial Measurements
- Y. Li, M. Kästner, E. Reithmeier - Gottfried Wilhelm Leibniz Universität Hannover (Germany)
- 453 - 457
The importance of measuring surface microtopographies for quality control has increased in the last decades. The inspection and measurement of complex shaped work pieces, like turbine blades or blisks (blade integrated disks), leads to a new challenge in measurement technology. In order to allow a precise measurement of surface microstructures, optical microscopes, such as confocal laser scanning microscopes and optical scanning microscopic interferometers, are usually used [1-3]. However, with common optical microscopes with 20x or 50x magnification objectives it is difficult to obtain a large spatial range which is necessary for measuring curved surfaces of turbine blades.
In this paper we present a compact non-contact measurement system based on a low coherence Michelson interferometer (LCI), which allows a nanometer-level vertical resolution and a millimeterlevel lateral range. The developed LCI-system using a telecentric lens allows a high accuracy surface microtopography measurement and a large FOV for measuring curved surfaces, which cannot be measured by common interferometric microscopes.