Capacitive position sensors measure displacement or proximity by detecting changes in capacitance between conductive elements. As a target moves, the electric field distribution shifts, producing a measurable change in capacitance that correlates with position. Key technology options include parallel-plate designs for short-range, high-precision measurements; interdigitated electrodes for surface or planar sensing; and differential capacitive systems that improve noise immunity and accuracy. Advanced implementations use shielding, guard rings, and signal conditioning electronics to minimize environmental interference such as humidity or electromagnetic noise.
These sensors are valued for their high resolution and accuracy, fast response, and ability to detect non-contact motion in conductive and non-conductive materials. Common applications include Aerospace & Power Generation (blade tip timing and blade tip clearance), Defence (Gun barrel profiling), Research and Industrial (high temperature & cryogenic position sensing). Their accuracy, versatility and reliability make them suitable for both micro-scale and large-scale measurement tasks.
