Capacitive Sensors for Thickness Measurement and Gauging

Two channel capacitive displacement measurement systems are widely used for high speed, non-contact thickness measurement of conductive materials such as disk media and various machined parts.

Thickness Measurement – Principle of Operation

Most thickness measurements based on capacitive sensing are made using the two probe “A+B”, or differential, method. The following is the basic concept:

The Formula for Thickness is:

• T=D-(A+B)

 

Where:

• D= Distance Between The Probes
• A= Distance From Probe A to Material To Be Measured
• B= Distance From Probe A to Material To Be Measured
• T= Thickness Of The Material To Be Measured