Oryx 5890 Capacitive Plastic Thickness Measurement Gauge

The Oryx 5890 is a Capacitive Sensor plastic thickness measurement device used to measure the thickness of non-conductive films. It is suitable for measurement of plastic films from 10 microns to 3 millimeters thick.

Advantages

Compared to other noncontact sensing technologies such as optical, laser, eddy-current, and inductive, high-performance capacitive sensors have some distinct advantages:

  • Higher resolutions including sub nanometer resolutions.
  • Not sensitive to material changes: Capacitive sensors respond equally to all conductors.
  • Less expensive and much smaller than laser interferometers.

Applications

Thickness Measurement: Measuring material thickness in a non-contact fashion is a common application for capacitive sensors. The most useful application is a two-channel differential system in which a separate sensor is used for each side of the piece being measured.

Capacitive sensor technology is used for thickness measurement in these applications:

  • Silicon wafer thickness
  • Plastic Films

Nonconductive Thickness: Capacitive sensors are sensitive to nonconductive materials which are placed between the probe's sensing area and a grounded back target. If the gap between the sensor and the back target is stable, changes in the sensor output are indicative of changes in thickness, density, or composition of the material in the gap.

Capacitive Sensors Overview

Capacitive sensors (capacitive linear displacement sensors) are noncontact devices capable of high-resolution position measurement and/or displacement measurement of any conductive target. They can also be used to measure the thickness of nonconductive targets. The nanometer resolution of high-performance capacitive sensors makes them indispensable.

Capacitive sensors use the electrical property of "capacitance" to make measurements. Capacitance is a property that exists between any two conductive surfaces within some reasonable proximity.

It is this change of capacitance that capacitive sensors use to indicate changes in position of a target or of the quantity of material in the gap. High-performance displacement sensors use small sensing surfaces and as result are positioned close to the targets (0.25-2 mm).

Capacitive displacement sensors for use in precision displacement measurement and metrology applications use complex electronic designs to execute complex mathematical algorithms. Unlike inexpensive sensors, these high-performance sensors have outputs which are very linear, stable with temperature, and able to resolve incredibly small changes in capacitance resulting in high resolution measurements of less than one nanometer.