Capacitive Sensors in Printed Photopolymer Structures: Dielectric State, Electrode Geometry, Humidity and Calibration

Capacitive sensors made with printed photopolymer structures convert geometry and dielectric state into an electrical signal. Their apparent sensitivity is therefore inseparable from electrode dimensions, dielectric thickness and architecture, polymer permittivity, moisture uptake, temperature, viscoelastic deformation and the readout frequency. This review defines a qualification framework for capacitive sensors in which capacitance is treated as a state-dependent measurand rather than a fixed material property. It distinguishes geometry-driven and permittivity-driven response, explains why humidity and temperature can shift both baseline and sensitivity, and requires calibration across the declared environmental and mechanical envelope. A non-compensatory matrix links dimensional verification, dielectric characterization, electrode stability, environmental cross-sensitivity, hysteresis, drift and cyclic repeatability. The central conclusion is that calibration is valid only for the specific printed architecture and conditioned dielectric state from which it was derived.

ER-262 · Version 0.2.