From the touchscreen on your smartphone to advanced industrial automation systems, capacitive sensors are quietly revolutionizing the way humans interact with machines. These sensors detect touch, position, humidity, fluid levels, and more—without requiring physical contact—making them one of the most versatile technologies in the sensing world.

What is a Capacitive Sensor?
A capacitive sensor detects changes in capacitance caused by the presence or movement of an object, usually a conductive material like the human body. It operates based on the principle of capacitive coupling, where two conductive surfaces separated by a dielectric form a capacitor. When a finger or object comes near the sensor, the capacitance changes, triggering a response.

How It Works:
The sensor forms an electrostatic field.

When a conductive object (like a human finger) enters the field, it disturbs the capacitance.

This change is detected and converted into a signal (such as a touch or proximity command).

Types of Capacitive Sensors
Self-Capacitance: Measures changes in capacitance at a single electrode.

Mutual Capacitance: Measures changes between two electrodes—used in multi-touch systems.

Projected Capacitive (PCAP): Used in modern touchscreens for better accuracy and multi-touch support.