Capacitive Sensing

Apples recent hits such as the iPhone, iPad, and iPod Touch devices along with the torrent of Android devices all usecapacitive sensing. With this technique the device creates a electromagnetic field and detects movement based on the disturbance of this field. Skin, for example, is a conductor and will transmit electricity. The changes in the field can be precisely detected. Materials that cannot conduct electricity are called insulators. In our runners case the glove is acting as an insulator between her finger and her iPhone. Since the electrical field is not altered by the insulating glove, the mobile phone does not detect her touches. Specialized gloves do exist that allow people to use capacitive sensing devices correctly. Typically, in the fingertips of these devices are conducting, instead of insulating, materials.