The incremental encoder converts the displacement into a periodic electrical signal, then converts the electrical signal into a count pulse. The number of pulse represents the displacement size.
An encoder is a device for converting angular displacement or linear displacement into electrical signals. The former is called code disk, the latter is called yardstick. According to the readout method, encoder can be divided into two kinds contact type and non-contact. Contact output uses brush output. Brush contacts conductive area or insulation area representing the state of the code is "1" or "0". The non-contact sensitive element is photosensitive element or magnetic sensor, using the light sensitive element as the photic zone and light-proof representing the state of the code is "1" or "0".