Linear encoder

Linear encoders are transducers that exploit many different physical properties in order to encode position. Linear encoder technologies include optical, magnetic, inductive, capacitive and eddy current. Optical technologies include shadow, self imaging and interferometric. The encoder can be either incremental or absolute. In an incremental system, position is determined by motion over time; in contrast, in an absolute system, motion is determined. by position over time. The sensor reads the scale to convert the encoded position into an analog or digital signal, which can then be decoded into position by a digital readout (DRO) or motion controller. An early industry standard was 12V peak-peak current signals, but more recently this has been replaced with 1V peak to peak current signals. Compared to digital transmission, the lower bandwidth helps to minimise emissions' lower bandwidth. The industry standard for linear encoder signals is quadrine s/rine signals. These are transmitted differentially so as to improve noise immunity. These signals can be monitored easily using an XYoscope to display in a circular mode.