Incremental encoderIt is to convert displacement into periodic electrical signals, and then convert this electrical signal into counting pulses, using the number of pulses to represent the magnitude of displacement.An encoder is a device that converts angular or linear displacement into electrical signals.The former becomes a code wheel, while the latter is called a code ruler. According to the reading method, encoders can be divided into two types: contact type and non-contact type. Contact type uses electric brush output, where one electric brush contacts the conductive or insulating area to indicate whether the code state is "1" or "0"; The non-contact receiving sensitive element is a photosensitive element or a magnetic sensitive element. When using a photosensitive element, the state of the code is represented by a transparent area and a non transparent area to indicate whether it is "1" or "0".According to the working principle, encoders can be divided into two categories: incremental and linear.Incremental encoderIt is to convert displacement into periodic electrical signals, and then convert this electrical signal into counting pulses, using the number of pulses to represent the magnitude of displacement. Each position of the encoder corresponds to a specific digital code, so its indication is only related to the starting and ending positions of the measurement, and not to the intermediate process of the measurement.rotateIncremental encoderOutput pulses during rotation, and determine its position through a counting device. When the encoder is stationary or powered off, rely on the internal memory of the counting device to remember its position. In this way, when there is a power outage, the encoder cannot move in any way. When there is a power outage, there should be no interference or loss of pulses during the encoder output process. Otherwise, the zero point remembered by the counting device will shift, and the amount of this shift is unknown, only after the occurrence of erroneous production results can it be known.The solution is to increase the reference point, and the encoder will correct the reference position into the memory position of the counting device every time it passes through the reference point. Before the reference point, the accuracy of the position cannot be guaranteed. For this reason, in industrial control, there are methods such as finding a reference point before each operation and finding the change when starting up.For example, the positioning of a printer scanner is based on the principle that every time it is turned on, we can hear a crackling sound as it searches for the reference zero point before it starts working.　　Features:　　When the shaft rotates, there is a corresponding pulse output, and the counting starting point can be set arbitrarily, which can achieve infinite accumulation and measurement of multiple turns. One revolution of the encoder shaft will output a fixed number of pulses, which are determined by the number of lines in the encoder grating. When it is necessary to improve the resolution, the A and B signals with a 90 degree phase difference can be used for frequency doubling or to replace the high-resolution encoder.