What is a photoelectric encoder

Photoelectric encoder is by reading the patterns of the photoelectric coding plate or coding information to represent and photoelectric encoder is connected to the motor rotor position information. According to the working principle of the photoelectric encoder, photoelectric encoder can be categorized into absolute photoelectric encoder and the incremental photoelectric encoder, the following simple introduction and down the structure and working principle of absolute photoelectric encoder do is introduced.

The structure and working principle of absolute photoelectric encoder

Absolute photoelectric encoder as shown in figure, he is by reading the code disc on the binary coded information to indicate the absolute position information.

Code disc is made according to certain encoding disc. Figure 1 is a binary code disc, the blank part of the figure is pervious to light, by zeros. Blackening part is not pervious to light, with a '1'. Usually called ring of encoding code, each said a binary code, one of the most lateral is lowest, the most in the side is the highest level. If code disc has four yards, then from the inside to the outside of the code word respectively represented as binary 23, 22, 21 and 20, 4 bit binary can form 16 binary number, so will the disc divided 16 sectors, each sector has a 4 bit binary number, such as 0000, 0001,... , 1111.

Structure and working principle of the introduction of absolute photoelectric encoder

In accordance with the encoder on the formation of the code, configure corresponding photoelectric sensor, including light source, lens, encoder, photodiode, and drive circuit. When the encoder to certain Angle, the sector of pervious to light the corresponding photosensitive diode conduction, output low level '0', shading of the corresponding photosensitive diode is not conducting, a '1' output level, this form consistent with the encoding of high and low level of output, so as to obtain the position of the sector.