What is the difference of absolute optical encoders and incremental optical encoders in circuit?！

What is the difference of absolute optical encoders and incremental optical encoders in circuit? Does Incremental encoder can be turned into an absolute form by changing the display circuitry ?


Incremental encoders have a relative zero signal, which can be achieved with a simple position control.

Photoelectric incremental encoder and absolute encoder photoelectric encoder scale are essentially different. The incremental encoder is uniform scale lines, each line is the same, the absolute value of each of the code wheel position is different.
Incremental photoelectric encoder can not change the display circuit can become absolute; but now there are magnetic encoders on the market two or three outputs, and some are equipped with incremental and absolute value of

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