How do incremental encoders output digital signal?！

Incremental rotary incremental rotary optical encoder has a digital form of electrical output proportional to the input angular position of the shaft of the electromechanical device.

Angular displacement incremental rotary optical encoder enabled directly converted to digital form.
Incremental rotary optical encoder is an angular position sensor:
It has a mechanically coupled to the rotating disk which is rigidly fixed to the input drive shaft. Continuous mark opaque and clear segments on the disc surface.

From the infrared light emitting diode light reaches the receiver via infrared transparent slits of the rotating disk. The analog signal is created.

Then electronically, the signal is amplified and converted to digital form. Then, the signal is transmitted to the data processor.

Roundss equivalent models:

TRD-J10-S
TRD-J10-SC
TRD-J10-SCW
TRD-J10-SS
TRD-J10-SW
TRD-J10-SWS
TRD-J120-RZ
TRD-J120-RZC
TRD-J120-RZCL
TRD-J120-RZCW
TRD-J120-RZCWL
TRD-J120-RZL
TRD-J120-RZS
TRD-J120-RZSL
TRD-J120-RZV
TRD-J120-RZVC
TRD-J120-RZVCW
TRD-J120-RZVS
TRD-J120-RZVW
TRD-J120-RZVWS
TRD-J120-S
TRD-J120-SS
TRD-J120-SW
TRD-J120-SWS
TRD-J200-RZ
TRD-J200-RZC
TRD-J200-RZCL
TRD-J200-RZCW

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