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Canon EF and RF Lenses – All Autofocus Motors
The introduction of automatically focusing lenses has changed photography in numerous ways. Autofocus systems have significantly improved the reliability and accuracy with which fast moving objects can be shot.
Once the unit is installed inside a lens barrel, a dedicated contact surface on the rotor pushes against wheels on an output ring (not shown in this illustration) that ultimately drives the focusing mechanism. In addition, this type of autofocus motor requires complex power supply and driving circuits including high frequency generation and feedback control system. These are L-lenses of the RF mount system that are specially designed to combine the benefits of photo and video technologies (such as a manual aperture ring normally found only on cine lenses).
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