Autofocus systems have revolutionized photography by enabling the quick and accurate capture of fast-moving subjects, making it more accessible to the masses. Canon has been at the forefront of lens technology since 1981, introducing seven different autofocus motor technologies. The focus is synonymous with sharpness in optics, and Canon has continuously developed autofocus systems, with EF lenses standardizing autofocus features. The Arc-Form Drive was the first autofocus motor used in EF lenses, later replaced by the ring-type ultrasonic motor (USM) technology. Canon’s USM drives are exceptional, using piezoelectric effects and friction for silent, fast, and powerful focus, unlike traditional motors based on magnetism.
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