skip to Main Content

Canon Patent for EF-EF-M Adapter with Improved Auto-Focus Speed

2015_34903_fig01

Egami (translated) spotted what could be Canon’s best move to push their mirrorless cameras. A new EF-EF-M adapter that should deliver better AF speed when using EF and EF-S lenses. While the AF performance of Canon’s new EOS M3 is excellent with the native EF-M lenses, AF performance is limited when using EF lenses via the currently available adapter. If Canon puts such an adapter on the market it would a huge selling point for the EOS M3. Access to Canon’s extended lens lune-up, and same AF performance as with native lenses!

Machine translated patent description:

  • Patent Publication No. 2015-34903
    • Published 2015.2.19
    • Filing date 2013.8.9
  • Master lens
    • Zoom ratio 2.69
    • Focal length 72.13 135.02 193.99mm
    • Fno. 2.90
    • Half angle ω = 10.72 5.78 4.03 °
    • Image height Y = 13.66mm
    • Overall length of the lens 237.36mm
    • BF 54.00mm
  • Adapter installed
    • Zoom ratio 2.69
    • The focal length f = 72.12 135.00 193.96mm
    • Fno. 2.90
    • Half angle ω = 10.72 5.78 4.03 °
    • Image height Y = 13.66mm
    • Overall length of the lens 239.70mm
    • BF 16.77mm
  • Canon patent
    • Fast AF adapter
    • Wobbling corresponding
    • 3-group configuration of positive and negative positive
    • 2 group also serves as a focus group and the anti-vibration group
    • And realize high-speed AF focus group was lighter
Back To Top

Notice

This website or its third-party tools use cookies, which are necessary to its functioning and required to achieve the purposes illustrated in the cookie policy. If you want to know more or withdraw your consent to all or some of the cookies, please refer to the cookie policy.
By closing this banner, scrolling this page, clicking a link or continuing to browse otherwise, you agree to the use of cookies.