Canon Patent for EF-M 55-300mm f/4.5-6.3 DO IS Lens

Canon filed a new patent in Japan. The new patent describes a EF-M 55-300mm f/4.5-6.3 DO IS lens designed for EOS M mirrorless cameras with APS-C-sized image sensors.

Canon already has a telephoto lens for the EOS M system and it is the Canon EF-M 55-200mm F4.5-6.3 IS STM model. If the patent becomes live in production, it will be the telephoto zoom model in the EOS-M system with DO featuring diffractive optics.

Canon lenses which feature the diffractive optical (DO) are smaller and lighter compared to the same focal length lenses but the price becomes generally higher when the lenses have optical formual for DO.

The patent for the EF-M 55-300mm f/4.5-6.3 DO IS telephoto lens for APS-C mirrorless cameras can be seen below.

Canon EF-M 55-300mm f/4.5-6.3 DO IS Lens Patent


  • Patent Publication No. 2015-232674
    • Published 2015.12.24
    • Filing date 2014.6.11
  • Example 1
    • Zoom ratio 5.27
    • Focal length 55.04 135.00 290.01
    • F-number 4.60 5.18 6.30
    • Angle of view 13.94 5.78 2.70
    • Image height 13.66 13.66 13.66
    • Overall length of the lens 136.00 175.46 192.00
    • BF 35.50 35.50 35.50

via Egami