Richard CanonNews / Friday, September 21, 2018 / Categories: Canon Patents This post may contain affiliate links(s). An affiliate link means I may earn advertising/referral fees if you make a purchase through my link, without any additional cost to you. It helps to keep this site afloat. Thank you in advance for your support. If you like what we do here, maybe buy me a coffee. Canon Patent Application: 600mm F4 DO Supertelephoto Canon has applied for another patent application dealing with diffractive optics. This patent application is for a 600 F4 Supertelephoto diffractive optics lens. This appear to be EF lens designs, and not RF, as the back focus is larger than 44mm. However, for super-telephotos, either mount could be used as the final lens design. Canon has shown off a prototype of the 600mm DO Supertelephoto for years now, sooner or later it's bound to show up. Focal length 585 F-Number 4.12 Half angle of view 2.12 Image height 26.4 BF 70.86 US Patent Application 20180259690 Richard CanonNewsRichard CanonNews Richard has been using Canon cameras since the 1990s, with his first being the now legendary EOS-3. Since then, Richard has continued to use Canon cameras and now focuses mostly on infrared photography. Richard is the founder and editor of CanonNews since 2017, and has worked as a writer on CanonRumors and other websites in the past. Other posts by Richard CanonNews Contact author Facebook page Print Please login or register to post comments.