Tag: DO

Patent: EF 400 f/4 DO IS II

Another DO patent We haven't seen a new DO lens in a…

Craig

April 14, 2013

Patent: 600 f/4 DO IS & 400 f/2.8 DO IS

Patent Time! More diffractive optic patents from Canon. This time, another 600…

Craig

May 22, 2012

Patent: New Diffractive Optic Patents

More DO Lenses? A few patents in regards to diffractive optics have…

Craig

April 20, 2012

Canon 16-35 f/2.8 DO Patent

More lens patents This is an interesting DO patent from Canon. There…

Craig

August 3, 2011