Canon Patent For 400mm, 600mm and 800mm Telephoto Lenses With Diffractive Optical Elements

Canon Patent

Hi Lows Note spotted a Canon patent application (2019-028317) for 400mm f/4, 600 mm f/4, and 800 mm f/5.6 telephoto lenses with DOE (Diffractive Optical Elements).

Focal distance 582.00 
F number 4.12 
Half field angle (degree) 2.13 
Image height 21.64 
Whole length of the lens 394.25 
BF 62.79 

Focal distance 405.00 
F number 4.12 
Half field angle (degree) 3.06 
Image height 21.64 
Whole length of the lens 330.16 
BF 50.46 

Focal distance 795.00 
F number 5.60 
Half field angle (degree) 1.56 
Image height 21.64 
Whole length of the lens 490.24 
BF 105.13 

More Canon patent applications are listed here. Some particularly interesting patent applications we think might get into production in the next few years are these: