Canon Patent Application: Canon 800mm 5.6

Canon appears to have filed a patent application on specifically a 800mm F5.6 lens.

The patent attempts to help reduce weight, size while maintaining a high degree of optical performance and low chromatic aberrations.  There are two embodiments, both are 800mm lenses.

For example;

Focal distance 780.00 
F number 5.80 
a half field angle (degree) -- 1.59 
Image height 21.64 whole length of the lens 485.85 
BF 128.77

Japan Patent Application 2018-087965