Patent: Canon RF 70-200mm f/4

[Loswr]

For a little light reading while having my morning cup of coffee, I read the patent.

You’re a brave man. I need to wait an hour or so for the caffeine to kick in before reading a patent.

 

[Richard-CN]

For a little light reading while having my morning cup of coffee, I read the patent. Not only does the 58/1.4 patent show two moving focusing elements, but also the 70-200/4 shows it and mentions having two sets of moving elements for focusing.

Yes. Unlike most lens patents, this one was really about the focus system and not the lenses.

 

[Jethro]

from what I can tell the 3 RF lenses that I found yesterday all have the potential of containing IS.

Fantastic if that's the case - I take it the IS elements can be added later and don't need to be patented along with the rest of the formula?

 

[Richard-CN]

Fantastic if that's the case - I take it the IS elements can be added later and don't need to be patented along with the rest of the formula?

the 28mm 1.8 and the 50mm 1.8 definitely mention the IS element.
this patent was really about the dual auto focus motors and related logic surrounding that, it didn't go into much detail of the lens design.