Here is another in a long line of diffractive optics patents we’ve seen from Canon over the last couple of years. Since the Canon EXPO in 2015, we’ve all been wondering where the EF 600mm f/4 DO IS lens is, a lens we don’t think is ever coming at this point. A lot has changed over the last 3 years, and we expect any new DO super telephoto lens to be for Canon’s new RF mount.
This latest USPTO patent showcases both a 500mm and 600mm optical formula. As Canon News points out, this patent shows Canon moving the lens elements closer to the camera body to improve balance. This is the same sort of design we saw in the brand new EF 400mm f/2.8L IS III and EF 600mm f/4L IS III lenses.
Example 1:
Focal Length: 487.49mm
F-Number: 4.12
Half angle of view: 2.54º
Image height: 21.64mm
Total lens length: 409.74mm
Backfocus: 98.42mm...
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