Canon News has uncovered another diffractive optic patent for supertelephoto optical formulas has shown up at the USPTO.
This patent covers the following:
- EF 200mm f/2
- EF 400mm f/2.8
- EF 800mm f/5.6
Canon continues to work away at more and more diffractive optics development, but we're still waiting to see new products come to market. The last DO lens released by Canon was back in 2014 when they announced the EF 400mm f/4 DO IS II.