Patent: 50-300mm f/4.5-5.6 DO for EF-S & EF-M

That patent train continues for EF-M lens optical formulas, this time we see a 50-300mm f/4.5-5.6 DO lens for APS-C sized sensors. This optical formula patent shows the lens for both EF-M and EF-S mounts. It's definitely interesting to see diffractive optics development for consumer grade cameras.

Patent Publication No. 2016-57444 (Google Translated)

• Published 2016.4.21
• Filing date 2014.9.9

Example 1

• Zoom ratio 5.59
• Focal length 51.77 135.00 289.53
• F-number 4.65 5.05 5.85
• Half angle of view (degrees) 14.78 5.78 2.70
• Image height 13.66 13.66 13.66
• The total lens length 126.05 169.37 184.15
• BF 35.50 35.50 35.50

Example 2

• Zoom ratio 5.90
• Focal length 49.13 135.00 290.00
• F-number 4.65 4.95 5.85
• Half angle of view (degrees) 15.54 5.78 2.70
• Image height 13.66 13.66 13.66
• The total lens length 108.00 152.12 168.00
• BF 15.69 15.69 15.69

We have yet to see any full frame optical formulas for a full frame mirrorless camera body. We don't find this surprising as we expect any such camera be compatible with EF lenses.