Patent: EF-M 18-40 Pancake
By| January 19, 2014
A patent showing an EF-M 18-40 f/3.5-5.6 pancake has come to light. With this patent a bunch of other optical formulas also appear, such as an 18-55 pancake, 10-20, and a 9-18. We currently have an EF-M 11-22, which is probably rooted from the latter two optical formulas.
A zoom pancake would be a nice addition to the geographically fragmented and oddly marketed EOS M line.
- Patent Publication No. 2014-6275
- Publication date 2014.1.16
- Filing date 2012.6.21
- Example 7
- Zoom ratio 3.00
- Focal length f = 18.10-37.01-54.30mm
- Fno. 4.20-6.20-8.20
- Half angle ω = 36.92-20.17-14.06 °
- Image height Y = 13.60mm
- 64.74-56.63-62.13mm lens length
- BF 0.50mm
- Canon patents
- The possible vibration damping by the second lens group
- Feeding whole, front focus, focusing, rear focusing, etc.