A new EF 70-200mm f/4L IS lens patent shows up on egami. The old EF 70-200mm f/4L IS USM lens was released in 2006, and the price is about $1,000.
Description (Translated by Google)
- Patent Publication No. 2013-105131
- Publication date 2013.5.30
- Filing date 2011.11.16
- Example 1
- Zoom ratio 2.68
- Focal length f = 72.11-131.37-193.4mm
- Fno. 4
- Half angle ω = 16.7-9.35-6.38 °
- Image height 21.64mm
- The overall length of the lens 234.52mm
- BF 50.12mm
- Example 2
- Zoom ratio 2.68
- Focal length f = 72.14-130.58-193.38mm
- Fno. 4
- Half angle ω = 16.69-9.41-6.38 °
- Image height 21.64mm
- The overall length of the lens 213.85mm
- BF 39.96mm
- Example 3
- Zoom ratio 2.68
- Focal length f = 72.11-132.09-193.4mm
- Fno. 4
- Half angle ω = 16.7-9.3-6.38 °
- Image height 21.64mm
- The overall length of the lens 233.51mm
- BF 49.05mm
- Existing techniques
- If you have a single focus group is easy aberration There is a change in the RF and IF
- Canon patent
- Inner zoom
- Inner focus
- Floating
- MOD 300mm
- β (Tele) = -0.5
Performance
via: egami