2014 will see the replacement of the Canon EF 100-400 f/4.5-5.6L IS, and we should see some new new patents showing new optical formulas for its replacement. Below is a patent for an EF 70-400 f/4.5-5.6L IS.
Description and self-interpretation of the patent literature
- Patent Publication No. 2014-21256,2014-21257
- Publication date 2014.2.3
- Filing date 2012.7.18
- Example 2
- Zoom ratio 5.45
- Focal length f = 71.33-144.71-388.95mm
- Fno. 4.63-4.84-5.83
- Half angle ω = 16.87-8.50-3.18 °
- Image height Y = 21.64
- 240.00-284.68-303.83mm overall length of the lens
- BF 75.92-79.30-95.93mm
- 6-group zoom of positive and negative positive and negative positive and negative
- (Part of the fourth group) anti-vibration
- Rear Focus (Group 6)
Source: [EG]
cr
When you purchase through links on our site, we may earn an affiliate commission. Here's how it works. |