Here we have another patent for more cine lens optical formulas. This time for two lenses, a CN-E 20-100 T2.8 and a CN-E 20-120 T2.8-T3.5.
I'm starting to think we're going to see some new cinema lenses this fall once the EOS C300 Mark II begins shipping.
Patent Publication No. 2015-18083 (Google Translated)
- Published 2015.1.29
- Filing date 2013.7.10
Example 1
- Zoom ratio 6.00
- Focal length 21.00 87.93 125.94
- F number 2.77 2.77 3.66
- Half angle of 35.54 9.68 6.79
- Image height 15.00
- Overall length of the lens 314.76
- BF 50.03
- Example 2
Zoom ratio 5.00
- Focal length 20.00 69.46 100.00
- F number 2.76 2.77 2.77
- Half angle of 36.50 12.03 8.42
- Image height 14.80
- Overall length of the lens 294.44
- BF 50.07
Canon patents
- Positive and negative positive and negative positive five-group zoom
- Inner focus (part of the first group)
- Inner zoom