Canon filed several new telephoto patents today: 200-400mm f/4, 600mm f/4, 300-600mm f/5.6 with a built in TC (280-560mm f/5.6、840mm f/5.6、420-840mm f/8).
- Patent Publication No. 2013-238827
- Publication date 2013.11.28
- Filing date 2012.5.17
- Example 1
- Zoom ratio 1.90
- Focal length f = 205.00 – 389.99mm
- Fno. 4.12
- Half angle ω = 6.02 – 3.18 °
- Image height Y = 21.64mm
- The overall length of the lens 389.84mm
- BF 68.49mm
- Teleconference insertion
- Focal length f = 287.00 – 545.98mm
- Fno. 5.77
- Half angle ω = 4.31 – 2.27 °
- Example 2
- Focal length f = 585.10mm
- Fno. 4.12
- Half angle ω = 2.12 °
- Image height Y = 21.64mm
- The overall length of the lens 467.32mm
- BF 83.15mm
- Teleconference insertion
- Focal length f = 819.00mm
- Fno. 5.77
- Half angle ω = 1.51 °
- Example 3
- Zoom ratio 1.90
- Focal length f = 307.50 – 585.00mm
- Fno. 5.88
- Half angle ω = 4.02 – 2.12 °
- Image height Y = 21.64mm
- The overall length of the lens 405.00mm
- BF 75.70mm
- Teleconference insertion
- Focal length f = 427.00 – 812.33mm
- Fno. 8.17
- Half angle ω = 2.90 – 1.53 °
- Canon patents
- Teleconverter BF is the same in insertion and after insertion before
- Vibration control
- Teleconference to be inserted into the appropriate location,teleconverter can be miniaturized
via: EG