Canon Patent for 200-400mm Teleconverter Lens

Source: Egami (translated).

Canon filed a patent for a 200-400mm lens with built-in teleconverter and image stabilisation.

• 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 miniaturised