Canon Patent for 12-32mm T3.5 and a 15-47mm T2.8 Cinema Lenses

Egami (translated) spotted a patent for two Cinema lenses, a 12-32mm T3.5 and a 15-47mm T2.8 lens.

• Patent Publication No. 2015-34858
  • Published 2015.2.19
  • Filing date 2013.8.8
• Example 1
  • Zoom ratio 2.50
  • The focal length f = 12.50 18.75 31.25mm
  • Fno. 3.50
  • Half angle ω = 51.21 39.67 26.45 °
  • Image height Y = 15.5mm
  • Overall length of the lens 193.59
  • BF 42.84
• Example 2
  • Zoom ratio 2.81
  • Focal length 16.00 26.88 45.00
  • Fno. 2.80
  • Half angle of 44.18 30.05 19.06
  • Image height Y = 15.5mm
  • Overall length of the lens 247.38
  • BF 43.27
• Canon patent
  • Negative positive and negative positive 4-group zoom
  • Inner zoom (the second group)
  • Inner focus (rear group of the first group)