Canon Patents For EF 55mm f/1.4 and Other Prime Lenses

Egami spotted a new patent filed by Canon in Japan. The new patent describes various “normal” fast prime optical formulas.

Along with the Canon EF 55mm f/1.4 lens, another EF 35mm f/1.4 and other fast primes also mentioned in the patent.

See the various optical formula images below. Patent details translated via Google Machine.

Canon Patents For EF 55mm f/1.4 Prime Lens

canon-ef-55mm-f1-4-prime-lens-patents

Patent Description (Google Translated)

  • Patent Publication No. 2014-123018
  • Publication date 2014.7.3
  • Filing date 2012.12.21
  • Image height = 21.64mm
  • Inner focus
Example Focal length Fno. Half angle The overall length of the lens BF MOD
One 49.53 1.45 23.60 99.46 38.10 450
Two 35.88 1.45 31.09 126.92 38.77 300
Three 55.42 1.45 21.33 100.44 40.24 450
Four 50.75 1.45 23.09 98.17 38.29 450

via EG