[Patent] Canon Files Patent For 14mm f/2.8 Lens (better coating, low refractive index)

Egami (translated) spotted another patent filed by Canon. This time it is for a 14mm f/2.8 lens with improved coating (tubular coating):

It seems it is possible to realize a low-refractive-index low reflectivity by the structure below the diffraction limit, even without the uneven surface of the coating. 14mm F2.8 is what I want you to adopt all means patent coating of the lens as the front lens is large, yet is protruding.

• Patent Publication No. 2012-159723
  • 2012.8.23 Release Date
  • 2011.2.1 filing date
• Example 1
  • F = 14.3mm focal length
  • Fno. = 2.89
  • Half angle ω = 56.6 °
  • 14 images in 10 groups lens configuration
• Existing coating roughness
  • In daily use, dirt or dust may adhere, could not wipe, sex or bad Mentenasu productivity and manufacturing process
• Canon patent
  • (Coating applied to one surface of a lens) thin film layer
  • Having a plurality of tubular spaces are arranged parallel to the tube
  • Maximum opening diameter of the tubular space below 400nm
  • The inorganic oxide materials (silica, titania)

[via Egami]