Canon EF 100-400mm f/4.5-5.6 and EF 70-300mm f/4.5-5.6 Lens Patents

Egami has discovered new patents filed by Canon. The new Canon patents is for zoom lenses. One of them is Canon EF 100-400mm f/4.5-5.6 and the other one is named as Canon EF 70-300mm f/4.5-5.6.

There are several EF 100-400mm f/4.5-5.6 patents filed by Canon back in time. This may mean we come close to an announcement of the new EF 100-400mm f/4.5-5.6 lens.

Below are the details of the two new Canon zoom lenses translated by Google.

Canon EF 100-400mm f/4.5-5.6 and EF 70-300mm f/4.5-5.6 Lens Patents

Patent Publication No. 2013-105053

• • Publication date 2013.5.30
  • Filing date 2011.11.15
• Example 1
  • Zoom ratio 4.01
  • Focal length f = 72.48-135.49-290.86mm
  • Fno. 4.58-4.94-5.85
  • Half angle ω = 16.62-9.07-4.25 °
  • Image height Y = 21.64mm
  • 143.42-175.48-201.87mm overall length of the lens
  • BF 39.98mm
• Example 3
  • Zoom ratio 3.75
  • Focal length f = 104.16-166.66-391.00mm
  • Fno. 4.60-5.20-5.80
  • Half angle ω = 11.73-7.40-3.17 °
  • Image height Y = 21.64mm
  • 221.48-252.31-300.68mm overall length of the lens
  • BF 70.65-87.69-113.37mm
• Canon patent
  • I want to put in the first group the anomalous dispersion optical element
  • It is possible correction and lateral chromatic axial chromatic aberration, but spherical aberration of color and field curvature occurs
  • By optimizing the placement, the correction and field curvature, the spherical aberration of the color of g-line

via: Egami