Another patent
This is probably the third separate patent I have seen for an EF 100-400 f/4.5-5.6L IS over the last 24 months. A zoom ring version does exist in the wild. We're told the push/pull is finished and we'll get a properly sealed 100-400. The cost will be north of $2500 USD and we could finally see it announced before the end of the year. Also appearing in the patent is a 70-300.

The breakdown below is Google translated

  • 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

Source: [EG]


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