Canon Patent: 24-300mm F4-5.6, 24-400mm F4-5.6 And 20-240mm F4-6.3 Lenses

Eos R With Aps-c

Here is a new Canon patent application for what appears to be a bunch of slow zoom lenses. Kit lenses?

Canon patent application 2024005834 (Japan, published 01/17/2024) discusses optical formulas for three zoom lenses:

  • 24-300mm F4-5.6
  • 24-400mm F4-5.6
  • 20-240mm F4-6.3

From the patent literature:

  • [Problem] To obtain a high-performance zoom lens with a high zoom ratio while the entire system is compact.
  • [Background Art] In recent years, as an imaging optical system used in an imaging device, a small zoom lens with a high zoom ratio (high zoom ratio), high optical performance over the entire zoom range, and a short overall lens length has been used. That is what is required.
  • However, in the zoom lens disclosed in Patent Document 1, the Abbe number of the positive lens included in the first lens group is small, and when the zoom ratio is increased, the longitudinal chromatic aberration becomes large, especially at the telephoto end.
  • Accordingly, an object of the present invention is to provide a zoom lens having a high zoom ratio and high optical performance, while the entire system is small.

Example 1

  • Focal length: 24.72-291
  • F value: 4.12-5.77
  • Half angle of view: 37.35-4.25
  • Image height: 21.64
  • Total length: 175-258.9
  • Back focus: 13.81-68.61

Example 2

  • Focal length: 24.72-390
  • F value: 4.12-5.77
  • Half angle of view: 37.35-3.18
  • Image height: 21.64
  • Total length: 180-300.09
  • Back focus: 14.63-81.63

Example 3

  • Focal length: 20.6-240
  • F value: 4.12-6.3
  • Half angle of view: 42.48-5.15
  • Image height: 21.64
  • Total length: 174.99-284.99
  • Back focus: 14.63-81.63

[via asobinet]

Canon patent for EF 24-300mm f/3.5-5.6 lens for full-frame DSLR

24-300mm f/3.5-5.6

Canon patent for a EF 24-300mm f/3.5-5.6 USM lens for full-frame sensors. The patent description doesn’t mention image stabilisation (IS), so it’s unlikely this will be the replacement for the Canon EF 28-300mm f/3.5-5.6L IS (announced 2001).

As usual, a filed patent doesn’t mean the described gear will necessarily hit the market. On the other hand, this may just be a patent on the way to the replacement for the 28-300mm f/3.5-5.6, and we could soon see another patent for a similar optical formula and with added IS.

  • Patent Publication No. 2015-215438
    • Published 2015.12.3
    • Filing date 2014.5.9
  • Example
    • Focal length 24.70 101.33 292.01
    • Fno 3.50 4.59 5.87
    • ω (degrees) 41.22 12.05 4.24
    • Image height 21.64 21.64 21.64
    • Overall length of the lens 202.71 232.50 288.71
    • BF 38.78 43.69 75.66


[via Egami]