Canon Patent: 10-20mm f/4, 10-20mm f/2.8-4 And 9-18mm f/4 Lenses

Canon Patent

A new Canon patent application. Canon patent 2024023099 (Japan, published 2/21/2024) discusses optical formulas for three wide angle zoom lenses.

  • 10-20mm f/4
  • 10-20mm f/2.8-4
  • 9-18mm f/4

From the patent literature:

  • An object of the present invention is to provide a zoom lens that is small and has good optical characteristics, and an imaging device and an imaging system including the zoom lens.
  • BACKGROUND ART: Zoom lenses used in imaging devices are required to have a wide angle of view, be compact, and have good optical characteristics. As a wide-angle zoom lens, a so-called negative lead type zoom lens in which a lens group with a negative refractive power is arranged closest to the object side is known.
  • A negative lead type zoom lens has the characteristics that it is relatively easy to widen the angle of view and easily obtain a long back focus. However, negative lead type zoom lenses tend to have an asymmetrical lens configuration with respect to the aperture stop. Therefore, it is difficult to correct various aberrations, for example, it is difficult to suppress aberration fluctuations during focusing, and it is very difficult to obtain high optical performance.
  • In particular, in the inner focus type, in which focusing is performed using a small and lightweight lens group located closer to the image side than the first lens group in order to perform high-speed focusing, aberration fluctuations during focusing tend to increase.
  • The present invention provides a zoom lens that is compact and has good optical characteristics, and an imaging device and an imaging system having the zoom lens.

Example 1

  • Focal length: 10.33-19.39
  • F value: 4.08-4.12
  • Half angle of view: 61.36-48.13
  • Image height: 18.92-21.64
  • Total length: 128.82-123.27
  • Back focus: 12.13

Example 2

  • Focal length: 9.20-17.90
  • F value: 4.08-4.12
  • Half angle of view: 64.04-50.40
  • Image height: 18.90-21.64
  • Total length: 125.26-119.35
  • Back focus: 10.50

Example 3

  • Focal length: 11.30-23.90
  • F value: 4.08-4.12
  • Half angle of view: 59.29-42.15
  • Image height: 19.02-21.64
  • Total length: 129.79-129.33
  • Back focus: 14.54-10.54

Example 4

  • Focal length: 10.30-19.80
  • F value: 2.89-4.12
  • Half angle of view: 61.76-47.54
  • Image height: 19.18-21.64
  • Total length: 132.94-127.01
  • Back focus: 11.35

More Canon patents are listed here.

[via asobinet]

Canon Patent: RF 9-18mm f/4 Wide Angle Zoom For EOS R System

Canon Patent

Here is a new Canon patent application, and it is a rather interesting one.

Canon patent application P2022065383 (Japan) discusses optical formulas for a RF 9-18mm f/4 wide angle zoom lens for the Canon EOS R system.

PROBLEM TO BE SOLVED: To provide a zoom lens which is compact and has high resolving power while having a wide angle of view.

With the increase in the number of pixels of an image pickup apparatus, there is a demand for a zoom lens having a wide angle and high optical performance. Patent Document 1 discloses a wide-angle zoom lens having a focal length at a wide-angle end of about 11 mm in terms of 35 mm and an angle of view of about 120 °.

However, when the zoom lens is widened, the refractive power of each lens constituting the zoom lens increases and the resolution decreases.

The present invention provides a zoom lens having a wide angle of view, yet being compact and having high resolving power.

Example 1

  • Focal length: 9.27-17.46
  • F value: 4.12
  • Half angle of view: 66.80-51.10
  • Image height: 21.64
  • Overall length: 130.07-127.77
  • Back focus: 11.00

The Canon patent was spotted by Asobinet. More Canon patent applications are listed here. Some particularly interesting patent applications we think might get into production are these:

Canon patent for EF-M 9-18mm f/3.5-4.5 STM lens

canon patent

Something is moving in Canon’s EOS M department. Here we have another Canon patent for an EF-M lens,, a EF-M 9-18mm f/3.5-4.5 STM.

We already have an ultra wide-angle lens for the EOS M system, the EF-M 11-22mm f/4-5.6 IS STM. Will the optic formula described in the Canon patent ever hit the market? Hard to say.

  • Patent Publication No. 2016-54371
    • Published 2016.4.14
    • Filing date 2014.9.3
  • Example
    • Zoom ratio 1.90
    • Wide-angle intermediate telephoto
    • Focal length 9.22 14.05 17.50
    • F-number 3.39 4.04 4.63
    • Half angle of view (degrees) 53.07 44.12 37.91
    • Image height 12.27 13.63 13.63
    • Overall length of the lens 89.68 83.60 86.84
    • BF 14.22 15.78 16.00
  • Canon patent
    • Upon correction of the distortion, providing a constraint on stretching amount at each image height
    • Properly set the curve shape of the distortion aberration

[via Egami]

Canon Patent for EF-S 9-18mm f/4.5-5.6 Lens


Egami (translated) spotted a patent filed by Canon for a 9-18mm f/4.5-5.6 IS STM lens for APS-C cameras. The lens design looks similar to the recently announced EF-S 10-18mm f/4.5-5.6 IS STM.

  • Patent Publication No. 2014-225002
    • Published 2014.12.4
    • Filing date 2013.4.25
  • Canon patent
    • 4-group configuration of negative positive and negative positive
    • Inner focus
    • And a plastic aspherical first lens group
    • [0013] According to the present invention, the change in imaging magnification upon focusing on less, high speed focusing is obtained zoom lens easy wide angle.