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October 29, 2014
Posted in patents

Canon Patent for 35mm f/1.4 Lens



Egami (translated) spotted a Canon patent for a 35mm f/1.4 lens.

  • Patent Publication No. 2014-202952
    • Published 2014.10.27
    • Filing date 2013.4.5
  • Example 1
    • Focal length f = 34.20mm
    • Fno. 1.45
    • Half angle ω = 32.32 °
    • Image height Y = 21.64mm
    • Lens length 129.16mm
    • BF 39.35mm


October 28, 2014
Posted in patents

Canon Patent For 55-250mm f/4-5.6 IS STM Lens For EOS M System


Egami (translated) spotted a patent for a 55-250mm f/4-5.6 IS STM lens with EF-M mount. Curious because there is already an EF-M 55-200mm f/4.5-6.3 IS STM lens for the EOS M system.

  • Patent Publication No. 2014-199421
    • Published 2014.10.23
    • Filing date 2013.3.13
  • Example
    • Zoom ratio 4.36
    • Focal length 56.14-134.30-245.00mm
    • Fno. 4.50-5.09-6.45
    • Half angle ω = 13.67-5.81-3.19 °
    • Image height Y = 13.66mm
    • Overall length of the lens 119.39-157.52-184.41mm
    • BF 22.04-27.75-50.36mm
    • Positive and negative positive and negative negative 5-group zoom
    • Inner focus (group 4)
October 20, 2014
Posted in patents

Canon Patent For 10-22mm Lens With Liquid Element (it’s not the first)

Lens With Liquid Element

Egami (translated) spotted a patent filed by Canon for 10-22mm f/3.5-4.5 lens with a liquid element. Liquid lenses work by applying an electric voltage to an electrolytic solution (that’s the liquid) in order to curve its surface (called meniscus). This is not the first patent of this kind filed by Canon (1 | 2). Hard to say if such a lens will come to the market any time soon.

  • Patent Publication No. 2014-145883
    • Published Date 2014.8.14
    • Filing date 2013.1.29
  • Example 4
    • Zoom ratio 2.07
    • Focal length f = 10.30-13.12-21.35mm
    • Fno. 3.23-3.62-4.63
    • Half angle ω = 52.86-46.03-32.50 °
    • Image height 13.60mm
    • The overall length of the lens 135.13-133.91-135.09mm
    • BF 0.15mm
  • Canon patents
    • And by varying the shape of the boundary surface, thereby changing the refractive power
    • Zooming, and has a refractive power element is positive, the element is negative
    • And reduce the variation of the curvature

[via Egami]

October 20, 2014
Posted in patents

Canon Patent For 2x Teleconverter With Diffractive Optical Element

Canon PatentCanon Patent

Egami (translated) spotted a patent filed by Canon for a 2x teleconverter which incorporates a diffractive optical element.

  • Patent Publication No. 2014-145870
    • Published Date 2014.8.14
    • Filing date 2013.1.29
  • Example 1
    • Focal length -109.09mm
    • Magnification 2.00x
    • 4 group 9-lens configuration
    • One plane diffraction plane (the first group)
  • Master lens
    • Focal length f = 293.76mm
    • Fno. 2.91
    • Half angle ω = 4.21 °
    • Image height Y = 21.64mm
    • The overall length of the lens 275.41mm
    • BF 53.79mm
    • 15 sheets 11 groups lens configuration
    • Protective glass 1
    • Rear filter 1
    • UD 2
    • Fluorite 1
  • Canon patents
    • I and the diffraction plane cemented surface of the cemented lens closest to the object side
    • This arrangement can suppress the flare

[via Egami]

October 18, 2014
Posted in patents

Canon Patent To Automatically Select Best Photos From Burst Mode (and save them in RAW)

Canon Patent

As usual, machine translated patents are hard to grasp. Feel free to correct me in the comment section if you think I got it wrong. I will edit the post if I was wrong.

Egami (translated) spotted a patent filed by Canon for an algorithm that selects the best shots from burst mode, and saves these pics in RAW. The not so good pics are kept in JPG format. This technology appears to be particularly interesting for cameras with high fps (frames per second), like the EOS 7D Mark II. Note: I think the patent refers to burst mode, though the machine translation gives back the term “panning”.

  • Patent Publication No. 2014-150370
    • Published Date 2014.8.21
    • Filing date 2013.1.31
  • Canon patents
    • In panning, and evaluates the shooting each image, and automatically select whether to record in both RAW and JPEG
    • The subject is or is included, evaluation method, contrast, etc.

[via Egami]


October 15, 2014
Posted in patents

Canon Patent For Variable Diffusion Focusing Screen (Update: looks like focus peaking in OVF)

Canon Patent

Thanks Wade for confirming my first thought.

Edit: it looks as if the technology described in the patent provides a sort of focus peaking in the optical viewfinder. Cool.

Egami (translated) spotted a patent filed by Canon for a variable diffusion focusing screen.

The technology in the patent highlights sharp areas and helps to see how much depth of field you have (for instance at larger apertures).

  • Patent Publication No. 2014-191184
    • Published Date 2014.10.6
    • Filing date 2013.3.27
  • Canon patents
    • Spreading factor variable finder screen
    • First diffusion rate
      • Brightness priority
      • Setting of low diffusivity and high transmittance
    • Second diffusion rate
      • Blur priority
      • Setting of high diffusivity and low transmittance
    • The partially changed spreading factor according to the focusing range


September 28, 2014
Posted in patents

Canon Patent For Better Cooling Of Electronics

Canon Patent

Egami (translated) spotted a patent filed by Canon that uses more of the DSLR body as a heat sink. This should help to cool down the electronics and possibly also the sensor. Could also be useful for 4k video processing.

  • Patent Publication No. 2014-171141
    • Published Date 2014.9.18
    • Filing date 2013.3.5
  • Canon patents
    • , An electric path for heat imaging devices , electric heating member group, member boric mount ring portion (heat sink) heat to low thermal conductivity of the resin, and the order of the mount ring