Canon Patent For 70-400mm f/4.5-7.2 STM Lens For EOS M System

EOS M

Another patent for an EF-M lens that could go to market sooner or later. The fact that Canon is filing patents for EF-M lenses is a sign they are still committed to the system.

Egami (translated) spotted the patent. It’s a 70-400mm f/4.5-7.2 STM telephoto lens for APS-C mirrorless cameras, in the Canon world that’s the EOS M system (rumored to see a new entry soon).

Such a telephoto lens would allow Canon to catch up with the competition. All major mirrorless system manufacturer have telephoto lenses with similar range in offering. However, note that the patent does not refer to image stabilisation on the lens. Could be pretty difficult to shot shake-free at full extension and while hand-holding the camera.

  • Patent Publication No. 2014-228734
    • Published 2014.12.8
    • Filing date 2013.5.23
  • Example 3
    • Zoom ratio 5.58
    • The focal length f = 69.59-251.52-388.00mm
    • Fno. 4.68-6.30-7.00
    • Half angle ω = 11.11-3.11-2.02 °
    • Image height 13.66mm
    • Overall length of the lens 155.01-227.97-240.02mm
    • BF 15.81-37.15-46.87mm
    • Inner focus
[via Egami]

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

2014_225002_fig05

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.

Canon Patent to Increase Dynamic Range of Sensor

Canon Patent

Egami (translated) spotted a patent filed by Canon for a new sensor technology that expands the dynamic range of the sensor with a thin polysilicon layer applied on top of the photodiode layer of a sensor.

As far as I understand the patent, the polysilicon layer’s thickness is not the same for all the underlaying photodiodes. This influences the sensitivity of the photodiodes through the transmittance of light, which is attenuated by the film according to its thickness. The result are pixels (=photodiodes) with different light sensitivity.

Looking at the image above, it seems that there is one pixel with a thicker layer for each pixel with a thinner layer. The layer thickness appears to act on the the exact area where the photodiode detects the incoming photons.

An interesting patent that points to a new sensor technology. Hard to say if this tech will show up soon, for instance in the again rumored high megapixel cameras expected for 2015.The technology described in the patent does not refer to a given class of sensors, nor to a sensor size. It’s a technology that could find its way in any future Canon sensor.

Canon sensors are often critiqued for having a dynamic range below the competition, and thus getting lower DxOMark scores for their sensors. It appears Canon is going to address the issue.

Machine translated patent description:

  • Patent Publication No. 2014-175553
    • Published 2014.9.22
    • Filing date 2013.3.11
  • Canon patent
    • Optical attenuation film is arranged by polysilicon over the photoelectric conversion portion
    • Transmittance of light depends on the optical attenuation film is its thickness, thickness varies depending on the pixel
    • Small pixel transmittance is, the opening area is small
    • RGB any of the color filter
    • Transmittance R <G <B
[via Egami]

Black Friday deals here.

Canon Patent for 11-24mm f/3.5-4.5 Lens

2014_182180_fig05

Egami (translated) spotted a patent filed by Canon for an 11-24mm f/3.5-4.5 lens.

Machine translated patent description:

  • Patent publication number
    • Release date
    • Filing date
  • Example 3
    • Zoom ratio 2.07
    • Focal length 11.61-15.50-24.07mm
    • Fno. 3.63-3.96-4.69
    • Half angle ω = 49.64-41.38-29.58 °
    • Image height Y = 13.66mm
    • Overall length of the lens 133.0-129.1-133.3mm
    • BF 3.26mm
    • Negative positive and negative positive 4-group zoom
    • Inner focus (Lf part of the first group)
  • [0016]According to the present invention has a high optical performance over the entire object distance range, yet fast focusing easy zoom lens and optical system is obtained.
  • [0035]And at the same time using a low dispersion material in the material of the focus lens in the present invention, the lateral magnification of the focusing lens unit that corresponds to the drive amount during focusing, by appropriately setting the refractive index and Abbe number of the material and the like of the focus lens, and focus I have to reduce the aberration fluctuations of the time.

Canon Patent for 70-300mm f/4-5.6 Lens

Canon Patent

Egami (translated) spotted another patent filed by Canon.

The patent refers to a 70-300mm f/4-5.6 lens. As Egami notes, it’s a bit early for a replacement of the EF 70-300mm F4-5.6L IS.

Patent description (machine translated):

  • Patent Publication No. 2014-186098
    • Published 2014.10.2
    • Filing date 2013.3.22
  • Example 4
    • Zoom ratio 4.02
    • Focal length f = 72.20-135.09-289.98mm
    • Fno. 4.19-4.63-5.86
    • Half angle ω = 16.68-9.10-4.27 °
    • Image height Y = 21.64mm
    • Overall length of the lens 183.25-214.28-237.12mm
    • BF 43.12-49.21-66.05mm

Canon Patent