Canon publishes patent number 20190302404 in the United States , The patent involves two lenses, RF 70-240mm F4 IS USM and RF 70-300mm F4-5.6 IS USM. In the next 1-2 months, Canon is expected to release the RF 70-200mm F2.8 L IS USM lens to complete the construction of the RF large ternary lens combination. From the exposed patents, Canon is currently focusing on the research and development of a telephoto zoom lens with a more affordable price.
Canon RF 70-240mm F4 IS USM lens patent details:
Focal length: 72.10mm 131.78mm 242.00mm aperture: 4.10 4.10 4.10 Half angle of view: 16.70 degrees 9.32 degrees 5.11 degrees Image height: 21.64mm 21.64mm 21.64mm Lens length: 147.22mm 176.39mm 210.90mm Back focal length: 12.95mm 25.54mm 36.63mm
Canon RF 70 -300mm F4-5.6 IS USM lens patent details:
Focal length: 72.10mm 144.31mm 289.00mm aperture: 4.60 5.68 5.88 Half angle of view: 16.70 degrees 8.53 degrees 4.28 degrees Image height: 21.64mm 21.64mm 21.64mm lens length : 136.41mm 169.48mm 201.14mm Back focal length: 12.95mm 28.75mm 42.22mm
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