A new Canon patent application for two lenses featuring Canon's new silent USM zoom technology…
Canon Patent: More Pancake By Canon (45mm, 40mm, 35mm, 28mm, all f/2.8)
Japanese site Egami (translated) spotted new patents filed by Canon. All are for f/2.8 pancake lenses: 45mm, 40mm, 35mm, 28mm. Canon has two pancake lenses in their line-up: the EF 40mm f/2.8 STM and the EF-M 22mm f/2 STM
- Patent Publication No. 2013-137411
- Publication date 2013.7.11
- Filing date 2011.12.28
- Example
embodiment Focal length Fno. Half angle Configuration length Total length BF One 45.00 2.80 25.68 20.00 57.99 37.99 Two 39.00 2.80 29.02 23.50 62.50 39.00 Three 35.00 2.80 31.72 25.00 63.01 38.01 Four 28.00 2.80 37.69 27.00 65.00 38.00 Image height = 21.64mm
- Canon patent
- The longer the focus back a Gaussian type, field curvature occurs
- 2-group configuration positive positive, Gauss type
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