Canon has just filed a new patent of EF-S 100-300mm F4-5.6 IS lens. This new lens is a super telephoto zoom lens for Canon APS-C DSLRs.
Patent Publication No. 2015-138178
Filing date 2014.1.23
Focal length 102.00 195.50 291.20mm
F-number 4.16 5.14 5.88
Half angle of 7.63 4.00 2.69 °
Positive and negative positive and negative four-group zoom
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