Canon filed a patent for a 300mm F2.8 IS ASPH lens.
According to the present invention, at the telephoto lens, a cemented lens and a non-spherical surface consisting of a glass material having an anomalous dispersion characteristic that used in the appropriate refractive power where appropriate, in the chromatic aberration of the correction and the entire optical system it is possible to achieve both of the reduction in size and weight to provide an optical system that has been made.
- Patent Publication No. 2016-173439
- Published 2016.9.29
- Filing date 2015.3.17
- Focal length 292.46
- F-number 2.91
- Angle of view 4.23
- Image height 21.64
- Overall length of the lens 273.95
- BF 60.81