Egami spotted a new patent filed by Sigma. The new patent describes the Sigma 17-55mm f/2.8 OS lens designed for DSLR cameras with APS-c sized sensors.
Sigma has several patents filed for a standard APS-C zoom lens with fixed aperture as the Sigma 16-50mm f/2.8 without OS also another pending on the list.
As we know the company already has the very popular 17-70mm f/2.8-4 lens and the Sigma 17-55mm f/2.8 OS will sure be a very good option to choose as fixed aperture of 2.8. See the patent details below.
Sigma 17-55mm f/2.8 OS Lens Patent
Explanation and self-interpretation of the patent literature
- Patent Publication No. 2014-209226
- Published 2014.11.6
- Filing date 2013.3.29
- Example
embodiment Example Zoom ratio Focal distance Fno. Angles of view Overall length of the lens Lens constitution Aspheric surface SLD One 10.50 18.45-70.00-193.80 3.48-5.52-6.48 77.13-22.40-8.28 115.02-157.27-190.83 13 group 18 sheets 5-sided four One Two 3.90 17.51-35.00-68.47 4.09-4.11-4.13 79.84-43.58-23.11 107.44-120.26-155.63 13 group 18 sheets 4 face three 0 Three 3.14 17.52-30.00-54.94 2.92 80.06-50.16-28.52 117.23-128.48-159.55 12 groups 18 sheets Six-sided four 0 Four 2.77 70.01-135.00-193.80 5.09-5.34-5.98 22.69-11.87-8.29 125.88-147.53-160.88 13 group 17 sheets 0 Two Five 2.77 70.01-135.00-193.80 4.90-4.96-5.98 22.63-11.81-8.23 126.13-148.31-161.13 11 group 16 sheets 0 Two Image height Y = 14.20mm, inner focus, anti-vibration
via Egami