Sigma Patents for 24-70mm F2.8, 28-70mm F2.8 and 28-85mm F2.8

Sigma has filed new patents for 24-70mm f/2.8, 28-70mm f/2.8 and 28-85mm f/2.8 Lenses for Sony E-mount full frame mirrorless cameras.

[Publication number] P2022067732
[Publication date] May 9, 2022
[Patent application title] Large-diameter zoom lens

Example 1 (24-70mm F2.8)

Zoom ratio 2.75 Wide-
angle intermediate telephoto
focal length 24.72 39.76 67.98
F number 2.92 2.92 2.92
Full angle of view 2ω 85.24 56.96 34.33
Image height Y 21.63 21.63 21.63
Lens total length 135.00 145.60 171.09
Back focus 17.6206 17.6036 17.5749

Example 3 (28-70mm F2.8)

Zoom ratio 2.35 Wide-
angle intermediate telephoto
focal length 28.81 40.01 67.69
F number 2.92 2.92 2.92
Full angle of view 2ω 75.92 56.06 33.85
Image height Y 21.63 21.63 21.63
Lens total length 120.04 126.08 142.66
Back focus 19.6292 19.5884 19.6020

Example 4 (28-85mm F2.8)

Zoom ratio 2.90 Wide-
angle intermediate telephoto
focal length 28.79 49.98 83.51
F number 2.92 2.92 2.92
Full angle of view 2ω 75.61 45.42 27.77
Image height Y 21.63 21.63 21.63
Lens total length 135.02 146.97 164.94
Back focus 17.6146 17.5433 17.5817