New patents for a Sigma 28mm f/1.4 DG DN and 14mm f/2 DG DN lens and Tamron 90mm macro

Asobinet spotted a newly published Sigma patent that described the optical design of the 28mm f/1.4 DG DN and 14mm f/2 DG DN lenses.

• Focal length: 14.48
• F-value: 2.07
• Angle of view: 114.27
• Image height: 21.63
• Total length: 128.00
• Back focus: 20.0000

• Focal length: 27.50
• F-value: 1.46
• Angle of view: 76.53
• Image height: 21.63
• Overall length: 113.50
• Back focus: 21.7787

Digicameinfo spotted a patent for two Tamron 90mm lenses:

• 90mm F2 (1x magnification)
• 90mm F2.8 (2x magnification)

Asobinet spotted a Tamron prime lens patent:

• 16mm f/2.8