Our sister site Photorumors found an interesting patent application the other day. It seems Fujifilm might have a Fujinon XF13mm f1.8 or Fujinon XF20mm f1.8 in the works, but the translation is imperfect. Maybe this patent explains the significant savings on the Fujinon XF 14mm F2.8 R. We will let you know when we know.
Fujifilm 20mm F1.8 (equiv.) Patent of Optical technology and lens design]
Description, self-interpretation of the patent literature
- Patent Publication No. 2016-95461
- Published 2016.5.26
- Filing date 2014.11.17
- Example 1
- Focal length 1mm
- Bf 2.08 – 2.05 – 1.94
- FNo 1.90 -. 1.92 – 2.00
- Full angle of view 2ω 95.2 – 94.4 – 91.2
- Lens configuration 9 groups 11 sheets
- ED 4
- Fujifilm patents
- Negative-positive ShiboTadashi, or negative-positive Shibomake
- Rear focus
From left to right, the spherical aberration, astigmatism, distortion, lateral chromatic aberration.
The focal length of the entire system seems to scale down the optical design values to be 1mm. By doing this, it will benefit not then understand the product under development in the same industry manufacturers.
So all the angle of view is 95.2 °, Will is considering the 20mm of 14mm (13mm) or for full-size for the APS-C. Back focus is so about 2mm, about 28mm of BF and to scale up to the APS-C, it will be BF of about 40mm and to scale up to full-size. Product will become a short BF, but for now does not mean must shorten the BF because mirrorless Fujifilm will result that the pursuit of optimization that can be considered.