Canon Patent Application: EF-M 18-55 with variable field curvature

This patent application describes a lens that has variable field curvature and a reduction of spherical aberrations.  This is an APS-C mirrorless lens, as indicated by the image height of 13.66mm and the back focus of 11.55mm.

The full lens particulars are;

Focal distance 18.58 53.49 
F number        3.56  5.87 
Field angle    36.32 14.32 
Image height   13.66 13.66 
BF             11.55 11.55

Focal distance 18.54 53.37 
F number        3.5 5 5.86 
Field angle   36.39  14.36 
Image height  13.66  13.66 
BF            10.14  10.14 ​ 

Japan Patent Application 2018159876