There are seven examples in the patent request.
Minimum focal length is between 11.25mm an 11.29 mm. Maximum focal length is between 17.6mm and 17.7mm.
Maximum aperture is either f/2.8 (four examples) or f/2.9 (three examples).
There are basically two optical formulas with variants:
- three examples include 15 elements in 11 groups; their length at 11mm is around 8.9cm and they extend by 1.7mm to 4.7mm at 18mm.
- four examples include 16 elements in 11 groups; their length is around 9.8cm at 11mm and changes only very slightly at 18mm.
All examples include three aspheric elements: one or two (depending on whether 16/11 or 15/11) in the first element group, named G1, and two or one in the fourth element group, named G4.
G1 moves a bit when zooming in from 11mm to 18mm: towards the subject for six examples out of seven, towards the image in one example. The second element group, named G2, also moves when zooming in, towards the subject. The third element group, named G3, also moves when zooming but its movement is more complex and varies from an example to another. G4 moves towards the subject when zooming in.
Focus is apparently done by moving some elements within G2.
Below is the optical diagram of an example with 16 elements in 11 groups.