The Sony RX100 Mk II, just like the original RX100, sports a lens that has a bright initial aperture of f1.8 at its widest setting, but that gets rather slow towards its tele end where the maximum aperture is a mere f4.9. This is not untypical for compact cameras, as making the aperture much wider would also result in an overall larger lens. Still, newly unearthed patents show that the next iteration of the series could sport a lens with a brighter aperture at the tele end.
Published by Egami, the patent sketches five different zoom lens designs for compact cameras sporting a 1″ sensor, and all of them are very similar to the lens inside the currect RX100 (Mk II). One design in particular looks like a potential candidate for an RX200 camera, sporting the same focal length range of 28-100mm equivalent, but a brighter aperture that goes from f1.8 at the wide-angle end to f2.8 at the tele end.
Another design is for a lens with a longer zoom range of 28-150mm, and an aperture range of f1.8-3.6, which is also relatively bright considering the longer focal length at the tele end. Both lens designs sport 12 elements, arranged into 10 groups in the shorter lens and 9 groups in the longer lens. Also discussed in the patent is the addition of a macro mode, which would allow for very short close-focusing distances.
The way we see it, both of these lens designs would make sense for a successor to the RX1oo Mk II. A brighter aperture at the tele end is something that many RX100 (Mk II) users have been calling for, so the first option would satisfy that department. But a slightly longer lens that provides extra reach could also find a liking with many customers, especially if its aperture at the telephoto end is as bright as described in the patent.