It has nothing to do with a new mirror. It is software they are patenting. Two of the problems with pellix mirrors are
Abberation from light passing thru a very thin piece of glass which can warp easily
ghosting, where reflections from both the front and rear surface of the mirror result in a faint double image. Sonys mirrorless cameras had this issue, but it is better corrected in the newest model.
Its all done in software.
Here is a better translation of the problem.
However, since the thin film mirror or the glass mirror of 0.2 mm or less which is a delicate optic is used in the patent documents 1, handling is difficult. The thin film mirror itself is expensive, and if it is going to constitute the mechanism in which a thin film mirror or a glass mirror of 0.2 mm or less is held, maintaining profile irregularity, it is difficult to provide a small and inexpensive camera.
Then, this invention provides a small and inexpensive imaging device, controlling image degradation generated by the internal reflection of a half mirror.