The membrane is a mechanical element. While LC lenses will no change their shape. The problem with liquid crystals though is that they are birefringent. The

The membrane is a mechanical element. While LC lenses will no change their shape. The problem with liquid crystals though is that they are birefringent. The effect look like as if different focal planes have different (and quite large) apertures. I believe this is where the company in questions uses software to mask it some way. The benefit of liquid crystal lenses over other electrically tunable lenses is their thickness. Other tunable lens materials don't have birefringence, but their electro/thermo/piezi-optical effect is much, much weaker, and large size. The later is improving with each year. Usable solid TAG lenses may get below 1cm.