Sony has a new patent for phase detection and contrast detection autofocus systems. See the detailed explanation over at Imaging-resource:
"A recent patent publication from Sony shows off a new technology that could improve low-light autofocus performance in mirrorless cameras that use phase-detection or hybrid autofocus systems with the help of uniquely shaped microlenses atop individual pixels.
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Could this mean mirrorless cameras might soon focus as well as current SLRs? Possibly. Phase-detection autofocus in mirrorless systems will perform far better with less light than ever before if this patent comes to fruition. However, single-sensor phase-detection autofocus will likely never focus quite as fast as cameras with a dedicated phase-detection systems, especially taking into account that any sensor benefits that work on mirrorless sensors can also likely be used on SLRs' dedicated autofocus sensors."
