This is exactly what Apple introduced with the iPhone 6, in case anyone was wondering.
Nope, Apple introduced a different technology. http://thenextweb.com/apple/2014/09...us-pixels-sensor-optical-image-stabilization/
Dual-pixel is technology developed by Canon for their DSLRs. It would appear Samsung have licensed it from Canon.
http://www.canon.co.uk/for_home/product_finder/cameras/digital_slr/dual_pixel_cmos_af/
Dual pixel is pretty damn amazing. And it is amazing Samsung have managed to put it into a device as slim as a mobile phone.