What is the New HD Coating? An Official Explanation

Well, the old Pentax web domain link didn't work anymore. So, I need to search for it again! After some hard finding, here it is! >:-(

http://www.ricoh-imaging.co.jp/english/news/2012/20120911_8.html



So, it reflects less (claimed a 50% improvement) and the coated surface is harder. And it also says that the HD coating is "almost as good" as the last nano-tech Pentax original Aero Bright