Patent ID: 8318329

Claim:
A radiation-selective absorber coating ( 20 ) for an absorber tube ( 13 ) of a parabolic collector ( 10 ), said radiation-selective absorber coating ( 20 ) comprising a reflective layer ( 21 ) that reflects in an infrared range, at least one absorption layer ( 22 ) arranged above the reflective layer ( 21 ), and an antireflection layer ( 23 ) arranged above said at least one absorption layer ( 22 ), said reflective layer ( 21 ) being arranged on at least two barrier layers ( 24 a ) and ( 24 b ); wherein said at least two barrier layers comprise a first barrier layer ( 24 a ) and a second barrier layer ( 24 b ); wherein said second barrier layer ( 24 b ) of said at least two barrier layers is arranged between said first barrier layer ( 24 a ) and said reflective layer ( 21 ) and said second barrier layer ( 24 b ) consists of a SiO x compound, wherein x is from 1 to 2; wherein said first barrier layer ( 24 a ) of said at least two barrier layers consists of an oxide obtained thermally; and wherein said at least one absorption layer ( 22 ) consists of a cermet material.