Patent ID: 7718952

Claim:
An information carrier comprising: a metal layer comprising at least one track comprising marks, the marks providing information for reading by a detector external to the information carrier, and the marks disposed within the at least one track, wherein light emitted by light means as light used for detection impinges on the marks, the light emitted by light means having a central wavelength (λ), the light means comprising a light source incident at an angle (Θ i ) upon the information carrier, and wherein the position of the information carrier can be derived from the position of the marks, wherein the marks comprise areas at least structured by first structures of a first lattice period (Λ), the first structures disposed on the back side of the metal layer and/or on the front side of the metal layer, wherein the lattice period (Λ) of the first structures satisfies the equation Λ=λ/((n p *−sin(Θ i )) or Λ=λ/(n p *+sin(Θ i )), where λ is the central wavelength of the light emitted by light means, Θ i is the angle of incidence on the information carrier of the light emitted by the light source, and n p * is the effective index of a plasmon mode along the metal layer.