Information recording and reproducing apparatus, information recording medium and information recording apparatus

申请公布号：: US7606117(B2)
申请号：: US20060387686
申请日期：: 2006.03.24
申请公布日期：: 2009.10.20
申请人：: CANON KABUSHIKI KAISHA
发明人：: MIZUTANI NATSUHIKO;YAMADA TOMOHIRO
分类号：: G11B11/00
主分类号：: G11B11/00
摘要：: An information recording and reproducing apparatus including a recording medium that includes at least a substrate, a reflection layer disposed on the substrate, and a recording layer disposed so as to interpose the reflection layer between the substrate and the recording layer, and a near-field optical head, disposed close to the recording medium, for irradiating the recording medium with near-field light to effect recording and reproduction of information. The near-field optical head includes a light-blocking metal film which includes a dielectric base material provided with a small opening and which is disposed opposite to the reflection layer disposed on the substrate, so that the light-blocking metal film and the reflection layer constitute an optical resonator to increase intensity of the near-field light. The optical resonator satisfies the following resonance condition: 4piL/lambda+phi1+phi2=2mpi, wherein L represents an optical path between a bottom surface, of the near-field optical head, at which the light-blocking metal film is disposed; lambda represents a wavelength in a vacuum of a light source used in the near-field optical head; phi1 represents a phase shift due to reflection by the light-blocking metal film; phi2 represents a phase shift due to reflection by the reflection layer; and m represents a positive integer.