Patent ID: 7573803

Claim:
An optical recording disc constituted so that data can be recorded therein and reproduced therefrom by converging a laser beam having a wavelength λ of 390 nm to 420 nm thereonto using an objective lens having a numerical aperture of 0.7 to 0.9, the optical recording disc comprising a substrate, a third dielectric layer formed on the substrate and having a thickness of 10 nm to 140 nm, a light absorbing layer formed on the third dielectric layer and having a thickness of 5 nm to 100 nm, a second dielectric layer formed on the light absorbing layer and having a thickness of 5 nm to 100 nm, a decomposition reaction layer formed on the second dielectric layer, having a thickness of 2 nm to 20 nm and containing noble metal oxide as a primary component, a first dielectric layer formed on the decomposition reaction layer, and a light transmission layer formed on the first dielectric layer and having a thickness of 10 μm to 200 μm and being constituted so that when it is irradiated with the laser beam from the side of the light transmission layer, the noble metal oxide contained in the decomposition reaction layer as a primary component is decomposed into a noble metal and oxygen so that a bubble pit is formed in the decomposition reaction layer by thus generated oxygen gas and fine particles of the noble metal precipitate into the bubble pit, thereby forming a recording mark in the decomposition reaction layer.