Optical information recording medium and optical information processing apparatus

Abstract

This invention allows super-resolution reproduction with which a better bER value is attainable, when information is recorded by a random pattern including a mark length not longer than a resolution limit, by use of a highly versatile signal decoding method. Information is recorded as marks and spaces coded by RLL(1,7) modulation, which each of the marks and spaces have one of a plurality of lengths, and 2T marks and 2T spaces of the marks and spaces being formed are shorter than 0.12 μm. An information recording layer ( 20 ) includes a reproduction film ( 21 ) and a reflective film ( 22 ) which are provided in this order from a side from which reproducing light is incident, which reproduction film is made of (i) zinc oxide, (ii) strontium titanate, (iii) titanium oxide, (iv) cerium oxide, or (v) a material including at least one of the (i) through (iv), and which reflective film is made of tantalum or titanium.

1 - 10 . (canceled) 
     
     
         11 . A method for reproducing an optical information recording medium by use of reproducing light having a wavelength of not less than 400 nm but not more than 410 nm, via an objective lens having a numerical aperture of not less than 0.84 but not more than 0.86, the optical information recording medium including an information recording layer to have information recorded thereon as marks and spaces coded by RLL(1,7) modulation of the optical information recording medium, wherein each of the marks and spaces has one of a plurality of lengths, and 2T marks and 2T spaces of the marks and spaces are formed to be shorter than 0.12 μm,
 the method comprising the steps of: 
 decoding a reproduction signal waveform, which is obtained by irradiating the optical information recording medium with reproducing light having a power of not less than 0.8 mW, in accordance with a PR(12221)ML decoding method; and 
 subjecting data having been decoded to error correction. 
 
     
     
         12 . A method for reproducing an optical information recording medium by use of reproducing light having a wavelength of not less than 400 nm but not more than 410 nm, via an objective lens having a numerical aperture of not less than 0.84 but not more than 0.86, the optical information recording medium including an information recording layer to have information recorded thereon as pits and spaces coded by RLL(1,7) modulation, wherein each of the pits and spaces has one of a plurality of lengths, and 2T pits and 2T spaces of the pits and spaces are formed to be shorter than 0.12 μm,
 the method comprising the steps of: 
 decoding a reproduction signal waveform, which is obtained by irradiating the optical information recording medium with reproducing light having a power of not less than 0.8 mW, in accordance with a PR(12221)ML decoding method; and 
 subjecting data having been decoded to error correction.