摘要 |
<p>An optical information medium ( 20 ) for erasable recording by means of a laser-light beam ( 10 ) is provided. A substrate ( 1 ) holds a stack ( 2 ) of layers with a phase-change recording layer ( 5 ) between a first dielectric layer ( 4 ) and a second dielectric layer ( 6 ). A light-absorptive layer ( 7 ) is present proximate the recording layer ( 5 ) and is made of a compound of the formula QR<SUB>x</SUB>, in which Q is the element Si, Ge, Ti, Zr, Hf, Nb or Ta, R is the element O or N, and 0<x<=2.5, in order to achieve that 0.8<A<SUB>c</SUB>/A<SUB>a</SUB><1.50, IN WHICH A<SUB>c </SUB>and A<SUB>a </SUB>are the respective quantities of laser-light absorbed in the recording layer ( 5 ) in the crystalline state and the amorphous state at a laser-light wavelength selected from a range of 350-450 nm. Thus high data rates and low data jitters are achieved at this short wavelength range by tuning x to an optimal value during manufacture of the optical information medium.</p> |