Optical information recording medium
AssigneeTaiyo Yuden Co., Ltd.
InventorsEmiko Hamada, Yuji Arai, Yuaki Shin, Takashi Ishiguro
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Abstract
An optical information recording medium comprising a light transmitting substrate, a light absorptive layer overlaying the substrate to absorb a laser beam and a light reflective layer overlaying the light absorptive layer, wherein an optical parameter represented by .rho.=n.sub.abs d.sub.abs /.lambda. where n.sub.abs is the real part of the complex refractive index of the light absorptive layer, d.sub.abs is the thickness of the light absorptive layer and .lambda. is the wavelength of a reading laser beam, is 0.05.ltoreq..rho..ltoreq.0.6, and the imaginary part k.sub.abs of the complex refractive index of the light absorptive layer is at most 0.3.
Claims9
An optical information recording medium comprising a light transmitting substrate, a light absorptive layer having a complex refractive index comprised of a real part of said complex refractive index (n.sub.abs) and an imaginary part of said complex refractive index (k.sub.abs), said absorptive layer having a thickness (d.sub.abs), said light absorptive layer overlaying the substrate to absorb a laser beam and a light reflective layer overlaying the light absorptive layer, wherein an optical parameter represented by .rho.=n.sub.abs d.sub.abs /.lambda. where .lambda. is the wavelength of a reading laser beam, meets the inequality 0.05.ltoreq..rho..ltoreq.0.6, and the imaginary part k.sub.abs of the complex refractive index of the light absorptive layer is at most 0.3.
Dependencies are inferred from the claim text.