Patent ID: 6083598
Filing Date: 2000-07-04
Classification: B29C,B29D,B29L,G11B,Y10S,Y10T

Abstract:
A multi-substrate disk comprising:a first disk-shaped substrate having a first information recording layer formed thereon, said first substrate having a predetermined outer diameter, a predetermined inner diameter, and a thickness of about 0.6 mm;a second disk-shaped substrate, said second substrate having the predetermined outer diameter, the predetermined inner diameter, and a thickness of about 0.6 mm; andan intermediate layer provided on said first information recording layer, and having a prescribed thickness;a second recording layer formed on said intermediate layer so that said intermediate layer is between said first and second recording layers;wherein a refractive index of said first substrate with respect to a sum of the thickness of said first substrate and intermediate layer is selected from the following sets of parameters:refractive index=1.45 with the sum of the thickness of 0.653 mm;refractive index=1.56 with the sum of the thickness of 0.640 mm;refractive index=1.65 with the sum of the thickness of 0.640 mm;refractive index=1.65 with the sum of the thickness of 0.550 mm;refractive index=1.56 with the sum of the thickness of 0.550 mm; andrefractive index=1.45 with the sum of the thickness of 0.563 mm.