Patent ID: 8526284

Claim:
A multilayer optical recording medium comprising: a plurality of interfacial surfaces configured to reflect an incident light beam, neighboring ones of the interfacial surfaces having a spacer therebetween; wherein, when a light incident surface side is an upper surface side, a different thickness layer unit including the spacers having different thicknesses arranged sequentially is disposed on the lowermost layer side and the spacers each having a thickness different from the thickness of any one of the spacers arranged in the different thickness layer unit are sequentially arranged above the different thickness layer unit, the different thickness layer unit includes three types of spacer having different thicknesses arranged therein, a plurality of equal-thickness layer units each including spacers having the same thickness sequentially arranged therein are formed above the different thickness layer unit, and the thickness of the spacers arranged in one of the equal-thickness layer unit differs from the thickness of the spacers arranged in any one of the other equal-thickness layer units.