Patent ID: 8565057

Claim:
A multilayer optical recording medium, which includes an N number of interfaces capable of reflecting incident light, wherein the multilayer optical recording medium satisfies a condition that a difference |S j to k −S l to m | between a total sum S j to k of a thickness of spacers formed between the interface Lj and the interface Lk and a total sum S l to m of a thickness of spacers formed between the interface Ll and the interface Lm is larger than nλ/NA 2 , provided that each of an M number of interfaces selected from the N number of interfaces is defined as Li, and j<k≦l<m≦M is set, when light having a wavelength λ is collected to an objective lens having a numerical aperture NA with an interface Lj being a target, regarding an interface Lk, an interface Lm, and an interface Ll, which cause stray light due to three-times reflections via Lk or Ll to Lm to Ll or Lk, and the interface Lj, wherein N≧5, wherein M≦N, wherein i=0, 1, . . . , M, where, as a value of i becomes smaller, the layer in which the interface is formed becomes lower as viewed from an uppermost surface as a light incident surface, and wherein n is a refractive index of any of the spacers.