Patent ID: 7280461

Claim:
An optical recording and reproduction medium in which pits corresponding to recording information are formed along a recording track comprising: auxiliary pits formed in at least a portion of spaces between said pits which are adjacent along said recording track direction, wherein when the depth of said pits is d 1 and the depth of said auxiliary pits is d 2 , the relation d 1 ≧d 2 is obtained; both edge portions of said auxiliary pits along said recording track are shaped as simple convex curves; and when a refractive index of a medium from a light entering surface on said optical recording and reproduction medium to said pits is n, a wavelength of incident light for reproduction used to reproduce the recording information of said pits is λ, a phase depth of said pits is x 1 , and a phase depth of said auxiliary pits is x 2 , then the relations λ/13.06 n≦x 1≦λ/5.84 n and λ/16.14 n≦x 2 ≦x 1 are obtained.