Information recording/reproducing apparatus that determines the number of recording layers of an information recording medium

摘要

An information recording/reproducing apparatus of the present invention includes: a light source for emitting a first light beam having a predetermined light power P_pre; a determination section for determining the number of recording layers included in the information recording medium; a light beam transmission adjustment section for adjusting the quantity of the first light beam transmitted therethrough; and a light condensing section for condensing the first light beam on the information recording medium. When the information recording medium has one recording layer, the adjustment section adjusts the predetermined light power P_pre so as to be a first light power P₁. When the information recording medium has two recording layers, the adjustment section adjusts the predetermined light power P_pre so as to be a second light power P₂. The predetermined light power P_pre, the first light power P₁, and the second light power P₂ satisfy the relationship of P₁2<=P_pre.