Multivalued information reproducing method and multivalued information reproducing apparatus

摘要

A multivalued information reproducing apparatus includes: a light source which emits a linear polarized light having a prescribed polarization direction; a first optical system which generates a first linear polarized light and a second linear polarized light that have different polarization directions using the linear polarized light which is emitted from the light source and makes the two polarized lights input to an optical recording medium in which the polarization directions of recording lights are recorded as multivalued information; a second optical system by which light that passes the optical recording medium or light that is reflected by the optical recording medium is directed to a photo detecting portion in a state where the first linear polarized light and the second linear polarized light are separated; and a polarization direction judging portion which judges the polarization direction that is recorded in the optical recording medium based on amount of light of the first linear polarized light and amount of light of the second linear polarized light that are obtained by the photo detecting portion.