Patent ID: 7505644

Claim:
An optical memory reproduction apparatus which reproduces data from an optical memory medium comprising: cores each of which constitutes a planar optical waveguide, and clads which sandwich each core, and having: a data image in which data is recorded as a scattering factor; and a pair of positioning marks which are respectively scattering factors required for positioning, at an interface between a core and a clad or in the core, the optical memory reproduction apparatus comprising: a light source which emits: a read light which is caused to enter the core from an end surface of the optical memory medium, travels while spreading in the core, and is coupled with the core to form an optical coupling area in such a manner that the optical coupling area includes the data image; and a pair of positioning lights which are caused to enter the core with offsets with respect to the read light in opposite directions along a thickness direction of the core, travels in the core, and are coupled with the core to form optical coupling areas in such a manner that the optical coupling areas include the pair of positioning marks; a data reproduction light imaging element which receives a data reproduction light generated due to scattering and interference of the read light in the data image; a data reproducing unit which reproduces data imaged by the data reproduction light imaging element; a positioning mark light receiving element which receives a pair of positioning mark lights generated due to scattering and interference of the pair of positioning lights in the pair of positioning marks; and a light source position control unit which controls an incidence position of the read light with respect to the core in the thickness direction thereof based on intensities of the pair of positioning mark lights detected by the positioning mark light receiving element.