Patent ID: 8213287
Filing Date: 2012-07-03
Classification: G11B

Abstract:
1. A holographic data recording and/or reproducing apparatus comprising an optical pickup that emits light to a reflective holographic data storage medium in which a substrate, a reflection layer, a recording layer, and a cover layer are sequentially stacked, wherein the optical pickup comprises: a first light source unit to emit, during a recording operation, a signal beam having a first polarization and a reference beam having a second polarization different from the first polarization along a same optical path; and a main lens unit to record data by using an interference pattern formed in a direction along a depth of the holographic data storage medium around a focal point on the recording layer, and having a refractivity that varies according to a polarization of a passing light, so as to cause the signal beam to be reflected from the reflection layer then be focused on the focal point and to cause the reference beam to pass through the cover layer of the holographic data storage medium then be directly focused on the focal point, wherein the signal beam and the reference beam have a same optical path in the main lens unit.