Optical memory reproduction apparatus and incidence positioning method for read light thereof
US7505644B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2004 |
| Grant date | Mar 17, 2009 |
| Priority date | — |
| Expiry date | Sep 3, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2001/2615
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical memory medium (2) has cores (21) each constituting a planar optical waveguide and clads (22) sandwiching each core, and has a data image (203) in which data is recorded as a scattering factor and a pair of positioning marks (201, 202) which are scattering factors required for positioning at an interface between a core (21) and a clad (22) or in the core (21). A read light (103) travels while spreading in the core (21) and scatters and interferes by the data image (203), and data is reproduced from a data reproduction light (1031) generated by this scattering and interference. A pair of positioning lights (101, 102) are caused to enter the core (21) with offsets with respect to the read light (103) in opposite directions along a thickness direction of the core (21), and scatter and interfere at the pair of positioning marks (201, 202). Incidence positions of the lights emitted from a light source (11) with respect to the core (21) in a thickness direction of the core (21) are controlled based on intensities of a pair of positioning mark lights (1011, 1021) generated by this scattering and interference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.