Use of feedback error and/or feed-forward signals to adjust control axes to optimal recovery position of hologram in holographic data storage system or device
US8446808B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 2009 |
| Grant date | May 21, 2013 |
| Priority date | — |
| Expiry date | Jun 10, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/083
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for adjusting at least one alignment control axis of a holographic data storage system or device to or towards a sufficiently optimal recovery position for recovery of a hologram based on a derived feedback error signal and/or a derived feed-forward signal. For the next hologram in the sequence, the derived feedback error signal estimates the direction and magnitude of misalignment of the at least one alignment control axis for one or more previously recovered holograms based on alignment-indicating data. The derived feed-forward signal estimates an optimal alignment value for the at least one alignment control axis for one or more holograms based on recording and recovery operating condition data for the holograms. An iterative alignment procedure may also be used to derive a feedback error signal for one hologram.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.