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Reduction of phase error on phase-only volume-holographic disc rotation with pre-processing by phase integral
Optics Express
|September 29, 2020
Summary
Phase errors in rotating volume holographic storage discs decrease bit error rates. A novel pre-processing method using phase integral effectively reduces retrieval errors, improving data accuracy for holographic storage systems.
Area of Science:
- Optical Engineering
- Data Storage Technologies
- Holography
Background:
- Volume holographic storage (VHS) offers high-density data storage.
- Phase-only signals in VHS are susceptible to phase errors during readout.
- Disc rotation or displacement introduces significant phase errors, degrading signal quality.
Purpose of the Study:
- To investigate the impact of disc rotation and displacement on phase error in VHS.
- To develop a novel method for mitigating phase errors during the readout process.
- To enhance the bit error rate (BER) performance of phase-only signals in VHS.
Main Methods:
- Theoretical calculation and experimental observation of phase error in a rotating VHS disc.
- Application of double-frequency shearing interferometry for phase signal retrieval.
- Development and implementation of a pre-processing technique involving phase integral along the shearing direction.
Main Results:
- Disc rotation and displacement were observed to introduce substantial phase errors.
- These errors significantly decrease the bit error rate of phase-only signals.
- The proposed phase integral pre-processing method effectively reduces phase retrieval errors.
Conclusions:
- Phase errors are a critical challenge in volume holographic storage systems.
- The novel phase integral approach offers a viable solution to mitigate these errors.
- This method is beneficial for improving the reliability of double-frequency shearing interferometry in VHS readout.
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