The hybrid disc works by making the Blu-ray layer act like a two way mirror, reflecting enough light for Blu-ray playback, but letting enough light through for HD DVD operation.

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The three-layer version, in particular, provides a unique hybrid power supply.

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The Intra-Hybrid Blu-ray Disc (IH-BD) incorporates a single BD-ROM layer and a single BD-RE layer so as to enable the user to view, but not overwrite, critical published data while providing the flexibility to include relevant personal data on the same physical disc.

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The first problem was that the equity layer was far too thin, and that banks were wary of imposing losses on holders of hybrid debt.

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