Optical data storage (ODS) is a low-cost and high-durability counterpart of traditional electronic or magnetic storage. As a means of enhancing ODS capacity, the multiple recording layer (MRL) method is more promising than other approaches such as reducing the recording volume and multiplexing technology. However, the architecture of current MRLs is identical to that of recording data into physical layers with rigid space, which leads to either severe interlayer crosstalk or finite recording layers constrained by the short working distances of the objectives. Here, we propose the concept of hybrid-layer ODS, which can record optical information into a physical layer and multiple virtual layers by using high-orthogonality random meta-channels. In the virtual layer, 32 images are experimentally reconstructed through holography, where their holographic phases are encoded into 16 printed images and complementary images in the physical layer, yielding a capacity of 2.5 Tbit·cm−3. A higher capacity is achievable with more virtual layers, suggesting hybrid-layer ODS as a possible candidate for next-generation ODS.
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