At least one information layer including a recording layer contains a material that can exhibit a transition between two optically different states in response to irradiation with a laser beam as a main component is provided on a substrate, and the material is configured so as to exhibit an energy gap ranging from 0.9 eV to 2.0 eV in the amorphous state. The information layer is configured to have a light transmittance of not less than 30% when irradiated with a laser beam having a wavelength ranging from 300 nm to 450 nm. It is possible to achieve excellent recording/reproduction, even if a plurality of recording layers are provided in the recording medium, when this medium is irradiated with a laser beam with a wavelength in the foregoing range from one side of the medium.

 
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