A main information area 31 capable of recording an information signal and a subsidiary information area 32 for recording subsidiary information that is different from the information signal are divided in one principal plane direction of a substrate, and an information layer for recording the information signal in the main information area 31 is provided also in the subsidiary information area 32, and medium identification information for distinguishing the medium optically is recorded in the information layer of the subsidiary information area 32 without changing the shape of the information layer. As a result, the medium identification information can be recorded in an optical recording medium 1 stably. In particular, the initialization of a phase change type optical recording medium and the recording of the medium identification information can be performed at the same time, so that the production process can be simplified, and the production costs can be reduced.

 
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> Optically active color filter

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