Optical information recording medium comprising a first layer having a phase that is reversibly changeable and a second information layer having a phase that is reversibly changeable

An optical information recording medium comprising:

• a first information layer including a first recording layer whose phase is reversibly changeable between a crystalline state and an amorphous state by exposure to a light beam, said first recording layer having an absorptance A1c when in the crystalline state, said first recording layer having an absorptance A1a when in the amorphous state;
• and
• a second information layer including a second recording layer whose phase is reversibly changeable between a crystalline state and an amorphous state by exposure to the light beam, said second recording layer having an absorptance A2c when in the crystalline state, said second recording layer having an absorptance A2a when in the amorphous state,
• wherein A1a<A1c and A2a<A2c.

An optical information recording medium comprising:

• a first recording layer to which information can be recorded by exposure to a first light beam, said first recording layer including a non-recorded region having pre-recorded marks formed thereon and a recording region not having pre-recorded marks formed thereon;
• and
• a second recording layer to which information can be recorded by exposure to a second light beam which transmits through said first recording layer,
• wherein said recording region is capable of having recorded marks, which correspond to the information to be recorded by exposure to the first light beam, formed thereon,
• wherein said non-recorded region has a transmittance substantially the same as said recording region, and
• wherein a total area of said non-recorded region is at least 20 percent of a total area of said recording region.