OPTICAL INFORMATION RECORDING MEDIUM

摘要

The present invention provides an optical information recording medium that can stably carry out the recording or reproducing of information with a simple structure. Since the optical information recording medium of this invention contains a photo-polymerization initiator with the evaporation temperature in the range of 140ºC-400 ºC, a recording light beam (L2c) is concentrated to heata portion in the vicinity of the focus (Fb) of the recording light beam (L2c). The heat volatilizes the photo-polymerization initiator, so that it can form bubbles. The bubbles are left as cavities in the recording layer (101) after the irradiation of the recording light beam (L2c) is completed and the area in the vicinity of the focus (Fb) is cooled down. When a reading-out beam (L2d) is irradiated to the bubbles, the difference between the bubble internal refractive index and the recording layer (101) refractive index as the bubble external one reflects the reading-out beam (L2d) and makes it possible to generate a returning beam (L3).