| 摘要 |
PURPOSE:To enable highly reliable large-capacity recording by binary recording and ternary recording by using a compound which increases and decreases in light transmissivity with the intensity of irradiation light for a recording film. CONSTITUTION:The recording film 2 made of azobenzene having a reaction group accompanied by optical anisotropy is provided on an acryl substrate 1 which is molded in a discoid shape. Information writing to the optical disk memory is performed by forming dots which are large in light transmissivity and dots which are small in the recording film 2 by using laser light while rotating the disk. At this time, a state of increased light transmissivity and a state of decreased light transmissivity are made to correspond to binary to enable the binary recording and the state of light nonemission is included to enable the ternary recording. For information reading, laser light which is reduced in intensity to an extent where the recording film 2 has no chemical variation is used as monitor light and transmitted light or reflected light from the recording film 2 is detected by a photosensor. Consequently, the capacity is increased by the binary recording and ternary recording. |
