Optical information recording medium and method for manufacturing the same

Abstract

An optical information recording medium having a recording layer whereupon information of a large quantity can be recorded is manufactured by a simple system. Two light transmitting substrates whereupon a first photosensitive polymer and a second photosensitive polymer are developed, respectively, are bonded to each other on the photosensitive polymer layers to form one recording layer. Since the recording layer has a larger optical absorptance as the optical focal point for information recording moves deeper in the depth direction, information can be recorded without reducing information record transfer rate.

Description

technical field [0001] The present invention relates to an optical information recording medium and a method for manufacturing the same. Specifically, the present invention relates to a technique related to an optical information recording medium to be manufactured such that the absorptivity of light used for information recording is proportional to the depth of the position in the recording layer from the incident side. Increase. Background technique [0002] Examples of optical discs used as optical information recording media include compact discs (CDs), digital versatile discs (DVDs), and Blu-ray Discs (BD) (registered trademark) and the like. The recording density of these optical discs is gradually increasing. In recent years, with an increase in the amount of information, optical information recording media capable of recording a large amount of information are required. [0003] Volumetric recording (in which information is recorded in the depth direction of the r...

AI Technical Summary

Problems solved by technology

[0004] However, for example, in the case of a multi-layer optical disk, although it is very important to accurately overlap the recording layer made of resin (in which signal pits are formed by transfer by a metal stamper) and the reflective film, these steps are extremely complicated, and Due to low production capacity, serious cost increases are inevitable

[0005] In addition, in the case of bulk recording using two-photon absorption, the overall cost of the system increases because development of a high-stability recording medium and a high-power laser such as a femtosecond laser are required

[0006] In addition, in the case of volume holographic recording, the reduction of the S / N ratio due to the increase of medium noise caused by multiplexing recording, the difficulty of handling the photosensitive polymer medium, and the impact on the space with multiple pixels Factors such as the demand for modulators and image sensors increase the overall cost of the system

[0007] As described above, all these capacity recording methods have drawbacks in practical use because the system for manufacturing the optical information recording medium is complicated and the cost of the system as a whole increases.

Images