G11B2007/13727

OPTICAL DISK, METHOD OF MANUFACTURING SAME, OPTICAL INFORMATION DEVICE, AND INFORMATION PROCESSING METHOD
20210327466 · 2021-10-21 ·

Provided is a method of manufacturing an optical disk having at least a cover layer, a first information recording surface, a first intermediate layer, a second information recording surface, a second intermediate layer, and a third information recording surface in order from a surface irradiated with a light beam on at least one side, wherein a numerical aperture of an objective lens that converges the light beam on any of the recording surface of the optical disk when information recording or information reproduction of the optical disk is performed is 0.91, standard value dk of each thickness from the surface to the first to third information recording surfaces is set on the premise of standard refractive index no, where k is 1, 2, 3, and a target value of each actual thickness from the surface to the first to third information recording surfaces is determined by a product of conversion coefficient g(n) depending on refractive index n from the first to third information recording surfaces, and standard value dk.

Method for reading and writing with holographic system and holographic storage system

A method for reading and writing with holographic system includes the following operations: (a) providing a reference light and a signal light; (b) transferring the reference light and the signal light to an optical recording medium, for recording an interference grating; (c) changing the reference light and the signal light and repeating the operations (a) to (b) until M interference gratings are recorded on the optical recording medium; (d) providing a reading light to the optical recording medium, for reading the M interference gratings at the same time to generate an interference result, wherein the interference result is a result that diffraction signals of the M interference gratings interfere to each other; and (e) changing the reading light and repeating the operation (d), for obtaining N interference results. A holographic storage system is also disclosed herein.

Holographic data storage system
09620164 · 2017-04-11 · ·

Provided is a holographic data storage system characterized by including: a first polarizing beam splitter (PBS), wherein at least either of a first lens module and a second lens module transmits P-polarized light and reflects S-polarized light; a relay lens collecting light passing through the first PBS; a mirror reflecting the light collected through the relay lens back to the relay lens; and a quarter wave plate located between a second PBS beam splitter and the relay lens, converting transmitted linearly polarized light into circularly polarized light, and converting the circularly polarized light into linearly polarized light. By reducing the volume of the relay lens, it is possible to decrease the size of the holographic data storage system, and by decreasing the number of lenses, it is possible to lower manufacturing costs.