Multistage storage CD read and write system based on phase changing material

Abstract

The invention relates to a reading / wriing system for multi-stage optical storage disc. It includes writing light path along longitudinal direction, reading path along transverse direction, a set for detecting phase directly located above spectroscope, and multi-stages optical disc. The writing light path is from writing laser, collimating lens, spectroscope to converging lens. The reading light path is from reading laser, collimating lens, spectroscope, WoIastoh prism, to spectroscope and converging lens in the writing light path. The writing and reading lasers are located on the flocal pointof relevant spectroscopes. The direct phase detecting set consists of spectroscope, then in I optical path: 1 / 4 wae plate, half-wave plate, polarized spectroscope; and in II optical path; middle density filter of reflector, half-wave plate, polarized spectroscope. The end of optical path is a photoelectric detector that receives a beams of light. The invented system provides capacities to realizehigh density of storage and high data transferring rate with simple structure.

Description

technical field [0001] A phase-change material-based multi-level storage optical disc read-write system belongs to the technical field of optical storage. Background technique [0002] In various existing optical storage systems, devices that read the changes in reflected light intensity to read stored data information are used. For example, a single-beam serial read-write device is used in Digital Versatile Disc-DVD. , see figure 1 The optical path diagram shown: the laser 1 emits a single-wavelength beam that is parallelized by the collimator lens 2, and shoots to the polarizing beam splitter 3, and then shoots to the condenser lens (that is, the objective lens 5) through the 1 / 4 wave plate 4, and focuses the beam on the reading surface of the optical disc 6. written on the face. The reflected light beam on the reading and writing surface returns along the original path through the objective lens 5, and the 1 / 4 wave plate 4 is directed to the polarizing beam splitter 3, ...

AI Technical Summary

Problems solved by technology

It has the following disadvantages: (1) data is serially written and read by a single beam, and its reading and writing speed is difficult to increase; (2) reading is based on light intensity modulation, which is easily affected by disk surface defects or laser modulation errors Its sensitivity is difficult to adapt to the requirements of short-wavelength, large numerical aperture and multi-level storage for future optical disc storage; (3) At present, because each recording layer of the disc uses different transmittance and reflectance ratios, it has a great influence on the returned light intensity Large, in order to ensure that sufficient readout signals can be obtained, the recording stack is generally only two layers, so it is difficult to increase the storage dimension, and its storage capacity is also difficult to increase

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