Optical recording medium

A technology of optical recording medium and recording film, which is applied in the direction of optical recording carrier, optical recording system, data recording, etc., can solve the problems of insufficient research on groove side wall optimization, steepness, slope of groove side wall, etc., and achieve excellent Reproduction characteristics, effects of high reproduction output

Inactive Publication Date: 2003-12-31
SONY GRP CORP
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, when such a fine track pitch as set in the above-mentioned DVR is narrow and small, the patterned exposure of the above-mentioned light causes the sidewall of the groove to be slightly inclined
[0013] Thus, although attempts have been made to pattern photoresists, such as by electron beam lithography, by reducing the beam spot size by placing focusing lenses near the exposure surface in the optical system, i.e. by adopting a so-called near-field configuration, method of exposure in order to make the trench sidewall steeper, or to improve the situation, however research on the optimization of the trench sidewall is insufficient, and sufficient reproduction output has not been achieved

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Optical recording medium
  • Optical recording medium
  • Optical recording medium

Examples

Experimental program
Comparison scheme
Effect test

no. 1 example

[0071] In this embodiment, the concave portion 2 is a groove arranged as a tracking guide groove, the size of which is 100 nm deep, 0.12 μm wide, and the interval between the grooves is 0.6 μm, and the slope of the side wall of the groove is tanθ =2, as shown in Figure 3.

[0072] Also, in this embodiment, a phase modulation type optical disc is produced using a polycarbonate (PC) substrate 1 in which a depressed portion 2, i.e., a groove, is formed on one main surface of the substrate 1, and a metal film 3 was formed by sputtering Ag to a thickness of 20 nm on the groove-forming surface, and a recording film 4 of an organic pigment film, a dielectric film 5 formed of SiN with a thickness of 10 nm, and a light-transmitting protective film 6 were sequentially formed on the metal film 3.

[0073] Organic pigment films are formed by spin coating. In this case, the thickness of the film was set to be 170 nm inside the groove and 70 nm at the land portion.

[0074] In addition, i...

no. 2 example

[0084]FIG. 8 shows the measurement results of the corresponding reproduced signal amplitude, that is, the amount of returning light obtained by changing the groove width in the optical recording medium according to the first embodiment. As shown in FIG. 8, the signal amplitude decreases when the groove width exceeds a certain value. The reason for this is that when the groove width is thus increased compared to the mark width, the ratio of the mark width within the reproducing spot increases as the reproducing spot approaches the center of the mark, and the reflectance due to the difference with the land portion Interference is reduced and increased.

[0085] Specifically, FIG. 9 shows reproduced signal levels in the groove length direction when the groove width is increased to 0.28 µm. According to FIG. 9, the reflectance increases near the center of the mark.

[0086] According to FIG. 8 , it can be understood that the best results can be obtained when the groove width is ...

no. 3 example

[0093] In the third embodiment, similarly to the first embodiment, a phase modulation type optical disc is manufactured by using a substrate 1 utilizing polycarbonate (PC), in which grooves are formed as depressed portions 2, and side walls are substantially vertical The metal film 3 is formed by sputtering 20nm thick Ag on the surface where the groove is formed, and then a recording film 4 formed of an organic pigment film, a dielectric film 5 formed of 10nm thick SiN, and an optical film are deposited thereon. Transmission protective film 6.

[0094] Regarding the width of the groove of the recessed portion 2 in the substrate, in order to obtain the above-mentioned excellent effect, in this embodiment, the width of the recessed portion 2, that is, the width of the groove is set to 0.14 μm. In addition, the width of the land is set to be the same as the width of the groove. N.A. of the objective lens = 0.85.

[0095] Furthermore, in this embodiment, an optical disk is manuf...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
wavelengthaaaaaaaaaa
reflectivityaaaaaaaaaa
reflectivityaaaaaaaaaa
Login to view more

Abstract

A phase-modulation type optical recording medium comprising at least one layer of recording film (4) and at least one layer of metal film (3) on a recesses-formed substrate (1), wherein at least one layer of constituent film constituting the recording film consists of an organic matter that absorbs and breaks down a laser beam to have its refractive index changed, and the width of a recess (2) is 0.10 [mu]m-0.21 [mu]m, whereby providing a WORM type, high-density-recording optical recording medium capable of producing a high reproducing output.

Description

technical field [0001] The present invention relates to an optical recording medium, especially a phase modulation type optical recording medium having excellent reproduction output characteristics, wherein the reproduction of the recording portion is carried out by irradiating light with a wavelength λ in the range of 380nm to 450nm, and Organic pigment materials are used as recording films. Background technique [0002] Hitherto, functional organic pigment materials have been widely used as recording materials for write-once optical discs, and are mass-produced at low cost, especially as write-once compact discs (CD-R). [0003] Also, in the optical system of DVD (Digital Versatile Disc), the write-once type has been standardized as the write-once type DVD-R, and has been put on the market. [0004] In addition, as the so-called next-generation optical disc recording medium, which means higher recording capacity, that is, higher recording density, it has been considered t...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B32B3/02G11B7/0045G11B7/005G11B7/007
CPCG11B7/00451G11B7/24079G11B2007/25713G11B7/259G11B7/2534G11B7/2472G11B2007/2571Y10T428/21G11B7/246
Inventor 佐飞裕一
Owner SONY GRP CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products