KR20100010754A - An optical disk - Google Patents

Abstract

PURPOSE: An optical disc is provided to prevent the partial loss and distortion of information by including a protection layer. CONSTITUTION: A substrate(210) comprises a burst cutting area and a data area. A reflective layer(220) is located on the substrate. A cover layer(240) is located on the reflective layer. A protective layer(230) is formed between the reflective layer and the cover layer. A record layer is formed between the reflective layer and the protective layer.

Description

An optical disk

The present invention relates to an optical disc, and more particularly, to an optical disc capable of forming a protective layer to prevent partial loss and distortion of information.

With the advent of the multimedia era comprehensively dealing with video signals, audio signals and computer data information including moving pictures and still pictures, package media such as various discs including CDs, DVDs and BDs have been widely spread.

In recent years, attempts have been actively made to apply optical discs as recording media for mobile phones, digital cameras, broadcasting and movies.

This trend is likely to stand out in the next generation of media. In the next generation media, the size of the recording mark is getting smaller as the laser wavelength is shorter and the numerical aperture is larger for higher transmission speed and higher storage capacity.

Optical discs are largely read-only (ROM), recordable (R) capable of recording information only once, and rewritable (RE) capable of repeatedly writing, reading, and erasing information. ) There is a disk.

In general, an optical disc inserts a code into a burst cutting area (BCA) by irradiating a laser to a reflective layer or a recording layer positioned on a cover layer. Disc information, copy protection code, and the like can be recorded in the BCA code.

In the case of optical discs, as with conventional CDs and DVDs, the information formed by the reaction between the dielectric layer and the reflective layer is damaged, and thus may be subjected to strong external environmental stimuli such as shortening the life of the information storage or being left in a high temperature or high humidity for a long time. In this case, there is a disadvantage in that the reliability of information storage is lost due to partial loss or distortion of information.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical disc in which a protective layer is formed on the optical disc to prevent partial loss and distortion of information, thereby increasing the reliability of information storage.

An optical disk according to the present invention for achieving the above object includes a substrate including a burst cutting region and a data region, a reflective layer located on the substrate, and a cover layer located on the reflective layer, and between the reflective layer and the cover layer Further includes a protective layer.

According to the present invention, a protective layer is formed between the cover layer and the recording layer to prevent partial loss and distortion of the information recorded on the optical disc so that the information is not compromised and reliability of the information stored on the optical disc can be improved. There is an advantage.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

1 is a plan view of an optical disk according to the present invention.

Referring to FIG. 1, the optical disc 100 may be a recordable Blu-ray disc or a playback-only Blu-ray disc, but is not limited thereto. That is, optical discs such as CDs and DVDs may also fall within the scope of the present invention.

When proceeding from the clamping hole on the innermost inner circumferential surface of the optical disk 100 to the outer circumferential surface, looking at each region, the clamping area (110), burst cutting area (BCA, 120, a lead-in area 130, a data area 140, and a lead-out area 150 may be included.

Although there is a transition area between the clamping area 110 and the burst cutting area 120, it is noted that it is not shown.

When the burst cutting area 120 is seated in the optical disc reproducing apparatus, the optical disc apparatus is first accessed. The burst cutting area 120 is provided with the BCA code 125 and the like, such as a disc serial number or encryption information for disc copy protection. Various disc main information can be recorded.

The burst cutting region 120 may be located between 21.3 (+0.0, -0.3) and 22.0 (+0.2, -0.0) mm starting from the inner circumferential surface of the optical disk 100. In addition, the data area may be located between 22.0 (+0.2, -0.0) and 60 mm.

2 to 7 are cross-sectional views showing various embodiments of the optical disk according to the present invention. 2 to 7 schematically show the cross-sectional view taken along the line II 'of FIG.

Referring to FIG. 2, an optical disk 200 according to the present invention includes a substrate 210, a reflective layer 220, a guarded layer 230, a cover layer 240, and a coating layer. (coating layer, 250).

The optical disc 200 according to FIG. 2 may be a BD-ROM SL (Blu-ray disc-ROM Single Layer).

The substrate 210 may be made of polycarbonate, but is not limited thereto. One surface of the substrate 210 may be formed of a regularly patterned protrusion and a groove. In addition, when the optical disc 200 is a BD-ROM, the information to be reproduced may already be stored on the substrate.

The reflective layer 220 may be positioned on the substrate 210. The reflective layer 220 may adjust the balance of the absorption and reflection of the laser, the absorption, transmission and emission of the laser by adjusting the multiple reflection conditions.

The cover layer 240 and the coating layer 250 may be positioned on the reflective layer 220. In the current Blu-ray Disk (BD), there are two methods of forming the cover layer 240.

A method of forming a cover layer by irradiating UV-curable photocurable resin and a method of attaching polycarbonate (PC sheet) using PSA (pressure sensitive adhesive) are used.

However, although the thickness of the cover layer 240 is 95 to 105 ㎛ thin, but a high-density, large capacity BD requires a stable material and structure.

In addition, the coating layer 250 may be a hard coating layer that is coated with a UV resin on the cover layer 240.

The protective layer 230 may be positioned between the reflective layer 220 and the cover layer 240. The protective layer 240 may damage the information formed due to the reaction between the reflective layer 220 and the cover layer 240, thereby shortening the lifespan of the information storage or strong external environmental stimuli such as high temperature and high humidity. It is possible to prevent the loss of reliability of information storage due to inadvertent loss or distortion of information due to long-term neglect in one environment.

The protective layer 230 may be made of Au, Si, Sb, Te, Ge, Al, Cu, Pb, Nb, Ni, Ag, or an alloy thereof. More preferably, Au and Si, Sb, Te, Ge, Al, Cu, Pb, Nb, Ni and Ag may be formed of an alloy to which at least one element is added.

Au alloy is more stable than Ag alloy, which is a conventional reflective film material, and Au alloy is characterized by no discoloration, corrosion and rust, and is chemically stable and can be used in places where long-term data needs to be preserved.

In addition, in the case of the protective layer 230, a material having a low reflectance is good, and in particular, in the case of Au, stacking is possible from 2 nm to 10 nm, but a low reflectance and high corrosion resistance at a general Blu-ray wavelength may exhibit good characteristics. In order to minimize the diffraction effect of the multilayer barrier, the thickness may be 2 nm to 3 nm.

In the case of the protective layer 230, a ratio of at least one of Au and Si, Sb, Te, Ge, Al, Cu, Pb, Nb, Ni, and Ag is preferably 1: 1 to 1:99. The protective layer 230 may be formed.

When the ratio of at least one of Au, Si, Sb, Te, Ge, Al, Cu, Pb, Nb, Ni, and Ag is outside the ratio of 1: 1 to 1:99, the corrosiveness becomes high and the The reflectance becomes high.

Referring to FIG. 3, the optical disk 300 according to the present invention includes a substrate 320, a reflective layer 330, a protective layer 340, a space layer 350, a second reflective layer 360, and a second protective layer. The layer 370, the cover layer 380, and the coating layer 390 may be formed.

3 may be a BD-ROM Blu-ray Disc-ROM Dual Layer (DL-ROM).

Since the optical disc 300 according to the present invention is similar to the optical disc 200 of FIG. 2 and the material forming the stacked structure and its components, only the difference will be described.

The reflective layer 330 may be positioned on the substrate 320, and the protective layer 340 may be positioned on the reflective layer 330.

In the BD-ROM DL, a space layer 350, which functions as the substrate 320, may be formed on the protective layer 340. Information to be reproduced may be stored on the space layer 350.

The second reflective layer 360 may be positioned on the space layer 350, and the second protective layer 370 may be positioned on the second reflective layer 360. The second reflective layer 360 and the second protective layer 370 are the same as the reflective layer and the protective layer of FIG. 2 and are omitted. The cover layer 270 and the coating layer 380 may be positioned on the second protective layer 370.

In addition, although the optical disk 300 shown in the figure is composed of two stacked structures, it may be applied to two or more identical stacked structures.

Referring to FIG. 4, the optical disk 400 according to the present invention includes a substrate 410, a reflective layer 420, a dielectric layer 430, 450, a recording layer 440, a protective layer 460, The cover layer 470 and the coating layer 480 may be formed.

The optical disc 400 according to FIG. 4 may be a BD-R SL (Blu-ray disc-Recordable Single Layer).

Since the optical disc 400 according to the present invention is similar to the optical disc 200 of FIG. 2 and the materials forming the stacked structure and components thereof, only the differences will be described.

The recording layer 440 may be positioned on the reflective layer 440. The recording layer 440 may be formed of a single layer or may be formed of more than two layers. In the drawings, a case in which a single layer is formed is illustrated.

The materials constituting the recording layer 440 are mainly made of a material that absorbs light, and the absorbed light energy is converted into thermal energy to generate heat, and may cause a reaction to express optical contrast.

The recording layer 440 includes the first recording layer 440, silver (Ag), antimony (Sb), at least one selected from the group consisting of silicon (Si), germanium (Ge), or antimony (Sb). The second recording layer 130 may include at least one selected from the group consisting of bismuth (Bi), tellurium (Te), copper (Cu), aluminum (Al), and titanium (Ti).

In addition, the recording layer 440 may be formed of an organic material such as a dye.

In the recording layer 440, desired contrast can be obtained by easily adjusting the multi-reflection conditions through laser light having a wavelength of 405 nm and a numerical aperture of 0.8 to 1.0.

The dielectric layers 430 and 450 may be located between the reflective layer 420 and the recording layer 440 and between the recording layer 440 and the protective layer 460, and may be used as a material for the functions of the optical disc 400 and other components. It may be removed depending on characteristics and the like.

The dielectric layers 430 and 450 generally use materials having a high optical refractive index. The desired contrast can be obtained by easily adjusting the multi-reflection conditions through the thickness adjustment of the dielectric layers 430 and 450.

The dielectric layer 430 positioned between the reflective layer 420 and the recording layer 440 may control the recording power and the shape of the recorded mark by controlling the rate at which heat is emitted from the recording layer to the reflective layer 420.

In addition, the dielectric layer 450 positioned between the recording layer 440 and the protective layer 460 may prevent the plastic from being damaged by the high temperature.

The dielectric layers 430 and 450 may also be made of ZnS-SiO ₂ (ZSSO) or TiO ₂ , but are not limited thereto.

In addition, the protective layer 460 may prevent the formed information from being damaged due to the reaction between the dielectric layer 430 and the reflective layer 420.

Referring to FIG. 5, the optical disc 500 according to the present invention may be a BD-R DL (Blu-ray disc-Recordable Dual Layer).

The optical disk 500 according to the present invention includes a substrate 505, a reflective layer 510, a dielectric layer 515 and 525, a recording layer 520, a protective layer 530, a space layer 535, and a second reflective layer 540. The second dielectric layers 545 and 555, the second recording layer 550, the second protective layer 560, the cover layer 565, and the coating layer 570 may be formed.

In addition, although the optical disk 500 shown in the figure is composed of two stacked structures, two or more identical stacked structures may be formed.

Since the optical disc 500 according to the present invention has a similar material to the components of the stacked structure of the optical disc 400 of FIG. 4, the description thereof will be omitted below.

Referring to FIG. 6, the optical disk 600 according to the present invention may be a Blu-ray disk-rewritable single layer (BD-RE SL).

The optical disc 600 according to the present invention includes a substrate 610, a reflective layer 615, dielectric layers 620 and 640, an interface layer 625 and 635, a recording layer 630, a protective layer 645, and a cover layer 650. ) And the coating layer 655.

The optical disk 600 according to the present invention will be omitted below with the optical disk 400 of FIG. 4 and only the differences will be described.

Referring to the drawing, the interface layers 625 and 635 may be located on at least one of the top and bottom surfaces of the recording layer 630. The interface layers 625 and 635 are used only for Rewritable (RE) discs.

When recording the information on the recording layer 630 of the optical disc 600, the interface layers 625 and 635 can increase the number of repetitive recordings by increasing the heat transfer rate, and act as crystallization promoters to improve crystallization characteristics. It is possible to improve the erasing characteristics of the repeatable recording disc.

In addition, a dielectric layer 620 may be formed between the reflective layer 615 and the interface layer 625, and a dielectric layer 640 may also be formed between the interface layer 635 and the protective layer 645.

Like the recording layer of FIG. 4 described above, the materials constituting the recording layer 630 are mainly made of a material that absorbs light, and the absorbed light energy is converted into thermal energy to generate heat, and also generates a reaction to optically. Contrast can be expressed.

The recording layer 630 of the rewritable (RE) optical disc 600 is composed of a single layer unlike the recording layer of the recordable (R) optical disc of FIGS. 4 and 5 described above.

The recording layer 630 is determined, either an amorphous state is stable at the same time, both the possible high-speed phase transition of between ₇₀ Sb ₃₀ Te state The thin film which consists of MSbTe alloy whose main component is a SbTe alloy near a process point is preferable. Where M is In, Ga, Zn, Ge, Sn, Si, Cu, Au, Ag, Pd, Pt, Pb, Cr, Co, O, N, S, Se, Ta, Nb, V, Bi, Wr, It may be at least one of Ti, Mn, Mo, Rh and rare earth elements.

The dielectric layers 620 and 640 are similar to those of the dielectric layer described above with reference to FIG. 4, and may be formed or removed depending on the function of the optical disc 600 and the characteristics of the material between the other components.

Referring to FIG. 7, the optical disk 700 according to the present invention may be a Blu-ray disk-Rewritable Dual Layer (BD-RE DL).

The optical disc 700 according to the present invention includes a substrate 705, a reflective layer 710, a dielectric layer 715 and 735, an interface layer 720 and 730, a recording layer 725, a protective layer 740, and a space layer 745. A second reflective layer 750, a second dielectric layer 755, 775, a second interface layer 760, 770, a second recording layer 765, a second protective layer 780, a cover layer 785, and a coating layer. 790.

In addition, although the optical disk 700 shown in the drawing is composed of two stacked structures, it may be applied to two or more identical stacked structures.

Since the optical disc 700 according to the present invention has a similar material to the components of the stacked structure of the optical disc 600 of FIG. 6, the description thereof will be omitted below.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the specific embodiments described above, but the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

1 is a plan view of an optical disk according to the present invention, and

2 to 7 are cross-sectional views illustrating various embodiments of an optical disk according to a temporary embodiment of the present invention.

<Explanation of symbols on main parts of the drawings>

200: optical disk 210: substrate

220: reflective layer 230: protective layer

240: cover layer 250: coating layer

Claims (13)

A substrate including a burst cutting region and a data region; A reflective layer on the substrate; And A cover layer disposed on the reflective layer; And a protective layer between the reflective layer and the cover layer. The method of claim 1, And at least one stacked structure including a space layer, a second reflective layer, and a second protective layer on the protective layer. The method of claim 1, And a recording layer between the reflective layer and the protective layer. The method of claim 3, And at least one of an upper surface and a lower surface of the recording layer. The method of claim 3, And at least one stacked structure including a space layer, a second reflective layer, a second recording layer, and a second protective layer on the protective layer. The method of claim 5, And a second dielectric layer on at least one of an upper surface and a lower surface of the second recording layer. The method of claim 1, And a recording layer, and an interface layer on at least one of upper and lower surfaces of the recording layer, between the reflective layer and the protective layer. The method of claim 7, wherein And a dielectric layer between at least one of the reflective layer and the interface layer and between the interface layer and the protective layer. The method of claim 7, wherein A stacked structure including a space layer on the protective layer, a second reflective layer, a second recording layer, and a second interface layer and a second protective layer on at least one of an upper surface and a lower surface of the second recording layer are provided. And at least one further optical disc. The method of claim 9, And a second dielectric layer between at least one of the second reflective layer and the second interface layer and between the second interface layer and the second protective layer. The method of claim 1, The protective layer is an optical disc, characterized in that the metal compound containing Au. The method of claim 11, The metal compound is at least one element from the group consisting of Au and Si, Sb, Te, Ge, Al, Cu, Pb, Nb, Ni and Ag. The method of claim 1, And a coating layer on the cover layer.

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