CN101064129A - Rewritable data storage medium - Google Patents

Abstract

The rewritable data storage medium (1) has a rewritable recording layer (9) provided with a tracking structure (8). Said layer (9) has a data recording area (5). An erasable identification mark is present in an identification mark area (4, 4') other than the data recording area (5). The data recording area (5) has a first tracking structure (8'), whereas the identification mark area (4, 4') is substantially free from a tracking structure or has a second tracking structure (8'') substantially different from the first tracking structure (8'). Thus erasure of the identification mark is practically impossible, because the location of the erasing spot of a recorder cannot be controlled precisely in radial direction.

Description

Rewritable data storage medium

The application is that application number is dividing an application of 01800277.3 original bill application, and the applying date of this original bill application is February 9 calendar year 2001, is 00200613.8 in first to file, and priority date is on February 23rd, 2000.

Technical field

The present invention relates to a kind of rewritable data storage medium, but it has the regenerative recording layer that is provided with the tracking structure with track, described layer has data recording area, with can wipe identification marking, it is present in extension above several tracks radially wide of the identification marking zone that is different from data recording area and its track structure in data recording area.

Background technology

Described rewritable data storage medium from Japanese patent application JP-09073666-A as can be known.Known medium is a kind of optical recording media.The optical readable pattern is written in the outside of the data recording area of recording layer.This pattern with the naked eye or by machine can read, and can be used as identification marking.

But but overwriting data storage and special regenerative recording on optical recording media are found in the high density storage of using more and more at Large Volume Data current.In optical recording media, the reciprocation of radiation laser beam and optical recording media by for example focussed laser beam, information is reproduced.Recently one type the optical storage media that occurs has and after the manufacturing information is being recorded in ability on the medium.In addition, stored subsequently information can be wiped free of or revise.In dish embodiment, such optical storage media is commonly called can wipe maybe and can rewrites optical memory disc.For example can rewrite CD (RW), DVD-RW, DVD+RW, random access memory DVD (RAM), and the red indigo plant of digital video record (DVR) (red and blue) dish, the wherein red and blue wavelength that refers to radiation laser beam for example writes down and reads laser beam.

The rewritable optical recording dish has the recording layer that the radiation with relative high power levels is played response.This radiation that applies has changed the characteristic of recording layer.Being detected by light alternately of the radiation laser beam of these characteristic changings by relative low-power level, and the data that are encoded by characteristic changing can be reproduced.For example the intensity of folded light beam or polarization variations can be detected and be converted into electric signal by photodiode.This electric signal is converted into the form that can be handled by signal processing system expediently subsequently.

In order to provide copy protection safety to the data that are stored on the storage medium, found out technical needs, be used to provide a kind of optical storage media with identification marking.This identification marking is applied in each piece of the storage medium of CD for example.This identification marking can for example be the bar code of expression one sequence number.During the reproducting content of record protection, the data utilization is encrypted based on the key of this identification marking.Prevented the clone that so-called position is duplicated or coiled like this.Example is the copy protection that is used for recordable media (CPRM) DVD-RAM and possible DVD-RW.During duplicating the encrypted content that is present in the data recording area, the identification marking of master is not copied to destination media.This empty destination media has another kind of identification marking, and it has been applied to it during fabrication.Because decruption key must be based on the identification marking of clone's dish, this clone's dish does not belong to the correct identification marking that is replicated content, reads the player of this medium of being cloned and can not construct correct primitive solution decryption key.In order to place the identification marking of correct premaster, the computer hacker at first must wipe the identification marking of blank panel, writes the identification marking corresponding to enciphered data subsequently.

In manufacture process,, a kind of important requirement of identification marking can be applied in record/rewritable media at low cost but being identification marking.As for DVD-ROM, a kind of possibility is, pass through YAG laser in so-called pulse cutting zone (BCA) (Burst Cutting Area), carry out to wipe for example ablation record of " bar code " type mark of identification marking from radius 22.3 to 23.5mm.Because its cost and owing to utilizing this laser ablation record that the danger of pollution is arranged, this laser is used hardly.Alternatively narrow pulses cutting zone (NBCA) (Narrow Burst Cutting Area), it is for CD-RW, DVD-RW, DVD+RW, DVD-RAM and red or blue DVR are feasible.Compare with the identification marking of can not wiping in BCA, for writing the identification marking that can wipe, this NBCA has covered narrow region, for example from radius 22.7 to 23.5mm.The phase change recording layers that is used for these media can be coated by hydatogenesis or sputter.Like this Chen Ji recording layer be amorphism and show low reflection.In order to obtain the suitable recording layer of high reflection, the data recording area of this layer must be at first by crystallization fully, and it is commonly called initialization, and it occurs in the final stage of producing each medium.This is to carry out in being called as the production equipment of initializer, and wherein the recording layer that moves of laser beam flying and heating is to the temperature of fusion that is lower than it but be higher than the temperature of the recrystallization temperature of the unsetting recording layer crystallization of impelling of it.This production equipment crystallization has the path of certain radial width of a lot of tracks of tracking structure.Whole data recording area must be by crystallization, and it is to finish by move the initialization light beam at radial direction in rotating media.Yet in the inside and outside zone of dish, for example in the inside of the 23.5mm of DVD+RW radius with in the outside of 58.5mm radius, this dish can be by using partly crystallization of initialized pulse laser beam quilt.So identification marking, for example bar code pattern can be written in the outside of data recording area.By beginning to the pulse sequence of the spin locking of CD with Constant Angular Velocity (CAV) mode rotating disc, identification marking is written on the dish.Because identification marking is recorded and has only increased time of few percent for this process steps during initialization, production cost is very little.Identification marking is erasable, is recorded because of the identical or opposite characteristic change of its service recorder layer, as it is used to data recording.

Disk in 23.5mm and surpass the optical characteristics of layer of 58.5mm and consistance poor than data recorded area usually.Therefore, in order to have reliable detection, preferably use the low-density pattern.

Usually the initialization laser beam be rectangle and to measure in tangential direction approximately be 1 micron and radially be 100 microns.The record that writes identification marking for DVD-RW and DVD+RW is proved.Owing to write identification marking is the part of the initialization step that required, and it is a kind of attractive and economic method.

In the rewritable optical recording medium as the inversion of phases described in the above, according to described Japanese publication, identification marking is written into during initialization.

The shortcoming of the known media of describing in described application is that consumer's optical disc recorder can relatively easily be wiped identification marking.This register comprises writes laser, and it can be used for wiping, and rewrites or the change identification marking.But identification marking is recorded in the zone that the register access that utilizes the consumer reads.By the firmware of change controlling recording device driving with by locating laser record/read head, identification marking can be wiped free of by the accurate position that record/read head is moved to identification marking, and the another kind of identification marking of content that belongs to the bootlegging of source tray can be recorded.The computer hacker can walk around the function of the copy protection of identification marking in this way.

Summary of the invention

An object of the present invention is to provide a kind of data storage medium of describing in the beginning paragraph, wherein by being suitable for record on data storage medium, the subscriber equipment that rewrites and read is suppressed wiping of identification marking.

This purpose realizes by the data recording area with first tracking structure, and the identification marking essentially no tracking structure in zone or have second tracking structure that is different from first tracking structure fully.Owing to lack in the identification marking zone or revised second tracking structure, utilize user writer to wipe identification marking and be suppressed, and the tracking of laser head is with to wipe action normally impossible with mode identical in data recording area several tracks are as one man carried out.Identification marking usually at radial direction across certain distance, it is corresponding to a hundreds of track of the tracking structure in data recorded area.In this application, anything of from several to hundreds of scope may be represented in word " several ".

In preferred embodiment, the essentially no tracking structure in identification marking zone.This tracking structure perhaps is used for " guiding " any other device of write head during writing down, and is very shallow or or even lacks.The tracking structure of data recording area can partly be present in for example identification marking zone of proximity data posting field, and stops suddenly when for example radially moving inward.This is very perfect and easily realizes the embodiment of the medium according to the present invention.User writer usually can not the Tracking Recognition marked region, so consistent writing or wipe almost is impossible.Because user writer is write luminous point and typically had about 0.5 to 1 micron diameter it can not wipe identification marking, it can be that 0.8mm is wide at the radial direction of single rotating disk for example.When radial direction moves laser head, register must as one man be wiped hundreds of commentaries on classics.Because the essentially no tracking structure in identification marking zone, the laser head in the register only relatively the CD rotation about a few.Owing to always allow the fact devious between CD and bare headed detent mechanism, identification marking can not or almost can not fully and as one man be wiped/rewrite to laser spots.Because only moved approximately a few, in order to tackle these tolerances, but the width of described mark must be across whole usage space, for example the 0.8mm in the radial direction in identification marking zone during reading identification marking.During reading identification marking, because player is placed on middle precalculated position, identification marking zone roughly to its read head, and one week of rotating disc meanwhile, but reading variation or any other detected characteristics of reflectivity, is not problem so lack tracking structure in the identification marking zone.When reading a curve that has moved and depart from circular ideal, off-centre operation for example, because identification marking can have the spatial frequency lower than user data, hundreds of position only in single commentaries on classics for example is not so have problems.

In another embodiment, second tracking structure comprises the track of at least one spiral groove shape, and it is interrupted at least one position.When this spiral of identification marking zone is interrupted, the read/write head will " be lost " tracking, and as one man to wipe or write down identification marking almost be impossible.Preferably this spiral is interrupted in several places, impels laser head usually " to lose " tracking.By interrupting being used in the laser of making in the tracking structure in the same manner, this improved tracking structure can relatively easily obtain.

In another embodiment, second tracking structure comprises the track of a plurality of concentric grooves shapes.When using concentric grooves to replace spiral, laser beam remains in the concentric grooves during following the tracks of.Because concentric grooves is closed oneself, the position that produces the laser head of laser beam when following the tracks of does not change at the radial direction of relative CD.The user writer driver to the identification marking zone wipe or write write laser beam along with groove returns itself, extraordinary image is the stylus of the real end of 45rpm vinyl disc in the past.Because this concentric grooves, user's optical disc recorder for example can not be wiped across the identification marking of a hundreds of track at least.The part identification marking of wiping a top concentric grooves is possible, but the remainder identification marking on the contiguous concentric grooves remains complete.The user is difficulty very, perhaps may be positioned at laser beam in each concentric grooves that comprises the part identification marking hardly.When the essentially no tracking structure in identification marking zone, carry out reading of identification marking as mentioned above.Yet during reading identification marking, it can be favourable that read head is placed on tracing mode.The radial width of identification marking may be littler as a result, for example tens tracks only.So suppose during the manufacturing dish, to write this narrower identification marking, write the dedicated head of this identification marking simultaneously and in several concentric grooves, follow the tracks of subsequently.This needs special-purpose tracking servo, and it is unavailable in user writer.

The combination that much has and do not have the zone of tracking structure is possible.Even have be used in data recording area in the zone of identical track may reside in the identification marking zone.Particularly the zone of proximity data posting field can still comprise be used in data recording area in some identical tracks.Even may utilize all embodiment that describe in this application to change the external radius place that identification marking is write on the rewritable data storage medium in the data recording area outside.

In improving embodiment, at least one track of second tracking structure utilizes address information modulated.This address information can be the radial location number that is encoded, track number or other reference signal.The example of coded address information is phase place or the warbled track wobble and relative short interruption groove that utilizes the hole header to carry out in tracking structure.The latter does not make laser head lose tracking.The advantage of this address information is that the read/write head of production equipment can be determined its exact position in the media by reading address information, and at the production period according to data storage medium of the present invention, writing of identification marking can be performed in the position of clearly determining.Hardware and software special-purpose in production equipment can make identification marking write in the improved tracking structure, the spiral groove that for example has the concentric of address information or interrupt.Relatively the whole production time of medium, the extra production time is relatively low.For example writing 20 track identification markings when typical 25Hz rotational speed need be more than 1 second time.Specialized hardware and the software pointed out emphatically in production equipment are unavailable in user writer, therefore can not wipe or write identification marking.

Recording layer generally includes the material that can change between amorphous state and crystalline state, and the recorded information in recording layer normally can light reads.At present, it being more widely used in the rewritable optical recording technology.

In an embodiment, recording layer comprises the magnetic material that can change between first and second magnetized states.It is readable by magnetic and/or light to be recorded information in recording layer.Utilize to suspend near the Magnetic reading head above described magnetic recording layer, can carry out the reading of magnetic state of magnetic recording layer.By detecting the little rotation of the linear polarization state of incoming laser beam after the magnetic recording layer surface reflection, the light that also can carry out the magnetic state of magnetic recording layer reads.The direction that the polarization rotation wherein takes place depends on local magnetic field, for example the magnetized state of recording layer.This effect promptly is usually said Ke Er rotation.

Present invention can be applied to various the rewriting in the medium, characteristic energy modulation and its tracking structure of its recording layer are used to guide the read and write device, and this read and write device produces physical energy in order to write down or read described characteristic changing.The description of the accompanying drawing that hereinafter provides relates to the rewritable optical recording medium with amorphous state and crystalline state recording layer, but is not limited thereto.

Embodiment according to data storage medium of the present invention will be described with reference to the drawings.Should be noted that these accompanying drawings are not pro rata.For example orbital distance is drawn common greatlyyer than them.

Description of drawings

In the drawings:

Fig. 1 has schematically shown the top view of data storage medium, and wherein central area 20 is shown blown up in Fig. 3 and represents in Fig. 5.

Fig. 2 has shown the sectional view along line II-II of indicating among Fig. 1 of the data storage medium that embodiment represents among Fig. 5.

Fig. 3 has shown the zoomed-in view of square area 20 of Fig. 1 of the data storage medium of representing first embodiment.

Fig. 4 has shown the zoomed-in view of square area 20 of Fig. 1 of the data storage medium of representing second embodiment.

Fig. 5 has shown the zoomed-in view of square area 20 of Fig. 1 of the data storage medium of representing the 3rd embodiment.

Embodiment

In Fig. 1 and Fig. 2, represented rewritable data storage medium 1, but it has the regenerative recording layer 9 that is provided with the follower 8 with track.Recording layer 9 has data recorded area 5 and is present in wiped identification marking 3 in the identification marking district 4 that is different from data recorded area 5.Identification marking 3 is crossed over the radius width of a hundreds of track of the tracking structure 8 in the data recording area 5.Data recording area 5 has first tracking structure 8 ', and identification marking zone 4 breaks away from tracking structures substantially or has second tracking structure 8 that in fact is different from first tracking structure 8 ' ".

Rewritable data storage medium 1 can be a kind of optical data memory, but it has the regenerative recording layer of being made up of the material that can change 9 between unsetting and setting state.These type stores media are commonly referred to the phase-change type optical recording.This storage medium has the center pit that has inner periphery 2.Recording layer 9 is present between the circumference and excircle 13 of indicating with sequence number 10.With the zone 5 between the circumference of 11 and 12 indications, there is first tracking structure 8 ', its final user by optical data memory makes to be used for guiding and is used for writing/laser-light write/read head of data in the obliterated data posting field 5.Another kind may be the production period in medium 1 data, for example can be recorded in the approval software that medium 1 is sold the final user in the zone 5.Comprising identification marking 3 by the zone 4 between the circumference of 10 and 11 indications, its production period at data storage medium 1 is written into.Identification marking 3 is made up of the zone with low and high light reflectivity rate, and it is corresponding to the unsetting and setting state of recording layer 9 correspondences.Identification marking 3 also may reside in the radius 12 and the zone 4 ' between the excircle 13 of dish, and wherein the description for zone 4 tracking structures that provide is applicable in view of the above.For example the identification marking 3 of bar code can be represented a sequence number.During copy-protected content being recorded in zone 5 by manufacturer, data are used based on the key of this sequence number encrypted.Only when the sequence number of being represented by identification marking during corresponding to the key of data, data could be decrypted.

In Fig. 3, in fact identification marking zone 4 breaks away from tracking structure.Identification marking zone 4 can still comprise the continuation part of first tracking structure 8 ' that has data recording area, and for example the proximity data posting field 5.Identification marking 3 is present in the identification marking zone 4.In the major part in identification marking zone 4, lack tracking structure prevent optical recorder laser read/write head tracking and wipe identification marking 3 continuously.

In Fig. 4, second tracking structure 8 " comprise the track 6 of at least one spiral groove shape, it is interrupted at least one position.In this embodiment, spiral groove is interrupted at the several position place.Can not carry out the tracking of laser read/write head at interruptive area, therefore the continuous erase to identification marking 3 is suppressed.

In Fig. 5, second tracking structure 8 " comprise the track 6 of a plurality of concentric grooves shapes.Laser read/write head will remain locked in the concentric grooves during following the tracks of.Just can be wiped free of in this part identification marking 3 above concentric grooves, but remain complete in the major part and the non-grooved area of the above-identified mark 3 of all other concentric grooves.

Should be noted that the explanation of embodiment above-mentioned does not limit the present invention, those of skill in the art can design the embodiment of a lot of changes in the scope that does not break away from claims.In the claims, the sequence number between parenthesis should not be construed as the restriction claim.Word " comprises " that not getting rid of those is not listed in the element in the claim and the existence of step.Do not get rid of the existence of a plurality of this elements at the word " " of element front.The minimum fact is to have narrated the measure of determining and do not mean that the mixing of these measures can not be used valuably in different mutually dependent claims.

According to the invention provides the erasable data storage medium, it has the wiped identification marking that is present in the identification marking zone that is different from data recording area.Data recording area has first tracking structure, and in fact the identification marking zone breaks away from tracking structure, perhaps have second tracking structure that in fact is different from first tracking structure, so utilize the storage of subscriber data register that wiping of identification marking is suppressed.

Claims (5)

1. a rewritable data storage medium (1), its have be provided with follower (8) with track but regenerative recording layer (9), described layer (9) has data recording area (5), with the wiped identification marking (3) that is present in the identification marking district (4) that is different from data recorded area (5), and identification marking (3) is crossed over the radius width of several tracks of the tracking structure (8) in the data recording area (5), it is characterized in that, data recording area (5) has first tracking structure (8 '), and identification marking zone (4) do not have tracking structure basically or have second tracking structure that in fact is different from first tracking structure (8 ') (8 ").

2. a rewritable data storage medium as claimed in claim 1 (1) is characterized in that, second tracking structure (8 ") comprises the track (6) of at least one spiral groove shape, and this track is interrupted at least one position.

3. a rewritable data storage medium as claimed in claim 1 (1) is characterized in that, second tracking structure (8 ") comprises the track (6) of a plurality of concentric grooves shapes.

4. the rewritable data storage medium as claim 2 or 3 is characterized in that, at least one track (6) of second tracking structure (8 ") utilizes address information modulated.

5. one kind as claim 1,2 or 3 rewritable data storage medium, it is characterized in that recording layer (9) comprises the magnetic material that can change between first and second magnetized states, and the information that is recorded reads in the mode of selecting from magnetic and light method in recording layer (9).

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