JP2002260243A - Optical information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical information recording medium which can be used in a conventional drive and has an increased recording capacity without violating a standard imposed on a disk, and which can perform stable reading. provide. SOLUTION: A track pitch and a linear velocity in a lead-in area are almost the same as those in the conventional example. On the other hand, in the program area and the lead-out area, at least one of the track pitch and the linear velocity is smaller than that in the lead-in area. In the transition region of the track pitch and the linear velocity, these do not suddenly change but gradually change. Therefore, there is no abrupt and large disturbance in the tracking control or a sudden change in the reading speed, so that stable reading can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc,
The present invention relates to optical information recording media represented by R, CD-RW, DVD-R, DVD-RW, etc. More specifically, information is recorded in an area used by a user in these optical information recording media. It is about what was done.

[0002]

2. Description of the Related Art Optical information recording media such as optical discs and magneto-optical discs have been widely used as data recording media and audio information recording media in recent years.
CD-R, CD-RW, DVD-R, DVD-RW, and the like have been used. In these optical information recording devices, information such as fine pit marks or the like provided on the surface of a disk-shaped recording medium or changes in properties of a film provided on the surface of a disk-shaped recording medium due to magnetism are used as information. Information is recorded by using optical means.

Some of the meanings of terms relating to the optical information recording medium of such a system are described in JIS X6261.
"130mm write-once optical disc cartridge", JISX6
271 "130 mm rewritable optical disk cartridge", and in this specification, the terms described therein are used in the meaning described therein unless otherwise specified.

[0004] In these optical information recording media, meandering grooves and lands are alternately provided spirally, and information is usually written on the grooves. The grooves and lands are used for position control for causing the optical pickup of the recording or reproducing apparatus to travel along the zone where information is written, that is, for position detection for performing tracking. That is, the intensity of the reflected light varies depending on the position of the groove or the land where the light is irradiated. Therefore, the recording or reproducing apparatus receives the signal, controls the position of the optical pickup, and writes information. Control is performed so that light is accurately applied to the current position.

[0005] Of these optical information recording devices, C
In the DR, CD-RW, and the like, a standard called Orange Book is defined, and according to the standard, the inner circumference of a disc-shaped optical information recording medium (hereinafter, may be simply referred to as a “disk”). From the PCA (Powe
r calibration area), PMA (Program memoryar)
ea) area, a lead-in area, a program area, and a lead-out area are to be provided. The PCA area is an area for trial recording by a recording drive, and is used for PM recording.
Area A is an area for recording the memory usage status of the optical information recording medium.

[0006] The lead-in area is an area for recording control information to be given to a recording device, a recording / reproducing device or the like when recording information on the optical information recording medium or reading information from the optical information recording medium. . The program area is used by a user to write and read information, and is an area that can be used by the user. The lead-out area is provided outside the program area, and is used to restore the tracking when the tracking of the optical pickup provided in the recording apparatus or the reproducing apparatus is shifted and goes out of the program area.

In such an optical information recording medium,
Increasing the recording density of information by reducing the track pitch as much as possible or decreasing the linear velocity (m / s) used for recording and reproducing information can record more information on the same optical information recording medium. It is possible because it is possible. Also, if the program area can be made as large as possible, it is possible to record a large amount of information on the same optical information recording medium.

As a technique corresponding to the former, Japanese Patent Application Laid-Open No. Hei 10-222874 discloses a technique of reducing a track pitch in a program area and increasing a recording linear density (corresponding to a linear velocity). ing.

Generally, the resolution of an optical pickup is determined by the wavelength of light used and the numerical aperture (NA) of an optical system.
Therefore, in this technology, a wavelength shorter than the wavelength and the numerical aperture (λ = 780 nm, NA = 0.45) that are usually used,
By using a high NA (λ = 635-685nm, NA = 0.6) and increasing the resolution, the track pitch is reduced and the recording linear density (corresponding to the linear velocity) is increased. As a result, the recording capacity is increased. Is increasing.

However, when a short wavelength, high NA optical pickup is used and recording is performed by a recording apparatus having a small spot size, λ = 780 n, which is normally used, is used.
There is a problem that reading cannot be performed by a reproducing apparatus having an optical pickup with m and NA = 0.45. That is, there is no compatibility with those conventionally used, and a dedicated playback device must be used.

In addition, since the information in the lead-in area cannot be read, it is impossible to even identify the type of the disk. In the invention described in JP-A-10-222874, the disc pitch can be identified even when a conventional reproducing apparatus is used by keeping the track pitch and the recording linear density of the lead-in area unchanged. However, there is no change in that information written in the program area cannot be read.

In the invention described in JP-A-10-222874, as shown in the embodiment,
In the PCA area, the PMA area, the program area, and the lead-out area, the track pitch and the recording linear density are the same, and these are changed only in the lead-in area. This is because the PCA area is an area for trial recording with a recording drive, and the PMA is an area for recording the memory usage status of the optical information recording medium, and therefore, recording and reproduction are performed under the same conditions as the program area. It is based on the notion that it must be done and is inevitable for the invention.

[0013]

As described above,
By using a short wavelength, high NA optical pickup and recording with a recording device with a small light spot size,
Increasing the recording capacity causes a problem that the conventional reproducing apparatus cannot be used. Therefore, another possible method is to make the track pitch as narrow as possible and the linear velocity as low as possible within the allowable limit of the conventional reproducing apparatus.

However, when such a method is employed, when the track pitch or linear velocity is reduced beyond a certain limit and an optical information recording medium whose recording capacity is increased is inserted into the reproducing apparatus, the optical information recording medium may not be used. There is a problem that the information recording medium is hardly recognized by the reproducing apparatus.

Normally, the reproducing apparatus moves the optical pickup to a position near the start position of the lead-in area of the optical information recording medium, pulls in the focus, and recognizes the track of the optical information recording medium. However, when the track pitch in the lead-in area is narrow, the focusing of the optical pickup does not work well, and the optical information recording medium cannot be recognized by the device.

[0016] In view of such circumstances, while using the conventional playback device, to maximize its capabilities,
An optical information recording medium having an increased recording capacity can be recognized by a conventional reproducing apparatus, and it is necessary to obtain a compatible optical information recording medium.

In view of such circumstances, the present inventors have invented an optical information recording apparatus in which the track pitch of the program area is narrower than the track pitch of the lead-in area. He has invented an optical information recording apparatus with a reduced linear velocity, and has filed a patent application as a separate application.

According to an experiment conducted by the present inventors, the track pitch and the linear velocity of the lead-in area were made larger than those of the program area corresponding to high-density recording, so that the optical information recording medium was It has been found that a disc having a large recording capacity can be recognized by a recording or reproducing apparatus. According to experimental results at that time, it has been found that there is no problem in tracking and reading / writing of information even when the track pitch or linear velocity changes suddenly in an area where the track pitch or linear velocity changes, that is, in a transition area.

However, depending on the standard and performance of the device to be developed in the future, if the track pitch or the linear velocity changes abruptly in the transition region, the tracking control system or the reproducing device cannot follow, and a problem may occur. In addition, when manufacturing a master optical disc, a laser cutting machine or the like is used, but due to the response delay of the mechanical system,
Control becomes unstable, and the track pitch and the linear velocity may deviate from the standard.

The present invention has been made in view of such circumstances, and can be recognized by a conventional reproducing apparatus even when the recording capacity is increased, and can perform stable tracking.
An object of the present invention is to provide an optical information recording medium that can be stably processed even by a laser cutting machine when producing a master.

[0021]

In order to solve the above-mentioned problems, a first means of the present invention comprises at least a lead-in area,
In an optical information recording medium having a program area and a lead-out area, a track pitch of the program area is formed to be narrower than a track pitch of the lead-in area, and information is recorded in the program area. An optical information recording medium (Claim 1) characterized in that a track pitch is gradually changed in a transition area.

In this means, the track pitch of the lead-in area is set smaller than the track pitch of the lead-in area, the recording capacity is increased, and the optical information recording medium is easily recognized. Wide. Of course, the track pitch in this case must be a pitch at which a tracking error does not occur more than an allowable value even when applied to a conventional recording apparatus and reproducing apparatus.

In the optical information recording medium, since the lead-in start area and the program start area are determined by the standard, it is preferable to determine the track pitch so as to conform to the standard. The lead-in area start time is also a manufacturer identification code (M-code) and a code (T-code) indicating a recording method (write strategy), so that the manufacturer cannot practically arbitrarily change it. Further, the program area start time from the lead-in area start time is determined by the standard. Therefore, if the track pitch of the lead-in area is also changed, there is a possibility that the disc will become a nonstandard disc. From this aspect, the track pitch in this area is
It is preferred not to unnecessarily narrow it.

According to the experiments of the present inventors, the PCA region,
It is preferable that the track pitch of the program area and the lead-in area is at least 1.3 μm or more. In this case, by setting the lead-in area start position at least within the standard, it can be used in most reproducing apparatuses.

In this means, since the track pitch is gradually changed in the area where the track pitch changes, that is, in the transition area, a large disturbance does not suddenly enter the tracking control system in the transition area.
Tracking is performed accurately. The area where the track pitch is changed may be changed, for example, over the lead-in area and the program area, or may be changed at the beginning of the program area. Note that "gradually" means a rate of change that allows tracking to follow sufficiently stably, and this is the same in other claims (means for solving the problem) that change the track pitch.

In each of the means and claims, "information is recorded in a program area" means that when information is recorded in a program area to which the user can write, a program which cannot be written by the user. This means both cases where information that can be reproduced in advance by a prerecorder, stamper, or the like is recorded in the area.

In this means, since the lead-in area located in the inner peripheral portion has a relatively large track pitch as compared with the program area, a plastic resin such as polycarbonate is formed in a meandering groove pattern on the stamper surface during injection molding. Easy to penetrate (easy to inject).
Therefore, transfer is performed reliably. This occurs because the resin is injected from the inner periphery. In addition, since the releasability of the inner peripheral portion is particularly good also at the time of peeling, a cloud is hardly generated, the inner diameter hole shape can be processed finely, and a substrate with less eccentricity can be manufactured.

In this means, it is preferable from the viewpoint of disc production that the track pitch of the program area and that of the lead-out area are the same. However, it is not always necessary to make the track pitch of the program area equal to that of the program area. It may be larger or smaller than the track pitch.

Next, a second means for solving the above problem is the first means, wherein the transition area of the track pitch starts and ends within the lead-in area. This is a feature (claim 2).

In this means, since the change in the track pitch between the lead-in area and the program area ends in the lead-in area, there is no change in the track pitch in the program area, and stable reading is possible. Become.

A third means for solving the above-mentioned problem is:
The first means or the second means, wherein the track pitch of the lead-out area is narrower than the track pitch of the program area, and the track pitch is gradually changed in the transition area of the track pitch. This is a feature (claim 3).

Since the lead-out area is not an area for recording information, there is no problem even if a tracking error occurs to some extent. Therefore, in the present means, the track pitch of the lead-out area is further narrower than the track pitch at which reading and writing can be performed stably. As described above, the recording time of the lead-out area is determined to be, for example, 1 minute and 30 seconds or more. By narrowing the track pitch, the area of the lead-out area occupying the disk can be reduced. Can be used as a program area, so that the recording capacity can be increased.

In this means, since the track pitch is gradually changed in the area where the track pitch changes, that is, in the transition area, no large disturbance suddenly enters the tracking control system in the transition area.
Tracking is performed accurately. The area where the track pitch is changed may be changed, for example, at the end of the program area, may be changed across the program area and the lead-out area, or may be changed at the head of the lead-out area.

A fourth means for solving the above-mentioned problem is:
In any one of the first means to the third means, the track pitch of the program area is not less than 1.2 μm and less than 1.3 μm (claim 4).

In a conventional recording apparatus and reproducing apparatus having an optical pickup with a wavelength of 780 nm and NA = 0.45, the standard of the track pitch is 1.5 μm to 1.7 μm. Therefore, in this means, the track pitches of the PCA area, the PMA area, and the lead-in area are set to values in this range.
Also, the peak-to-peak value of the signal obtained when the optical pickup crosses the track (push-pull signal)
Is greater than or equal to a predetermined ratio with respect to the magnitude of the signal obtained from the mirror-free mirror surface, tracking can be performed stably by a conventional recording apparatus and reproducing apparatus.

By the way, as a result of performing recording / reproducing with a conventional recording apparatus or reproducing apparatus, according to the knowledge of the present inventors, when the track pitch is 1.1 μm or more, a sufficiently large push-pull signal is obtained. Can be The track pitch is more preferably 1.15 μm or more.

Further, in this means, the track pitch is set to 1.2 μm or more, which is a larger track pitch, so that the productivity of the optical information recording medium according to the present invention is the same as that of the conventional one.

Usually, the optical information recording medium is formed by molding a concave and convex shape into a plastic resin and further forming a necessary reflective film or the like. When molding this plastic substrate, it is formed by an injection molding method using a mold having an inverted shape of the shape formed on the plastic substrate. The time required for the shape of the mold to be transferred to the plastic resin is 6 seconds for a normal track pitch.

Therefore, the present inventors determined the minimum track pitch that can be transferred within this time. As a result, if the track pitch is 1.2 μm or more, the standard molding time of 6 seconds can be sufficient. all right. Therefore, the productivity is the same as that of a conventional CD or CD-R / RW, and it is possible to produce an optical information recording medium having an increased recording capacity while maintaining high productivity.

If the upper limit value of the track pitch in the program area is less than 1.5 μm, the density can be increased. However, in order to obtain complete compatibility in this means, the upper limit value of the track pitch is set to less than 1.3 μm so that tracking can be performed even with a tracking method based on the three beam method, which is currently small. That is,
In the case where the tracking by the three-beam method is applied, if the value is larger than this value, the sub-spot for detecting the tracking error is greatly affected by the bit formed in the adjacent track. This value was set so as not to read the center of. At present, most are one-beam systems, and if only one-beam system is targeted, there is no need to be bound by this upper limit.

A fifth means for solving the above problem is as follows.
In any one of the first to fourth means, wherein the linear velocity of the program area is 1.0 m / s or more and 1.16 m / s.
(Claim 5).

As a result of obtaining the minimum linear velocity at which a minimum mark can be resolved in a conventional reproducing apparatus having a wavelength of 780 nm and NA = 0.45, according to the knowledge of the present inventors, if the linear velocity is 0.90 m / s or more, It was found that it could be resolved. Further, in the present means, the minimum linear velocity necessary for obtaining a sufficient degree of the degree of modulation of the 3T mark and the degree of modulation of the 11T mark with a conceivable reproducing apparatus was determined. As a result, it has been found that if the linear velocity is 1.0 m / s or more, a stable signal can be reproduced from the optical information recording medium at the time of reading.
Further, in this means, the linear velocity is limited to less than 1.16 m / s so that the control is stable even at the time of high-speed writing to the medium.

Next, a sixth means for solving the above-mentioned problem is that, in an optical information recording medium having at least a lead-in area, a program area and a lead-out area, the lead-out area is determined from the track pitch of the program area. An optical information recording medium (claim) wherein the track pitch of the optical information recording medium is formed to be narrow, information is recorded in the program area, and the track pitch is gradually changed in a transition area of the track pitch. Item 6).

In this means, the track pitch of the lead-out area is narrower than the track pitch of the program area. The reason and effect of narrowing the track pitch in the lead-out area and the reason and effect of gradually changing the track pitch in the transition area of the track pitch are the same as those of the third means.

A seventh means for solving the above-mentioned problem is as follows.
In an optical information recording medium having at least a lead-in area, a program area and a lead-out area, the linear velocity of the program area is set lower than the linear velocity of the lead-in area, and information is recorded in the program area. The optical information recording medium is characterized in that the linear velocity changes gradually in the transition area of the linear velocity.

Eighth means for solving the above-mentioned problem is:
The seventh means, wherein the transition area of the linear velocity starts and ends within a lead-in area (claim 11).

A ninth means for solving the above-mentioned problem is:
The seventh means or the eighth means, wherein the linear velocity set in the lead-out area is set lower than the linear velocity set in the program area. ).

A tenth means for solving the above-mentioned problem is that, in an optical information recording medium having at least a lead-in area, a program area and a lead-out area, the linear velocity of the lead-out area is made smaller than the linear velocity of the program area. Is set to be slower, information is recorded in the program area, and in a transition area of the linear velocity, the linear velocity is gradually changed. is there.

In the seventh to tenth means, while the track pitch is changed in the first to third means and the sixth means, respectively, the linear velocity is changed. Only differ. Therefore, each has the same purpose as the first to third means and the sixth means, and has the same effect. In addition,
The term “gradually” refers to a rate of change such that recording and reproduction can sufficiently follow the same stably, and this is the same in other claims (means for solving the problem) that change the linear velocity.

In the seventh means and the eighth means, it is preferable in terms of disc production that the program area and the lead-out area have the same linear velocity. However, it is not always necessary to make them the same. The linear velocity of the out area may be the same as that of the lead-in area.

An eleventh means for solving the above-mentioned problem is any one of the seventh means to the tenth means, wherein the track pitch of the program area is narrower than the track pitch of the lead-in area. (Claim 11).

In this means, any of the above-mentioned seventh to tenth means employs the method of the first means. Therefore, the recording capacity of the program area can be further increased by the synergistic effect of these.

A twelfth means for solving the above-mentioned problem is any of the seventh means to the eleventh means, wherein the track pitch of the lead-out area is narrower than the track pitch of the program area. (Claim 12).

In this means, any of the above-mentioned seventh to eleventh means and the method of the sixth means are employed. Therefore, the recording capacity of the program area can be further increased by the synergistic effect of these.

A thirteenth means for solving the above-mentioned problem is the eleventh means or the twelfth means, wherein a track pitch of a program area is not less than 1.2 μm and less than 1.3 μm. Item 13).

In this means, the above-described eleventh means or twelfth means is further provided with the fourth means. Therefore, an optical information recording medium with high productivity and high recording capacity can be obtained while increasing the recording capacity of the program area by the synergistic effect. Therefore, the storage capacity per unit area is large, and the price can be kept low, so that a high-density recording medium acceptable to consumers can be obtained.

A fourteenth means for solving the above-mentioned problems is any one of the seventh means to the thirteenth means, wherein the linear velocity of the program area is 1.0 m / s or more and 1.16 or more.
m / s or less (claim 14).

In this means, any one of the seventh to thirteenth means is provided, and the fifth means is employed. Therefore, an optical information recording medium with high compatibility, in which the recording capacity of the program area is increased and the recording / reproducing of the program area is ensured while increasing the recording capacity of the program area by the synergistic effect.

A fifteenth means for solving the above-mentioned problem is a disc-shaped optical information recording medium according to any one of the first means to the fourteenth means, wherein The diameter is 8cm and the maximum recording time is 30-40
Minutes (claim 15).

When the diameter of the optical information recording medium is 8 cm,
Recordable time as CD digital audio 30 ~
By forming a program area having a length of 40 minutes, its usefulness is improved, as will be described later, and it can be used as a recording medium of a small-sized photographing device or a recording device.

Incidentally, in the case of an optical information recording medium capable of recording as digital audio for 30 minutes, in the ISO 9660 Mode1 format which is a standard of CD as digital information,
265 MB can be recorded. In the present means, the lower limit of the recording time is limited to 30 minutes in order to ensure that there is no more data on an 8 cm disc at present and to be able to reliably record six songs.

If the time is longer than 40 minutes, the track pitch or linear velocity of the program area in the 8 cm optical information recording medium becomes too small, so that tracking cannot be performed, pits cannot be obtained with a sufficient modulation degree, jitters cannot be obtained. Becomes large, and recording becomes impossible.

A sixteenth means for solving the above problem is any one of the first to fourteenth means, wherein the optical information recording medium is a compact disc. This is a recording medium (claim 16).

According to the present means, it is possible to obtain a compact disk which can have a larger capacity than a conventional compact disk and can be recognized by a conventional reproducing apparatus.

[0065]

Embodiments of the present invention will be described below with reference to the drawings. In the following description of the embodiments and examples, the wavelengths most frequently used at present are
780 nm, a recording device using an optical pickup having a numerical aperture of about 0.45, a reproducing device may be described as an example, but the present invention, except for those specifically limited to that in the column of "means to solve the problem" Therefore, it is not used only for such a recording device and a reproducing device, and a wavelength and a numerical aperture are different.
Therefore, the present invention can be used for a recording device and a reproducing device having different resolutions, and can also be used when a standard conforming to the specifications of such a recording device and a reproducing device is established.

FIG. 1 is a schematic configuration diagram of a physical format of an optical information recording medium represented by a CD-R and a CD-RW according to a first embodiment of the present invention. The right side of FIG. 1 shows the inner peripheral side of the optical information recording medium, and the left side of FIG. 1 shows the outer peripheral side of the optical information recording medium. Optical information recording medium 1
Consists of a non-recording area, a PCA area, a PMA area, a lead-in area, a program area, and a lead-out area from the inner circumference to the outer circumference. The meandering pre-groove 2 is formed in the optical information recording medium 1.

The pre-groove 2 is wobbled in a meandering manner based on a signal (ATIP signal) obtained by synthesizing a reference signal having a predetermined frequency and preformat information. In a recording device that writes information on an optical information recording medium,
The reflected light quantity of 2 is demodulated from this pre-groove, and recording and reproduction are performed based on the obtained pre-format information. Note that the pre-groove 2 according to the embodiment of the present invention.
Is FM-modulated at a carrier frequency of 22.05 kHz. This pre-groove 2 is a CD-R or CD-R
It is formed continuously over the W PCA area, PMA area, lead-in area, program area, and lead-out area.

When recording, first, the optical pickup of the recording / reproducing apparatus is moved to the vicinity of the start position of the lead-in area in the inner area of the optical information recording medium 1, and the optical information is recorded at a predetermined rotational speed. The recording medium 1 is rotated. Then, the optical pickup moves to the start position of the lead-in area from the read preformat information. Then, the pre-groove in the lead-in area is demodulated, and the maximum recordable time and
The recommended writing light power and disk application code are read.

Then, trial writing is performed in the PCA area,
Calibration is performed so that the power of the writing light becomes the optimum power. Also, before and after the power calibration, the PMA area is read, and necessary address information is read at the time of additional writing.

Further, the first embodiment of the present invention also considers the following points. That is, when demodulating a pre-groove, focusing must be performed at least at the position where the optical pickup is first located. Therefore, in the first embodiment of the present invention, the PCA area and the PMA area inside the lead-in area are all wider than the program area. By doing so, focusing of the optical pickup can be easily performed, and, in fact, in a program area where information is recorded, a high recording capacity is achieved by reducing a track pitch.

In the standards of CD-R and CD-RW,
The standard specifies that the PCA area has a length of about 22 seconds and 40 frames, and the PMA area has a length of about 13 seconds and 25 frames. While ensuring this length, the CD-ROM according to the present embodiment is set so that the lead-in area start radius falls within the standard.
R and CD-RW are formed.

By the way, the starting radius of the lead-in area and the starting radius of the program area are determined at predetermined positions.
The lead-in area start time is determined by the manufacturer identification code (M-
code) and the recording method (write strategy)
, Which cannot be arbitrarily changed by the manufacturer. Further, the program area start time from the lead-in area start time is determined by the standard. Then, the size of the lead-out area is also 1 in terms of recording time.
The standard specifies that the time is 30 minutes or more.

In order to sufficiently satisfy such a standard, P
The track pitch of each of the CA area, the PMA area, and the lead-in area was set to about 1.5 μm to 1.7 μm as in the related art. Also, the linear velocity is preferably around 1.2 m / s. In this way, a conventional recording / reproducing apparatus has sufficient compatibility.

In the first embodiment of the present invention, the track pitch gradually changes in the portion where the track pitch changes. This region is referred to as a transition region of the track pitch in this specification. In the first embodiment, as shown in FIG. 1, the transition area A of the track pitch is provided in the lead-in area. The pitch gradually decreases in the latter half of the lead-in area, and the change in the track pitch ends in the lead-in area. By gradually changing the track pitch in this manner, there is no possibility that a large disturbance enters the tracking control device to disturb the tracking, or that the recording and reproduction speed changes suddenly to cause an error. Further, since there is no change in the track pitch in the program area, stable writing and reading can be performed.

FIG. 2C shows the arrangement of the recording areas and the track pitch in each area in the first embodiment.

In FIG. 2, (a) shows the arrangement of the recording areas of the optical information recording medium. The recording area has no groove from the center, the PCA area, the PMA area, the lead-in area, the program area, The lead-out area is followed by a non-recording area having no groove.

FIGS. 2B to 2E are diagrams showing the distribution of track pitch or linear velocity corresponding to each area. (B) corresponds to a conventional optical information storage medium such as a CD-R, and has a constant track pitch and linear velocity in the PCA area, PMA area, lead-in area, program area, and lead-out area. .

FIG. 2C corresponds to an optical information storage medium such as a CD-R according to the first embodiment of the present invention.
The track pitch is larger in the PCA area, PMA area, and lead-in area than in the program area in order to ensure that information recorded in these areas can be written and read.

On the other hand, in the program area and the lead-out area, the track pitch is set to the PCA area, P
It is smaller than those in the MA area and lead-in area. Thus, the recording density of the program area is improved. A transition area A of the track pitch is provided in the latter half of the lead-in area, and the track pitch gradually decreases in the transition area A and becomes a predetermined track pitch at the start of the program area. Therefore, the followability of the optical pickup of the reproducing apparatus or the recording apparatus is improved, and the tracking error hardly occurs.

The minimum required track pitch in the program area is 1.1 μm. If the track pitch is wider than 1.1 μm, a conventional recording apparatus and reproducing apparatus can obtain a push-pull signal for tracking control. Preferably, if the track pitch is 1.15 μm or more, a sufficiently large push-pull signal can be obtained with a margin.

However, if the track pitch is too narrow, the productivity is reduced during the production of the optical information recording medium. Therefore, in the first embodiment of the present invention, the thickness is set to 1.2 μm or more.

Usually, a stamper having a shape corresponding to a land and a groove is used for manufacturing a CD-R, a DVD-R, a CD-R and a CD-RW. The stamper is a mold for forming lands and grooves on a plastic substrate. A plastic substrate is molded by an injection molding method using this stamper. The optical information recording medium is manufactured by forming a dye layer and a phase change layer on a molded plastic substrate, and further forming a necessary reflection film and the like.

When molding this plastic substrate,
It is necessary to allow the plastic resin to sufficiently spread over the uneven surface of the stamper, and to cool and solidify the resin. In a conventional optical information recording medium, this time is 6 seconds. And other processes for manufacturing the optical information recording medium,
It is set to synchronize with this time. Thus, the conventional optical information storage medium such as a CD-R is manufactured at a low price. In order to maintain the productivity of the optical information recording medium according to the first embodiment of the present invention, it is not necessary to spend much time in the plastic substrate molding step.

It is possible to shorten the time required to sufficiently spread the uneven surface of the stamper surface by increasing the mold temperature or improving the mold clamping force. However, when the former method is employed, the cooling time is increased and the time spent is increased. In addition, if the latter method is adopted, the mold clamping device itself must be changed, resulting in an increase in cost. Therefore, the present inventors have studied the track pitch for enabling molding in 6 seconds even when using the conventional plastic substrate molding process.
It has been found that such a condition is satisfied if it has m or more.

If the upper limit of the track pitch in the program area is less than 1.5 μm, high density can be achieved. Further, in order to obtain complete compatibility in the present means, the upper limit of the track pitch is set to less than 1.3 [mu] m so that tracking can be performed even with the three-beam tracking, which is currently small. If the value is larger than this value, the sub spot for detecting the tracking error is greatly affected by the mark formed on the adjacent track. Therefore, this value is set so that the sub spot does not read the center of the adjacent track. . Even if there is a sub-spot on the periphery of the adjacent track and the sub-spot moves along the adjacent track, the track pitch between the target track and both adjacent tracks is equal. Since the track is tracked, there is no problem in tracking.

Next, an optical information recording medium according to a second embodiment of the present invention will be described.

FIG. 3 shows a physical format of an optical information recording medium according to the second embodiment. In the optical information recording medium according to the second embodiment, the linear velocity is reduced instead of decreasing the track pitch. In particular,
The linear velocities in the PCA area, the PMA area, and the lead-in area are large enough to conform to the standard. On the other hand, the linear velocity is lower in the program area and the lead-out area than in the PCA area, the PMA area, and the lead-in area. Therefore, the recording density of the program area is increased, and the area of the lead-out area can be reduced, so that the recording capacity can be increased.

Note that the linear velocities are set in the PCA area, the PMA area,
The reason why each area of the lead-in area is larger than the program area is as follows.

In a conventional recording / reproducing apparatus, in order to recognize the optical information recording medium 1, focusing is performed as described above, and tracking control is performed. Further, the recording / reproducing apparatus obtains an ATIP signal from a pre-groove obtained for rotating the information recording medium at a predetermined linear velocity. Conventional optical information recording medium has a linear velocity of 1.2 m
/ S to 1.3 m / s with a carrier frequency of 22.05 kHz A
A TIP signal is obtained. However, if the linear velocity is reduced in all areas of the optical information recording medium in order to increase the recording capacity, the optical information recording medium will be driven to rotate at a normal rotation speed at the start of rotation driving.

Therefore, the AT obtained from the optical pickup
The carrier frequency of the IP signal will be higher than 22.05 kHz. It is sufficient that the circuit for controlling the rotation of the optical information recording medium can pull in to a sufficiently high frequency, but it does not always mean that it can be pulled in to a certain or higher frequency. Further, the inability to pull in the ATIP signal makes it impossible to control the rotation of the optical information recording medium or the movement of the pickup.

Therefore, in the second embodiment of the present invention, in order to apply to all recording / reproducing apparatuses, the PCA area, the PMA area, and the lead-in area are the same as those of the conventional optical information recording medium. The linear velocity was on the order of magnitude.

In the case of the optical information recording medium according to the second embodiment and the master disk of the disk for manufacturing the optical information recording medium, when the linear velocity is reduced, the optical information recording medium is formed in the rotation direction of the medium. This can be achieved by reducing the length of one cycle of the meandering amplitude of the pregroove. Therefore, when forming a disk having a wobble-shaped pre-groove or its master, the linear velocity can be reduced by shortening the length of the meandering amplitude consumed in one cycle.

A transition area A of the linear velocity is provided between the lead-in area and the program area so that the linear velocity does not change suddenly. By providing the transition region in which the linear velocity gradually changes, no load is imposed on the motor for rotating the medium and its control device.

Incidentally, the linear velocity in the program area was set as follows. Wavelength 780nm, NA = 0.45
As a result of obtaining the minimum linear velocity on condition that the minimum mark is long enough to resolve the minimum mark in the recording apparatus and the reproducing apparatus having the conventional optical pickup, according to the knowledge of the present inventors, the linear velocity Is found to be resolvable if is 0.90 m / s or more. Therefore, by setting the linear velocity of the program area within the above range, the storage capacity is greatly increased.

Further, the present inventors have proposed a reproducing apparatus and a recording / reproducing apparatus in which the degree of modulation by the 3T mark (hereinafter, referred to as “I3”) and the degree of modulation of the 11T mark (hereinafter, referred to as “I11”) are considered. Thus, the minimum linear velocity for obtaining a sufficient value was determined. As a result, it has been found that when the linear velocity is 1.0 m / s or more, a stable signal can be reproduced from the optical information recording medium at the time of reading and writing. At this speed, the jitter can be achieved at 35 ns or less,
Good signals can be written and read.

The distribution of the linear velocities corresponding to the respective regions in the second embodiment of the present invention is as shown in FIG. At this time, the vertical axis is considered as the linear velocity in FIG.

As described above, in the first and second embodiments of the present invention, the track pitch or linear velocity of the program area is made smaller than that of the PCA area, the PMA area, and the lead-in area. At wavelength λ = 780 nm, NA
It is possible to obtain a high-density optical information recording medium that can be used even with a conventional recording / reproducing apparatus of about 0.45.

Further, not only one of the track pitch and the linear velocity in the program area is reduced, but also both the track pitch and the linear velocity are set in the PCA area and the PM.
By making the area smaller than the area A and the lead-in area, the recording capacity can be further improved. Note that the optimum track pitch and linear velocity in the program area are preferably 1.2 μm or more and less than 1.3 μm, and the linear velocity is also preferably 1.0 m / s or more for the above-mentioned reason. Further, the upper limit of the linear velocity is 8 cm CD-R or CD-RW.
1.13 m / s or less is preferable in order to add useful commercial value to

Next, a description will be given of an optical information recording medium according to a third embodiment having a larger storage capacity than that of the above-described embodiment. In this optical information recording medium, at least one of the track pitch and the linear velocity is made smaller in the lead-out area than in the program area. This is because the standard determined in the lead-out area only determines that the time of the lead-out area is 1 minute and 30 seconds or more.
Therefore, the area occupied by the lead-out area can be reduced as long as the recording time standard of the lead-out area is satisfied, and that part can be used as a program area, so that the recording capacity of the program area can be increased. Can be.

A transition area B of track pitch or linear velocity is provided between the lead-in area and the program area, and a transition area C of track pitch or linear velocity is provided near the start of the lead-out area. In the optical information recording medium according to the third embodiment, the transition area B is formed so as to straddle the lead-in area and the program area. The transition area C exists only in the lead-out area.

The distribution of track pitch or linear velocity corresponding to each area in the optical information recording medium according to the third embodiment is as shown in FIG. FIG. 4 shows a schematic diagram of the physical format of the optical information recording medium when the track pitch is changed as in the third embodiment. FIG. 4 is a schematic diagram of the physical format when only the track pitch is changed.

Next, an optical information recording medium in which the recording capacity of the program area is increased without making the track pitch or the linear velocity of the program area smaller than those of the PCA area, the PMA area, and the lead-in area will be described.

In this optical information recording medium, at least one of the track pitch and the linear velocity is smaller in the lead-out area than in the other areas. FIG. 2E shows the linear velocity or the distribution of the linear velocity corresponding to each area of the optical information recording medium. The transition area D was formed at the end of the program area.

In the present optical information recording medium, the area occupied by the lead-out area can be reduced as long as the recording time standard of the lead-out area is satisfied, and that area can be used as a program area. The recording capacity of the area can be increased.

Incidentally, it is preferable that the transition area is not provided in the program area, but is provided, for example, at the end of the lead-in area or the lead-out area. For example,
Although the TOC information is written in the lead-in area, the recording apparatus normally writes the same information repeatedly until the entire lead-in area is filled. Therefore, since necessary information is read at the beginning of the lead-in area, the end of the lead-in area is not required. Therefore, even if the transition region is provided therein, the transition region is less likely to be adversely affected. Further, since no special information is written in the lead-out area, even if a transition area is provided in this area, the transition area is not easily affected by the provision of the transition area.

According to the present invention, as a preferable optical information recording medium, the recording capacity in the program area is reduced by making the track pitch and linear velocity in the program area smaller than those in the PCA area, the PMA area and the lead-in area as described above. Although it is possible to increase, it is more preferable that the linear velocity is the same in the PCA area and the program area.

Normally, in an optical information recording medium such as a CD-R or CD-RW, trial writing is performed in the PCA area in order to calibrate an optimum optical power at the time of writing, and an optimum power for each medium is found. . When writing to the program area, the recommended power value is obtained from the ATIP signal obtained from the pre-groove in the PCA area,
Some marks are written in the PCA area by the laser power whose value is shifted back and forth from the recommended power value. And
The optimum mark is written with the obtained power.

However, if the linear velocity in the PCA area is different from the linear velocity in the program area, the power per unit area changes, so that the write power in the program area may not be an appropriate value. . In order to prevent such a situation, it is preferable that the PCA area and the program area be the same in linear velocity.

In order not to put a burden on a motor for rotating a disk provided in a recording apparatus or a reproducing apparatus, a PCA area, a PMA area, a lead-in area,
It is preferable that the linear velocity be the same over the program area. Instead, the PCA for the track pitch
The recording capacity can be increased by setting the read, write, and write areas with sufficient margins in the area, the PMA area, and the lead-in area, and reducing the size in the program area.

FIG. 5 shows the distribution of track pitch and linear velocity in each area of the optical information recording medium having such a configuration. The solid line in FIG. 5 indicates the linear velocity, and the dotted line in FIG. 5 indicates the track pitch. The transition area of the track pitch is provided in the lead-in area and the lead-out area so that the track pitch does not change in the program area.

As described above, the optimum linear velocity for securing a sufficient recording capacity while keeping the linear velocity constant is 1.0 m / s or more for the above-mentioned reason. Further, the upper limit of the linear velocity is preferably 1.13 m / s or less in order to add useful commercial value to the 8 cm CD-R or CD-RW. Note that 1.16
As a result of experiments by the present inventors, it has been found that speed control becomes difficult when writing at high speed (in particular, about 20 times) when the speed is set to m / s or more.

When the track pitch of the program area is reduced, for example, when recording is performed on a groove, it is preferable that the width of the groove be smaller than the width of the land.

In particular, when the track pitch is reduced, the crosstalk tends to deteriorate. In order to avoid the deterioration of crosstalk, by reducing the width of the groove, within the range where the light spot is irradiated,
It is possible to reduce the proportion occupied by pits formed in adjacent grooves. Therefore, the influence of pits formed in adjacent grooves is reduced, and crosstalk is reduced.

When the track pitch is 1.2 μm or more and less than 1.3 μm, the width of the portion where the recording pit is formed is preferably 300 nm or more and 550 nm or less. Note that 300
The lower limit of not less than nm is the wavelength λ = 750 nm and the numerical aperture N
The width is such that the presence or absence of a pit can be resolved even with an optical pickup of A = 0.45.

Note that this is not limited to the case of groove recording. In the case of land recording, a similar effect can be expected by reducing the land width. In the case of a CD-R in which the recording layer is formed of a dye, the degree of modulation during pit reproduction is also large.

The track pitch is set in the PCA area, PM
In the embodiment in which the track pitch is increased in the area A and the lead-in area, increasing the track pitch in these areas also has the following features.

By increasing the track pitch in the PCA area where the writing laser power calibration is performed, the focus in the PCA area is easily adjusted, and the influence of the adjacent track is reduced. Therefore, it becomes easy to select an appropriate laser power for the medium.

Also, in the PMA area, the focus can be easily adjusted, and the write information in the program area written in the PMA area can be accurately read. Therefore, the reliability at the time of additional recording on the medium is improved.

Further, as can be said for both the PCA area and the PMA area, the signals recorded in these areas have low jitter and block error rate, and have a low I / O ratio.
3. Both I11 and Spec-in have a margin. Therefore, information recorded in the PCA area and the PMA area can be read with high accuracy, and a stable recording operation can be performed in the recording / reproducing apparatus.

In the case of a CD-R having a track pitch of 1.2 μm or more and less than 1.3 μm as in the first embodiment of the present invention, the conventional CD-R Optimal power is lower than that. Therefore, it is preferable that the recommended power value recorded in the ATIP signal in the lead-in area is lower than the recommended power of the conventional CD-R. According to the experimental results of the present inventors, a preferable range of the recommended power is 4.9 mW or more and 6.5 mW or less at a laser power value at 1 × speed.

If the recommended power is set to be larger than 6.5 mW at the track pitch described above, pits will be formed in the land or groove where no recording is performed in the case of CD-R. Therefore, the block error rate increases. Furthermore, if the recommended power value is 7.2 mW, the optimum power value is out of the power range that can be calibrated in the PCA region.

If the recommended power value is set to 4.9 mW or less, the formed pits become too small this time.
Good pits are not formed. Since the optimum power is 7.2 mW formed at the conventional track pitch, the recommended power is set low in advance at such a low level, and a meandering groove corresponding to the power value is formed in the lead-in area in advance. Thus, the recording / reproducing apparatus can surely select the optimum power.

In recent years, CD-ROMs capable of high-speed recording and reproduction have been developed.
RW has been proposed. Particularly, a writing speed of about 4 to 10 times can be obtained. The one that stipulates this standard is Orange Book Part 3, Vol.2, Ver1.0. In this standard, as a difference from the conventional CD-RW,
There is a 30 second Time Jump in the PCA area. There is a part without an ATIP signal in the middle part of the PCA area. In the case where only the lead-in area introduced in the conventional technique is widened and the track pitch and linear velocity are reduced in order to increase the recording capacity in the other areas, the Time Jump portion is formed at a position different from the conventional one. Therefore, when performing test writing in the PCA area, there is a possibility that stable control may not be performed. However, such a problem does not occur in the present invention. Thus, an optical information recording medium having high versatility is obtained.

When the program area is narrowed, the influence of the eccentricity of the medium increases. Therefore, according to the findings of the present inventors, the PCA region, the PMA region
When the program area is made narrower than the area and the lead-in area, the eccentricity is preferably set to 30 μm or less.

When manufacturing a master of such a disk, processing corresponding to grooves and prepits is performed by a laser cutting machine or the like, and the processing is performed by moving a table for fixing the master to these processing machines. There are a table moving type and a pickup moving type that performs processing by moving a processing tool such as a laser. When changing the track pitch, the pickup moving method has a faster response and better tracking accuracy, but the table moving method is superior in terms of the processing accuracy of the entire disc, so use both as appropriate. Is preferred.

When the table moving method is applied to form a highly accurate track pitch, the driving circuit for driving the table is not a conventional method of inputting a signal relating to the track pitch only once. It is necessary to provide control means for detecting a position at a position in the radial direction, inputting a signal of the track pitch in accordance with the position, and inputting a signal of the track pitch to the position in the radial direction as needed. .

Next, a method of manufacturing a stamper applicable to the optical information recording media of the first to third embodiments of the present invention is shown in FIG. A description will be given with reference to FIG.

A blue plate glass is processed into a donut-shaped disk as a substrate material to obtain a substrate 3. Thereafter, the substrate surface is precisely polished to a surface roughness: Ra = 1 nm or less. After the cleaning, a primer and a photoresist 4 are spin-coated on the substrate surface in this order. When prebaked, a photoresist layer 4 having a thickness of about 200 nm is formed on each substrate 3 (1).

Next, using a laser cutting device,
The photoresist 4 on the substrate 3 is exposed. The pattern of the exposure is a pattern corresponding to the grooves and prepits of the optical information recording medium according to the present invention.

The exposed resist 4 on the substrate 3 is developed with an inorganic alkali developer. The resist surface is spin-cleaned and then post-baked. Thereby, a resist pattern is formed (2).

Next, the master 3a is set in a sputtering apparatus, and a Ni layer 5 (conductive layer) is deposited on the surface.
Turn on. This completes the conductivity treatment. Then, by conducting electricity, Ni electroforming is performed to obtain a Ni plating layer 5 having a predetermined thickness (3). Then, when the Ni plating layer 5 is peeled off from the master 3a, a first mold 5a is obtained (4).

A protective coating (for example, trade name: Clincoat S (manufactured by Fine Chemical Japan)) is applied to the uneven surface of the first mold 5a by spin coating. After application, the coating is allowed to air dry. Thereby, the uneven surface is covered with the protective coat. After polishing the back surface of the first mold 5a, the inner diameter and the outer diameter are punched out and dropped. Thus, a donut-shaped first molding die 5a is completed.

The master 3a after peeling off the first mold 5a is not damaged. Therefore, after cleaning the master 3a,
By performing this step again, a plurality of first molds 5a can be obtained. When a stainless steel substrate is bonded to the back surface of the first mold 5a with an epoxy adhesive, the planarity of the first mold 5a is improved.

Next, an ultraviolet curable resin liquid is prepared. The number of colors (APHA) of the resin liquid is 30 to 5 in consideration of heat and light absorption characteristics, mold release properties, light resistance, durability, and hardness.
0, a refractive index of about 1.4 to 1.8 at 25 ° C. is preferable.
A resin liquid having a specific gravity of about 0.8 to 1.3 at 25 ° C and a viscosity of about 10 to 4800 CPS at 25 ° C is preferable from the viewpoint of transferability.

Separately, a blue glass disk 7 is prepared. Then, the disc is washed, and a silane coupling agent as a primer is applied to the surface, and then baked. Then, the resin liquid is dropped on the first mold 5a having the uneven surface facing upward. Then, the glass disk 7 is pressed from above, and the resin liquid 6 is sandwiched between the glass disk 7 and the first molding die 5a. At this time, care was taken to prevent bubbles from entering the resin liquid 6. Further, the glass disk 7 is pressed to uniformly spread the viscous resin liquid 6 over the entire surface of the first mold 5a.

The resin liquid 6 is irradiated with ultraviolet rays from a mercury lamp through the glass disk 7. As a result, the resin liquid is hardened to form the second mold 6a made of a hard resin layer (5). Next, the second mold 6a is separated from the first mold 5a. The second mold 6a has an integral structure with the glass disk 7 as the base (6).

The first mold 5a left after peeling is
Since it is not damaged, it can be used repeatedly. Therefore,
Many second molding dies 6a can be formed from one first molding die 5a. The manufacture of the second mold 6a is easy, and 15 to 6
One sheet can be manufactured in 0 minutes.

Next, a third mold ("metal stamper") made of metal is formed based on the second mold 6a. The manufacturing method is the same as the method for manufacturing the first mold 5a. That is, the second mold 6a is set in a sputtering apparatus, and a Ni layer 8 (conductive layer) is adhered on the surface.
sition. This completes the conductivity treatment. Then, by energizing, Ni electroforming is performed, and N
An i-plated layer 8 is obtained (7). Then, when the Ni plating layer 8 is peeled off from the second mold 6a, a third mold 8a is obtained (8).

A protective coating (for example, KLINCOAT S (manufactured by Fine Chemical Japan Co., Ltd.)) is applied to the uneven surface of the third mold 8a by spin coating. After application, the coating is allowed to air dry. Thereby, the uneven surface is covered with the protective coat. After polishing the back surface of the third mold 8a, the inner and outer diameters are punched out and dropped. Thus, the donut-shaped third molding die 8a is completed. This third mold is used as a stamper for actually manufacturing a disk.

The present inventor manufactured an optical information recording medium by changing the track pitch and the linear velocity of the program area as described in the following examples by using such a manufacturing method. I found something.

As described above, in the case of the optical information recording medium in which the track pitch is narrowed in the program area, the eccentricity must be 30 μm or less. Has to be found below 10 μm in our experiments. Therefore, when manufacturing the stamper, it is preferable to set the eccentricity to 10 μm or less.

By the way, as a result of the inventor's intensive studies,
By setting conditions in at least the following ranges in the program area, writing to the program area by a recording device based on the CD-R and CD-RW standards and reading of information recorded in the program region by a reproduction device And it is possible to obtain a higher recording capacity than conventional CD-R and CD-RW.

The conditions are that the track pitch of the program area is 1.2 μm or more and less than 1.3 μm, and the linear velocity of the program area is 1.0 or more and less than 1.13 μm. In particular, this range is defined as CD-R and C
By applying to the D-RW, the utility value of the 8 cm CD-R / RW can be greatly improved.

By the way, when the track pitch is less than 1.2 μm, in a recording apparatus or a reproducing apparatus having an optical pickup having a wavelength λ = approximately 780 nm and a numerical aperture NA = 0.45, if the track pitch is 1.1 μm or more, the optical pickup is The peak-to-peak value (push-pull signal) obtained when traversing the track is obtained to such an extent that tracking can be sufficiently performed as compared with a signal obtained from a mirror portion having no groove.

Therefore, if the track pitch is 1.1 μm or more, tracking becomes possible, and tentative recording / reproduction becomes possible. However, as described above, the productivity of compact discs including CD-Rs and CD-RWs is reduced. Therefore, the commercial value of CD-Rs and CD-RWs whose prices have been reduced is reduced. On the other hand, the present inventors have conducted intensive studies and found that the conventional CD
In order to obtain the same productivity as that of -R and CD-RW and achieve high-density recording, it has been found that the track pitch is preferably set to 1.2 μm or more.

According to a preferred embodiment of the present invention, the track pitch is smaller than 1.3 μm. The reason for this is that, as described in the first embodiment, tracking can be performed even if tracking is performed using a three-beam system, which is now rare.

According to the present invention, the linear velocity is 1.0 m /
It is preferably at least s. Track pitch 1.0μ
m, wavelength λ = around 780 nm, numerical aperture NA =
In a recording apparatus and a reproducing apparatus having an optical pickup of 0.45, if the track pitch is 0.90 μm or more, the minimum mark does not become smaller than the resolution of the optical pickup. Therefore, the minimum mark can be read by a conventional reproducing apparatus, but in the present invention, I3 and I11 are
As a result of obtaining the minimum linear velocity so that the linear velocity falls within the range of 0.3 to 0.6, the jitter becomes 35 ns or less, and the block error rate becomes 50 or less, the linear velocity becomes 1.0 m / m.
s was found to be playable.

This is because if the linear velocity is too low, the rotational speed of the motor that can rotate stably becomes lower than the lower limit value, especially when recording or reproducing the outer program area. Therefore, in the case of a CD-R / RW having a diameter of 8 cm, if the linear velocity is 1.0 m / s, the rotational speed in the outer program area is within the rotational speed of the motor that can rotate stably. It is thought that this is because it does not decrease.

Next, according to the findings of the present inventors, the upper limit of the linear velocity is preferably set to 1.13 μm or less. If it is 1.13 μm, it is possible to shorten the recording time for a CD-R / RW having a diameter of 8 cm to 30 minutes or more. Incidentally, the format at that time is a case where recording is performed in a CD digital audio format (a sampling frequency of 44.1 kHz, a quantization number of 16 bits, and two channels (right and left)). Also, the CD-ROM format, that is,
265MB when recorded in ISO9660Mode-1 format
That is all.

By the way, most of consumer applications that record data on CD-R / RW discs use only half of the data capacity of the current 80 minutes (700 MB) of CD-R discs. It is the current situation. The reason is that the software itself does not require such a large capacity, and the portable information terminal such as a notebook personal computer or a mobile uses a large capacity, which is rather inconvenient.

Therefore, the present inventors have already standardized the size of the medium on CDs so that the widely used CD-R / RW can obtain a necessary and sufficient capacity even with a smaller medium. Select a medium with a size of 8 cm,
As a result of intensive examination of the capacity that does not actually cause a problem, 265M
An attempt was made to develop an 8 cm CD-R / RW having a size of B or more, and the present invention was achieved.

As a use of the CD-R / RW optical information recording medium for consumer use, image recording and music data recording are popular. By the way, in the case of digital video which is now widespread, one hour recording is common. The recording capacity used at this time is 300 MB. Also, MP
The required capacity of a one-hour moving image by EG4 is also 300 MB. Therefore, a compact medium of 8 cm CD-R / R
By setting the track pitch and the linear velocity at W, the recording capacity can be substantially the same. Therefore, it can be used as a digital video recording medium.

This medium can be reproduced by a widely used recording / reproducing apparatus equipped with an optical pickup having a wavelength λ = 780 nm and a numerical aperture NA = 0.45, so that its use value is improved. In order to obtain the same recording capacity as a digital video tape, about 300 MB is required.
This is the above-mentioned CD digital audio format.
4 minutes. Therefore, it is preferable that the time is 34 minutes or more. However, in the case of 8 cm CD-R / RW, if the length is longer than 40 minutes, the track pitch or the linear velocity becomes too large for recording / reproducing, so that it is preferably 40 minutes or less.

As described above, according to the present invention, an 8 cm CD-R which is more compact than a widely spread 12 cm CD-R / RW and has a recording capacity equivalent to that of a digital video tape.
R / RW can be obtained.

That is, for an optical information recording medium having a diameter of 8 cm, when the track pitch and the linear velocity are set so that the recording time is from 33 minutes to 40 minutes, the push-pull signal and the reproduced signal of the formed pits have a wavelength of 780 nm. A conventional recording apparatus and reproducing apparatus having a pickup with a numerical aperture of 0.45 can be obtained with a margin.

Recording and reproduction are possible with an optical information recording medium having a longer recording time, but compared with an optical information recording medium having a recording time longer than this range,
A stable and good signal can be obtained.

It should be noted that the track pitch of the program area is
1.2 μm or more and less than 1.3 μm, linear velocity 1.0 m / s or more and 1.13
When the speed is less than m / s, the minimum mark can be resolved even by a conventional reproducing apparatus, and high-density recording / reproducing becomes possible.
The basic technical idea of the present invention may be applied not only to writable media such as a DR and a CD-RW but also to a read-only CD.

In this specification, the PCA region, PMA
By making the track pitch and linear distance of the area and the lead-in area larger than those of the program area and the lead-out area, in addition to the invention capable of reliably recognizing the optical information recording medium,
An invention for achieving stable and reliable recording on an optical information recording medium is also disclosed. For example, an optical information recording medium in which the track pitch and the linear velocity in the PCA area are larger than those in other areas, the track pitch and the linear velocity in the PMA area are larger than those in other areas, and both the PCA area and the PMA area are different. This is an invention of an optical information recording medium having an area larger than other areas.

According to these inventions, the recording capacity is improved by setting the track pitch and the linear velocity in the PCA area to the same values as those of the conventional CD-R, and reducing the track pitch and the linear velocity in the other areas. PCA
Power calibration of laser light performed in the region can be performed accurately. Therefore, the quality of marks written in other areas is improved.

Further, by making the track pitch and the linear velocity of the PMA area the same as those of the PCA area described above, it becomes possible to perform good recording and reproduction in the PMA area. In particular, since the used program area is recorded in the PMA area, and the power calibration measured for the first time is recorded, it is necessary to accurately reproduce the second and subsequent times. By increasing the track pitch and linear velocity so that such an area can be accurately reproduced, more secure and accurate writing can be performed.

An optical information recording medium that can be recorded and reproduced by a recording / reproducing apparatus capable of recording and reproducing in a format slightly different from the standard of the current compact disc and DVD, but at least a PC
It is necessary to increase the track pitch and linear velocity of the A area or the PMA area so that recording and reproduction can be performed on these areas satisfactorily. Therefore, the present invention is also very effective for such an optical information recording medium.

Next, examples of the present invention will be described below. In the following embodiments, the PCA area and the PMA area are not particularly disclosed, but the optical disc and the stamper of the present embodiment are respectively formed to conform to the standard. Since the optical disk can be used as an optical disk even if it exists between the start of the groove and the start of the PCA area, the PCA area start area and the like are not specified here.

[0163]

Next, examples of the present invention will be described below. In the following embodiments, the PCA area and the PMA area are not particularly disclosed, but the optical disc and the stamper of the present embodiment are respectively formed to conform to the standard. Since the optical disk can be used as an optical disk even if it exists between the start of the groove and the start of the PCA area, the PCA area start area and the like are not specified here.

Example 1 A groove recording type CD-R disk according to the present invention was manufactured. First, outer diameter 200m
A precision-cleaned glass master having a thickness of 6 mm and a thickness of 6 mm was prepared, and a primer was applied to the surface of the master.
Prebaked on a hot plate at 00 ° C. for 10 minutes.
By this process, a coating master with a coating thickness of 180 nm was completed.

Next, a wobbled groove is formed on the coating master by a laser cutting machine. This step is the most important point in the present invention. First, Orange Book Standard 2 which is a CD-R format
According to the Version 3.1 standard, the mastering generator Da3080 made by Kenwood has a lead-in start time of 97:00:00 and a lead-out start time (last possible start time of lead-out area) of 30:10:00. Set.

The exposure start position is 22.0 mm in radius and 22.0 mm in radius.
In the area from to 25.00mm, the track pitch is 1.60μm,
Set the linear velocity as 1.20m / s, radius 25.00-25.10mm
In between, only track pitch from 1.60μm to 1μ in radial direction
Laser cutting was performed at a rate of 0.004 μm with respect to m while decreasing by a fixed amount, and a track pitch was set to 1.20 μm at a radius of 25.10 mm. The laser cutting was terminated when it reached the radial position of 39.10 mm.

Then, development was performed with an inorganic alkali developer (developer made by Shipley) and a diluent in ultrapure water at a concentration of 20% to complete a master master. Next, subjected to a conductive treatment, after electroforming by a technotrans nickel electroforming apparatus, peeled off from the glass master, further 34.00 mm inner diameter, 138.00 m outer diameter
The diameter of m was punched out to complete the nickel stamper.

The stamper was manufactured by Sumitomo Heavy Industries, Ltd.
It was set in a D40 alpha injection molding apparatus, a polycarbonate substrate was produced, and a Ciba Super Green Dye was applied by spin coating using a stamper of the present invention by a CD-R production line (manufactured by Singulars), and a reflective film and a lacquer were further applied. A blank CD-R blank disc was completed.

This blank disc was inserted into a Sanyo Electric CD-R.
When recording was performed under drive conditions of 12 × speed, a total of 30 minutes and 10 seconds could be recorded without any error.

[0170] This disc is set on a CD-CATS device manufactured by Audio Deployment Co., Ltd., and SLD (Start L
ead in Diameter) and SPD (Start Program Diameter)
Was measured, SLD = 45.92 mm, SPD = 49.5 mm
It was able to satisfy the Orange Book standard. As described above, a CD-R disc satisfying the Orange Book standard and capable of recording for a long time could be produced.

Example 2 A CD-R disk according to the present invention was manufactured in the same manner as in Example 1. The lead-in start time was set to 97:00:00, and the lead-out start time (last possible start time of the lead-out area) was set to 30: 10: 0, and the mastering generator Da3080 made by Kenwood was set.

The exposure start position is 22.0 mm in radius and 22.0 mm in radius.
In the area from to 24.95mm, the track pitch is 1.60μm,
Set the linear velocity as 1.20m / s, radius 24.95-25.00mm
In between, only track pitch from 1.60μm to 1μ in radial direction
Laser cutting was performed at a rate of 0.004 μm with respect to m while decreasing the amount by a constant amount, and the track pitch was set to 1.20 μm at a radius of 25.00 mm.

That is, in the present embodiment, the track pitch at the end of the lead-in area is gradually changed at the above ratio. And the radius position 39.10mm as it is
The laser cutting was terminated when reaching.

The blank disk was manufactured using a Sanyo Electric CD-R.
When the recording was performed by a drive and the recording was performed under the recording speed of 12 times, the recording was performed for a total of 30 minutes and 10 seconds without any error.

The disc is set on a CD-CATS device manufactured by Audio Deployment Co., Ltd. for SLD and SP.
When D was measured, SLD = 45.92 mm, SPD = 49.0 m
m, satisfying the Orange Book standard.
As described above, a CD-R disc satisfying the Orange Book standard and capable of recording for a long time could be produced.

Example 3 A CD-R disk was manufactured in the same manner as in Example 1. The lead-in start time was set to 97:00:00, and the lead-out start time (last possible start time of the lead-out area) was set to 30:10:00 in the Kenwood mastering generator Da3080.

The exposure start position is 22.0 mm in radius and 22.0 mm in radius.
In the area from to 25.00mm, the track pitch is 1.60μm,
Set the linear velocity as 1.20m / s, radius 24.95-25.00mm
During this period, laser cutting was performed while reducing the linear velocity only from 1.20 m / s at a constant speed, and the radius was 25.00 m.
At the time point m, the linear velocity was set to be 1.00 m / s.
That is, the track pitch at the end of the lead-in area was maintained as it was, and the laser cutting was terminated when the radial position reached 39.10 mm.

The blank disc was manufactured using a Sanyo Electric CD-R.
When recording was performed under drive conditions of 12 × speed, the recording was completed for a total of 30 minutes and 10 seconds without any error.

The disc is set on a CD-CATS device manufactured by Audio Deployment Co., Ltd.
When D was measured, SLD = 45.92 mm, SPD = 49.0 m
m, satisfying the Orange Book standard.
As described above, a CD-R disc satisfying the Orange Book standard and capable of recording for a long time could be produced.

Example 4 A CD-R disk was manufactured in the same manner as in Example 1. The size of the optical disk is 8
cm. Groove start and ATIP start radius 21m
m, groove end and ATIP end positions 39 mm, lead-in area start time 97:27:00, program area start time 00: 00: 00: 00, lead-out area start time (last possible start time of lead-out area) At 40:10:00, the track pitch from the groove start position to the lead-in start position is 1.52 μm and the linear velocity is 1.2 m / s, the track pitch in the lead-in area is 1.52 μm, the linear velocity is 1.2 m / s, and the program area Has a track pitch of 1.10 μm and a linear velocity of 0.95 m
/ S, the track pitch in the lead-out area was 1.10 μm, and the linear velocity was 0.95 m / s. The track pitch and the linear velocity were changed at a fixed rate from the position of a radius of 24.5 mm in the lead-in area so that the track pitch and the linear velocity of the program area became the end point of the lead-in area.

The long-time CD-R was converted to a 1- to 12-fold speed CD-R.
Record data with an R writer (Plexter),
Recording and reproduction were evaluated by a CD-R standard inspection device (CD-CATS manufactured by Audio Development). This CD-R can record long-time large-capacity recording data of 40 minutes (350 MB), which is 17 minutes longer than the conventional 23-minute limit time. Marks formed in the program area were detected, but performance such as jitter was somewhat poor.

This characteristic was maintained from 1 × speed to 12 × speed writing. However, Pulstec DDU10
In the case of the 16 × speed writing and the 20 × speed writing by 00, it was found that an error occurred at the time of reading in about 5% of the disks.

(Embodiment 5) A CD was produced in the same manner as in Embodiment 1.
An -R disc was manufactured. The size of the optical disk is 8cm
It is. Groove start and ATIP start radius 21 mm, groove end and ATIP end position 39.1 mm, lead-in area start time 97:27:00, program area start time 00: 00: 00: 00, lead-out area start time 34:02:00, groove The track pitch from the start position to the lead-in start position is 1.50 μm and the linear velocity is
1.11m / s, track pitch in lead-in area is 1.50μm
The linear velocity is 1.11 m / s, the track pitch in the program area is 1.23 μm, the linear velocity is 1.11 m / s, and the track pitch in the lead-out area is 1.23 μm and the linear velocity is 1.11 m / s.

The track pitch was changed at a fixed rate from the position of a radius of 24.5 mm in the lead-in area so that the track pitch and the linear velocity of the program area became the end point of the lead-in area.

The long-time CD-R was converted to a 1- to 12-fold speed CD-R.
Record data with an R writer (Plexter),
Recording and reproduction were evaluated by a CD-R standard inspection device (CD-CATS manufactured by Audio Development). As a result, the lead-in start radius was 22.97mm and there was no problem, and the program start radius was 24.81mm.

In addition, as compared with the conventional 23 minute time limit,
Despite the long-time large-capacity recording data of 34 minutes (298 MB), which is as long as one minute, both the land jitter and the pit jitter were as low as about 20 nsec. In addition, pit deviation and land deviation are both spec-in and I3
Both I11 and I11 were spec-in and had a reflectance of 71%.

Further, a low BLER was obtained, the push-pull signal was not a problem, and the tracking was good. This characteristic was maintained from 1 × to 12 × writing. Further, it was confirmed that there was no problem in 16 × speed writing and 20 × speed writing by the Pulse Tech DDU1000, and the performance was maintained.

(Embodiment 6) A CD was produced in the same manner as in Embodiment 1.
An -R disc was manufactured. The size of the optical disk is 8cm
It is. Groove start and ATIP start radius 21 mm, groove end and ATIP end position 39.1 mm, lead-in area start time 97:27:00, program area start time 00: 00: 00: 00, lead-out area start time 34:07:00, groove The track pitch from the start position to the lead-in start position is 1.50 μm and the linear velocity is
1.16m / s, track pitch in lead-in area is 1.50μ
m, the linear velocity is 1.16 m / s, the track pitch in the program area is 1.18 μm and the linear velocity is 1.16 m / s, and the track pitch in the lead-out area is 1.18 μm and the linear velocity is 1.16 m / s.

The track pitch was changed at a constant rate from the position of a radius of 24.6 mm in the lead-in area so that the track pitch and the linear velocity of the program area became the end point of the lead-in area.

The long-time CD-R was converted to a 1- to 12-fold speed CD-R.
Record data with an R writer (Plexter),
Recording and reproduction were evaluated by a CD-R standard inspection device (CD-CATS manufactured by Audio Development). As a result, the lead-in start radius was 22.99mm and there was no problem, and the program start radius was 24.84mm.

In addition, as compared with the conventional limit time of 23 minutes,
Despite the long-time, large-capacity recording data of 34 minutes (298 MB), which is as long as one minute, both the land jitter and the pit jitter were as low as about 18 nsec. In addition, pit deviation and land deviation are both spec-in and I3
Both I11 and I11 were spec-in and had a reflectance of 72%. Further, a low BLER was obtained, the push-pull signal was not a problem, and the tracking was good.

This characteristic was maintained from 1 × speed to 12 × speed writing. Further, it was confirmed that there was no problem with 16-times writing by the Pulse Tech DDU1000, and that the performance was maintained. However, the productivity during the injection molding of the plastic substrate was inferior to that of the first embodiment.

[0193]

As described above, according to the present invention, even if a conventional reproducing apparatus is used, the optical information recording medium can be easily recognized and the recording capacity can be increased. Further, even when the recording capacity of the program area is increased, stable and reliable optical reading from the optical information recording medium can be performed. Further, it is possible to stably process the original disc by using a laser cutting machine.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a physical format of an optical information recording medium according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an arrangement of recording areas of a CD-R according to each embodiment of the present invention and a distribution of a track pitch or a linear velocity in each area.

FIG. 3 is a schematic configuration diagram of a physical format of an optical information recording medium according to a second embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a physical format of an optical information recording medium according to a third embodiment of the present invention.

FIG. 5 is a diagram showing an arrangement of recording areas of a CD-R according to a preferred embodiment of the present invention and a distribution of a track pitch or a linear velocity in each area.

FIG. 6 is a diagram showing a method of manufacturing a stamper which is an example of an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Optical information recording medium 2 ... Pregroove 3 ... Substrate 3a ... Master 4 ... Photoresist layer 5 ... Ni layer 5a ... 1st molding die 6 ... Resin liquid 6a ... 2nd molding die 7 ... Base (glass disk) 8 ... Ni layer 8a ... third mold A, B, C, D ... transition region

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Konishi 3-2-3 Marunouchi, Chiyoda-ku, Tokyo Nikon Corporation F term (reference) 5D029 WA02 WB11 WC01 WD07 5D090 AA01 DD02 EE20 FF17 GG03 GG05

Claims (16)

[Claims] 1. An optical information recording medium having at least a lead-in area, a program area, and a lead-out area, wherein a track pitch of the program area is formed to be narrower than a track pitch of the lead-in area. An optical information recording medium on which information is recorded, wherein a track pitch gradually changes in a transition area of the track pitch. 2. The optical information recording medium according to claim 1, wherein the transition area of the track pitch starts and ends in the lead-in area. 3. The optical information recording medium according to claim 1, wherein a track pitch of the lead-out area is narrower than a track pitch of the program area, and in a transition area of the track pitch, An optical information recording medium characterized in that a track pitch is gradually changed. 4. One of claims 1 to 3
3. The optical information recording medium according to claim 1, wherein a track pitch of the program area is not less than 1.2 μm and less than 1.3 μm. 5. One of claims 1 to 4
3. The optical information recording medium according to claim 1, wherein a linear velocity of the program area is not less than 1.0 m / s and less than 1.16 m / s. 6. An optical information recording medium having at least a lead-in area, a program area, and a lead-out area, wherein a track pitch of the lead-out area is formed to be narrower than a track pitch of the program area. An optical information recording medium on which information is recorded, wherein the track pitch gradually changes in a transition area of the track pitch. 7. An optical information recording medium having at least a lead-in area, a program area, and a lead-out area, wherein a linear velocity of the program area is set to be lower than a linear velocity of the lead-in area. An optical information recording medium on which information is recorded, wherein the linear velocity gradually changes in a transition area of the linear velocity. 8. The optical information recording medium according to claim 7, wherein the transition area of the linear velocity starts and ends within a lead-in area. 9. The optical information recording medium according to claim 7, wherein a linear velocity set in the lead-out area is lower than a linear velocity set in the program area. An optical information recording medium characterized by the above-mentioned. 10. An optical information recording medium having at least a lead-in area, a program area, and a lead-out area, wherein the linear velocity of the lead-out area is set to be lower than the linear velocity of the program area, and An optical information recording medium on which information is recorded, wherein the linear velocity gradually changes in a transition area of the linear velocity. 11. The optical information recording medium according to claim 7, wherein a track pitch of the program area is smaller than a track pitch of the lead-in area. An optical information recording medium characterized by the above-mentioned. 12. The optical information recording medium according to claim 7, wherein a track pitch of the lead-out area is narrower than a track pitch of the program area. Characteristic optical information recording medium. 13. The optical information recording medium according to claim 11, wherein a track pitch of the program area is 1.2 μm or more and less than 1.3 μm. 14. The optical information recording medium according to claim 7, wherein a linear velocity of the program area is not less than 1.0 m / s and less than 1.16 m / s. An optical information recording medium characterized by the above-mentioned. 15. The disc-shaped optical information recording medium according to claim 1, wherein the optical information recording medium has a diameter of 8 cm and a maximum recording time of 30 to 30. An optical information recording medium characterized by being 40 minutes. 16. The optical information recording medium according to claim 1, wherein the optical information recording medium is a compact disc. Medium.