JPH0973635A - Optical information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To narrow a track pitch by sufficiently reducing cross talk. SOLUTION: An optical information recording medium is provided with plural tracks (respective information tracks making solid lines 11-15 a virtual central position), and respective tracks consist of plural sectors, and areas recording header information of respective sectors are adjacent between adjacent tracks. Then, plural tracks are made plural pairs tracks making adjacent two tracks one pair, and header information are formed inverting a polarity of a binary information signal between adjacent pairs. The medium is constituted so that the arrangements of prepits become the same one respectively between the tracks of the solid lines 11, 12 and between the tracks of the solid lines 13, 14, and the prepits aren't adjacent between the tracks of the solid lines 12, 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording medium in which header information such as track number and sector number is adjacent between tracks.

[0002]

2. Description of the Related Art In recent years, in this kind of optical information recording medium, there is a tendency to increase the capacity by high density recording.
As one of the methods, a narrow track pitch has been achieved. A problem in achieving this narrow track pitch is the influence of crosstalk from adjacent tracks, and how to reduce this crosstalk is an issue.

Usually, in a disc-shaped optical information recording medium, the header information such as the track number and the sector number recorded in each information track is binary data which is very similar between adjacent tracks, and therefore is adjacent to each other. The arrangement of pre-pits (concavo-convex pits) in the header area is almost the same between the information tracks. Therefore, when header information is formed adjacently between adjacent tracks, the prepits are adjacent to each other, and the influence of crosstalk from the adjacent prepits is large. JP-A-6-325368
The publication discloses an optical information recording medium in which the crosstalk in the header area is reduced by utilizing the fact that the prepits are arranged in almost the same arrangement between adjacent information tracks.

FIG. 11 is a schematic diagram showing the arrangement of prepits in the header area of each information track of the optical information recording medium disclosed in the above publication.

In FIG. 11, solid lines 111 to 115 are virtual center positions of the respective information tracks, and these solid lines 111
Header information (binary information signal) such as a track number and a sector number is recorded as prepits (pits and projections) along lines 115 to 115. In the header information (binary information signal) recorded on each information track, prepits are formed so that the sign of the binary information signal is inverted for each track, and the prepits are not adjacent to each other between adjacent tracks. Has been done. That is, the solid lines 111 and 11
Pre-pits formed on 3,115 and solid lines 112,
The prepits formed on 114 are not adjacent to each other.

In this optical information recording medium, for example, when reproducing the pre-pit 122 on the solid line 112, the solid line 1
There are no prepits in the portions adjacent to the prepits 122 on 11 and 113, and as shown in FIG. 11, the spot 131 of the reproducing light beam has the prepits 12 on the solid line 112.
This spot 131 when located at the edge of 2
A solid line 111 and a solid line 11 in which a part of the
It overlaps with the pre-pits 121 and 123 on 3 (overlap 141, 142). Thus, although the overlaps 141 and 142 occur near the edge of the pre-pit 122, the overlap is small and the crosstalk is small.

[0007]

However, the conventional optical information recording medium disclosed in the above-mentioned Japanese Patent Laid-Open No. 6-325368 has the following problems.

In consideration of further narrowing the track pitch, in the optical information recording medium having the structure shown in FIG.
When the spot 131 of the reproducing light beam is located approximately in the center between the pits on the solid line 112 (see FIG. 12), the spot 131 and the adjacent solid lines 111 and 1
The overlap with the pre-pits 121 and 123 on 13 becomes large, and the crosstalk amount becomes large. As a result, the level of the reproduction signal fluctuates, which may result in erroneous reading or unstable tracking.

An object of the present invention is to provide an optical information recording medium that solves the above problems, sufficiently reduces crosstalk, and further narrows the track pitch.

[0010]

An optical information recording medium of the present invention has a plurality of tracks, each of the plurality of tracks is composed of a plurality of sectors, and header information of each sector is provided between adjacent tracks. In an optical information recording medium in which recorded areas are adjacent to each other, the plurality of tracks are set as a plurality of pairs of tracks having two adjacent tracks as one pair, and the polarities of the binary information signals are set between the adjacent pairs. It is characterized in that the header information is inverted and formed.

In the above optical information recording medium, a plurality of tracks are composed of a land portion and a groove portion which are formed spirally or concentrically, and adjacent land portions and groove portions may be one pair. .

<Operation> Usually, the header information of the track number and the sector number is formed by pre-pits (uneven pits) or magneto-optical recording (header mark) based on the binary information signal, and it is very difficult to make a gap between adjacent tracks. It will be similar binary data. Therefore, the concavo-convex pits (or header marks) formed in the header area are adjacent to each other between adjacent tracks, and the concavo-convex pits (or header marks) of the adjacent tracks during signal reproduction.
Causes crosstalk. In order to reduce this crosstalk, conventionally, header information is formed by inverting the polarity of a binary information signal between adjacent tracks, and the prepits are not adjacent between adjacent tracks. When pitching is attempted, in the states shown in FIGS. 11 and 12, crosstalk from adjacent tracks is a problem.

In the optical information recording medium of the present invention, each track is made up of a plurality of pairs of tracks, each pair consisting of two adjacent tracks, and the polarities of the binary information signals are inverted between the adjacent pairs. Since the header information is formed and the polarity of the binary information signal is not inverted between the paired tracks, the header information is formed.
As shown in, when the reproduction spot is located approximately in the center between the pits, the spot partially overlaps only the prepits of one adjacent track and does not overlap the prepits of the other adjacent track. Therefore, the crosstalk in the optical information recording medium of the present invention is caused in the conventional optical information recording medium in which when the reproduction spot is located between the pits, a part of the spot overlaps with the pre-pits (or header marks) of the adjacent tracks. On the other hand, since it does not overlap with the pre-pit of the other adjacent track, it becomes smaller and crosstalk does not become a problem. Further, in the optical information recording medium of the present invention, when the reproduction spot is located near the center of the prepit,
Although part of the spot overlaps with the prepits of one adjacent track, but does not overlap with the prepits of the other adjacent track, crosstalk does not pose a problem in this case as well.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram showing the arrangement of prepits in the header area of each information track of the optical information recording medium of the first embodiment of the present invention.

In FIG. 1, solid lines 11 to 15 are virtual center positions of the respective information tracks, and header information such as track numbers and sector numbers are recorded by prepits (pits and projections) along these solid lines 11 to 15. There is. Normally, the header information recorded on each information track is binary data that is very similar between adjacent tracks. Therefore, in this embodiment, two adjacent information tracks are paired (in this case, a solid line). 11 and the solid line 12 and the solid line 13 and the solid line 14 are paired), and the header information is formed by inverting the polarity of the binary information signal between the adjacent pairs, and the binary information is formed between the paired information tracks. The polarity of the information signal is formed without being inverted. That is, the solid line 11 and the solid line 12
The prepits are arranged in the same manner between the tracks of the solid line 13 and the tracks of the solid line 13 and the prepits are not arranged adjacent to each other between the tracks of the solid line 12 and the solid line 13. There is.

In this optical information recording medium, as shown in FIG. 1, the center of the spot 31 of the reproducing light beam is the solid line 12.
When located at the edge portion of the upper pre-pit 22, a part of this spot 31 overlaps with the pre-pits 21 and 23 on the adjacent tracks (solid lines 11 and 13) (overlaps 41 and 42), but the overlap is small and the crossing is small. The talk will be held small.

Further, as shown in FIG. 2, when the center of the spot 31 of the reproducing light beam is located substantially in the center between the pits on the solid line 12, a part of the spot 31 is a solid line 13 of the adjacent track. Only the upper prepit 23 is overlapped, and the prepits on the solid line 11 are not overlapped. As a result, the crosstalk is suppressed small.

The results of specific signal reproduction using the above optical information recording medium will be described below.

FIG. 3 shows an example of a pre-pit reproducing optical head of a general optical information recording / reproducing apparatus.

In FIG. 3, reference numeral 56 is an optical disk provided with the header information as shown in FIGS.
The pre-pit reproducing optical head is arranged so as to face the recording surface of the optical disc 56, irradiates a reproducing light beam on the recording surface, and reproduces pit information by the reflected light thereof. A laser 51, a collimator lens 52 and a beam shaping prism 53, which are sequentially arranged in a traveling direction of a light beam emitted from the semiconductor laser 51.
a, 53b, beam splitter 54, objective lens 55
And a condenser lens 57, a cylindrical lens 58, and a photodetector 59, which are sequentially arranged in the traveling direction of the light beam reflected by the beam splitter 54 through the objective lens 55. ing.

In this pre-pit reproducing optical head, the light beam emitted from the semiconductor laser 51 is collimated by the collimator lens 52 and then narrowed down by the objective lens 55 via the beam shaping prisms 52a and 52b and the beam splitter 54. Optical disc 56
A reproduction light spot having a predetermined diameter is formed on the recording surface.
The light reflected on the recording surface of the optical disc 56 is condensed again by the objective lens 55, reflected by the beam splitter 54, and received by the photodetector 59 via the condensing lens 57 and the cylindrical lens 58. A two-divided photodetector (or a four-divided photodetector) is usually used as the photodetector 59, and a servo signal and an RF signal are obtained based on the output of each divided sensor unit.

The following is a comparison result of reproducing the header information of the optical information recording medium of this embodiment and the conventional one by using the above-mentioned prepit reproducing optical head.

FIG. 4 is a reproduction signal when reproducing the header information of the optical information recording medium of the present embodiment shown in FIGS. 1 and 2 by advancing the spot 31 of the reproduction light beam along the solid line 12. The vertical axis represents the signal level and the horizontal axis represents the relative position of the spot 31. In the figure, the relative position A shows the spot 31 at the position shown in FIG. 1, the relative position B shows the spot 31 at the position shown in FIG. 2, and the reproduced signal in the state without crosstalk is a solid line. , The actual reproduced signal including crosstalk is indicated by the alternate long and short dash line, and the crosstalk is indicated by the broken line.

As can be seen from FIG. 4, when the spot 31 of the reproduction light beam is advanced along the solid line 12, the reproduction signal is such that the level of the reproduction signal is almost minimum when the spot 31 is located at the pit center. A sinusoidal waveform is obtained that is almost maximum when positioned between pits (that is, a portion where no pit is formed). The crosstalk in this case is maximum when the spot 31 is located at the relative position B, that is, when the spot 31 is located between the pits.

FIG. 13 shows the header information of the conventional optical information recording medium shown in FIGS. 11 and 12 as a solid line 112.
The reproduction signal is shown when reproduction is performed by advancing the spot 131 of the reproduction light beam along, and the vertical axis indicates the signal level,
The horizontal axis indicates the relative position of the spot 131. In the figure, the relative position A shows the spot 131 at the position shown in FIG. 11, the relative position B shows the spot 131 at the position shown in FIG. 12, and like FIG. The reproduced signal is shown by a solid line, the actual reproduced signal including crosstalk is shown by a chain line, and the crosstalk is shown by a broken line.

As can be seen from FIG. 13, the reproduced signal in this case also has a sinusoidal waveform like the reproduced signal shown in FIG. 4, and the crosstalk causes the spot 131 to be located at the relative position B. The maximum is when the spot 131 is located between the pits.

Comparing the reproduction signals shown in FIGS. 4 and 13 with each other, when both are at the relative position B,
That is, the crosstalk becomes maximum when the spot is located between the pits, and the crosstalk amount is shown in FIG.
The one shown in is smaller. In the optical information recording medium of the present embodiment, this is the spot 31 as shown in FIG.
In the case where the spots are located almost in the center between the pits, a part of the spot overlaps only with the pre-pits 23 on the solid line 13 of the adjacent track (overlap 42) and does not overlap with the pre-pits on the solid line 11, so that the crosstalk does not occur. Overlap 4
This is because only the data from 2 was obtained, and as a result, crosstalk was reduced.

Since the information (user data) other than the header information is a completely different signal between the adjacent information tracks, the arrangement of the prepits is random, and the prepits are arranged in a random manner as compared with the portion in which the header information is recorded. Crosstalk is small enough.

The arrangement of pre-pits such as the optical information recording medium of the first embodiment described above is applicable not only to the above-mentioned track structure but also to a track guide groove provided between each information track. is there. In the case where the tracking guide groove is provided between the respective information tracks, both the land portion (convex portion) and the groove portion (concave portion) can be used as the information track. In this case,
A track of a land part and a track of a groove part which are adjacent to each other form one pair.

<Other Embodiments> In the optical information recording medium described above, the header information is recorded by the pre-pits, but here, the case where the header information is formed by the magneto-optical recording will be described.

FIG. 5 is a schematic diagram showing the arrangement of header marks in the header area of each information track of the optical information recording medium of the second embodiment of the present invention, and FIG. 6 is a line A- of FIG.
It is A sectional drawing.

The optical information recording medium of this embodiment is an optical disc in which an information track is composed of a land portion (convex portion) and a groove portion (concave portion) which are spirally or concentrically formed. Information tracks 211, 213,
215 is a land portion, and the information tracks 212 and 214 are groove portions (recesses). These information tracks 21
Header marks 1 to 215, which represent header information such as track numbers and sector numbers, are formed by magneto-optical recording. As described above, the header information recorded on each information track is binary data that is very similar between adjacent tracks. Therefore, also in this embodiment, as in the case of the first embodiment described above. , Two adjacent information tracks are made into one pair (here, the information tracks 211 and 212 and the information tracks 213 and 214 are paired), and the header information is set to the polarity of the binary information signal between the adjacent pairs. The polarity of the binary information signal is not inverted between the paired information tracks which are formed by being inverted.
That is, the header marks are arranged in the same manner between the information track 211 and the information track 212 and between the information track 213 and the information track 214, and the information track 212 and the information track 213 have the same arrangement. Header marks are not adjacent to each other between tracks.

In the above optical information recording medium, as can be seen from FIG. 5, when the center of the spot 231 of the reproducing light beam is located at the edge portion of the header mark 222 on the information track 212, part of this spot 231 is Header marks 221 and 22 on adjacent tracks 211 and 213
3 (overlap 241,242). Information track 2
When the header information on 12 is reproduced, crosstalk occurs such that the overlaps 241 and 242 leak as signals.

Further, as shown in FIG. 7, when the spot 231 of the reproducing light beam is located substantially in the center between the header marks on the information track 212, a part of the spot 231 is on the adjacent track 213. Only the header mark 223 will overlap (overlap 24
2) It does not overlap with the header mark on the information track 211. Therefore, the crosstalk at this spot position is only from the overlap 242.

Hereinafter, the results of concrete signal reproduction using the above-mentioned optical information recording medium will be described.

FIG. 8 shows an example of a magneto-optical head of a general optical information recording / reproducing apparatus.

In FIG. 8, reference numeral 256 is the optical disk shown in FIGS. The magneto-optical head is the optical disk 2
56 is arranged so as to face the recording surface, irradiates a light beam for reproduction on the recording surface, and reproduces the header mark by the reflected light.
1, the collimator lens 252, the beam shaping prisms 253a and 253b, the beam splitter 264, the objective lens 255, and the reflected light from the optical disc 56, which are sequentially arranged in the traveling direction of the light beam emitted from the semiconductor laser 251. A condenser lens 257, a beam splitter 268, a photodetector 269, which are sequentially arranged in the traveling direction of the light beam reflected by the beam splitter 54 via the optical path, and are arranged in the traveling direction of the light beam reflected by the beam splitter 268. It is composed of a photo detector 270 and an external magnetic field 271 provided on the back surface of the optical disc 256.

In this reproducing optical head, the light beam emitted from the semiconductor laser 251 is collimated by the collimator lens 25.
After being made into a parallel light flux by 2, the beam shaping prism 25
2a, 252b and the beam splitter 264, and the optical disc 2 is focused by the objective lens 255.
A reproducing light spot having a predetermined diameter is formed on the recording surface 56. The light reflected on the recording surface of the optical disc 256 is condensed again by the objective lens 255, and the beam splitter 26
4 and is incident on the beam splitter 264 via the condenser lens 257. Among the light fluxes that have entered the beam splitter 264, the light flux that has transmitted through the beam splitter 264 is received by the photodetector 269, and the light flux reflected by the beam splitter 264 is received by the photodetector 270.

The above photo detectors 269 and 270
Is usually a two-division photo detector (or a four-division photo detector). In these photo detectors 269 and 270, the total of the returned light intensities is almost unchanged, but the mutual light intensities returned to the respective photo detectors change in opposite phases depending on the presence or absence of the header mark.

When reproducing information, calculation is performed based on the output of each divided sensor unit to obtain the servo signal and RF.
When a signal is obtained and information is recorded, for example, an external magnetic field 2
This is performed by emitting a modulated light beam from the semiconductor laser 251 while applying a magnetic field by 71.

The results of reproducing the header information of the optical information recording medium of this embodiment and the conventional one by using the above-mentioned reproducing optical head are shown below.

FIG. 10 shows the reproduction of the header information of the optical information recording medium of this embodiment shown in FIGS. 5 and 7 when the reproduction light beam spot 231 is reproduced along the information track 212. Signals are also shown, where the vertical axis represents the signal level and the horizontal axis represents the relative position of the spot 231 on the track. In the figure, the relative position A shows the spot 231 in the position shown in FIG. 5, the relative position B shows the spot 231 in the position shown in FIG. 7, and the reproduced signal in the state without crosstalk is a solid line. , The actual reproduced signal including crosstalk is indicated by the alternate long and short dash line, and the crosstalk is indicated by the broken line.

As can be seen from FIG. 10, when the reproducing light beam spot 231 is advanced along the solid line 212,
The reproduction signal has a sinusoidal level in which the level is almost minimum when the spot 231 is located at the center of the header mark and is maximum when the spot 231 is located between the header marks (that is, in the portion where the header mark is not formed). It becomes a waveform. The crosstalk is maximum at the relative position B, that is, when the spot 231 is located between the header marks.

14 and 15 are schematic diagrams showing the arrangement of the header marks in the header area of each information track of the conventional optical information recording medium when the land / groove recording medium is used. 5 and FIG. 7. Here, the information tracks 311, 313, 3
Reference numeral 15 is a land portion and information tracks 312 and 314 are groove portions (recesses).
15, a header mark representing header information is formed by magneto-optical recording. In this recording medium, header information is formed between adjacent information tracks by inverting the polarity of the binary information signal, and between paired information tracks is formed without inverting the polarity of the binary information signal. There is.

FIG. 16 shows the reproduction information beam spot 331 of the header information of the conventional optical information recording medium shown in FIG. 14 and FIG. 15 along the information track 312.
In the figure, the reproduced signal is shown when the reproduction is carried out by advancing and the vertical axis shows the signal level and the horizontal axis shows the relative position of the spot 331 in the track direction. In the figure, A shows the spot 331 in FIG.
In the position shown in FIG.
The ideal reproduction signal without crosstalk is shown by a solid line, the actual reproduction signal including crosstalk is shown by a chain line, and the crosstalk is shown by a broken line.

The reproduced signal in this case also has a sinusoidal waveform like the reproduced signal shown in FIG. 8, and the crosstalk is at the position B, that is, the spot 331 is located between the pits. Sometimes it is maximum.

Comparing the reproduction signals shown in FIGS. 10 and 16, the crosstalk becomes maximum when both are at the relative position B, that is, when the spot is located between the pits. The crosstalk amount is smaller than that shown in FIG. This is because, in the optical information recording medium of the present embodiment, as shown in FIG. 7, when the spot 231 is located approximately in the center between the header marks, the spot is partially on the adjacent information track 213. The header mark 223 of FIG. 2 overlaps (overlap 242) and does not overlap with the header mark on the information track 211. Therefore, the crosstalk is only from the overlap 242, and as a result, the crosstalk is reduced.

In the above-described land / groove recording medium, as shown in FIG. 9, the amount of crosstalk differs depending on the size of the step between the land and the groove, and the step size is λ / 6 to λ / 7. The amount of crosstalk decreases near (where λ is the wavelength of the reproduction light beam). Therefore, the information tracks 211, 213 and 215 and the information track 21
Crosstalk can be reduced by setting the step difference from 2, 214 to about λ / 6 to λ / 7.

Since the information (user data) other than the header information is a completely different signal between adjacent information tracks, the arrangement of the marks formed by the magneto-optical recording becomes random and the header information is recorded. The crosstalk is sufficiently small compared to the part that was exposed.

Although the land / groove recording medium has been described in the present embodiment, it is needless to say that the present invention can be applied to the recording medium having the track structure as in the first embodiment.

As described above, by adopting the optical information recording medium structure described in each embodiment, the track pitch can be further narrowed and crosstalk can be reduced, and the large capacity of the medium can be achieved. Can be realized. Also,
As an optical information recording medium, a ROM (reproduction only) type,
The same effect can be obtained for optical information recording media of all the WORM type (additional write) type and R / W (rewritable) type, and the medium shape is not limited to the disk type, but the card type. May be

[0053]

Since the present invention is configured as described above, it has the following effects.

According to the first aspect of the present invention, as compared with the conventional optical information recording medium, when the reproduction spot is located between the pits, a part of the spot overlaps with the pre-pits (or header marks) of the adjacent tracks. ,
Crosstalk is small because it does not overlap with the prepits of the other adjacent track. Therefore, the crosstalk can be sufficiently reduced, and the track pitch can be further narrowed.

According to the second aspect of the present invention, the track is constituted by the land portion and the groove portion which are formed spirally or concentrically.
There is an effect that it is possible to provide a large-capacity optical information recording medium that exhibits the above effects.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an arrangement of pre-pits in a header area of each information track of an optical information recording medium according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a state in which the center of a spot 31 of a reproduction light beam is located substantially in the center between pits in the arrangement of pre-pits shown in FIG.

FIG. 3 is a configuration diagram showing an example of a pre-pit reproducing optical head of an optical information recording / reproducing apparatus.

FIG. 4 is a graph showing a reproduction signal when reproducing the header information of the optical information recording medium of the present embodiment shown in FIGS. 1 and 2 by advancing a spot 31 of a reproduction light beam along a solid line 12. Is.

FIG. 5 is a schematic diagram showing the arrangement of header marks in the header area of each information track of the optical information recording medium of the second embodiment of the present invention.

6 is a sectional view taken along line AA of FIG.

7 is a diagram showing a state in which the center of a spot 231 of the reproduction light beam is located substantially in the center between pits in the arrangement of the header marks shown in FIG.

FIG. 8 is a configuration diagram showing an example of a magneto-optical head of an optical information recording / reproducing apparatus.

FIG. 9 is a graph showing the relationship between land / groove steps and crosstalk.

FIG. 10 shows a reproduction signal when the header information of the optical information recording medium of the present embodiment shown in FIGS. 5 and 7 is reproduced by advancing a spot 231 of a reproduction light beam along an information track 212. It is a graph.

FIG. 11 is a schematic diagram showing the arrangement of prepits in the header area of each information track of the optical information recording medium disclosed in JP-A-6-325368.

12 is a diagram showing a state where the center of a spot 131 of a reproduction light beam is located substantially in the center between pits in the arrangement of pre-pits shown in FIG.

FIG. 13 is a graph showing a reproduction signal when the header information of the conventional optical information recording medium shown in FIGS. 11 and 12 is reproduced by advancing a spot 131 of a reproduction light beam along a solid line 112. .

FIG. 14 is a schematic diagram showing an arrangement of header marks in a header area of each information track of a conventional optical information recording medium when a land / groove recording medium is used.

15 is a diagram showing a state in which the center of the spot 331 of the reproduction light beam is located substantially in the center between the pits in the arrangement of the header marks shown in FIG.

FIG. 16 shows the information track 312 of the header information of the optical information recording medium of the present embodiment shown in FIGS. 14 and 15.
6 is a graph showing a reproduction signal when reproduction is performed by advancing the spot 331 of the reproduction light beam along the line.

[Explanation of Codes] 11-15 Solid Lines 21-23 Pre-pits 31,231 Spots 41,42,241,242 Overlap 51,251 Semiconductor Lasers 52,252 Collimating Lenses 53a, 53b, 253a, 253b Beam Shaping Prisms 54,264, 268 Beam splitter 55,255 Objective lens 56,256 Optical disk 57,257 Condenser lens 58 Cylindrical lens 59,269,270 Photodetector 211-215 Information track 221-223 Header mark 271 External magnetic field

Claims (2)

[Claims] 1. An optical information recording medium having a plurality of tracks, each of the plurality of tracks being composed of a plurality of sectors, and an area in which header information of each sector is recorded is adjacent between adjacent tracks. The plurality of tracks are set as a plurality of pairs of tracks having two adjacent tracks as one pair, and the polarity of the binary information signal is inverted between the adjacent pairs to form header information. Optical information recording medium. 2. The optical information recording medium according to claim 1, wherein the plurality of tracks are composed of a land portion and a groove portion which are spirally or concentrically formed, and adjacent land portions and groove portions are formed. An optical information recording medium, characterized in that one pair is formed.