JPH05159376A - Optical information recording medium - Google Patents

Abstract

PURPOSE:To obtain an extremely accurate position for recording address information upon recording the address information by forming an area where light quantity reflected from a scanning light spot becomes singular in an address area. CONSTITUTION:The recording medium is irradiated with a light spot 10 and while controlling so as to maintain the center of this light spot between two adjacent groups 5, the irradiation with this light spot 10 is executed. Scanning is made by moving the light spot towards the direction of the arrow against the recording medium along the group 5, while controlling so as to keep the center of the light spot to stay adjacent to the two groups 5 which are on adjacent relation. In an area 9 where the address information is required, the reflected light quantity detected from reflection from this light spot to the optical head increases when the light spot 10 reaches the group discontinuing point 6. By using this increase of the light quantity as a trigger signal for recording the address information, the address information 7 is recorded from the position taken immediately thereafter in order to improve the accuracy of the position for recording the information 7.

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 for recording / reproducing information using laser light or the like.

[0002]

2. Description of the Related Art FIG. 7 shows a plan view of a disc-shaped optical information recording medium. 8 and 9 respectively show X- of FIG.
It is a Y sectional view and an X'-Y sectional view. In the recording / reproducing area of the recording medium substrate, as shown in FIG. 7, guide grooves (grooves) 11 are formed in a spiral shape or a concentric shape. The groove is for controlling the light spot formed by the laser beam convergently irradiated from the optical head of the recording / reproducing apparatus to follow a desired track. An address area 12 for recording address information indicating a position on the medium is radially formed in a recording / reproducing area of the recording medium, and a data area 13 for recording data information is provided between these address areas. Has been formed. Conventionally, pits 14 are formed as address information in the address area 12 as shown in FIG.
Such a substrate can be obtained by using a metal member (stamper) having a shape corresponding to the groove and the pit on the surface and injection molding a thermoplastic resin to transfer the surface shape of the stamper.

However, the pit 1 formed on the substrate
The depth of 4 is usually about 1000 to 1600Å, and the depth of the groove 11 formed on the substrate is 600 to 800.
It is about Å, and the pit 14 is deeper than the groove 11. Therefore, when the substrate, which is a molded product, is released from the stamper after injection molding, the releasability differs between the pit and the groove, and the shape of the pit is more likely to collapse than the shape of the groove. Was difficult.

Therefore, the same method as that for recording data information in a data area (such as a magneto-optical recording method) is used as a substrate of an optical information recording medium, in which only grooves are formed and no pits are formed. A method (soft format method) of recording address information in an address area by using the method is being studied.

[0005]

By the way, when recording address information in the address area of the optical information recording medium for the soft format method, it is desirable to accurately determine the recording position of the address information. , Traditionally,
A recording medium having means for determining the recording position of the address information with high accuracy has not been provided, and there has been a problem that the positioning accuracy of the recording position is not sufficient.

An object of the present invention is to improve the accuracy of the recording position of address information when recording address information on a soft format optical information recording medium.

[0007]

According to the present invention, in order to achieve the above-mentioned object, an optical information recording method for scanning address spots in an address area by scanning a light spot in the same manner as data information is recorded. There is provided an optical information recording medium, characterized in that a portion of the medium having a specific amount of reflected light from a scanning light spot is formed in an address area.

In the present invention, the guide groove is formed in the address area so as to be continuous with the data area, and the portion where the amount of reflected light from the scanning light spot is unique is the discontinuous portion of the guide groove. , There are modes.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 4 shows a first example of the optical information recording medium of the present invention.
FIG. 1 is a plan view showing an embodiment of the present invention, FIG. 1 is a partially enlarged view thereof, and FIGS. 2 and 3 are AB sectional views and C thereof, respectively.
It is a -D sectional view.

In these figures, 1 is a disk-shaped magneto-optical recording medium, 2 is an address area, and 3 is a data area. In FIG. 4, reference numeral 4 indicates an area enlarged in FIG. 5 is a groove, and the groove is formed in a substantially spiral shape. As shown in FIG. 1, in the address area 2, a groove 5 is continuously formed in a portion 8 where address information is unnecessary,
Grooves 5 are discontinuously formed in a portion 9 where address information is required. The discontinuous portion of this groove 5 is designated by 6. Reference numeral 7 is address information recorded by the magneto-optical recording method.

A process of recording address information when manufacturing the above recording medium will be described with reference to FIG. An optical head (not shown) irradiates a recording medium with a light spot 10, and the center of the light spot is adjacent to the recording medium 2.
The scanning is performed by moving the light spot along the groove 5 in the direction of the arrow relative to the recording medium while performing control to maintain the space between the two grooves 5. In the portion 9 where address information is required, when the light spot 10 reaches the groove discontinuous portion 6, the amount of reflected light that is detected by returning from the light spot to the optical head increases. FIG. 5 shows how the reflected light amount changes with respect to this light spot position, and it can be seen that the groove discontinuous portion 6 corresponds to the reflected light amount peculiar portion (reflected light amount increasing portion). This increase in light amount is used as a trigger signal for recording address information, and the address information 7 is recorded from the position immediately after that.
By doing so, the accuracy of the recording position of the address information can be sufficiently enhanced.

FIG. 6 shows a second example of the optical information recording medium of the present invention.
FIG. 6 is a partially enlarged plan view of the embodiment of FIG. In the present embodiment, the groove discontinuous portions 6 are not present as one along the groove 5 but are intermittently present in plural. By appropriately determining the pattern, the detection of the pattern can be used as a trigger signal. By doing so, it is possible to sufficiently prevent erroneous recording of address information based on erroneous detection.

In the above embodiment, the optical information recording medium has a disk shape, but the present invention can also be applied to optical information recording media other than the disk shape. The present invention can also be applied to an optical information recording medium of a system other than the magneto-optical recording / reproducing system.

[0015]

As described above, according to the present invention,
In the optical information recording medium that scans the light spot by the same method as the recording of the data information to record the address information in the address area, a portion where the reflected light amount from the scanning light spot is unique is formed in the address area. When recording information, the recording position of the information can be made extremely accurate.

[Brief description of drawings]

FIG. 1 is a partially enlarged plan view showing a first embodiment of an optical information recording medium of the present invention.

FIG. 2 is a cross-sectional view taken along the line AB of FIG.

FIG. 3 is a sectional view taken along line C-D in FIG.

FIG. 4 is a plan view showing a first embodiment of the optical information recording medium of the present invention.

FIG. 5 is an explanatory diagram of an address information recording process when manufacturing the first embodiment of the optical information recording medium of the present invention.

FIG. 6 is a partially enlarged plan view of the second embodiment of the optical information recording medium of the present invention.

FIG. 7 is a plan view of a disc-shaped optical information recording medium.

8 is a cross-sectional view taken along line XY of FIG.

9 is a cross-sectional view taken along the line X'-Y of FIG.

[Explanation of symbols]

 1 Magneto-optical recording medium 2 Address area 3 Data area 5 Groove 6 Groove discontinuity 7 Address information 10 Optical spot

Claims (2)

[Claims] 1. An optical information recording medium in which an address spot is recorded by scanning a light spot in the same manner as the recording of data information, and a portion where an amount of reflected light from the scanning light spot is peculiar to the address region An optical information recording medium characterized by being formed. 2. A guide groove continuous with the data area is formed in the address area, and a portion where the amount of reflected light from the scanning light spot is unique is a discontinuous portion of the guide groove. 1. The optical information recording medium described in 1.