Dynamic information storage or retrieval – Storage medium structure – Optical track structure
Reexamination Certificate
1997-09-25
2001-04-10
Edun, Muhammad (Department: 2753)
Dynamic information storage or retrieval
Storage medium structure
Optical track structure
C369S047360, C369S053130, C369S044260
Reexamination Certificate
active
06215758
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a recording medium suitable for recording and reproducing various data, including data for use in computers, and a driving apparatus therefor.
2. Description of the Related Art
It is common practice that various data (application programs, file data, management data, etc.) for use in computer equipment is provided through the use of recording media, such as optical disks, magneto-optic disks, or magnetic disks, and a user stores various data as desired by using these recording media.
For example, as one type of such recording media, a medium called a partial ROM disk has recently been developed. This partial ROM disk is made to have a read-only ROM area and a recordable and reproduceable, rewritable area (RAM area).
There is constantly a demand for larger-capacity recording media. For this reason, high-density recording of data is required. When a disk-shaped recording medium is considered, it is required that the circular track pitch be made narrower.
However, due to various reasons, such as the difficulty in reducing the wavelength of the laser beam in optical heads, the problem of crosstalk caused thereby, and the difficulty of circular tracking control, there is a limitation in making the circular track pitch narrower, and a large capacity is difficult to achieve for practical use.
Further, there has been a demand for a recording and reproduction system to have a higher transfer rate in order to achieve a high-speed recording and reproduction operation when a recording medium is used. In connection with this, the recording medium is required to have a track structure and a data structure suitable for a high transfer rate.
In addition to the structure of what are commonly called read-only ROM disks and recordable RAM disks, when such a structure as that of the above-described partial ROM disk is considered, a format suitable for the integration of what is commonly called read-only pits and lands/grooves formed in a recordable area is in demand.
SUMMARY OF THE INVENTION
In view of such circumstances, the present invention aims to realize a narrower track pitch and a larger capacity while maintaining sufficient practicality. Further objects of the present invention are to realize a higher transfer rate and to realize a format suitable for the integration of read-only pits and lands/grooves formed in a recordable and reproduceable area.
To achieve the above-described goals, according to one aspect of the present invention, there is provided a disk-type recording medium, comprising: a disk-shaped base; a servo area which is provided on the base and in which a plurality of pits for obtaining a servo signal are formed; and a data area which is provided on the base and into and from which information can be recorded and reproduced, wherein one unit area is formed by one the servo area and one the data area, one track is formed of a plurality of the unit areas, and a first track on which the data area is formed on lands and a second track on which the data area is formed on grooves are formed alternately for each track.
According to another aspect of the present invention, there is provided a driving apparatus for driving a disk-type recording medium, comprising: an optical pickup for radiating laser light onto a disk-type recording medium and receiving laser light reflected from the disk-type recording medium, which disk-type recording medium has a servo area in which pits for obtaining a servo signal are formed, and a recordable area into and from which information can be recorded and reproduced, one unit area is formed of the one servo area and the one data area, one track is formed of a plurality of the unit areas, and tracks on which the data area is formed on lands and tracks on which the data area is formed on grooves are formed alternately for each track; rotation driving means for rotating the disk-type recording medium; tracking means for controlling the radiation position of laser light so that the laser light is radiated onto tracks of the disk-type recording medium; servo information generation means for generating servo information in accordance with a servo signal reproduced from the servo area by means of the optical pickup; and control means for controlling the tracking means in accordance with the servo information so that a spot by the laser light scans along the center of the grooves and the center of the lands each time the disk-type recording medium is rotated once.
According to a further aspect of the present invention, there is provided a manufacturing apparatus for manufacturing a disk-type recording medium having a first area formed of one spiral track and a second area formed of two spiral tracks which do not intersect with each other, the manufacturing apparatus comprising: rotation means for rotationally driving the disk-type recording medium; laser means for radiating laser light onto the disk-type recording medium; movement means for moving the radiation position of the laser light in the radial direction of the disk-type recording medium; and control means for switching between a first mode in which pits are formed in the first area by causing the laser means to radiate laser light while the disk-type recording medium is rotated by the rotation means and the laser means is moved in a first direction along the radial direction of the disk-type recording medium at a first velocity by means of the movement means, and a second mode in which pits are formed in the second area by causing the laser means to radiate laser light while the disk-type recording medium is rotated by the rotation means and the laser means is moved in the first direction at a second velocity twice as fast as the first velocity by means of the movement means, and by causing the laser means to move in a second direction opposite to the first direction by a distance equal to the distance at which the laser means was moved at the first velocity during the time in which the disk-type recording medium is rotated half when the disk-type recording medium reaches an angular position determined by the rotation means.
According to still a further aspect of the present invention, there is provided a method of manufacturing a disk-type recording medium having a first area formed of one spiral track and a second area formed of two spiral tracks which do not intersect with each other, the method comprising the steps of: rotationally driving the disk-type recording medium; causing laser means to radiate laser light onto the disk-type recording medium; forming pits in the first area by causing the laser means to radiate laser light while the laser means is moved in a first direction along the radial direction of the disk-type recording medium at a first velocity in a state in which the disk-type recording medium is being rotated; forming pits in the second area by causing the laser means to radiate laser light while the laser means is moved in the first direction at a second velocity twice as fast as the first velocity in a state in which the disk-type recording medium is being rotated; and causing the laser means to move by a distance equal to the distance at which the laser means was moved at the first velocity while the disk-type recording medium is rotated half in a second direction opposite to the first direction when the disk-type recording medium reaches a predetermined angular position while pits are being formed in the second area.
The above and further objects, aspects and novel features of the invention will become more apparent from the following detailed description when read in connection with the accompanying drawings.
REFERENCES:
patent: 4949331 (1990-08-01), Maeda et al.
patent: 5182742 (1993-01-01), Ohmori et al.
patent: 5295130 (1994-03-01), Tobita et al.
patent: 5323373 (1994-06-01), Horimai
patent: 5363352 (1994-11-01), Tobita et al.
patent: 5416766 (1995-05-01), Horimai
patent: 5422874 (1995-06-01), Birukawa et al.
patent: 5448535 (1995-09-01), Fujita et al.
patent: 5469415 (1995-11-01),
Fujita Goro
Horimai Hideyoshi
Tobita Minoru
Tosaka Susumu
Edun Muhammad
Limbach & Limbach L.L.P.
Oh Seong-Kun
Sony Corporation
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