JPH0240145A - Method for initializing reloadable optical recording medium - Google Patents

Abstract

PURPOSE:To initialize the whole of a recording film in a short time by irradiating a recording film by an energy beam by converging linearly, and moving the recording film relatively in a direction perpendicular to that of the linear energy beam. CONSTITUTION:At the time of performing the initialization of an optical recording medium 2 which records information by irradiating the information by the energy beam and changing the physical property of the optical constant or the magnetizing direction of an irradiation part, etc., and also, performs the erasure of the information by recovering the physical property of the irradiation part to its original one by irradiating the irradiation part again by the energy beam, the recording film is irradiated by the energy beam 10 by converging linearly. Simultaneously, the recording film is moved relatively in the direction perpendicular to that of the energy beam 10 converged linearly, and the physical property of the recording film is kept constant along a film plane. In such a way, it is possible to initialize the optical recording medium in a quite short time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for initializing an optical recording medium having a recording film on which information can be rewritten.

The following two types of optical recording media are currently known as typical optical recording media having a recording film on which information on t and 2 can be rewritten. That is, they are a phase change type optical recording medium and a magneto-optical type optical recording medium.

Phase-change optical recording media change the optical constants of this area by irradiating the recording film with an energy beam such as a laser beam and changing the recording film in the irradiated area from a crystalline phase to an amorphous phase or vice versa. It is now possible to record and erase information by changing the

In addition, magneto-optical optical recording media change the magnetization direction of the recording film in the irradiated area by irradiating an energy beam onto the recording film, which can be magnetized in a direction perpendicular to the film surface. This allows information to be recorded and erased.

Regardless of the type of optical recording medium, before it is shipped as a product, it is necessary that no information is recorded on the recording film of this optical recording medium, so it is necessary to initialize it. There is.

The conventional method for initializing this information is
While irradiating the surface of the recording film of the recording medium with an energy beam such as a laser beam in spots, the energy beam and the recording film are moved relative to each other, and as a result, the entire surface of the recording film is irradiated with this energy beam. However, a method is known in which initialization is performed by making the physical properties of the recording film, such as the optical constants or the magnetization direction, constant along the film surface.

However, in such a conventional initialization method, since the energy beam is irradiated onto the recording film in spots, it takes time to initialize the entire recording film, which is a bottleneck in the work process.

The present invention has been made in order to eliminate the inconveniences of the prior art, and aims to provide an initialization method that can initialize a rewritable optical recording medium in an extremely short time. shall be.

In order to achieve such an objective, the initialization method according to the present invention changes the physical properties such as the optical constants or magnetization direction of the irradiated part by irradiating it with an energy beam, thereby transmitting information. In a method for initializing a rewritable optical recording medium having a recording film capable of recording and erasing information by restoring the physical properties of the irradiated part to its original state by irradiating the irradiated part with an energy beam again, The recording film is irradiated with a linearly focused energy beam, and the recording film is moved relative to the linearly focused energy beam in a direction perpendicular to the linearly focused energy beam to determine the physical properties of the recording film. It is characterized by being constant along the membrane surface.

According to such an initialization method according to the present invention, an energy beam is focused linearly and irradiated onto the recording film, and the recording film is moved relative to the direction perpendicular to the linear energy beam. Therefore, the initialization of the entire recording film is completed during this relative movement, making it possible to complete the initialization in an extremely short time.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail based on embodiments shown in the drawings.

FIG. 1 is a perspective view of a main part showing a specific example of an initialization method according to an embodiment of the present invention.

An embodiment of the present invention shown in FIG. 1 shows a case where a magneto-optical optical recording medium in which information can be rewritten is initialized by the method of the present invention. As shown in the figure, a magneto-optical optical recording medium 2 on which a recording film before initialization has been formed is placed on a belt 4 and conveyed in six directions of arrows. At a position above the belt 4, a cylindrical energy beam generating means 6 that emits an energy beam (for example, infrared rays) is provided.
are arranged so as to extend in a direction perpendicular to the traveling direction A of the belt 4. This energy beam generating means 6
The axial length of is preferably larger than the diameter of the optical recording medium 2. Specifically, an infrared lamp, an electric heater, a halogen lamp, a tungsten lamp, a dye laser, a mercury lamp, a semiconductor laser, a gas laser, etc. are used as the energy beam generating means.

A concave reflecting mirror 8 is arranged above the energy beam generating means 6, and directs the energy beam emitted from the energy beam generating means 6 onto the film surface of the recording film formed on the optical recording medium 2. It focuses the energy beam into a line.

The energy amount of the energy beam emitted from the energy beam generating means 6 is uniformly unidirectionally generated by the magnetic force generating means because the temperature of the recording film in the area irradiated with the linearly focused energy beam 10 weakens at that temperature. The temperature is determined to be equal to or higher than that of the

In this embodiment, in order to initialize the optical recording medium 2,
A magnetic force generating means 12 is arranged at a position directly below the belt 4 corresponding to the linearly focused energy beam 10. The magnetic force generating means 12 applies a uniform external magnetic force to the recording film whose coercive force has been weakened by being heated by being irradiated with the linear energy beam 10, so that the magnetization direction is all the same. . Therefore, the direction of the magnetic force generated by the magnetic force generating means 12 through the recording film is as follows:
It is necessary to be perpendicular to the film surface of the recording medium.

In order to initialize the optical recording media 2 using such a device, the optical recording media 2 before initialization are placed one after another on the belt 4, the optical recording media 2 are conveyed by the belt 4, It is sufficient that the energy beam is passed directly below the energy beam generating means 6.

Then, the linearly focused energy beam 10 is irradiated over the entire area of the recording film of the magneto-optical optical recording medium 2 as the belt 4 moves, and the temperature of the recording film is raised one after another to a temperature higher than the Curie temperature. Then, by weakening the coercive force and applying magnetic force in the same direction to that portion, the recording film is magnetized perpendicularly in the same direction and initialized.

Note that the present invention is not limited to the embodiments described above, and can be variously modified within the scope of the present invention.

For example, according to the method of the present invention, a phase change optical recording medium,
Alternatively, other types of optical recording media can also be initialized. For this purpose, it is not necessarily necessary to provide the magnetic force generating means 12 at a position directly below the belt 4 corresponding to the linear energy beam 10. This is because it is not necessary to perform magnetization in the same direction for initialization. However, in order to initialize a phase change type optical recording medium, the temperature conditions of the recording film irradiated by the linear energy beam 10 must be such that the temperature rise and cooling rate necessary for phase change are achieved. In addition, it is necessary to adjust the energy emitted by the energy beam generating means 6 and the conveyance speed of the belt 4.

Further, the shape of the focused energy beam 10 may be substantially linear, and in this specification, the term "linear" includes all shapes elongated in the longitudinal direction. The means for linearly converging the energy beam emitted by the energy beam generating means 6 is not limited to the concave reflecting mirror 8, but a convex lens, a cylindrical lens, etc. may be used.

Further, the shape of the energy beam generating means 6 is not limited to a cylindrical shape, but may be a polygonal column, a sphere, a donut shape, a disk shape, or the like.

Furthermore, the optical recording medium 2 is exposed to the linear energy beam 1.
The means for relatively moving in the direction perpendicular to 0 is not limited to the belt conveyor 4, but may be other conveying means such as a chain, an air syringe, or a robot arm. Furthermore, the generating means 6 may be moved relatively without moving the optical recording medium 2.

As explained above, according to the present invention, an energy beam is focused linearly, irradiated onto a recording film, and the recording film is moved relative to the direction perpendicular to the linear energy beam. Therefore, the initialization of the entire recording film is completed during this relative movement, making it possible to complete the initialization in an extremely short time.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a main part showing a specific example of an initialization method according to an embodiment of the present invention. 2... Optical recording medium 4... Belt 6...
Energy beam generating means 10...Energy beam

Claims (1)

[Claims] 1) Information is recorded by changing the physical properties such as the optical constant or magnetization direction of the irradiated part by irradiating the irradiated part with an energy beam, and by irradiating the irradiated part with the energy beam again. In a method for initializing a rewritable optical recording medium having a recording film capable of erasing information by restoring the physical properties of an irradiated part to its original state, the recording film is irradiated with a linearly focused energy beam, and , a rewritable recording film characterized in that the recording film is moved relative to the linearly focused energy beam in a direction perpendicular to the linearly focused energy beam, and the physical properties of the recording film are made constant along the film surface. How to initialize an optical recording medium. 2) The recording film is a magneto-optical recording film that can be magnetized in the direction perpendicular to the film surface, and is opposite to the recording film on the side to which the linearly focused energy beam is irradiated. The recording film is irradiated with an energy beam from a side position.
2. The method for initializing a rewritable optical recording medium according to claim 1, wherein a magnetic force perpendicular to the film surface is applied.