JP2583556B2 - Information recording / reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording / reproducing apparatus for recording and / or reproducing and / or erasing information by irradiating an information recording medium with a light beam.

[Conventional technology]

A magneto-optical disk is formed by forming a magnetic thin film having an easy axis of magnetization perpendicular to the film surface on a substrate, and records information by changing the magnetization direction of the magnetic thin film. At the time of recording, the magnetization direction of the magnetic thin film is first aligned in one direction in advance, and a laser beam digitally modulated according to an information signal is applied to this while applying a bias magnetic field in a direction opposite to the magnetization direction. Then, the temperature of the portion irradiated with the laser beam rises to the vicinity of the Curie point, the coercive force decreases, and the portion is magnetized in the direction opposite to the surroundings by the influence of the bias magnetic field, thereby forming a magnetization pattern according to the information. By irradiating the medium with a low-output unmodulated beam, the information thus recorded can be read out optically using the well-known magneto-optical effect. Further, by applying a magnetic field in a direction opposite to the bias magnetic field at the time of recording, the recorded information can be erased.

In such an information recording / reproducing device such as a magneto-optical disk device, the laser power at the time of recording or erasing needs to be about several times to about ten times the laser power at the time of reproduction. When the laser power at the time of this reproduction is turned on, the laser power is turned on without any special care because the set value of the laser power is the reproduction power.

[Problems to be solved by the invention]

However, in the conventional information recording / reproducing apparatus as described above, even if the set value of the laser power is set to the power mode at the time of recording or erasing due to an external instruction or a failure of a circuit in the apparatus, it is unconditional. Since the laser is turned on, there is a problem that information on the medium may be destroyed in some cases.

〔Purpose〕

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the related art, and has as its object when the laser power instruction is in a recording or erasing mode or when a circuit failure in the apparatus occurs. Another object of the present invention is to provide an information recording / reproducing apparatus which does not cause destruction of information recorded on an information recording medium by turning on a laser.

[Means for solving the problem]

According to the present invention, there is provided an information recording / reproducing apparatus which performs at least one of information recording, reproducing, and erasing by irradiating a recording medium with a laser beam. A light source for generating light; a laser driving circuit for driving the light source such that laser light of a desired intensity is generated from the light source during each of recording, reproducing, and erasing operations; and the recording, reproducing, and erasing operations. Control means for issuing a lighting command to the laser drive circuit to turn on the laser light prior to lighting, the control means, when issuing a lighting command to the laser drive circuit, the laser When a recording or erasing command is issued to the drive circuit, a process for inhibiting the operation of turning on the laser light is performed. Information recording and reproducing apparatus which, is provided.

[Example] Hereinafter, an example according to the present invention will be described specifically and in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing a laser control unit of the information recording / reproducing apparatus of the present invention.

In FIG. 1, reference numeral 1 denotes a laser for recording, reproducing, and erasing information. Reference numeral 2 denotes a laser drive circuit for turning on the laser 1. Reference numeral 3 denotes a CPU that controls the laser drive circuit 2.

Reference numeral 4 denotes a laser drive signal indicating a signal sent from the laser drive circuit 2 to the laser 1 to turn on the laser. Reference numeral 5 denotes a laser lighting signal which is sent from the CPU 3 to the laser driving circuit 2 and indicates a signal for controlling the timing at which the laser 1 is turned on. Reference numeral 6 denotes a recording instruction signal indicating a signal for turning on the laser 1 with a power necessary for recording information on an information recording medium (not shown). Similarly, reference numeral 7 denotes an erasure instruction signal indicating a signal for turning on the laser 1 with a power necessary to erase information from an information recording medium (not shown).

Next, the operation of the information recording / reproducing apparatus of the present invention will be described in the second.
This is performed using the figure.

FIG. 2 is a flowchart for explaining the operation of the laser control section of the information recording / reproducing apparatus of the present invention.

In step 1 of FIG. 2, it is determined whether or not there is an instruction to turn on the laser 1. If there is no instruction to turn on the laser 1 (NO in FIG. 2), the processing of the flowchart is completed as shown in FIG. move on. When there is an instruction to turn on laser 1 (YE in the figure)
In S), go to the next step 2.

In step 2, it is determined whether or not the recording instruction signal 6 for turning on the laser 1 at the power at the time of recording is in the access state, and when it is determined that the recording instruction signal 6 is in the access state (YES ), Go to step 5. If the recording instruction signal 6 is not in the access state (NO), the process proceeds to the next step 3.

In step 3, it is determined whether or not the erase instruction signal 7 for lighting the laser 1 at the power at the time of erase is in an access state. When it is determined that the erase instruction signal 7 is in an access state (YES) ), Go to step 5. If the erase instruction signal 7 is not in the access state (NO), the process proceeds to the next step 4.

In step 4, the laser 1 is used at a reproduction power that is smaller than the power at the time of recording or the power at the time of erasing.
Lights up. Then, the process of the flowchart is advanced to the end as illustrated.

In step 5, a process of ignoring an instruction to turn on the laser 1 (recording instruction signal 6 and erasing instruction signal 7), that is, a process of prohibiting lighting with recording power or erasing power is performed (error in step 5). Then, the process of the flowchart ends.

〔The invention's effect〕

As described above, the information recording / reproducing apparatus of the present invention confirms whether or not a recording or erasing command has been issued to the laser drive circuit when performing a laser lighting operation by the laser drive circuit. Alternatively, when an erasing command is issued, the operation of turning on the laser light is prohibited, so the strong laser light is turned on by mistake during the operation of turning on the laser light, and the information recorded on the information recording medium is mistakenly turned on. It is possible to prevent erasure or accidental overwriting.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a laser control unit of the information recording / reproducing apparatus of the present invention, and FIG. 2 is a flowchart for explaining the operation of the information recording / reproducing apparatus of the present invention. 1 ... Laser, 2 ... Laser drive circuit, 3 ... CP
U, 6... A recording instruction signal, 7... An erasure instruction signal.

Claims (1)

(57) [Claims] 1. An information recording / reproducing apparatus which performs at least one of recording, reproducing and erasing of information by irradiating a recording medium with a laser beam, comprising: a light source for generating the laser beam; A laser driving circuit for driving the light source such that a laser beam of a desired intensity is generated from the light source during each operation of the light source, and the recording, reproducing, and erasing the laser light prior to the erasing operation. Control means for issuing a lighting command to the laser drive rotation, when the control means issues a lighting command to the laser drive circuit, a recording or erasing command is issued to the laser drive circuit. An information recording / reproducing apparatus for performing a process of prohibiting an operation of turning on the laser light when the information is recorded.