JPH1186286A - Optical disc inspecting instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable detection of both of obstacles, one which decreases the quantity of reflected light and the other which increases it over the entire recording area in the diametrical direction of an optical disc. SOLUTION: An optical head 4 is displaced over the entire recording area in the diametrical direction of an optical disc during the inspection of the optical disc. The obstacle of the optical disc is judged by a disc obstacle judging means 22 even when a detection output from a quantity of reflected light detection circuit 9 is deviated, low or high, from a normal level range that enables the judging of the optical disc to be normal. As a result, both obstacles, one which decreases the quantity of reflected light and the other which increases it, are detected over the entire recording area of the optical disc. In this case, the location of the obstacle judged to obstruct is detected using a detection output from a displacement value detection circuit 12, thereby enabling learning of the position of a disc where the obstacle location exists.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk inspection apparatus for detecting an amount of light reflected by an optical disk from a light beam emitted from an optical head and detecting an obstacle such as a scratch or dirt on the optical disk. The present invention relates to an optical disk inspection device suitable for inspecting an optical disk for a failure in order to prevent a recording failure due to a failure.

[0002]

2. Description of the Related Art In an optical disk recording apparatus that performs recording on an optical disk using a light beam emitted from an optical head, a disk failure such as a scratch or dirt on the optical disk is directly related to the reliability of recording, and a disk failure is recorded. Is a major cause of failure.

For this reason, it is preferable that a recording optical disk on which recording is performed by an optical disk recording apparatus detect a failure such as a scratch or dirt in advance. As an optical disk inspection device that detects a failure of a recording optical disk, an optical disk inspection device that irradiates an optical disk with a light beam emitted from an optical head and detects the amount of light reflected by the optical disk to detect an optical disk failure is known. Have been.

[0004]

The above-mentioned optical disk inspection apparatus is disclosed, for example, in Japanese Patent Laid-Open No. 5-159507. Was not detected, and the range in which recording could not be performed when the optical disk had a failure could not be determined.

[0005] Further, even if a failure of the optical disk is detected, if the failure is stained, the optical disk can be cleaned to remove the stain and return to a normal state in which recording can be performed. Although the meaning is greatly different between the optical disk and the optical disk due to dirt, no distinction is made between the damage and the optical disk, and the optical disk must be directly visually confirmed.

Although the amount of reflected light may increase depending on the scratch, the conventional optical disk inspection apparatus detects only a decrease in the amount of reflected light and detects a failure in the optical disk. The failure of the optical disk due to the increasing scratches could not be detected.

An object of the present invention is to solve the above-mentioned points.

[0008]

According to the present invention, the optical head is displaced over the entire recording area in the radial direction of the optical disk at the time of inspection of the optical disk, and the detection output from the reflected light amount detection circuit corrects the optical disk. An optical disk failure is determined regardless of whether it is out of the normal level range, which is a criterion for judging the state, either a low level or a high level, and the amount of reflected light over the entire recording area in the radial direction of the optical disk. Both the obstacle in which the light amount decreases and the obstacle in which the amount of reflected light increases are determined.

In addition, a failure of the optical disk is determined based on a detection output from the reflected light amount detection circuit, and a failure point determined as the failure is detected using a detection output from the displacement amount detection circuit. The position of the disk where the portion exists is known so that the range where recording cannot be performed can be known.

In this case, if the failure of the optical disk is stained by the distribution of the disk position where the failure point is detected, the fact is displayed so that the disk position from which the stain is to be removed can be easily recognized. .

[0011]

1 is a circuit block diagram showing an embodiment of an optical disk inspection apparatus according to the present invention. The optical disk inspection apparatus shown in FIG. 1 includes a personal computer A and a CD-R drive B connected as an external storage device. It consists of.

In FIG. 1, 1 is a CD-R disc, 2
Reference numeral 3 denotes a spindle motor for rotating and driving the disk 1, and 3 a spindle servo circuit for controlling the drive of the spindle motor 2.

An optical head 4 emits a laser beam for irradiating the disk 1, and has an optical detector (not shown) for receiving a reflected beam reflected by the disk 1. A reference numeral 5 denotes a laser beam for irradiating the disk 1. Focusing control and tracking control are performed, and the feed motor 6 is controlled.
Is a head servo circuit for performing thread feed control for sending the optical head 4 itself in the radial direction of the disk 1, and a servo control circuit 7 for controlling the spindle servo circuit 3 and the head servo circuit 5.

Reference numeral 8 denotes a main signal output by adding the respective light receiving outputs obtained from specific light receiving elements constituting the light detector so as to generate an RF signal which is a recording signal of the disk 1 from the light detector of the optical head 4. The generated RF signal generation circuit 9 is a reflected light amount detection circuit that detects the level of the main signal output generated by the RF signal generation circuit 8 and detects the reflected light amount of the disk 1.

The main signal output generated by the RF signal generation circuit 8 is supplied to the reflected light amount detection circuit 9 and also to a main signal processing circuit for binarizing the RF signal and decoding the digital data. Supplied.

Reference numeral 10 denotes a sensor for generating a detection output accompanying rotation of the feed motor 6, and reference numeral 11 denotes a disk 1 of the optical head 4.
A switch 12 for detecting an initial set position on the innermost peripheral side of the optical disk 1. A switch 12 detects the amount of displacement of the optical head 4 in the radial direction of the disk 1 based on the detection output of the sensor 10 based on the position where the switch 11 is switched. A displacement detection circuit 13 for generating a detection output from the reflected light detection circuit 9 and a detection output from the displacement detection circuit 12 as digital data that can be interpreted by a personal computer A serving as a host, which will be described later; This is an interface for matching with the personal computer A.

A connection terminal 1 is connected to the personal computer A serving as a host.
6 is provided with a command generating means 17 for generating a command requesting an external storage device connected to 6 and an interface 18 for matching with the external storage device.

The command generating means 17 is provided on the disk 1
, A command for setting each inspection condition of a detection timing of the reflected light amount detection circuit 9 and the displacement amount detection circuit 12 and a thread feed speed of the disk 1 by the optical head 4 are generated. The input means 20 such as a keyboard, which is set by the setting means 19
Can be changed arbitrarily.

Also, the personal computer A has reflected light amount information of a detection output obtained by the reflected light amount detecting circuit 9 from digital data generated by the data forming circuit 13 and a detection output obtained by the displacement amount detecting circuit 12. Extracting means 21 for extracting the disc position information of the disc as reflected light quantity data and position data, respectively, and the data extracting means 2
A disk failure determination unit 22 for determining a failure of the disk 1 from the reflected light amount data extracted by the disk unit 1, the position data extracted by the data extraction unit 21, and the disk 1
Position detecting means 23 for detecting a disk position in consideration of the rotational speed at which the disk is driven;
And a display control means 24 for controlling a display 25 connected to the personal computer A according to the judgment output by the position detection means 23 and the disk position detection output by the position detection means 23.

The position detecting means 23 detects the disk position in the radial direction of the disk 1 which has received the reflected light amount data from which the disk failure determining means 22 determines the disk failure based on the input position data. The rotational speed at which the disk drive 1 is driven is calculated, and the disk position in the rotational direction of the disk 1 from which the reflected light amount data is captured is detected from the rotational speed.

The disk failure determining means 22 sets reference light level data in advance as an average level of a normal level range of the reflected light amount for determining that the disk 1 is in a normal state, and inputs the reflected light amount data to the reference light level data. Then, a failure of the disk 1 is determined by detecting that the level difference based on the comparison is out of the normal level range of the amount of reflected light in which the disk 1 can be determined to be in a normal state.
Then, the disk failure determining means 22 takes in the disk position data detected by the position detecting means 23, detects the disk position at the time of determining that a failure has occurred, and specifies the failure location.

Reference numeral 27 denotes a command interpreting circuit for interpreting a command generated from the personal computer A, and reference numeral 28 controls an access operation for displacing the trace position of the disk by the optical head 4 in accordance with the command interpreted by the command interpreting circuit 27. Access control circuit.

In the optical disk inspection apparatus configured as described above, when inspecting a disk for failure, the disk to be inspected is mounted on the CD-R drive B, and the personal computer A is set with various measurement conditions at the time of the inspection, and the inspection is performed. Give instructions to start.

The measurement conditions at the time of inspection set in the personal computer A include the rotational speed for driving the disk 1 using the input means 20, the detection timing by the reflected light amount detection circuit 9 and the displacement amount detection circuit 12, and the optical head 4 The thread feed speed is selected from several preset options and set in the setting unit 19.

When each inspection condition is not set using the input means 20, each inspection condition set as a standard setting is automatically selected, and the standard setting is set in the setting means 19. .

When an instruction to start the disk inspection is given, a command for executing the disk inspection including the inspection conditions set in the setting unit 19 is issued to the command generation unit 17.
And the command is supplied to the CD-R drive B via the interface 18 and the interface 1
4 to the command interpreting circuit 27.

When a command is supplied to the command interpreting means 27 and the command is interpreted by the command interpreting means 27, the rotation speed of the disk 1 is reduced by the control of the spindle servo circuit 3 by the servo control circuit 7 in accordance with the interpretation. The detection timing by the reflected light amount detection circuit 9 and the displacement amount detection circuit 12 is set, and the disk 1 by the optical head 4 is controlled by the access control circuit 28.
Is set, and the inspection of the disk is started.

At the time of inspection of the disk, the optical head 4
In this case, the focus servo is turned on and the tracking servo is turned off, and the disk 1 is traced.
In this case, thread feed control is performed at a thread feed speed according to the above-described command interpretation, and the thread feed control is performed over the entire recording area in the radial direction of the disk 1.

When the disk 1 is traced by the optical head 4, the reflected light reflected by the disk 1 is received by the photodetector of the optical head 4, so that the RF signal generating circuit 8 generates a main signal output, The reflected light amount detection circuit 9 detects the level of the main signal output.

On the other hand, when the optical head 4 is thread-fed, a pulse output generated from the sensor 10 in response to the rotation of the feed motor 6 is supplied to a displacement detection circuit 12, and the displacement detection circuit 12 The pulse output from the sensor 10 is counted to generate a count output indicating the disk position of the optical head 4 in the disk radial direction.

The timing at which level detection is performed by the reflected light amount detection circuit 9 and the timing at which the count output is generated by the displacement amount detection circuit 12 are determined by the command interpretation circuit 2.
The detection output, which is set for each specific designated time required by the command supplied to the command 7 and is detected by the reflected light amount detection circuit 9 and the count output generated by the displacement amount detection circuit 12, is sent to the data creation circuit 13 respectively. Supplied.

The data generating circuit 13 converts the detection output detected by the reflected light amount detecting circuit 9 into reflected light amount data indicating reflected light amount information, and converts the count output generated by the displacement amount detecting circuit 12 into the disk position. Digital data including the reflected light amount data and the position data is created as position data indicating information. The digital data is supplied to the personal computer A via the interface 14.

The digital data supplied to the personal computer A is supplied to the data extracting means 21 via the interface 18, and the data extracting means 21 extracts reflected light amount data and position data from the digital data.

The reflected light quantity data extracted by the data extracting means 21 is compared with the reference light quantity level data by the disk failure determining means 22, and the disk failure determining means 2
2 detects that the disk 1 is out of the normal level range of the amount of reflected light in which the disc 1 can be judged to be in a normal state by judging a failure of the disc 1.

On the other hand, the position data extracted by the data extracting means 21 is used for detecting the disk position by the position detecting means 23, and the position detecting means 23 uses the input position data to detect the disk failure judging means 22. The disk position is detected in the radial direction of the disk 1 from which the reflected light amount data for which the determination of the disk failure is made is taken, and the rotational speed is taken into consideration in consideration of the set rotational speed from the set rotational speed at which the disk 1 is driven. The disk position in the rotation direction of the disk 1 that has received the reflected light amount data is detected.

The disk position data detected by the position detecting means 23 is taken into the disk fault judging means 22, and the disk position at the time of judging the fault is detected to specify the fault location.

Incidentally, the disk failure determination means 22
The timing at which the reflected light amount data at which the disc failure is determined is determined by the reflected light amount detection circuit 9 and the displacement amount detection circuit 12 set by the setting means 19, and the detection timing set by the setting means 19 In response to this, a command for measuring the failure of the disk 1 is generated from the command generation means 17.

The disk position corresponding to the count output generated by the displacement amount detection circuit 12 which is the basis of the position data input to the position detection means 23 is set to the rotation for driving the disk 1 set by the setting means 19. It is determined by the speed and the thread feed speed by the optical head 4.

Therefore, the disk position at the time when the disk failure determination means 22 determines that a failure has occurred is determined by the reflected light amount detection circuit 9 set by the setting means 19.
The measurement interval for measuring the failure of the disk 1 changes depending on the detection timing of the displacement amount detection circuit 12, the rotational speed for driving the disk 1, and the thread feed speed of the optical head 4.

If the measurement interval is made closer, the measurement time becomes longer, but precise measurement becomes possible. On the other hand, if the measurement interval is made coarser, the measurement time is reduced although the measurement accuracy is reduced. Each measurement condition set in the setting means 19 is selected according to the situation.

The output of the judgment by the disk failure judging means 22 is inputted to the display control means 24, and a display expressing the judgment output by the disk failure judging means 22 is displayed on the display 25.

As shown in FIG. 2, for example, a graphic 29 representing a disk is displayed on the display 25, and the disk position at the time when the disk failure determination means 22 determines that a failure has occurred, that is, the failure location is displayed on the graphic 29. Is drawn at the corresponding position.

The display 25 has a display area 30 for displaying numerical data indicating the level difference between the reflected light amount and the normal level range when the disk failure determination means 22 determines that a failure has occurred, in addition to the graphic 29. Is provided, and a display that is useful for estimating the degree of the failure is provided.

Incidentally, the disk failure determination means 22
Determines the failure of the disk 1 regardless of whether it is out of the normal level range for determining the disk to be in the normal state, either low or high, so that the amount of reflected light decreases. It is possible to judge both obstacles of the wound where the amount of light increases, and in this case, since the amount of reflected light is unlikely to increase at the obstacle due to dirt,
If the level deviates from the normal level range at a high level, it is determined to be a flaw.

Further, the disk failure determination means 22 has detected which disk position has a failure determined to be a failure of the disk 1. However, the disk failure determination means 22 deviates from the normal level range at a lower level. If there is a failure, the distribution of disk positions where the failure location is detected is determined, and it is determined whether the detected failure of the disk 1 is dirty or scratched.

In this case, since the obstacle due to the scratch is often a linear distribution, if it is determined that such a distribution is present, it is determined that the obstacle is a scratch. In most cases, the distribution is often spread to an adjacent position. Therefore, when it is determined that the distribution is such, it is determined that the surface is dirty.

If the disk failure determining means 22 determines that the failure of the disk 1 is dirty, the display control means 24 changes the display on the display 25 to display the dirty state. If it is determined that the image is a flaw, the display control means 24 changes the display on the display 25 to a display representing the flaw.

That is, on the display 25, a display 31 representing dirt and a display 32 representing flaws are displayed in different colors and densities. Therefore,
The position of the disk 1 where the failure location of the disk 1 is located can be seen at a glance from the display on the display 25, and it can be determined whether the failure is due to a scratch or dirt. For that reason,
In addition to knowing the position of the disk on which recording cannot be performed, if the obstacle is due to dirt, the position of the disk from which dirt should be removed can be easily recognized.

It is also possible to express the degree of failure by classifying into several levels according to the level difference that is out of the normal level range. By the way, when the disk is inspected, the tracking servo is turned off to displace the optical head 4 by thread feed over the entire recording area in the radial direction of the disk 1, so that there is a portion where tracking cannot be performed on the disk due to a disk failure. However, the optical head 4
Of the optical head 4 over the entire recording area of the disk 1 regardless of the disk failure.
Can be traced.

[0050]

As described above, according to the present invention, when inspecting an optical disk, the optical head is displaced over the entire recording area in the radial direction of the optical disk, and the detection output from the reflected light amount detection circuit is used to detect the optical disk. Even if the level is out of the normal level range, which is the criterion for determining the normal state, either the low level or the high level, the failure of the optical disk is determined, so that the entire recording area in the radial direction of the optical disk is determined. It is possible to detect both an obstacle in which the amount of reflected light decreases and an obstacle in which the amount of reflected light increases.

In this case, the displacement due to the thread feed of the optical head is performed with the tracking servo turned off. Therefore, even if there is a portion where tracking cannot be performed on the optical disk due to a disk failure, the tracking cannot be performed. The tracing is not hindered, and tracing can be performed by the optical head over the entire recording area of the disk regardless of the disk failure.

Further, according to the present invention, a failure of the optical disk is determined based on a detection output from the reflected light amount detection circuit, and a failure point determined as the failure is detected using the detection output from the displacement amount detection circuit. Since it is possible to know the position of the disk where the failure point of the optical disk exists, it is easy to find the failure point of the optical disk when performing a visual check,
The failure status of the optical disk can be easily confirmed.

Since the position of the disk where the fault location of the optical disk is present is displayed and expressed,
It is easy to grasp the position of the disk, and in particular, a disk-shaped figure showing the optical disk is displayed on a display controlled by the host computer, and a display showing the location of the failure is displayed on the figure. The disc position can be recognized at a glance.

Also, it is determined from the detection output from the reflected light amount detection circuit and the distribution of the disk position at which the failure location is detected whether the failure of the optical disk is due to a scratch or dirt, and is displayed in different expressions depending on the type of the failure. Is performed, it is easy to understand the reason why the recording cannot be performed, and when the trouble is caused by dirt, the position of the disk from which the dirt is to be removed can be easily recognized.

Further, according to the present invention, the sled feed speed by the optical head and / or the rotational speed for driving the optical disk can be switched by the host computer, so that the measurement interval for measuring the disk failure can be switched. It is possible to make a precise measurement by making the measurement interval dense, to shorten the measurement time by making the measurement interval coarse, or to select measurement conditions for judging a failure of the optical disk according to the situation.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing an embodiment of an optical disk inspection device according to the present invention.

FIG. 2 is an explanatory diagram illustrating a display example of displaying a failure of an optical disk.

[Explanation of symbols]

 Reference Signs List 3 spindle servo circuit 4 optical head 7 servo control circuit 9 reflected light amount detection circuit 12 displacement amount detection circuit 13 data creation circuit 17 command generation means 19 setting means 22 disk failure determination means 23 position detection means 24 display control means 25 display

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G11B 20/18 572 G11B 20/18 572F

Claims (7)

[Claims] An optical disk inspection apparatus for irradiating an optical disk with a light beam emitted from an optical head and detecting an amount of light reflected by the optical disk to detect a failure in the optical disk. An access control circuit for controlling an access operation for displacing in the radial direction of the optical disk; and a reflected light amount detecting circuit for detecting a reflected light amount obtained from the optical head at predetermined time intervals. The optical head is displaced over the entire recording area in the direction, and the detection output from the reflected light amount detection circuit deviates from any of a low level and a high level from a normal level range which is a criterion for judging that the optical disc is in a normal state. The optical disk failure is determined even if the Optical disk inspection device. 2. The method according to claim 1, wherein when the detection output from the reflected light amount detection circuit deviates from the normal level range at a high level, it is determined that the image is a flaw, and a display indicating the flaw is performed. Optical disk device. 3. An optical disk inspection apparatus for irradiating an optical disk with a light beam emitted from an optical head and detecting an amount of light reflected by the optical disk to detect a failure in the optical disk. An access control circuit for controlling an access operation for displacing the trace position in the radial direction of the optical disc; a displacement detection circuit for detecting a displacement position of the optical head; and a reflected light amount for detecting a reflected light amount obtained from the optical head at predetermined time intervals A detection circuit for determining a failure of the optical disc based on a detection output from the reflected light amount detection circuit, and using a detection output from the displacement amount detection circuit to specify a failure portion determined to be the failure. An optical disk inspection device, characterized in that: 4. The optical disk according to claim 1, wherein at the time of disk inspection, the tracking servo of the optical head is turned off and the trace position of the optical head is displaced in the radial direction of the optical disk. apparatus. 5. A host computer generates a command for operating the access control circuit and / or a servo control circuit for controlling a rotation speed for driving an optical disk, and a thread feed speed by an optical head according to the command. 4. The optical disk inspection apparatus according to claim 1, wherein the rotation speed for driving the optical disk is switched. 6. A disk position traced by the optical head based on a displacement position of the optical head detected by using a detection output from the displacement amount detection circuit and a rotation speed at which the optical disk is driven, In addition to detecting the position of the disk where the failure point is determined to be a failure, the failure of the optical disk is determined to be dirt based on the distribution of the disk positions where the failure point is detected, and a display indicating the dirt is displayed. The optical disk inspection apparatus according to claim 3, wherein the inspection is performed. 7. A disk-shaped graphic representing an optical disk is displayed on a display controlled by a host computer, and a display showing a fault location is performed on the graphic. An optical disk inspection device as described in the above.