JP4493534B2 - Dirty detection device for optical pickup, control method thereof, control program, and recording medium - Google Patents

Description

  The present invention relates to a dirt detection device that detects dirt on an optical pickup, a control method therefor, a control program, and a recording medium.

2. Description of the Related Art Conventionally, some disk reproducing apparatuses that reproduce disk type recording media (optical disks) such as CDs (Compact Discs) and DVDs (Digital Versatile Disks) have a function of detecting dirt on the objective lens of an optical pickup. . This type of disc reproducing apparatus determines whether or not the light receiving level of the optical pickup at the time of reproducing the optical disc is equal to or lower than a preset reference level, and determines that the optical pickup is dirty when it is equal to or lower than the reference level. (For example, Patent Document 1).
JP-A-8-315396

However, in the conventional configuration, the same reference level is used for the optical pickup contamination determination in each disk playback device, so the optical pickup contamination detection is performed according to variations in the sensitivity of the optical pickup and other components. Variations in accuracy occur.
Further, in the conventional configuration, if the optical disk is dirty even if the objective lens of the optical pickup is not dirty, the reflectivity of the optical disk is reduced, so that the light reception level of the optical pickup is lowered. There was a problem of false detection when it was dirty. In addition, if it is possible to provide a stain detection device that can determine whether the optical disk is dirty or the optical pickup is dirty, it is possible to accurately notify the user of the stain and provide a more sophisticated stain detection device. can do.

  The present invention has been made in view of the above-described circumstances, and an optical pickup contamination detection apparatus capable of increasing the contamination detection accuracy of the optical pickup without being affected by variations in the sensitivity of the optical pickup, and the like. A control method, a control program, and a recording medium are provided.

In order to solve the above-described problems, the present invention provides a stain detection device for detecting dirt on an optical pickup that irradiates light on an optical disk and receives reflected light, and reproduces information recorded on the optical disk by the optical pickup. And a reproduction history acquisition process for storing information recorded in a predetermined area of the optical disk obtained by the reproduction means as identification information for identifying the optical disk each time the optical disk is inserted. Based on the plurality of identification information stored in step (b), the number of reproduction times of each optical disk is measured, and a light reception level acquisition process for acquiring the light reception level of the optical pickup at the time of reproduction of the optical disk having a predetermined number of reproduction times is performed. from the optical disc receiving level obtained by the light receiving level acquisition process is normal the predetermined range, the light pin A reference disk setting means for setting a reference disk for dirt determination up, based on the received light level of the optical pickup during reproduction of the reference disc, the reference level setting means for setting a reference level for contamination determination of the optical pickup And after the setting of the reference level, when the reference disk is played back, the optical pickup is compared with whether or not the light reception level of the optical pickup is equal to or lower than the reference level. It is characterized by comprising dirt determination means for determining that there is.
According to this configuration, it is possible to set an appropriate reference level that reflects variations in sensitivity and the like of the optical pickup, and it is possible to increase the dirt detection accuracy of the optical pickup.

Te above configuration smell, before Symbol reference disk setting means, creates a light receiving level obtained by the light receiving level acquisition process, the table data stored and the identification information of the optical disc which the light receiving level is acquired in association with, The reference disk is set with reference to this table data, and the dirt determination means compares the information recorded in the predetermined area of the optical disk obtained by the reproduction means with the stored identification information, thereby It may be detected whether the optical disk is set as the reference disk.

Further, in the above configuration, the reference disk setting means sets a plurality of optical disks as reference disks, and is based on an average value of received light levels at the time of reproducing the plurality of reference disks, or at the time of reproducing the reference disk having the largest number of reproductions. The reference level is set based on the received light level of the optical pickup, and the stain determination means causes the optical pickup to become dirty when the received light level of the optical pickup at the time of reproducing a plurality of reference discs is lower than the reference level. It may be determined that In addition, when the dirt determination unit detects a reference disk having a light reception level of the optical pickup equal to or lower than a reference level and the light reception level of another reference disk is higher than the reference level, the light reception level of the optical pickup is It may be determined that an optical disk that has fallen below the reference level is dirty. Moreover, you may provide the alerting | reporting means which alert | reports the determination result of the said dirt determination means.

The present invention also provides a control method for a dirt detection apparatus that has reproducing means for reproducing information recorded on an optical disk by an optical pickup that irradiates the optical disk with light and receives the reflected light, and detects dirt on the optical pickup. In this case, every time the optical disc is inserted, a playback history acquisition process is performed to store information recorded in a predetermined area of the optical disc obtained by the playback means as identification information for specifying the optical disc. Based on a plurality of stored identification information, the number of reproductions of each optical disk is measured, and a light reception level acquisition process is performed for acquiring the light reception level of the optical pickup during reproduction of the optical disk having a predetermined number of reproductions. from the optical disc receiving level obtained by the light receiving level acquisition process is normal the predetermined range, the optical pickup A reference disk setting step of setting a reference disk for dirt determination, based on the received light level of the optical pickup during reproduction of the reference disk, and the reference level setting step of setting a reference level for contamination determination of the optical pickup After setting the reference level, when reproducing the reference disc, it is compared whether or not the light receiving level of the optical pickup is equal to or lower than the reference level. If the light receiving level is equal to or lower than the reference level, the optical pickup is dirty. And a dirt determination step for determining the above.
According to this configuration, it is possible to set an appropriate reference level that reflects variations in sensitivity and the like of the optical pickup, and it is possible to increase the dirt detection accuracy of the optical pickup.

  The present invention is applied to the above-described optical pickup dirt detection apparatus and its control method, and also distributes a control program for carrying out the present invention to general users via an electric communication line. The program may be implemented in such a manner that the program is stored in a computer-readable recording medium such as a magnetic recording medium, an optical recording medium, or a semiconductor recording medium and distributed to general users.

  The present invention measures the number of reproductions of an optical disk, sets an optical disk with a large number of reproductions as a reference disk for determining the dirt of an optical pickup, and determines the level of dirt based on the light receiving level of the optical pickup during reproduction of the reference disk. A reference level is set, and when the optical pickup light reception level during playback of the reference disc falls below the reference level, it is determined that the optical pickup is dirty, so an appropriate reference that reflects variations in the sensitivity of the optical pickup, etc. The level can be set, and the dirt detection accuracy of the optical pickup can be increased.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing a configuration relating to contamination detection of the optical pickup of the disk reproducing apparatus according to the present embodiment.
The disk playback apparatus 10 is an in-vehicle disk playback apparatus that plays back a disk-type recording medium such as a CD (hereinafter referred to as an optical disk 20). The disk playback apparatus 10 includes a display unit 12 including a liquid crystal display device and a user. The instruction input unit 13 for inputting various instructions is reproduced, and the optical disc 20 inserted in the apparatus 10 is reproduced in accordance with the instruction input via the instruction input unit 13, and the sound recorded on the optical disc 20 is reproduced. A sound is generated from a vehicle speaker (not shown).

The optical disc 20 is loaded into the reproducing apparatus 10 by a loading mechanism (not shown) and clamped to the turntable 14. The turntable 14 is rotationally driven by the drive unit 15, whereby the optical disk 20 is rotationally driven.
An optical pickup 30 is disposed in the vicinity of the turntable 14, and the optical pickup 30 receives a laser diode that irradiates a laser beam toward the information recording surface of the optical disc 20 and a light reception that receives reflected light of the laser beam. An element and an optical system such as an objective lens for condensing the irradiation light and the reflected light are provided, and an RF signal indicating a received light level of the reflected light of the laser light, a tracking error signal, and a focus error signal are output. .

  The optical pickup 30 is supported so as to be movable in the radial direction of the optical disc 20, and the radial position of the optical disc 20 is controlled (including tracking control) by the drive unit 15 under the control of the control unit 19. The focus control of the objective lens is performed. The configuration of the optical pickup 30 and the configuration of the disk reproducing apparatus 10 are substantially the same as the conventional one except for the configuration related to contamination detection, and therefore, the portion related to contamination detection will be described in detail below.

The level detection unit 16 detects the signal level of the RF signal output from the optical pickup 30, that is, the light reception level of the optical pickup 30, and the comparison unit 17 determines the light reception level detected by the level detection unit 16. The result is compared with a reference level L0 set by a process described later, and the comparison result is output to the control unit 19. Note that the light reception level of the optical pickup 30 is not limited to being detected by the RF signal, but may be detected by another output signal (focus error signal or tracking error signal) of the optical pickup 30.
The reproducing unit 18 reproduces information stored in the optical disc 20 from the RF signal output from the optical pickup 30 under the control of the control unit 19.

  The control unit 19 controls the entire disc reproducing apparatus 10, and the storage unit 19 </ b> A is a storage area in which data such as various programs including a stain detection control program executed by the control unit 19 is stored in advance ( For example, ROM) and a storage area (for example, RAM or SRAM) in which TOC information read from the optical disc 20 and various flags can be written.

Next, a dirt detection process for detecting dirt on the optical pickup 30 of the disk reproducing apparatus 10 will be described. FIG. 2 is a flowchart showing the dirt detection process.
First, the control unit 19 controls the drive unit 15 to identify TOC (Table Of Contents) information (identification) every time the optical disc 20 is inserted in order to identify the optical disc 20 with a large number of reproductions. Information) is read, and reproduction history acquisition processing for sequentially storing the information in the storage unit 19A is started (step S1).
Then, the control unit 19 starts the reproduction history acquisition process, and when a certain period of time elapses or when TOC information of a predetermined number of optical disks is accumulated, the control unit 19 counts the number for each TOC information, The number of reproductions of the optical disk corresponding to each TOC information is counted, and a light reception level acquisition process for acquiring the light reception level of the optical pickup 30 at the time of reproduction of the optical disk when the number of reproductions is a predetermined number or more (for example, two or more) is started (step S2).

  Specifically, every time the optical disc 20 is inserted, the control unit 19 reads the TOC information of the optical disc 20, and determines whether or not the TOC information matches the TOC information of the optical disc that has been played a predetermined number of times or more. When the optical disc 30 is judged and matched, the level detection unit 16 detects the light reception level of the optical pickup 30 during reproduction of the optical disc (including reading of the TOC information), and associates the detected light reception level with the TOC information. The data is stored in the storage unit 19A. As a result, as shown in FIG. 3, the storage unit 19A stores the TOC information (TOC1, TOC2,...) Of the optical disc 20 that has been reproduced a predetermined number of times or more, and the received light levels (LEVEL 1, LEVEL 2) during reproduction of each optical disc. ,... Are associated with each other.

Next, the control unit 19 refers to the table data T1 to identify the optical disc 20 whose light reception level is equal to or higher than the lower limit level L1 of the normal range set in advance, that is, the optical disc 20 whose light reception level is within the normal range. Among the identified optical discs 20, the top two optical discs with the highest number of reproductions are set as reference discs for determining dirt on the optical pickup (step S3). Note that the number of reference disks may be three or more.
Subsequently, the control unit 19 refers to the table data T1, and sets a value obtained by subtracting a predetermined offset amount from the light reception level at the time of reproducing the standard disc as the reference level L0 for the dirt determination of the optical pickup 30 (step S1). S4). In this case, the reference level L0 may be a value obtained by subtracting the offset amount from the average value of the received light levels at the time of reproduction of a plurality of reference discs, or the offset amount from the received light level at the time of reproduction of the reference disc having the largest number of reproductions. It is good also as a value which subtracted.

When the reference level L0 is set, the control unit 19 determines from the TOC information of the inserted optical disk 20 whether or not the optical disk 20 set as the reference disk has been inserted. The level detection unit 16 detects the light reception level of the optical pickup 30 during disk reproduction (including reading of TOC information), and the comparison unit 17 obtains a comparison result between the light reception level and the reference level L0 (step S5). ).
When the light reception level at the time of reproducing the reference disk is higher than the reference level L0 (step S6: NO), the control unit 19 performs this step until it is detected that the light reception level at the time of reproducing the reference disk is equal to or lower than the reference level L0. The process of S4 is repeatedly executed. If the optical disk 20 set as the reference disk is not inserted within the predetermined period in the process of step S4, the control unit 19 removes the optical disk 20 from the registration of the reference disk, and the optical disk 20 having the next highest number of reproductions. A reference disk change process for setting the reference disk to the reference disk is executed.

  On the other hand, when the light reception level at the time of reproducing the reference disk is equal to or lower than the reference level (step S6: YES), the control unit 19 records a decrease in the light reception level in the storage unit 19A (step S7). A process of acquiring the light reception level of the optical pickup 30 is started (step S8). In the process of step S8, when the control unit 19 detects the insertion of another reference disk, the level detection unit 16 acquires the light reception level of the optical pickup 30 when the reference disk is reproduced, and the light reception level and the reference level L0. Get the comparison result with.

  Here, when the light reception level during reproduction of another reference disk is equal to or lower than the reference level L0 (step S9: YES), the optical pickup is initially applied to a plurality of reference disks whose light reception level of the optical pickup 30 is greater than the reference level L0. Since the light reception level 30 is equal to or lower than the reference level L0, it can be determined that the optical pickup 30 is dirty. Therefore, in such a case, the control unit 19 performs a first notification process for notifying the dirt of the optical pickup 30 (step S10). Specifically, the first notification process is a process of displaying a warning such as “lens is dirty” on the display unit 12 or a process of reporting a sound to that effect from the speaker. This can prompt the user to clean the optical pickup 30.

On the other hand, if the received light level at the time of playback of another reference disc is higher than the reference level L0 (step S9: NO), the optical disc 20 is more likely to be dirty than the optical pickup 30 is likely to be dirty. 19 executes a second notification process for notifying the contamination of the optical disc 20 (step S11).
This second notification process is a process for notifying that when a dirty optical disk 20 is inserted. Specifically, the control unit 19 detects an optical disk whose reference light level is equal to or lower than the reference level L0 (reference value). 20) (including the disc), predetermined information is written in the table data T1 or the like, and each time the optical disc 20 is inserted, it is determined whether or not the optical disc 20 has a light reception level equal to or lower than the reference level L0. If it is the optical disk 20, a notification process for notifying that the optical disk 20 is dirty (for example, a process of displaying a warning “optical disk is dirty” on the display unit 12) is performed. This can prompt the user to clean the optical disc 20.

  After executing the first notification process, the control unit 19 clears the table data T1 and proceeds to the process of step S1, and after executing the second notification process, after the predetermined period has elapsed, The table data T1 is cleared, and the process proceeds to step S1. As a result, the above-described contamination detection process of the optical pickup 30 is repeatedly executed, and the contamination of the optical pickup 30 or the contamination of the optical disk 20 is continuously monitored.

As described above, in this configuration, among the optical discs 20 inserted into the disc playback apparatus 10, the optical disc 20 that has been played a large number of times and the light receiving level of the optical pickup 30 during the playback of the optical disc is within the normal range. Is set as the reference disk, and the reference level L0 for dirt determination is set from the light receiving level of the optical pickup 30 at the time of reproduction of the reference disk, so that an appropriate reference level L0 reflecting variations in sensitivity of the optical pickup 30 is set. Can be set.
In addition, in this configuration, the optical pickup 30 is determined to be dirty when the light reception level at the time of reproducing a plurality of reference discs is equal to or less than the reference level L0. Thus, the dirt detection accuracy of the optical pickup 30 can be improved.

In addition, since the optical disk 20 that is frequently reproduced by the user is set as the reference disk, when the optical pickup 30 is contaminated, the contamination of the optical pickup 30 can be notified in a relatively short time.
Furthermore, in this configuration, when the reference disk whose light reception level of the optical pickup 30 is lower than the reference level L0 and the reference disk whose light reception level of the optical pickup 30 is higher than the reference level L0 are mixed, the light reception level of the optical pickup 30 is Since it is determined that the optical disk 20 having the reference level L0 or lower is dirty, the dirty optical disk 20 can also be detected. For this reason, it is possible to provide a highly functional dirt detecting device as compared with the conventional apparatus that notifies that the optical pickup is dirty even when the optical disk is dirty.

Embodiments described above, only only one aspect of the present invention, optionally to a variant can der within the scope of the present invention. In the embodiment above mentioned, it has dealt with the case of applying the present invention to automotive type disc reproducing apparatus, may be applied to a disk reproducing apparatus other than vehicle, also the disc structure for contamination detection of an optical pickup It is not limited to the case of being built in the playback device, but a dedicated dirt detection device can also be configured.

  In the above-described embodiment, the case where the control program for detecting the contamination of the optical pickup is previously stored in the storage unit 19A has been described. However, this control program is stored in the magnetic recording medium, the optical recording medium, and the semiconductor recording. The program may be stored in a computer-readable recording medium such as a medium, and the computer may read and execute the control program from the recording medium. Further, the control program may be downloaded from a distribution server or the like via a communication network (electric communication line).

It is a block diagram which shows the structure in connection with the contamination detection of the optical pick-up of the disc reproducing | regenerating apparatus concerning this embodiment. It is a flowchart which shows a stain | pollution | contamination detection process. It is a figure which shows an example of table data.

Explanation of symbols

10 Disc player 12 Display unit (notification means)
13 instruction input unit 15 drive unit 16 level detection unit 17 comparison unit 18 reproduction unit (reproduction means)
19 Control unit (reference disk setting means, reference level setting means, dirt determination means)
19A Storage unit 20 Optical disc 30 Optical pickup

Claims (8)

In a dirt detection device that detects dirt on an optical pickup that irradiates an optical disk with light and receives the reflected light,
Reproducing means for reproducing information recorded on the optical disc by the optical pickup;
Each time the optical disk is inserted, information recorded in a predetermined area of the optical disk obtained by the reproducing means is stored as identification information for identifying the optical disk, and is stored in the reproduction history acquisition process. Based on the plurality of identification information, the number of reproductions of each optical disk is measured, and a light reception level acquisition process is performed to acquire the light reception level of the optical pickup during reproduction of the optical disk with a predetermined number of reproductions. A reference disk setting means for setting a reference disk for dirt determination of the optical pickup from among the optical disks in which the light reception level acquired in the acquisition process is within a predetermined normal range ;
A reference level setting means for setting a reference level for dirt determination of the optical pickup based on a light receiving level of the optical pickup at the time of reproducing the reference disk;
After setting the reference level, when reproducing the reference disc, it is compared whether or not the light receiving level of the optical pickup is equal to or lower than the reference level. If the light receiving level is equal to or lower than the reference level, the optical pickup is dirty. A dirt detecting device for optical pickup, comprising: a dirt judging means for judging. The reference disk setting means creates table data in which the received light level acquired in the received light level acquisition process is stored in association with the identification information of the optical disk from which the received light level is acquired, and the table data is referred to To set the reference disc,
  The dirt determination means detects whether or not the optical disk is set to the reference disk by comparing the information recorded in a predetermined area of the optical disk obtained by the reproducing means with the stored identification information. The dirt detection device for an optical pickup according to claim 1. The reference disc setting means sets a plurality of optical discs as reference discs, and is based on an average value of received light levels at the time of reproducing a plurality of reference discs or based on a received light level at the time of reproducing a reference disc having the largest number of reproductions. Set the reference level,
  3. The dirt determination means determines that the optical pickup is dirty when a light receiving level of the pickup during reproduction of a plurality of reference discs is equal to or lower than a reference level. The optical pickup dirt detection device as described. The contamination determination means is configured such that, after a light receiving level of the optical pickup is detected that is lower than a reference level, and a light receiving level at another reference disk is greater than the reference level, the light receiving level of the optical pickup is the reference level. 4. The optical pickup contamination detecting apparatus according to claim 3, wherein the optical disc determined as follows is determined to be dirty. 5. The dirt detecting device for an optical pickup according to claim 1, further comprising a notifying means for notifying a judgment result of the dirt judging means. In a control method of a dirt detection device that has a reproducing means for reproducing information recorded on an optical disk by an optical pickup that irradiates the optical disk with light and receives the reflected light, and detects dirt on the optical pickup.
Each time the optical disk is inserted, information recorded in a predetermined area of the optical disk obtained by the reproducing means is stored as identification information for identifying the optical disk, and is stored in the reproduction history acquisition process. Based on the plurality of identification information, the number of reproductions of each optical disk is measured, and a light reception level acquisition process is performed to acquire the light reception level of the optical pickup during reproduction of the optical disk with a predetermined number of reproductions. A reference disk setting step for setting a reference disk for dirt determination of the optical pickup from among optical disks in which the light reception level acquired in the acquisition process is within a predetermined normal range;
  A reference level setting step for setting a reference level for dirt determination of the optical pickup based on the light receiving level of the optical pickup at the time of reproducing the reference disk;
  After setting the reference level, when reproducing the reference disc, it is compared whether or not the light receiving level of the optical pickup is equal to or lower than the reference level. If the light receiving level is equal to or lower than the reference level, the optical pickup is dirty. A dirt judgment step to judge;
  A control method for a dirt detection device for an optical pickup, characterized in that: In a control program for controlling by a computer a dirt detection device that detects dirt on an optical pickup that irradiates light on an optical disk and receives its reflected light,
  Reproducing means for reproducing information recorded on the optical disc by the optical pickup;
Each time the optical disk is inserted, information recorded in a predetermined area of the optical disk obtained by the reproducing means is stored as identification information for identifying the optical disk, and is stored in the reproduction history acquisition process. Based on the plurality of identification information, the number of reproductions of each optical disk is measured, and a light reception level acquisition process is performed to acquire the light reception level of the optical pickup during reproduction of the optical disk with a predetermined number of reproductions. A reference disk setting means for setting a reference disk for dirt determination of the optical pickup from among the optical disks in which the light reception level acquired in the acquisition process is within a predetermined normal range;
  A reference level setting means for setting a reference level for dirt determination of the optical pickup based on a light receiving level of the optical pickup at the time of reproducing the reference disk;
  After setting the reference level, when reproducing the reference disc, it is compared whether or not the light receiving level of the optical pickup is equal to or lower than the reference level. If the light receiving level is equal to or lower than the reference level, the optical pickup is dirty. A control program for functioning as a dirt determination means. A computer-readable recording medium having the control program according to claim 7 recorded thereon.

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