JP2006107574A - Device and method to drive optical disk, recording medium and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more accurately obtain the size of stray light components included in a received light signal. <P>SOLUTION: An offset function computing section 241 computes an offset function based on the value of a stray light received signal stored in a memory and the value of an output light received light signal and supplies the coefficients of the offset function to the memory. A stray light component computing section 242 obtains the coefficients of the offset function from the memory and computes a stray light predicting value based on the obtained coefficients of the offset function and the value of the output light received light signal supplied from a DSP. This invention is applicable to an optical disk driving device or the like which records data on an optical disk. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical disc driving apparatus and method, a recording medium, and a program, and more particularly, to an optical disc driving apparatus and method, a recording medium, and a program capable of more accurately setting a laser power.

  In recent years, optical disk type recording media such as CD-R (Compact Disk Recordable), CD-RW (Compact Disk Rewritable), and magneto-optical disk have become widespread. When data is recorded on this optical disk, the optimum power level of the laser irradiated on the optical disk differs depending on the optical disk system (standard) or material.

  Therefore, when recording data on this optical disk, the optical disk drive device changes the power of the laser applied to the optical disk in a stepwise manner, and stores the data in an area called a PCA (Power Calibration Area) area on the optical disk. Test recording is performed by recording. Then, the optical disk drive reproduces the data recorded in the PCA area, and sets the optimum power of the laser when data is recorded on the optical disk based on the value of the RF signal that is the reproduction signal.

  The conventional optical disk drive calculates the average value of the RF signal value, and sets the optimum power of the laser at the time of recording based on the calculated average value of the RF signal (see, for example, Patent Document 1). .

JP 2003-99931 A

  However, in particular, in an optical disc driving apparatus using an integrated optical pickup, the light emitting portion of the optical pickup emits light, and the light receiving portion of the optical pickup reflects the light (laser) reflected from the optical disc among the emitted light. Not only is it reflected on the optical disc, but also so-called stray light, which is light that is directly incident on the light receiving portion of the optical pickup, is received, so that there is a problem that an accurate RF signal value cannot be measured. .

  That is, as shown in FIG. 1, when the optical disk 11 is mounted on the optical disk drive, the light source 22 integrated on the integrated substrate 21 emits a laser (light). Here, the arrows in the figure indicate the optical paths of the light emitted from the light source 22.

  The light emitted from the light source 22 is reflected by the reflecting surface 41 of the prism 23, collimated by the collimator lens 24, and enters the objective lens 25. The light incident on the objective lens 25 is irradiated onto the optical disc 11, reflected by the optical disc 11, and incident on the objective lens 25 again.

  The light incident on the objective lens 25 is collimated and enters the collimator lens 24. The light incident on the collimator lens 24 is collected and enters the prism 23 from the reflection surface 41 of the prism 23. The light incident on the prism 23 is received by the light receiving unit 26 integrated on the integrated substrate 21 or reflected at the end face thereof.

  The light reflected on the end surface of the light receiving unit 26 is reflected again on the end surface of the prism 23 and received by the light receiving unit 27 integrated on the integrated substrate 21. The light received by the light receiving unit 26 and the light receiving unit 27 is converted into an electric signal in the optical disc driving device, and as a result, an RF signal is obtained.

  On the other hand, as indicated by the dotted arrows in the figure, some of the light emitted from the light source 22 is directly reflected on the prism 23 without being reflected by the reflecting surface 41 of the prism 23. The light directly incident on the prism 23 is called stray light, and is reflected at the end face of the integrated substrate 21 or received by the light receiving unit 27. The light received by the light receiving unit 27 is converted into an electric signal in the optical disk driving device.

  As described above, the optical disk drive device receives not only the light reflected on the optical disk but also the stray light. As a method for solving this problem, the magnitude of a signal obtained by converting the received stray light into an electric signal (hereinafter referred to as a stray light receiving signal) is measured in advance, and the light received by the light receiving unit is converted into an electric signal. By subtracting the magnitude of the stray light received signal from the magnitude of the signal (hereinafter referred to as the received light signal) obtained by doing this, the magnitude (value) of the component of the received light signal with respect to the reflected light can be obtained. Proposed.

  Here, FIG. 2 is a diagram showing the magnitudes of the light reception signal and the stray light reception signal with respect to the intensity of the laser (light) that emits light.

  In the figure, the vertical axis indicates the magnitude of the signal (voltage), and the horizontal axis indicates the power (intensity) of the laser that emits light. A straight line R1 indicates the magnitude of the received light signal with respect to the laser power, and a straight line M1 indicates the magnitude of the stray light received signal with respect to the laser power.

  The magnitude of the light reception signal increases in proportion to the power of the laser that emits light. When the power of the laser is P1, the magnitude of the light reception signal is V2. The magnitude of the stray light reception signal increases in proportion to the power of the laser that emits light. When the power of the laser is P1, the magnitude of the stray light reception signal is V1.

  When the optical disk driving device measures the magnitude of the stray light reception signal at the laser power P1, the optical disk driving device emits a laser (light) having a power of P1 without mounting the optical disk 11 on the optical disk driving device. To do. At this time, since the optical disk 11 is not mounted in the optical disk drive device, the light reflected by the reflecting surface 41 of the prism 23 diverges and does not enter the prism 23.

  On the other hand, light (stray light) that is directly reflected on the prism 23 without being reflected by the reflecting surface 41 of the prism 23 is received by the light receiving unit 27. In this way, the optical disk drive receives only stray light and obtains the magnitude V1 of the stray light reception signal in advance. Then, the optical disk drive device measures the magnitude V2 of the received light signal with the optical disk 11 mounted, and subtracts the magnitude V1 of the stray light received signal from the measured magnitude V2 of the received light signal. The magnitude | size (V2-V1) of the component with respect to the reflected light can be calculated | required.

  However, in the above-described method, when the intensity of emitted light is changed, it is very difficult to accurately measure the magnitude of the component of the received light signal with respect to the reflected light (hereinafter referred to as the reflected light component). It is difficult to.

  Here, FIG. 3 is a diagram showing the magnitude of the received light signal when the intensity of the emitted light is changed.

  In the figure, the vertical axis indicates the magnitude of the signal (voltage), and the horizontal axis indicates time. R21 and R22 indicate the magnitude of the received light signal, and M21 indicates the magnitude of the component for the stray light (hereinafter referred to as the stray light component) of the received light signal obtained by converting the stray light into an electrical signal. Show.

  R21 indicates the magnitude of the received light signal that does not include the stray light received signal when the intensity of the emitted light is changed, that is, the ideal received light signal.

  The magnitude R21 of the received light signal changes between P21 and P22. That is, the magnitude R21 of the received light signal changes from P21 to P22 at time t1, and changes from P22 to P23 at time t2. At time t3, the magnitude R21 of the received light signal returns from P23 to P21, and thereafter periodically changes between P21, P22, and P23.

  M21 indicates the magnitude of the stray light component when the intensity of the emitted light is changed. The magnitude M21 of the stray light component changes between P31 and P32. That is, the magnitude M21 of the stray light component changes from P31 to P32 at time t11, and changes from P32 to P33 at time t12. At time t13, the magnitude M21 of the stray light component returns from P33 to P31, and thereafter periodically changes between P31, P32, and P33.

  R22 indicates the magnitude of the received light signal including the component in which the stray light is converted when the intensity of the emitted light is changed, that is, the magnitude of the received light signal including the reflected light component and the stray light component. Show. Therefore, the magnitude (value) R22 of the received light signal is a value obtained by adding the magnitude M21 of the stray light component to the magnitude of the reflected light component.

  The magnitude R22 of the received light signal changes between P32 and P34. That is, the magnitude R22 of the received light signal changes from P32 to P34 at time t11, and changes from P34 to P35 at time t12. At time t13, the magnitude R22 of the received light signal returns from P35 to P32, and thereafter periodically changes between P32, P34, and P35.

  That is, when the optical disk drive receives stray light, the maximum value of the received light signal R22 is larger than the maximum value of the ideal received light signal R21 by (P34-P22), and this difference is It is equal to the maximum value P32 of the magnitude M21 of the stray light component. Similarly, when the optical disc driving apparatus receives stray light, the minimum value of the magnitude R22 of the received light signal is larger than the minimum value of the ideal magnitude R21 of the received light signal by (P32−P21), and this difference is , Equal to the minimum value P31 of the magnitude M21 of the stray light component.

  As described above, when the light intensity is changed, the magnitude of the stray light component changes with the change in the intensity of the emitted light. Therefore, the magnitude of the stray light component corresponding to the intensity of the emitted light is accurately obtained. I can't. There is a problem that the magnitude of the received light signal to be measured is observed as if the magnitude of the RF signal is modulated.

  Therefore, it is very difficult to accurately measure only the magnitude (value) of the stray light component corresponding to the intensity of the emitted light, and as a result, the power of the emitted laser when data is recorded on the optical disc. There was a problem that the setting of could not be performed accurately.

  Also, when reproducing data recorded on the optical disk, the power of the light emitted from the optical disk drive device changes due to a temperature change or the like, and therefore the magnitude (value) of the stray light component corresponding to the intensity of the emitted light. It is very difficult to accurately measure only the laser beam emitted from the optical disk. As a result, there is a problem that the power of the laser that emits light cannot be set accurately when reproducing data recorded on the optical disk. It was.

  The present invention has been made in view of such a situation, and makes it possible to more accurately measure the magnitude of a stray light component corresponding to the intensity of emitted light.

  The optical disk drive apparatus according to the present invention reads the first value indicating the intensity of the light emitted to the optical disk and the data recorded on the optical disk, or records the data on the optical disk. Indicates the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light irradiated on the optical disk received by the light receiving means that receives the reflected light that has been irradiated and reflected by the optical disk. Function calculating means for calculating a function representing a correspondence relationship with the second value based on the plurality of first values and the plurality of second values, and reading data recorded on the optical disc, or When recording data, when the intensity of emitted light is changed with time, a third value and function indicating the intensity of light received by the light receiving means are used to receive the data. Characterized in that it comprises a reflection light intensity calculation means for calculating a fourth value indicating the intensity of reflected light received by the means.

  The optical disk drive device further includes stray light intensity calculation means for calculating stray light intensity for each of a plurality of intensities, which is the intensity of light irradiated to the optical disk using a function. The fourth value can be calculated based on the value of 3 and the calculated intensity of stray light.

  The optical disc driving apparatus includes difference calculating means for calculating a difference between the fourth value obtained in advance and the fourth value calculated by the reflected light intensity calculating means, and light emitted by the calculated difference. Correction means for correcting the intensity of the emitted light can be further provided so that the intensity of the light increases or decreases.

  In the optical disk driving method of the present invention, when the light is emitted and the first value indicating the intensity of the light applied to the optical disk and the data recorded on the optical disk are read or the data is recorded on the optical disk, Indicates the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light irradiated on the optical disk received by the light receiving means that receives the reflected light that has been irradiated and reflected by the optical disk. A function calculating step for calculating a function representing a correspondence relationship with the second value based on the plurality of first values and the plurality of second values, and reading data recorded on the optical disc, or When recording data, when the intensity of emitted light is changed with time, the third value and function indicating the intensity of light received by the light receiving means are used. Characterized in that it comprises a fourth reflected light intensity calculation step of calculating the value of which indicates the intensity of the reflected light received by the light receiving means.

  The program of the recording medium of the present invention is a case where the first value indicating the intensity of light emitted to the optical disc and the data recorded on the optical disc are read or the data is recorded on the optical disc. The intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light emitted by the light receiving means that receives the reflected light that has been irradiated and reflected by the optical disk. A function calculating step for calculating a function representing a correspondence relationship with the second value shown based on the plurality of first values and the plurality of second values, and reading data recorded on the optical disc, or reading the optical disc In the case of recording data, when the intensity of emitted light is changed with time, the third value and function indicating the intensity of light received by the light receiving means are used. , Characterized in that it comprises a fourth value reflected light intensity calculation step of calculating a representing the intensity of reflected light received by the light receiving means.

  The program of the present invention is a light emitting light, and reads out a first value indicating the intensity of light irradiating the optical disc and data recorded on the optical disc, or records data on the optical disc in the optical disc. Second light indicating the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light irradiated on the optical disk received by the light receiving means that receives the reflected reflected light. A function calculation step for calculating a function representing a correspondence relationship between the first value and the second value, and reading data recorded on the optical disc, or In the case of recording, when the intensity of the emitted light is changed with time, the third value and function indicating the intensity of the light received by the light receiving means are used. Characterized in that to execute a fourth value reflected light intensity calculation step of calculating a representing the intensity of the reflected light received to the computer by.

  In the optical disk drive device and method, the recording medium, and the program of the present invention, the first value indicating the intensity of the light to be emitted and applied to the optical disk and the data recorded on the optical disk are read, Or, when recording data on an optical disc, the reflected light is reflected by the optical disc out of the emitted light corresponding to the intensity of the light applied to the optical disc received by the light receiving means that receives the reflected light that is irradiated and reflected by the optical disc. A function representing the correspondence relationship with the second value indicating the intensity of only stray light that has not been calculated is calculated based on the plurality of first values and the plurality of second values, and the data recorded on the optical disc is read out When recording data on an optical disk, the intensity of light received by the light receiving means is shown when the intensity of emitted light is changed with time. Using a third value and functions, a fourth value indicating the intensity of the reflected light received by the light receiving means is calculated.

  The optical disc driving apparatus of the present invention reads out the first value indicating the intensity of light specified by the light intensity setting value that specifies the intensity of light to be emitted and the data recorded on the optical disc or the data on the optical disc. In the case of recording the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light irradiated to the optical disk received by the light receiving means that receives the reflected reflected light that is irradiated to the optical disk. A function calculating means for calculating a function representing a correspondence relationship with the second value indicating only the intensity based on the plurality of first values and the plurality of second values, and reading data recorded on the optical disc Or when recording data on an optical disc, when the intensity of the emitted light is changed with time, a third value indicating the intensity of the light received by the light receiving means and With few, characterized in that it comprises a reflection light intensity calculation means for calculating a fourth value indicating the intensity of the reflected light received by the light receiving means.

  In the optical disk drive device of the present invention, the first value indicating the light intensity specified by the light intensity setting value specifying the intensity of the emitted light and the data recorded on the optical disk are read or the optical disk is read. When recording data, the light emitted from the optical disc corresponding to the intensity of the light applied to the optical disc received by the light receiving means that receives the reflected reflected light that has been applied to the optical disc is not reflected by the optical disc. A function representing a correspondence relationship with a second value indicating the intensity of only stray light is calculated based on the plurality of first values and the plurality of second values, and reads data recorded on the optical disc, or When data is recorded on an optical disk, a third value and a function indicating the intensity of light received by the light receiving means are changed when the intensity of emitted light is changed with time. There are, fourth value indicating the intensity of the reflected light received by the light receiving means is calculated.

  The optical disk drive apparatus according to the present invention reads the first value indicating the intensity of the light emitted to the optical disk and the data recorded on the optical disk, or records the data on the optical disk. Indicates the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light irradiated on the optical disk received by the light receiving means that receives the reflected light that has been irradiated and reflected by the optical disk. A function representing a correspondence relationship with the second value, and using the function supplied from the external device, calculates the intensity of the light irradiating the optical disc, and the stray light intensity for each of the plurality of intensities. When reading the data recorded on the optical disk or recording the data on the optical disk, the intensity of the emitted light is changed with time. The reflection for calculating the fourth value indicating the intensity of the reflected light received by the light receiving means based on the third value indicating the intensity of the light received by the light receiving means and the calculated intensity of the stray light. And a light intensity calculating means.

  In the optical disk drive device of the present invention, when the first value indicating the intensity of light emitted to the optical disk and the data recorded on the optical disk are read or the data is recorded on the optical disk The intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light emitted by the light receiving means that receives the reflected light that has been irradiated and reflected by the optical disk. A function representing a correspondence relationship with the second value shown, and using the function supplied from the external device, the intensity of light irradiating the optical disk, and the intensity of stray light for each of a plurality of intensities is calculated When reading data recorded on an optical disc or recording data on an optical disc, the intensity of emitted light is changed with time. It can, based on the intensity of the third value and the calculated stray indicating the intensity of light received at the light receiving means, a fourth value indicating the intensity of the reflected light received by the light receiving means is calculated.

  The network is a mechanism in which at least two devices are connected and information can be transmitted from one device to another device. The devices that communicate via the network may be independent devices, or may be internal blocks that constitute one device.

  The communication is not only wireless communication and wired communication, but also communication in which wireless communication and wired communication are mixed, that is, wireless communication is performed in a certain section and wired communication is performed in another section. May be. Further, communication from one device to another device may be performed by wired communication, and communication from another device to one device may be performed by wireless communication.

  The optical disk drive device may be an independent device, or may be a block that performs a recording process or a reproducing process of the recording / reproducing apparatus.

  According to the present invention, the power of a laser that emits light can be set. Further, according to the present invention, the magnitude of the stray light component corresponding to the intensity of the emitted light can be measured more accurately.

  Embodiments of the present invention will be described below. The correspondence relationship between the invention described in this specification and the embodiments of the invention is exemplified as follows. This description is intended to confirm that the embodiments supporting the invention described in this specification are described in this specification. Therefore, although there is an embodiment which is described in the embodiment of the invention but is not described here as corresponding to the invention, it means that the embodiment is not It does not mean that it does not correspond to the invention. Conversely, even if an embodiment is described herein as corresponding to an invention, that means that the embodiment does not correspond to an invention other than the invention. Absent.

  Further, this description does not mean all the inventions described in this specification. In other words, this description is for the invention described in the present specification, which is not claimed in this application, that is, for the invention that will be applied for in the future or that will appear and be added by amendment. It does not deny existence.

  The optical disc drive apparatus according to claim 1 reads out a first value indicating the intensity of light emitted to the optical disc and data recorded on the optical disc, or records data on the optical disc. In this case, the intensity of the light irradiated on the optical disc received by the light receiving means (for example, the light receiving unit 137-1 and the light receiving unit 137-2 in FIG. 5) that receives the reflected light that is irradiated onto the optical disc and reflected is received. Based on the plurality of first values and the plurality of second values, a function representing a correspondence relationship with the second value indicating the intensity of only the stray light that is not reflected by the optical disk among the corresponding emitted light is used. The function calculation means for calculating (for example, the offset function calculation unit 241 in FIG. 11) and the data recorded on the optical disk are read or the data is emitted when the data is recorded on the optical disk. When the light intensity is changed with time, a fourth value indicating the intensity of the reflected light received by the light receiving means is calculated using a third value and function indicating the intensity of the light received by the light receiving means. Reflected light intensity calculating means (for example, a reflected light component calculating unit 243 in FIG. 11) is provided.

  The optical disk drive apparatus according to claim 2 is a stray light intensity calculating unit (for example, FIG. 11) that calculates the intensity of the stray light for each of the plurality of intensities using the function. A stray light component calculation unit 242), and the reflected light intensity calculation means (for example, the reflected light component calculation unit 243 in FIG. 11) calculates the fourth value based on the third value and the calculated stray light intensity. It is characterized by calculating.

  The optical disk drive apparatus according to claim 3 is a difference between the fourth value obtained in advance and the fourth value calculated by the reflected light intensity calculating means (for example, the reflected light component calculating unit 243 in FIG. 11). The difference calculation means (for example, the difference calculation unit 244 in FIG. 11) for calculating the light intensity is corrected so that the intensity of the emitted light increases or decreases by the magnitude of the calculated difference. And correction means (for example, the APC amplifier 84 in FIG. 4).

  According to a fourth aspect of the present invention, there is provided an optical disc driving method, wherein the first value indicating the intensity of the light emitted to the optical disc and the data recorded on the optical disc are read or the data is recorded on the optical disc. In this case, the intensity of the light irradiated on the optical disc received by the light receiving means (for example, the light receiving unit 137-1 and the light receiving unit 137-2 in FIG. 5) that receives the reflected light that is irradiated onto the optical disc and reflected is received. Based on the plurality of first values and the plurality of second values, a function representing a correspondence relationship with the second value indicating the intensity of only the stray light that is not reflected by the optical disk among the corresponding emitted light is used. When a function calculation step to calculate (for example, the process of step S39 in FIG. 14) and data recorded on the optical disk are read or data is recorded on the optical disk, light is emitted. When the intensity of the light is changed with time, the third value and the function indicating the intensity of the light received by the light receiving means are used to calculate the fourth value indicating the intensity of the reflected light received by the light receiving means. And a light intensity calculation step (for example, step S98 in FIG. 17).

  Note that the recording medium according to claim 5 and the program according to claim 6 are basically the same processing as the optical disc driving method according to claim 4 described above, and are therefore repeated, so that the description thereof is omitted. To do.

  The optical disk drive apparatus according to claim 7 reads out a first value indicating the intensity of light specified by a light intensity setting value specifying the intensity of emitted light and data recorded on the optical disk, or When data is recorded on the optical disc, the optical disc irradiated with the light receiving means (for example, the light receiving portion 137-1 and the light receiving portion 137-2 in FIG. 5) that receives the reflected reflected light that is irradiated onto the optical disc is irradiated onto the optical disc. A function representing a correspondence relationship with the second value indicating the intensity of only the stray light that is not reflected by the optical disc among the emitted light, corresponding to the intensity of the received light, is expressed by a plurality of first values and a plurality of second values. The function calculation means (for example, the offset function calculation unit 241 in FIG. 11) that calculates based on the value of the value and the data recorded on the optical disk are read or the data is recorded on the optical disk In the case where the intensity of the emitted light is changed with time, the fourth value indicating the intensity of the reflected light received by the light receiving means using the third value and function indicating the intensity of the light received by the light receiving means. And a reflected light intensity calculating means (for example, a reflected light component calculating unit 243 in FIG. 11).

  The optical disk drive device according to claim 8 reads the first value indicating the intensity of the light emitted to the optical disk and the data recorded on the optical disk, or records the data on the optical disk. In this case, the intensity of the light irradiated on the optical disc received by the light receiving means (for example, the light receiving unit 137-1 and the light receiving unit 137-2 in FIG. 5) that receives the reflected light that is irradiated onto the optical disc and reflected is received. Corresponding function representing a correspondence relationship with the second value indicating the intensity of only the stray light that is not reflected by the optical disc among the emitted light, and is supplied from an external device (for example, PC 352 in FIG. 26). The stray light intensity calculating means for calculating the stray light intensity for each of the plurality of intensities using the function (for example, the stray light component in FIG. 29). When reading out data recorded on the output unit 491) and the optical disk or recording data on the optical disk, when the intensity of the emitted light is changed with time, the first light intensity indicating the intensity of the light received by the light receiving means is shown. Based on the value of 3 and the calculated stray light intensity, the reflected light intensity calculating means for calculating the fourth value indicating the intensity of the reflected light received by the light receiving means (for example, the reflected light component calculating section 492 in FIG. 29). ).

  The present invention can be applied to an optical disk drive device for recording data on an optical disk.

  First, a first embodiment to which the present invention is applied will be described.

  FIG. 4 is a block diagram showing an example of the configuration of an optical disk drive device to which the present invention is applied.

  The optical disc driving device 61 reproduces data recorded on the optical disc 62 mounted on the optical disc driving device 61. Further, the optical disk drive device 61 records desired data on the optical disk 62 mounted on the optical disk drive device 61. Here, the optical disk 62 may be a recording medium that reads or records data by light, such as a CD-R, CD-RW, or magneto-optical disk.

  The optical disk drive 61 includes a microcomputer 81, a spindle motor drive circuit 82, a spindle motor 83, an APC (Automatic Power Control) amplifier 84, an LDD (Laser Diode Driver) 85, an optical pickup 86, an optical signal amplifier 87, and a servo matrix amplifier 88. , A DSP (Digital Signal Processor) 89, a drive amplifier 90, an actuator 91, a memory 92, and a drive 93.

  The microcomputer 81 (hereinafter also referred to as the microcomputer 81) generates a signal for turning on or off the focus servo, and supplies the DSP 89 with a signal for turning on or off the generated focus servo. The microcomputer 81 supplies data to be recorded on the optical disc 62 to the DSP 89.

  The microcomputer 81 generates a power signal that specifies the power of the laser that emits light, and supplies the generated power signal to the APC amplifier 84. The microcomputer 81 generates a signal indicating that the optical disk 62 is rotationally driven, and supplies the generated signal indicating that the optical disk 62 is rotationally driven to the spindle motor driving circuit 82.

  The microcomputer 81 calculates an offset function, which is a function indicating a predicted stray light value with respect to the value of the output light intensity signal, based on the value of the stray light reception signal and the value of the output light intensity signal stored in the memory 92. The microcomputer 81 supplies the calculated offset function coefficient to the memory 92.

  Here, the stray light reception signal is a signal generated based on light (hereinafter, referred to as stray light) received by the optical pickup 86 without being irradiated on the optical disc 62 among the light emitted from the optical pickup 86. Say. The output light intensity signal is generated based on the received light by receiving a part of light emitted from the optical pickup 86 (hereinafter referred to as output light). A signal indicating the intensity of light. Details of the stray light reception signal and the output light intensity signal will be described later.

  The predicted stray light value is the magnitude of the stray light component included in the received light signal that is generated based on the light (reflected light) that is reflected on the optical disc 62 and received by the optical pickup 86 out of the received light. Is obtained by substituting the value of the output light intensity signal into the offset function.

  The microcomputer 81 uses the coefficient of the offset function stored in the memory 92 and the magnitude of the reflected light component included in the received light signal based on the value of the received light signal and the value of the output light intensity signal supplied from the DSP 89. The predicted value (hereinafter referred to as reflected light predicted value) is calculated. The microcomputer 81 supplies the calculated reflected light predicted value and a value indicating the power of the laser designated by the power signal (hereinafter referred to as a power setting value) to the memory 92.

  That is, since the received light signal includes the reflected light component and the stray light component, the microcomputer 81 uses the offset function coefficient stored in the memory 92 and the value of the output light intensity signal supplied from the DSP 89. Based on the output light intensity signal value, a stray light prediction value is calculated. Then, the microcomputer 81 subtracts the calculated stray light prediction value from the value of the light reception signal supplied from the DSP 89, thereby predicting the magnitude of the reflected light component included in the light reception signal. Calculate the predicted value.

  The microcomputer 81 selects an optimum laser power setting value when data is recorded on the optical disc 62 based on the value of the received light signal supplied from the DSP 89. The microcomputer 81 temporarily stores the selected power setting value. Hereinafter, when data is recorded on the optical disc 62, the power of the laser emitted from the optical disc driving device 61 is also referred to as recording power.

  The microcomputer 81 calculates a predicted reflected light value based on the value of the output light intensity signal supplied from the DSP 89 and the coefficient of the offset function stored in the memory 92. The microcomputer 81 calculates a difference between the calculated reflected light predicted value and the reflected light predicted value stored in the memory 92 and temporarily stored in the power setting value, and the laser specified by the power signal is calculated. The power signal is generated so that the power increases or decreases by the calculated difference.

  The microcomputer 81 reads the program supplied from the drive 93 that is mounted as necessary, and executes the read program. In addition, when a program or data is supplied from the drive 93, the microcomputer 81 supplies the supplied program or data to the memory 92 as necessary, reads the program stored in the memory 92, and reads the read program. Execute.

  The spindle motor driving circuit 82 rotates the spindle motor 83 based on a signal supplied from the microcomputer 81 to rotate the optical disk 62. The spindle motor 83 rotationally drives the optical disc 62 mounted on the spindle based on the control of the spindle motor drive circuit 82.

  The APC amplifier 84 generates an output control signal that determines the intensity of light emitted by the optical pickup 86 based on the output light intensity signal supplied from the optical signal amplifier 87 and the power signal supplied from the microcomputer 81. The generated output control signal is supplied to the LDD 85. That is, the APC amplifier 84 changes the light emitted from the optical pickup 86 that changes due to temperature change, stray light, etc., based on the output light intensity signal supplied from the optical signal amplifier 87 and the power signal supplied from the microcomputer 81. An output control signal is generated so as to correct the intensity, and the generated output control signal is supplied to the LDD 85.

  The LDD 85 generates a drive signal for light emission based on the output control signal supplied from the APC amplifier 84 during reproduction, and supplies the generated drive signal to the optical pickup 86. Further, the LDD 85 generates a drive signal based on the output control signal supplied from the APC amplifier 84 and the modulated data supplied from the DSP 89 during recording, and supplies the generated drive signal to the optical pickup 86. To do.

  The optical pickup 86 emits a laser (light) based on the drive signal supplied from the LDD 85. The optical pickup 86 receives the return light and converts the received light into an electrical signal indicating the intensity of the received light. The optical pickup 86 supplies an electric signal indicating the intensity of the converted light to the optical signal amplifier 87. Here, the return light refers to stray light or light reflected on the optical disc 62 (reflected light) among the light emitted from the optical pickup 86. That is, a light reception signal is generated based on an electrical signal indicating the intensity of the received return light.

  The optical pickup 86 receives the output light, and converts the received output light into an output light intensity signal that is an electric signal indicating the intensity of the received light. The optical pickup 86 supplies the converted output light intensity signal to the optical signal amplifier 87.

  Further, the optical pickup 86 is driven under the actuator 91 and is subjected to focus control and tracking control.

  The optical signal amplifier 87 amplifies the electric signal indicating the intensity of the received light supplied from the optical pickup 86 and supplies the electric signal indicating the intensity of the amplified light to the servo matrix amplifier 88. The optical signal amplifier 87 amplifies the output light intensity signal supplied from the optical pickup 86 and supplies the amplified output light intensity signal to the DSP 89 and the APC amplifier 84. The optical signal amplifier 87 may be included in the optical pickup 86.

  The servo matrix amplifier 88 extracts (generates) an RF signal (stray light reception signal or light reception signal), tracking error signal, or focus error signal from the electrical signal supplied from the optical signal amplifier 87, and extracts the extracted RF signal (stray light). A light receiving signal or a light receiving signal), a tracking error signal, or a servo error signal is supplied to the DSP 89.

  Here, the tracking error signal is a signal indicating a tracking error, and the magnitude of the signal varies depending on the amount of tracking error (amount indicating deviation from the track). The focus error signal is a signal indicating a focus error, and the magnitude of the signal varies depending on the amount of focus error.

  The DSP 89 performs a phase compensation process on the tracking error signal supplied from the servo matrix amplifier 88 to generate a tracking control signal for controlling tracking, and supplies the generated tracking control signal to the drive amplifier 90. To do. The DSP 89 generates and generates a focus control signal for controlling the focus based on the focus error signal supplied from the servo matrix amplifier 88 and the signal for turning on or off the focus servo supplied from the microcomputer 81. A focus control signal is supplied to the drive amplifier 90.

  The DSP 89 performs predetermined processing such as gain correction processing and A / D conversion (analog / digital conversion) processing on the stray light reception signal supplied from the servo matrix amplifier 88, and stores the value of the stray light reception signal that has been processed. 92. The DSP 89 performs predetermined processing such as gain correction processing and A / D conversion processing on the output light intensity signal supplied from the optical signal amplifier 87, and supplies the value of the processed output light intensity signal to the memory 92. .

  The DSP 89 performs predetermined processing such as decoding, gain correction processing, and A / D conversion processing on the light reception signal supplied from the servo matrix amplifier 88 and supplies the processed light reception signal value to the microcomputer 81. The DSP 89 performs predetermined processing such as gain correction processing and A / D conversion processing on the output light intensity signal supplied from the optical signal amplifier 87, and supplies the processed value of the output light intensity signal to the microcomputer 81. .

  The DSP 89 modulates the data supplied from the microcomputer 81 by a predetermined method, and supplies the modulated data to the LDD 85.

  The drive amplifier 90 drives the actuator 91 based on the tracking control signal or the focus control signal supplied from the DSP 89.

  The actuator 91 drives the optical pickup 86 under the control of the drive amplifier 90 to move the optical pickup 86 relative to the optical disc 62.

  The memory 92 is composed of, for example, a non-volatile memory such as a semiconductor memory, and stores the value of the stray light receiving signal and the value of the output light intensity signal supplied from the DSP 89. The memory 92 stores a coefficient of an offset function, a reflected light prediction value, a power setting value, a program, or data supplied from the microcomputer 81. The memory 92 supplies the microcomputer 81 with the stored stray light received signal value, output light intensity signal value, offset function coefficient, reflected light predicted value, power setting value, program, or data.

  When the magnetic disk 111, the optical disk 112, the magneto-optical disk 113, the semiconductor memory 114, or the like is mounted, the drive 93 drives them to acquire programs and data recorded therein. The acquired program and data are transferred to the microcomputer 81.

  Note that a program recorded on the optical disc 62 may be read out and the read program may be executed by the microcomputer 81.

  Next, a more detailed configuration of the optical pickup 86 will be described with reference to FIGS. 6 to 10, the same reference numerals are given to the portions corresponding to the case in FIG. 5, and the description thereof will be omitted because it is repeated.

  In FIG. 5, the arrow indicates the optical path of light. The optical pickup 86 is configured to include an integrated substrate 131, a light source 132, a light receiving unit 133, a prism 134, a collimator lens 135, an objective lens 136, a light receiving unit 137-1, and a light receiving unit 137-2.

  On the end surface 151 of the integrated substrate 131, the light source 132, the light receiving unit 133, the prism 134, the light receiving unit 137-1, and the light receiving unit 137-2 are integrated.

  The light source 132 is composed of, for example, an LD (Laser Diode) or the like, and emits a laser (light) having a predetermined intensity (intensity) in accordance with a drive signal supplied from the LDD 85.

  The light receiving unit 133 is composed of, for example, a PD (Photo Diode) or the like, receives a part of light emitted from the light source 132 (output light), and is an output light intensity signal that is an electric signal corresponding to the intensity of the received light. Convert to The light receiving unit 133 supplies the converted output light intensity signal to the optical signal amplifier 87.

  The prism 134 reflects or transmits the light emitted from the light source 132. The reflecting surface 152 of the prism 134 reflects the light emitted from the light source 132 and causes the reflected light to enter the collimator lens 135.

  The collimator lens 135 collimates the light reflected by the reflecting surface 152 of the prism 134 and incident on the collimator lens 135, and generates parallel light rays. The collimator lens 135 causes the generated parallel rays to enter the objective lens 136.

  The objective lens 136 condenses the light incident from the collimator lens 135 and irradiates the optical disc 62. The objective lens 136 collimates the light reflected on the optical disk 62 and incident on the objective lens 136, and generates parallel rays. The objective lens 136 causes the generated parallel rays to enter the collimator lens 135.

  The collimator lens 135 collects the light incident from the objective lens 136 and causes the collected light to enter the reflecting surface 152 of the prism 134. The reflecting surface 152 of the prism 134 transmits the light incident from the collimator lens 135 and causes the light to enter the light receiving unit 137-1.

  The light receiving unit 137-1 includes, for example, a PD or the like, and receives or reflects light (return light) transmitted through the reflecting surface 152 of the prism 134. The light receiving unit 137-1 converts the received light into an electric signal corresponding to the intensity of the light, and supplies the converted electric signal to the optical signal amplifier 87.

  The prism 134 reflects the light reflected by the light receiving unit 137-1 on the end surface opposite to the end surface on the light receiving unit 137-1 side, and enters the light receiving unit 137-2. The light receiving unit 137-2 is made of, for example, PD, and receives light reflected from the end face of the prism 134. The light receiving unit 137-2 converts the received light into an electric signal corresponding to the intensity of the light, and supplies the converted electric signal to the optical signal amplifier 87.

  Here, the light reflected by the optical disc 62 and received by the light receiving unit 137-1 or the light receiving unit 137-2 is converted into an electric signal by the light receiving unit 137-1 or the light receiving unit 137-2. The electric signal converted in the light receiving unit 137-1 or the light receiving unit 137-2 is extracted as an RF signal (light receiving signal) in the servo matrix amplifier 88. Hereinafter, when it is not necessary to distinguish between the light receiving unit 137-1 and the light receiving unit 137-2, they are simply referred to as the light receiving unit 137.

  6 is a view of the optical pickup 86 shown in FIG. 5 as viewed from above in FIG.

  Each of the light source 132, the light receiving unit 133, the light receiving unit 137-1, and the light receiving unit 137-2 is arranged (integrated) on the end surface 151 of the integrated substrate 131 so as to be arranged in a straight line. In addition, the prism 134 is arranged such that light emitted from the light source is incident on the reflecting surface 152 of the prism 134 at a predetermined angle.

  FIG. 7 is a diagram illustrating an end surface on the light receiving side of the light receiving unit 137-1. In the figure, regions Q1 to Q4 represent regions on the light receiving side end surface of the light receiving unit 137-1, and an ellipse D1 represents a cross section of light received by the light receiving unit 137-1, and regions W1 to W4. Represents a region surrounded by the ellipse D1 and each of the regions Q1 to Q4.

  The end surface on the light receiving side of the light receiving unit 137-1 is divided into four regions Q1 to Q4. The light receiving unit 137-1 converts the light received in each of the regions Q1 to Q4 into an electric signal corresponding to the intensity of the light, and supplies the converted electric signal to the optical signal amplifier 87.

  That is, the light receiving unit 137-1 receives light incident on the region W1 surrounded by the ellipse D1 and the region Q1 in the region Q1 of the light receiving unit 137-1, and the received light according to the light intensity. The electric signal is converted into an electric signal, and the converted electric signal is supplied to the optical signal amplifier 87.

  In addition, in the region Q2 of the light receiving unit 137-1, the light receiving unit 137-1 receives light incident on the region W2 surrounded by the ellipse D1 and the region Q2, and the received light according to the light intensity. The electric signal is converted into an electric signal, and the converted electric signal is supplied to the optical signal amplifier 87. In the region Q3 of the light receiving unit 137-1, the light receiving unit 137-1 receives light incident on the region W3 surrounded by the ellipse D1 and the region Q3, and the received light is an electric signal corresponding to the intensity of the light. And the converted electrical signal is supplied to the optical signal amplifier 87. Similarly, in the region Q4 of the light receiving unit 137-1, the light receiving unit 137-1 receives light incident on the region W4 surrounded by the ellipse D1 and the region Q4, and receives the received light according to the light intensity. The converted electric signal is supplied to the optical signal amplifier 87.

  The tracking error signal and the focus error signal are generated based on an electrical signal corresponding to the intensity of light received in each of the areas Q1 to Q4. For example, when the area W4 is smaller than the area W1, the servo matrix amplifier 88 generates a tracking error signal indicating that the light emitted from the light source 132 is shifted upward from the center in the figure. To do.

  FIG. 8 is a diagram illustrating an end surface on the light receiving side of the light receiving unit 137-2. In the figure, regions Q21 to Q24 represent regions on the light receiving side end surface of the light receiving unit 137-2, and an ellipse D21 represents a cross section of light received by the light receiving unit 137-2, and regions W21 to W24. Represents a region surrounded by the ellipse D21 and each of the regions Q21 to Q24.

  The light receiving side end surface of the light receiving unit 137-2 is divided into four regions Q21 to Q24. The light receiving unit 137-2 converts the light received in each of the regions Q21 to Q24 into an electric signal corresponding to the intensity of the light, and supplies the converted electric signal to the optical signal amplifier 87.

  That is, the light receiving unit 137-2 receives light incident on the region W21 surrounded by the ellipse D21 and the region Q21 in the region Q21 of the light receiving unit 137-2, and receives the received light according to the intensity of the light. The electric signal is converted into an electric signal, and the converted electric signal is supplied to the optical signal amplifier 87.

  In addition, in the region Q22 of the light receiving unit 137-2, the light receiving unit 137-2 receives light incident on the region W22 surrounded by the ellipse D21 and the region Q22, and the received light according to the light intensity. The electric signal is converted into an electric signal, and the converted electric signal is supplied to the optical signal amplifier 87. In the region Q23 of the light receiving unit 137-2, the light receiving unit 137-2 receives light incident on the region W23 surrounded by the ellipse D21 and the region Q23, and the received light is an electric signal corresponding to the intensity of the light. And the converted electrical signal is supplied to the optical signal amplifier 87. Similarly, in the region Q24 of the light receiving unit 137-2, the light receiving unit 137-2 receives light incident on the region W24 surrounded by the ellipse D21 and the region Q24, and receives the received light according to the light intensity. The converted electric signal is supplied to the optical signal amplifier 87.

  The tracking error signal and the focus error signal are generated based on an electrical signal corresponding to the intensity of light received in each of the areas Q21 to Q24. For example, when the area of the region W24 is smaller than the area of the region W21, the servo matrix amplifier 88 generates a tracking error signal indicating that the light emitted from the light source 132 is shifted upward from the center in the drawing. To do.

  The light reception signal extracted (generated) by the servo matrix amplifier 88 may be generated based on an electrical signal corresponding to the intensity of the return light received in the regions Q1 to Q4 (FIG. 7). You may make it produce | generate based on the electrical signal according to the intensity | strength of the return light received in the area | region Q21 thru | or area | region Q24. Further, the light reception signal generated by the servo matrix amplifier 88 may be generated based on an electrical signal corresponding to the intensity of the return light received in the regions Q1 to Q4 and the regions Q21 to Q24.

  FIG. 9 is a diagram for explaining stray light received by the optical pickup 86. In the figure, arrows indicate the optical paths of light.

  The light emitted from the light source 132 is reflected by the reflecting surface 152 of the prism 134 or transmitted through the reflecting surface 152 of the prism 134. Part of the light (stray light) transmitted through the reflecting surface 152 of the prism 134 enters the light receiving unit 137-2 and is received by the light receiving unit 137-2. The light receiving unit 137-2 converts the received light into an electric signal corresponding to the intensity of the light, and supplies the converted electric signal to the optical signal amplifier 87. Then, the electric signal converted in the light receiving unit 137-2 is extracted in the servo matrix amplifier 88 as a stray light received signal or a stray light component of the received light signal.

  10 is a view of the optical pickup 86 shown in FIG. 9 as viewed from above in FIG. In FIG. 10, an arrow indicates an optical path of light, and an ellipse D41 indicates a cross section of light incident on the end surface of the prism 134 on the light receiving unit 137 side.

  Of the light emitted from the light source 132, the light (stray light) transmitted through the reflecting surface 152 of the prism 134 is incident on the end surface of the prism 134 on the light receiving unit 137 side. The end surface of the light incident on the end surface of the prism 134 on the light receiving unit 137 side has an elliptical shape as indicated by an ellipse D41. The light receiving unit 137-2 transmits the reflection surface 152 of the prism 134 and receives light incident on the light receiving unit 137-2. The light receiving unit 137-2 converts the received light into an electric signal corresponding to the intensity of the light, and supplies the converted electric signal to the optical signal amplifier 87.

  FIG. 11 is a block diagram illustrating a functional configuration of the microcomputer 81.

  The microcomputer 81 is configured to include a control unit 221 and a calculation unit 222.

  The control unit 221 generates a signal for turning on or off the focus servo, and supplies the DSP 89 with a signal for turning on or off the generated focus servo. The control unit 221 supplies data to be recorded on the optical disc 62 to the DSP 89.

  The control unit 221 generates a power signal that specifies the power of the laser that emits light, and supplies the generated power signal to the APC amplifier 84. The control unit 221 generates a signal indicating that the optical disk 62 is rotationally driven, and supplies the generated signal indicating that the optical disk 62 is rotationally driven to the spindle motor driving circuit 82.

  The calculation unit 222 calculates a difference between the offset function, the stray light predicted value, the reflected light predicted value, and the reflected light predicted value. The calculation unit 222 is configured to include an offset function calculation unit 241, a stray light component calculation unit 242, a reflected light component calculation unit 243, and a difference calculation unit 244.

  The offset function calculation unit 241 of the calculation unit 222 calculates an offset function based on the stray light reception signal value and the output light intensity signal value stored in the memory 92, and the calculated offset function coefficient is stored in the memory 92. Supply.

  The stray light component calculation unit 242 of the calculation unit 222 calculates a predicted stray light value for the value of the output light intensity signal based on the offset function coefficient stored in the memory 92 and the value of the output light intensity signal supplied from the DSP 89. calculate.

  The reflected light component calculation unit 243 of the calculation unit 222 calculates and calculates a reflected light predicted value based on the stray light predicted value calculated by the stray light component calculation unit 242 of the calculation unit 222 and the value of the received light signal supplied from the DSP 89. The reflected light prediction value and the power setting value are supplied to the memory 92.

  The difference calculation unit 244 of the calculation unit 222 is the optimum laser power (recording power) when recording data on the optical disc 62 based on the reflected light predicted value calculated by the reflected light component calculation unit 243 of the calculation unit 222. Select. That is, the difference calculation unit 244 of the calculation unit 222 selects an optimum power setting value when data is recorded on the optical disc 62 based on the predicted reflected light value calculated by the reflected light component calculation unit 243 of the calculation unit 222. To do. The difference calculation unit 244 of the calculation unit 222 temporarily stores the selected power setting value.

  The difference calculation unit 244 of the calculation unit 222 reflects the reflected light in the predicted reflected light value calculated by the reflected light component calculation unit 243 of the calculation unit 222 and the power setting value stored temporarily in the memory 92. A difference from the predicted value is calculated, and the calculated difference is supplied to the control unit 221.

  The control unit 221 generates a power signal so that the laser power specified by the power signal increases or decreases by the difference supplied from the calculation unit 222.

  The control unit 221 reads a program supplied from the drive 93 that is mounted as necessary, and executes the read program. In addition, when a program or data is supplied from the drive 93, the control unit 221 supplies the supplied program or data to the memory 92 as necessary, reads the program stored in the memory 92, and reads the read program. Execute.

  FIG. 12 is a block diagram illustrating a functional configuration of the memory 92.

  The memory 92 includes storage areas 281 to 283.

  The storage area 281 of the memory 92 is a predetermined storage area in the memory 92 and stores the value of the stray light reception signal and the value of the output light intensity signal supplied from the DSP 89. The storage area 281 of the memory 92 supplies the stored stray light reception signal value and output light intensity signal value to the microcomputer 81.

  The storage area 282 of the memory 92 is a predetermined storage area in the memory 92 and stores the coefficient of the offset function supplied from the microcomputer 81. The storage area 282 of the memory 92 supplies the stored offset function coefficient to the microcomputer 81.

  The storage area 283 of the memory 92 is a predetermined storage area in the memory 92 and stores the reflected light prediction value and the power setting value supplied from the microcomputer 81. The storage area 283 of the memory 92 supplies the stored reflected light prediction value and power setting value to the microcomputer 81.

  The memory 92 stores various data, programs, and the like. The memory 92 supplies various data and programs stored therein to the microcomputer 81.

  Next, the stray light measurement process by the optical disc drive 61 will be described with reference to the flowchart of FIG.

  In step S <b> 11, the control unit 221 generates a signal for turning off the focus servo, and supplies the DSP 89 with a signal for turning off the generated focus servo.

  In step S <b> 12, the DSP 89 generates a focus control signal for controlling the focus based on the signal for turning off the focus servo supplied from the microcomputer 81, and supplies the generated focus control signal to the drive amplifier 90. To do.

  In step S13, the drive amplifier 90 turns off the focus servo based on the focus control signal supplied from the DSP 89. The actuator 91 drives the optical pickup 86 under the control of the drive amplifier 90 and moves the optical pickup 86 so that, for example, light emitted from the light source 132 does not form an image on the optical disc 62.

  In step S14, the optical disc driving device 61 performs an offset function calculation process. Although details of the offset function calculation process will be described later, in the offset function calculation process, the optical disc driving device 61 calculates and calculates an offset function based on the value of the stray light reception signal and the value of the output light intensity signal. The coefficient of the offset function is supplied to the memory 92.

  In step S15, the storage area 282 of the memory 92 stores the coefficient of the offset function supplied from the microcomputer 81, and the stray light measurement process ends.

  In this way, the optical disc driving device 61 calculates the offset function and stores the calculated coefficient of the offset function.

  Thus, by calculating the offset function, the magnitude of the stray light component corresponding to the intensity of the emitted light can be obtained more accurately. The optical disk driving device 61 may perform the stray light measurement process with the optical disk 62 mounted on the optical disk driving device 61, or the stray light measurement with the optical disk 62 not mounted on the optical disk driving device 61. You may make it perform the process of. Further, when the stray light measurement process is performed in a state where the optical disk 62 is not loaded in the optical disk drive device 61, the focus servo may be turned on.

  The offset function calculation process corresponding to the process of step S14 of FIG. 13 will be described with reference to the flowchart of FIG.

  In step S <b> 31, the control unit 221 generates a power signal indicating that light is emitted with a predetermined power, and supplies the generated power signal to the APC amplifier 84. The APC amplifier 84 generates an output control signal based on the power signal supplied from the microcomputer 81 and the output light intensity signal supplied from the optical signal amplifier 87, and supplies the generated output control signal to the LDD 85.

  More specifically, in step S31, the control unit 221 acquires the measurement start power setting value, the measurement end power setting value, and the step width, which are determined in advance when performing test writing, from the memory 92, and acquires the acquired measurement. Based on the start power setting value, the measurement end power setting value, and the step width, a power signal for emitting light at a predetermined power is generated, and the generated power signal is supplied to the APC amplifier 84. The control unit 211 supplies predetermined data to the DSP 89, and the DSP 89 modulates the data supplied from the control unit 221 by, for example, an EFM (Eight to Fourteen Modulation) method, and supplies the modulated data to the LDD 85. To do.

  Here, the measurement start power set value is the smallest power of the lasers that emit light when the optical disk drive 61 changes the power of the laser applied to the optical disk 62 stepwise. It is a power setting value for setting to. The optical disc driving device 61 increases the laser power by a step width step by step, and the stray light intensity is measured until the stray light intensity (value of the stray light reception signal) is measured with the power set to the measurement end power setting value. Continue measuring.

  In step S32, the LDD 85 generates a drive signal for emitting light based on the output control signal supplied from the APC amplifier 84 and the data supplied from the DSP 89, and sends the generated drive signal to the optical pickup 86. Supply.

  In step S <b> 33, the light source 132 emits a laser for recording data on the optical disk 62 based on the drive signal supplied from the LDD 85.

  In step S <b> 34, the light receiving unit 137 receives stray light, converts the received stray light into an electric signal corresponding to the intensity of the received light, and supplies the converted electric signal to the optical signal amplifier 87. Then, the optical signal amplifier 87 amplifies the electrical signal supplied from the light receiving unit 137 and supplies the amplified electrical signal to the servo matrix amplifier 88. In this case, since the focus servo is turned off, the light emitted from the light source 132 diverges without being imaged on the optical disk 62. Therefore, since the light (reflected light) reflected by the optical disc 62 does not enter the light receiving unit 137, the component of the return light received by the light receiving unit 137 is only stray light.

  In step S <b> 35, the servo matrix amplifier 88 generates a stray light reception signal based on the electrical signal supplied from the optical signal amplifier 87 and supplies the generated stray light reception signal to the DSP 89. For example, in step S35, the servo matrix amplifier 88 extracts an electrical signal corresponding to the intensity of stray light received in the regions Q1 to Q4 (FIG. 7) from the electrical signals supplied from the optical signal amplifier 87. Thus, a stray light reception signal is generated, and the generated stray light reception signal is supplied to the DSP 89.

  In step S36, the light receiving unit 133 receives the output light, converts the received output light into an output light intensity signal, which is an electrical signal corresponding to the intensity of the output light, and converts the converted output light intensity signal into light. The signal is supplied to the signal amplifier 87. The optical signal amplifier 87 amplifies the output light intensity signal supplied from the light receiving unit 137 and supplies the amplified output light intensity signal to the DSP 89 and the APC amplifier 84.

  In step S37, the DSP 89 performs predetermined processing on the stray light reception signal supplied from the servo matrix amplifier 88 and the output light intensity signal supplied from the optical signal amplifier 87, and the values of the stray light reception signal and the output light intensity signal are calculated. The value is supplied to the memory 92. The storage area 281 of the memory 92 stores the value of the stray light reception signal and the value of the output light intensity signal supplied from the DSP 89.

  For example, in step S37, the DSP 89 performs processing such as A / D conversion and gain correction processing on the stray light reception signal supplied from the servo matrix amplifier 88 and the output light intensity signal supplied from the optical signal amplifier 87, and stray light. The value of the light reception signal and the value of the output light intensity signal are supplied to the memory 92. The storage area 281 of the memory 92 stores the value of the stray light reception signal and the value of the output light intensity signal supplied from the DSP 89.

  In step S38, the control unit 221 determines whether or not the value of the stray light reception signal has been measured with all predetermined power setting values.

  For example, as shown in FIG. 15, the optical disk drive 61 measures the value of the stray light reception signal by changing the power in four stages. In the figure, the vertical axis represents the power of the laser emitted from the optical disk drive 61, and the horizontal axis represents time.

  That is, the optical disk drive 61 emits light so that the power of the emitted laser becomes P51, and measures the value of the stray light reception signal. In this case, the power setting value at which the power of the laser emitted by the optical disc driving device 61 is P51 is the measurement start power setting value. Then, the optical disc driving device 61 emits light by increasing the power of the emitted laser by the step width d. That is, the optical disc driving device 61 emits light so that the power of the emitted laser becomes (P51 + d), and measures the value of the stray light reception signal.

  Next, the optical disk drive 61 emits light by further increasing the power of the emitted laser by the step width d. That is, the optical disk drive 61 emits light so that the power of the emitted laser is (P51 + 2d), and measures the value of the stray light reception signal. Then, the optical disk drive 61 emits light by further increasing the power of the emitted laser by the step width d. That is, the optical disk drive 61 emits light so that the power of the emitted laser becomes (P51 + 3d), and measures the value of the stray light reception signal. Here, the power setting value at which the power of the laser emitted by the optical disc driving device 61 is (P51 + 3d) is the measurement end power setting value.

  Therefore, for example, when the optical disk drive 61 emits light so that the power of the emitted laser becomes (P51 + 3d) and measures the value of the stray light reception signal in step S38, the control unit 221 determines the value of the stray light reception signal. Is determined to be measured at all predetermined power setting values.

  If it is determined in step S38 that measurement has not been performed for all predetermined power setting values, the value of the stray light reception signal has not been measured for all power setting values, and the procedure proceeds to step S31. Return.

  On the other hand, when it is determined in step S38 that the measurement is performed with all the predetermined power setting values, the values of the stray light reception signal are measured for all the power setting values, so the control unit 221 calculates the offset function. And a signal for calculating the generated offset function is supplied to the calculation unit 222. In step S39, when a signal indicating that the offset function is calculated is supplied from the control unit 221, the offset function calculation unit 241 of the calculation unit 222 outputs the value and output of the stray light reception signal stored in the memory 92. An offset function is calculated based on the value of the light intensity signal. The offset function calculation unit 241 of the calculation unit 222 supplies the calculated offset function coefficient to the memory 92, and the process ends.

  For example, the offset function calculation unit 241 of the calculation unit 222 calculates the coefficient of the polynomial shown in Equation (1) by the least square method based on the value of the stray light reception signal and the value of the output light intensity signal stored in the memory 92. By calculating, an offset function is calculated.

Y = A0 + A1 (X) + A2 (X ² ) +... + (An) (X ⁿ ) (1)

  Here, Y is the value of the stray light reception signal, and X is the value of the output light intensity signal. In other words, the offset function calculation unit 241 of the calculation unit 222 uses the coefficient of the polynomial shown in Equation (1) by the least square method based on the value of the stray light reception signal and the value of the output light intensity signal stored in the memory 92. An offset function is calculated by calculating A0, A2, A3,..., An).

  The offset function can be approximated as a linear expression. However, since the light divergence angle of the laser changes depending on the power of the laser emitted from the optical disc driving device 61, the value of the stray light received signal is the output light intensity. Since it is not necessarily proportional to the value of the signal, it is desirable to use a polynomial.

  In this way, the optical disk drive 61 calculates an offset function.

  Thus, by calculating the offset function, the magnitude of the stray light component corresponding to the intensity of the emitted light can be obtained more accurately. When the offset function is an nth order equation, it is desirable to change the power setting value stepwise and measure the value of the stray light reception signal and the value of the output light intensity signal of (n + 1) or more.

  The value of the received light signal varies depending on the type of the optical disk 62 to be mounted on the optical disk driving device 61, when data is recorded on the optical disk 62, when data is read from the optical disk 62, etc. Gain correction processing (gain mode) is performed so that the value is equal to or greater than a predetermined value. In this case, since the optical disk drive device 61 has a different gain value for each type of operation of the optical disk 62 and operations such as writing to and reading from the optical disk 62, the optical disk drive device 61 is used to minimize electrical offset and gain deviation. Stores an offset function coefficient equal to or greater than the number of stored gain values.

  With reference to the flowchart of FIG. 16, the trial writing process by the optical disk drive 61 will be described.

  In step S <b> 61, the stray light component calculation unit 242 of the calculation unit 222 acquires a coefficient of the offset function stored in the memory 92. When the stray light component calculation unit 242 of the calculation unit 222 acquires the coefficient of the offset function, the stray light component calculation unit 242 generates a signal indicating that the coefficient of the offset function has been acquired, and generates a signal indicating that the coefficient of the offset function has been acquired. To supply.

  In step S62, when a signal indicating that the coefficient of the offset function has been acquired is supplied from the calculation unit 222, the control unit 221 generates a signal indicating that the focus servo is turned on, and turns on the generated focus servo. The signal is supplied to the DSP 89.

  In step S63, the DSP 89 generates a focus control signal for controlling the focus based on the signal for turning on the focus servo supplied from the microcomputer 81, and supplies the generated focus control signal to the drive amplifier 90. To do.

  In step S64, the drive amplifier 90 turns on the focus servo based on the focus control signal supplied from the DSP 89. The actuator 91 drives the optical pickup 86 under the control of the drive amplifier 90 and moves the optical pickup 86 so that, for example, the light emitted from the light source 132 forms an image on the optical disc 62.

  In step S65, the optical disc driving device 61 performs a reflected light predicted value calculation process. Although details of the reflected light predicted value calculation process will be described later, in the reflected light predicted value calculation process, the optical disc driving device 61 changes predetermined power by changing the issued power (recording power) stepwise. Is recorded on the optical disk 62. Then, the value of the received light signal and the value of the output light intensity signal are measured at a predetermined timing, and the reflected light predicted value is calculated.

  In step S66, the optical disc driving device 61 performs a power setting value selection process, and the trial writing process ends. Although details of the power setting value selection process will be described later, in the power setting value selection process, the optical disc driving device 61 reproduces data recorded on the optical disc 62 and calculates an accurate reflected light prediction value. Thus, the optimum power setting value is selected when data is recorded on the optical disc 62.

  In this way, the optical disc driving device 61 calculates the reflected light prediction value using the coefficient of the offset function, and selects an optimum power setting value when data is recorded on the optical disc 62.

  Thus, by calculating the reflected light predicted value using the offset function coefficient, it is possible to select an optimum power setting value when data is recorded on the optical disc 62.

  Next, the reflected light predicted value calculation process corresponding to the process of step S65 of FIG. 16 will be described with reference to the flowchart of FIG.

  In step S <b> 91, the control unit 221 generates a power signal indicating that light is emitted with a predetermined power, and supplies the generated power signal to the APC amplifier 84. The APC amplifier 84 generates an output control signal based on the power signal supplied from the microcomputer 81 and the output light intensity signal supplied from the optical signal amplifier 87, and supplies the generated output control signal to the LDD 85.

  More specifically, in step S91, the control unit 221 acquires the measurement start power setting value, the measurement end power setting value, and the step width, which are determined in advance when performing test writing, from the memory 92, and acquires the acquired measurement. Based on the start power setting value, the measurement end power setting value, and the step width, a power signal for emitting light at a predetermined power is generated, and the generated power signal is supplied to the APC amplifier 84. In addition, the control unit 221 supplies a power setting value for setting the power specified by the power signal to the calculation unit 222. The control unit 211 supplies predetermined data to the DSP 89, and the DSP 89 modulates the data supplied from the control unit 221 by, for example, the EFM method, and supplies the modulated data to the LDD 85.

  In step S92, the LDD 85 generates a drive signal for emitting light based on the output control signal supplied from the APC amplifier 84 and the data supplied from the DSP 89, and sends the generated drive signal to the optical pickup 86. Supply.

  In step S <b> 93, the light source 132 emits a laser based on the drive signal supplied from the LDD 85 and records data on the optical disk 62.

  In step S <b> 94, the light receiving unit 137 receives the return light, converts the received return light into an electrical signal corresponding to the intensity of the light, and supplies the converted electrical signal to the optical signal amplifier 87. Then, the optical signal amplifier 87 amplifies the electrical signal supplied from the light receiving unit 137 and supplies the amplified electrical signal to the servo matrix amplifier 88. In this case, since the focus servo is turned on, the light emitted from the light source 132 is reflected by the optical disc 62, passes through the reflecting surface 152 of the prism 134, and enters the light receiving unit 137. Therefore, the return light received by the light receiving unit 137 includes light reflected by the optical disk 62 (reflected light) and stray light as return light components.

  In step S 95, the servo matrix amplifier 88 generates a light reception signal based on the electrical signal supplied from the optical signal amplifier 87, and supplies the generated light reception signal to the DSP 89. For example, in step S95, the servo matrix amplifier 88 extracts an electrical signal corresponding to the intensity of the return light received in the regions Q1 to Q4 (FIG. 7) from the electrical signals supplied from the optical signal amplifier 87. As a result, a light reception signal is generated, and the generated light reception signal is supplied to the DSP 89.

  Further, the DSP 89 performs predetermined processing such as A / D conversion, gain correction processing, and decoding on the light reception signal supplied from the servo matrix amplifier 88, and the value of the light reception signal subjected to the predetermined processing is reduced to the microcomputer. 81.

  In step S96, the light receiving unit 133 receives the output light, converts the received output light into an output light intensity signal, which is an electrical signal corresponding to the intensity of the output light, and converts the converted output light intensity signal into light. The signal is supplied to the signal amplifier 87. The optical signal amplifier 87 amplifies the output light intensity signal supplied from the light receiving unit 137 and supplies the amplified output light intensity signal to the DSP 89 and the APC amplifier 84.

  Further, the DSP 89 performs predetermined processing such as A / D conversion and gain correction processing on the output light intensity signal supplied from the optical signal amplifier 87, and the value of the output light intensity signal subjected to the predetermined processing is sent to the microcomputer 81. Supply.

  In step S <b> 97, the stray light component calculation unit 242 of the calculation unit 222 calculates a stray light predicted value based on the value of the output light intensity signal supplied from the DSP 89 and the coefficient of the offset function acquired from the memory 92. For example, the stray light component calculation unit 242 of the calculation unit 222 substitutes the value of the output light intensity signal supplied from the DSP 89 into the offset function obtained based on the coefficient of the offset function acquired from the memory 92, thereby stray light prediction. Calculate the value.

  Therefore, for example, when the offset function obtained based on the coefficient of the offset function is an offset function as shown by the straight line M1 in FIG. 2 and the value of the output light intensity signal supplied from the DSP 89 is P1, The stray light prediction value V1 is obtained by substituting the value P1 of the output light intensity signal into the offset function.

  In step S98, the reflected light component calculation unit 243 of the calculation unit 222 calculates the reflected light predicted value based on the value of the received light signal supplied from the DSP 89 and the predicted stray light value calculated by the stray light component calculation unit 242 of the calculation unit 222. Is calculated. The reflected light component calculation unit 243 of the calculation unit 222 supplies the calculated reflected light predicted value and the power setting value supplied from the control unit 221 to the memory 92. The reflected light component calculation unit 243 of the calculation unit 222 supplies the reflected light predicted value and the power setting value to the memory 92, generates a signal indicating that the reflected light predicted value is calculated, and generates the generated reflected light predicted value. The calculated signal is supplied to the control unit 221.

  For example, in step S98, the reflected light component calculation unit 243 of the calculation unit 222 uses the equation (2) based on the value of the received light signal supplied from the DSP 89 and the predicted stray light component calculated by the stray light component calculation unit 242 of the calculation unit 222. By calculating 2), the reflected light prediction value is calculated.

  (Reflected light predicted value) = (Value of received light signal) − (Stray light predicted value) (2)

  In step S99, the storage area 283 of the memory 92 stores the reflected light prediction value and the power setting value supplied from the microcomputer 81.

  When a signal indicating that the reflected light prediction value has been calculated is supplied from the calculation unit 222, in step S100, the control unit 221 determines whether or not the value of the light reception signal has been measured with all predetermined power setting values. Determine. If it is determined in step S100 that measurement has not been performed for all predetermined power setting values, the values of the received light signals have not been measured for all power setting values, so the process returns to step S91 and described above. Repeat the process.

  On the other hand, if it is determined in step S100 that the measurement has been performed with all the predetermined power setting values, since the values of the received light signals have been measured for all the power setting values, the process ends.

  In this way, the optical disk drive 61 calculates the stray light prediction value based on the offset function coefficient and the output light intensity signal value. Then, the optical disk drive 61 calculates a reflected light predicted value based on the value of the received light signal and the calculated stray light predicted value.

  Thus, by calculating the stray light predicted value based on the coefficient of the offset function and the value of the output light intensity signal, the optical disc driving device 61 can more accurately determine the magnitude of the reflected light component with respect to the value of the output light intensity signal. Can be determined (measured).

  With reference to the flowchart of FIG. 18, the power setting value selection process corresponding to the process of step S66 of FIG. 16 will be described.

  In step S131, the control unit 221 generates and generates a power signal for emitting light at a predetermined laser power (read power) that is emitted when reading data recorded on the optical disc 62. The power signal is supplied to the APC amplifier 84. The APC amplifier 84 generates an output control signal based on the power signal supplied from the microcomputer 81 and the output light intensity signal supplied from the optical signal amplifier 87, and supplies the generated output control signal to the LDD 85.

  In step S <b> 132, the LDD 85 generates a drive signal for emitting light with read power based on the output control signal supplied from the APC amplifier 84, and supplies the generated drive signal to the optical pickup 86.

  In step S133, the light source 132 emits a laser (light) based on the drive signal supplied from the LDD 85, and irradiates the optical disc 62 with the laser.

  Since each of the processing from step S134 to step S136 is the same as each of the processing from step S94 to step S96 in FIG.

  In step S <b> 137, the stray light component calculation unit 242 of the calculation unit 222 calculates a stray light predicted value based on the value of the output light intensity signal supplied from the DSP 89 and the coefficient of the offset function acquired from the memory 92. For example, the stray light component calculation unit 242 of the calculation unit 222 substitutes the value of the output light intensity signal supplied from the DSP 89 into the offset function obtained based on the coefficient of the offset function acquired from the memory 92, thereby stray light prediction. Calculate the value.

  In step S138, the reflected light component calculation unit 243 of the calculation unit 222 calculates the reflected light predicted value based on the value of the received light signal supplied from the DSP 89 and the predicted stray light component calculated by the stray light component calculation unit 242 of the calculation unit 222. Is calculated.

  For example, in step S 138, the reflected light component calculation unit 243 of the calculation unit 222 uses the equation (2) based on the value of the received light signal supplied from the DSP 89 and the predicted stray light component calculated by the stray light component calculation unit 242 of the calculation unit 222. By calculating 2), the reflected light prediction value is calculated.

  In step S139, the difference calculation unit 244 of the calculation unit 222 selects the optimum power setting value when data is recorded on the optical disc 62 based on the reflected light predicted value calculated by the reflected light component calculation unit 243 of the calculation unit 222. Select. The calculation unit 222 stores the optimum laser power setting value selected by the difference calculation unit 244 of the calculation unit 222, and the process ends.

  For example, when the optical disc driving device 61 changes the recording power and records data on the optical disc 62 (when trial writing is performed), the difference calculation unit 244 of the calculation unit 222 reproduces the data recorded on the optical disc 62. Each of the predicted reflected light values corresponding to each power setting value, calculated by the reflected light component calculation unit 243 of the calculation unit 222 based on the value of the received light signal obtained by doing, and a predetermined value determined in advance And the power setting value corresponding to the predicted reflected light value with the smallest calculated difference is selected as the power setting value for setting the optimum laser recording power.

  Therefore, for example, when the optical disk drive 61 emits light of each of the recording power specified by the power setting value B1, the power setting value B2, and the power setting value B3 and performs trial writing on the optical disk 62, The reflected light component calculation unit 243 of the calculation unit 222 performs each of the power setting value B1, the power setting value B2, and the power setting value B3 based on the value of the received light signal obtained by reproducing the data recorded on the optical disc 62. For each, a reflected light predicted value H1, a reflected light predicted value H2, and a reflected light predicted value H3 at the time of reproduction are calculated.

  Then, the difference calculation unit 244 of the calculation unit 222 calculates a difference between each of the calculated reflected light predicted value H1, the reflected light predicted value H2, and the reflected light predicted value H3 and a predetermined value that is determined in advance. . Here, for example, when the difference between the reflected light predicted value H1 and a predetermined value is the smallest among the calculated differences, the difference calculating unit 244 of the calculating unit 222 calculates the reflected light predicted value. The power setting value B1 corresponding to H1 is selected as the power setting value for setting the optimum laser recording power.

  In this way, the optical disk drive 61 selects an optimum power setting value when recording data on the optical disk 62.

  Thus, when data is recorded on the optical disc 62, the optimum power setting value can be selected by calculating the predicted reflected light value when the light is emitted with each power setting value.

  With reference to the flowchart of FIG. 19, the power correction process by the optical disk drive 61 will be described. Note that the processing from step S161 to step S164 is the same as the processing from step S61 to step S64 in FIG.

  In step S165, the control unit 221 generates a power signal stored in the calculation unit 222 to emit light at the laser power determined by the optimum power setting value, and the generated power signal is sent to the APC amplifier 84. Supply. The APC amplifier 84 generates an output control signal based on the power signal supplied from the microcomputer 81 and the output light intensity signal supplied from the optical signal amplifier 87, and supplies the generated output control signal to the LDD 85.

  In step S166, the control unit 221 supplies data to be recorded on the optical disc 62 to the DSP 89. The DSP 89 modulates the data supplied from the control unit 221 by a method such as an EFM method, and supplies the modulated data to the LDD 85.

  In step S167, the LDD 85 generates a drive signal for emitting light based on the output control signal supplied from the APC amplifier 84 and the data supplied from the DSP 89, and sends the generated drive signal to the optical pickup 86. Supply.

  In step S <b> 168, the light source 132 emits a laser based on the drive signal supplied from the LDD 85 and records data on the optical disk 62.

  In step S169, the optical disc driving device 61 performs a difference calculation process, and the power correction process ends. Although details of the difference calculation process will be described later, in the difference calculation process, the optical disc driving device 61 records the reflected light predicted value of the return light and the optimum power setting value stored in the memory 92. The difference from the reflected light predicted value at the time is calculated, and the recording power is corrected based on the calculated difference.

  As described above, the optical disk drive 61 records data on the optical disk 62. Then, the difference between the reflected light predicted value of the return light and the reflected light predicted value at the optimum power setting value is calculated, and the recording power is corrected based on the calculated difference.

  As described above, the difference between the reflected light predicted value of the return light and the reflected light predicted value at the optimum power setting value is calculated, and the recording power is corrected based on the calculated difference. The power of the output laser can be corrected.

  A difference calculation process corresponding to the process of step S169 in FIG. 19 will be described with reference to the flowchart in FIG. Note that the processing from step S191 to step S193 is the same as the processing from step S94 to step S96 in FIG.

  In step S 194, the stray light component calculation unit 242 of the calculation unit 222 calculates a stray light predicted value based on the value of the output light intensity signal supplied from the DSP 89 and the coefficient of the offset function acquired from the memory 92. For example, the stray light component calculation unit 242 of the calculation unit 222 substitutes the value of the output light intensity signal supplied from the DSP 89 into the offset function obtained based on the coefficient of the offset function acquired from the memory 92, thereby stray light prediction. Calculate the value.

  In step S195, the reflected light component calculation unit 243 of the calculation unit 222 calculates the reflected light predicted value based on the value of the received light signal supplied from the DSP 89 and the predicted stray light value calculated by the stray light component calculation unit 242 of the calculation unit 222. Is calculated.

  For example, in step S 195, the reflected light component calculation unit 243 of the calculation unit 222 uses the formula ( By calculating 2), the reflected light prediction value is calculated.

  In step S196, the difference calculation unit 244 of the calculation unit 222 records the reflected light predicted value calculated by the reflected light component calculation unit 243 of the calculation unit 222 and the optimum power setting value stored in the memory 92 at the time of recording. The difference between the reflected light predicted value and the calculated difference is supplied to the control unit 221.

  For example, when the optical disk drive 61 emits light of the recording power specified by the power setting value B21, the power setting value B22, and the power setting value B23 and performs trial writing on the optical disk 62, FIG. In the process of step S98, the reflected light component calculation unit 243 of the calculation unit 222, based on the value of the received light signal obtained when data is recorded on the optical disc 62, the power setting value B21, the power setting value B22, and For each power setting value B23, a reflected light predicted value H21, reflected light predicted value H22, and reflected light predicted value H23 during recording are calculated.

  The reflected light component calculation unit 243 of the calculation unit 222 includes the calculated reflected light predicted value H21, reflected light predicted value H22, and reflected light predicted value H23, the power setting value B21, the power setting value B22, and the power setting value, respectively. Each of B23 is supplied to the memory 92. The memory 92 includes a reflected light predicted value H21, a reflected light predicted value H22, and a reflected light predicted value H23 supplied from the microcomputer 81, and a power set value B21, a power set value B22, and a power set value B23, respectively. Remember.

  Then, by reproducing the test-written data recorded on the optical disc 62, for example, when the power setting value B21 is selected as the optimum power setting value, the calculation is performed when data is recorded on the optical disc 62. The difference calculation unit 244 of the unit 244 includes a reflected light prediction value H21 stored in the memory 92 and a reflected light prediction value at the time of recording with respect to the power setting value B21 calculated in the process of step S195 (hereinafter, reflected light prediction). The difference from the value (referred to as value H31) is calculated by calculating equation (3).

  (Difference) = (Reflected light predicted value H21) − (Reflected light predicted value H31) (3)

  In step S197, the APC amplifier 84 corrects the recording power by the difference calculated by the microcomputer 81, and the process ends. That is, the control unit 221 generates a power signal so as to increase or decrease the recording power by the difference supplied from the calculation unit 222, and supplies the generated power signal to the APC amplifier 84. The APC amplifier 84 generates an output control signal based on the power signal supplied from the microcomputer 81 and the output light intensity signal supplied from the optical signal amplifier 87, and supplies the generated output control signal to the LDD 85.

  Therefore, for example, when the difference value supplied from the calculation unit 222 is K1 and K1 is larger than 0, the control unit 221 generates a power signal so that the recording power is increased by K1, and K1 is When it is smaller than 0, the control unit 221 generates a power signal so as to decrease the recording power by the magnitude of K1 (the absolute value of K1).

  In this way, the optical disk drive 61 calculates the difference between the reflected light predicted value of the return light and the reflected light predicted value stored in the memory 92 at the optimum power setting value, and based on the calculated difference. Then, correct the recording power.

  In this way, the difference between the reflected light predicted value of the return light and the reflected light predicted value stored in the memory 92 at the optimum power setting value is calculated, and the recording power is corrected based on the calculated difference. This makes it possible to correct the power of the laser that emits light (outputs) more accurately.

  As described above, since the optical disk drive apparatus calculates the offset function, the magnitude of the stray light component corresponding to the intensity of the emitted light can be measured more accurately. In addition, since the predicted stray light value corresponding to the intensity of the emitted light is calculated, the power of the emitted light can be set more accurately during recording or reproduction.

  In addition, it is also possible to arrange | position the light-receiving part which receives output light in the position shown in FIG. 21 or FIG. In FIG. 21 and FIG. 22, the same reference numerals are given to the portions corresponding to those in FIG.

  In FIG. 21, arrows indicate the optical paths of light. The light receiving unit 301 that receives the output light is disposed on the end surface 151 of the integrated substrate 131 so as to be adjacent to the end surface of the prism 134. Part of the light emitted from the light source 132 (stray light) passes through the reflecting surface 152 of the prism 134 and enters the prism 134. The light incident on the prism 134 is incident on the end surface 151 of the integrated substrate 131. The light receiving unit 301 receives a part of the light incident on the end surface 151 of the integrated substrate 131. The light receiving unit 301 converts the received light into an output light intensity signal that is an electric signal corresponding to the light reception intensity of the light.

  In FIG. 22, the arrow indicates the optical path of light. The beam splitter 321 is disposed between the collimator lens 135 and the reflecting surface 152 of the prism 134. Further, the light receiving unit 322 is disposed in the vicinity of the beam splitter 321.

  The light emitted from the light source 132 is reflected by the reflecting surface 152 of the prism 134 and enters the beam splitter 321. The light incident on the beam splitter 321 is separated and enters the collimator lens 135 or the light receiving unit 322.

  The light receiving unit 322 receives the light separated by the beam splitter 321 and incident on the light receiving unit 322 as output light. The light receiving unit 322 converts the received light into an output light intensity signal that is an electrical signal corresponding to the light reception intensity of the light. On the other hand, the light separated by the beam splitter 321 and incident on the collimator lens 135 is irradiated onto the optical disc 62 through the objective lens 136.

  Further, although it has been described that the output light is received and the stray light predicted value is calculated using the value of the output light intensity signal, the stray light predicted value may be calculated using the power setting value. Hereinafter, with reference to FIG. 23 to FIG. 25, a process executed by the optical disc driving device 61 when the predicted stray light value is calculated using the power setting value will be described.

  First, an offset function calculation process performed by the optical disc driving device 61 will be described with reference to the flowchart of FIG. Since each of the processing from step S231 to step S235 is the same as each of the processing from step S31 to step S35 in FIG. 14, the description thereof is omitted.

  In step S 236, the DSP 89 performs predetermined processing on the stray light reception signal supplied from the servo matrix amplifier 88 and supplies the value of the stray light reception signal to the memory 92. Further, the control unit 221 supplies the power setting value to the memory 92. The storage area 281 of the memory 92 stores the value of the stray light reception signal supplied from the DSP 89 and the power setting value supplied from the microcomputer 81.

  For example, in step S 236, the DSP 89 performs processing such as A / D conversion and gain correction processing on the stray light reception signal supplied from the servo matrix amplifier 88, and supplies the value of the stray light reception signal to the memory 92. The control unit 221 supplies the power setting value to the memory 92. The storage area 281 of the memory 92 stores the value of the stray light reception signal supplied from the DSP 89 and the power setting value supplied from the microcomputer 81.

  In step S237, the control unit 221 determines whether or not the value of the stray light reception signal has been measured with all predetermined power setting values.

  If it is determined in step S237 that measurement has not been performed for all predetermined power setting values, the stray light reception signal value has not been measured for all power setting values, and the procedure goes to step S231. Return.

  On the other hand, if it is determined in step S237 that the measurement has been performed with all the predetermined power setting values, the values of the stray light reception signal are measured with all the power setting values, so the control unit 221 calculates the offset function. And a signal for calculating the generated offset function is supplied to the calculation unit 222. Then, the process proceeds to step S238, and when the signal indicating that the offset function is calculated is supplied from the control unit 221, the offset function calculation unit 241 of the calculation unit 222 stores the value and power of the stray light reception signal stored in the memory 92. An offset function is calculated based on the set value. The offset function calculation unit 241 of the calculation unit 222 supplies the calculated offset function coefficient to the memory 92, and the process ends.

  For example, the offset function calculation unit 241 of the calculation unit 222 calculates the coefficient of the polynomial shown in Equation (1) by the least square method based on the value of the stray light reception signal and the power setting value stored in the memory 92. To calculate the offset function. In this case, X in Equation (1) is a power setting value.

  In this way, the optical disk drive 61 calculates an offset function.

  Thus, by calculating the offset function, the magnitude of the stray light component corresponding to the power setting value can be obtained more accurately.

  Next, the reflected light predicted value calculation processing by the optical disc driving device 61 will be described with reference to the flowchart of FIG. Note that the processing from step S261 to step S265 is the same as the processing from step S91 to step S95 in FIG.

  In step S266, the stray light component calculation unit 242 of the calculation unit 222 acquires the power setting value from the control unit 221, and calculates the stray light prediction value based on the acquired power setting value and the coefficient of the offset function acquired from the memory 92. To do. For example, the stray light component calculation unit 242 of the calculation unit 222 substitutes the power value indicated by the power setting value acquired from the control unit 221 into the offset function obtained based on the coefficient of the offset function acquired from the memory 92. To calculate a stray light prediction value.

  In step S267, the reflected light component calculation unit 243 of the calculation unit 222 calculates the reflected light predicted value based on the value of the received light signal supplied from the DSP 89 and the stray light predicted value calculated by the stray light component calculation unit 242 of the calculation unit 222. Is calculated. The reflected light component calculation unit 243 of the calculation unit 222 supplies the calculated reflected light predicted value and the power setting value acquired from the control unit 221 to the memory 92. The reflected light component calculation unit 243 of the calculation unit 222 supplies the reflected light predicted value and the power setting value to the memory 92, generates a signal indicating that the reflected light predicted value is calculated, and generates the generated reflected light predicted value. The calculated signal is supplied to the control unit 221.

  For example, in step S267, the reflected light component calculation unit 243 of the calculation unit 222 calculates the formula ( By calculating 2), the reflected light prediction value is calculated.

  In step S268, the storage area 283 of the memory 92 stores the reflected light prediction value and the power setting value supplied from the microcomputer 81.

  When the signal indicating that the reflected light prediction value has been calculated is supplied from the calculation unit 222, in step S269, the control unit 221 determines whether or not the value of the light reception signal has been measured with all predetermined power setting values. Determine. If it is determined in step S269 that measurement has not been performed with all predetermined power setting values, the values of the received light signals have not yet been measured for all power setting values, so the process returns to step S261 and described above. Repeat the process.

  On the other hand, if it is determined in step S269 that the measurement has been performed with all the predetermined power setting values, since the values of the received light signals have been measured for all the power setting values, the process ends.

  In this way, the optical disk drive 61 calculates the stray light prediction value based on the offset function coefficient and the power setting value. Then, the optical disk drive 61 calculates a reflected light predicted value based on the value of the received light signal and the calculated stray light predicted value.

  As described above, by calculating the stray light predicted value based on the coefficient of the offset function and the power setting value, the optical disc driving device 61 can more accurately calculate the magnitude of the reflected light component with respect to the power setting value. .

  With reference to the flowchart of FIG. 25, the difference calculation process by the optical disk drive 61 will be described. Note that the processing from step S294 to step S296 is the same as the processing from step S195 to step S197 in FIG.

  In step S <b> 291, the light receiving unit 137 receives the return light, converts the received return light into an electric signal corresponding to the intensity of the light, and supplies the converted electric signal to the optical signal amplifier 87. Then, the optical signal amplifier 87 amplifies the electrical signal supplied from the light receiving unit 137 and supplies the amplified electrical signal to the servo matrix amplifier 88. In this case, since the focus servo is turned on, the light emitted from the light source 132 is reflected by the optical disc 62, passes through the reflecting surface 152 of the prism 134, and enters the light receiving unit 137. Therefore, the return light received by the light receiving unit 137 includes light reflected by the optical disk 62 (reflected light) and stray light as return light components.

  In step S292, the servo matrix amplifier 88 generates a light reception signal based on the electrical signal supplied from the optical signal amplifier 87, and supplies the generated light reception signal to the DSP 89. The DSP 89 performs predetermined processing such as A / D conversion, gain correction processing, and decoding on the light reception signal supplied from the servo matrix amplifier 88, and the value of the light reception signal subjected to the predetermined processing is sent to the microcomputer 81. Supply.

  In step S293, the stray light component calculation unit 242 of the calculation unit 222 acquires the power setting value from the control unit 221, and calculates the stray light predicted value based on the acquired power setting location and the coefficient of the offset function acquired from the memory 92. To do. For example, the stray light component calculation unit 242 of the calculation unit 222 substitutes the power value indicated by the power setting value acquired from the control unit 221 into the offset function obtained based on the coefficient of the offset function acquired from the memory 92. To calculate a stray light prediction value.

  In this way, the optical disk drive 61 calculates the difference between the reflected light predicted value of the return light and the reflected light predicted value stored in the memory 92 at the optimum power setting value, and based on the calculated difference. Then, correct the recording power.

  In this way, the difference between the reflected light predicted value of the return light and the reflected light predicted value stored in the memory 92 at the optimum power setting value is calculated, and the recording power is corrected based on the calculated difference. This makes it possible to correct the power of the laser that emits light (outputs) more accurately.

  Next, a second embodiment to which the present invention is applied will be described.

  FIG. 26 is a block diagram showing an example of the configuration of an optical disk drive device to which the present invention is applied. In the figure, portions corresponding to those in the case of FIG. 4 are denoted by the same reference numerals, and the description will be omitted.

  The optical disk drive reproduces data recorded on the optical disk 62 mounted on the optical disk drive. Further, the optical disc driving device records desired data on the optical disc 62 mounted on the optical disc driving device. Further, a PC (Personal Computer) 352 is connected to the optical disc driving apparatus, and the PC 352 calculates an offset function and supplies the calculated offset function coefficient to the optical disc driving apparatus.

  The optical disk drive includes a spindle motor drive circuit 82, a spindle motor 83, an APC amplifier 84, an LDD 85, an optical pickup 86, an optical signal amplifier 87, a servo matrix amplifier 88, a drive amplifier 90, an actuator 91, a microcomputer 351, a DSP 353, and a memory. 354.

  The microcomputer 351 (hereinafter also referred to as a microcomputer 351) generates a signal for turning on or off the focus servo, and supplies the DSP 353 with a signal for turning on or off the generated focus servo. The microcomputer 351 supplies data to be recorded on the optical disc 62 to the DSP 353.

  The microcomputer 351 generates a power signal that specifies the power of the laser that emits light, and supplies the generated power signal to the APC amplifier 84. The microcomputer 351 generates a signal indicating that the optical disk 62 is rotationally driven, and supplies the generated signal indicating that the optical disk 62 is rotationally driven to the spindle motor driving circuit 82.

  The microcomputer 351 calculates the reflected light prediction value based on the offset function coefficient stored in the memory 354 and the value of the output light intensity signal supplied from the DSP 353. The microcomputer 351 supplies the calculated reflected light predicted value and power setting value to the memory 354.

  The microcomputer 351 selects an optimum laser power setting value when data is recorded on the optical disc 62 based on the value of the received light signal supplied from the DSP 353. The microcomputer 351 temporarily stores the selected power setting value.

  The microcomputer 351 calculates the reflected light predicted value based on the value of the output light intensity signal supplied from the DSP 353 and the coefficient of the offset function stored in the memory 354. The microcomputer 351 calculates the difference between the calculated reflected light predicted value and the reflected light predicted value at the optimum power setting value stored in the memory 354, and the laser power specified by the power signal is calculated. The power signal is generated so as to increase or decrease by the difference.

  The PC 352 calculates an offset function based on the value of the stray light reception signal and the value of the output light intensity signal supplied from the DSP 353. The PC 352 supplies the calculated offset function coefficient to the memory 354.

  The DSP 353 performs predetermined processing such as gain correction processing and A / D conversion processing on the stray light reception signal supplied from the servo matrix amplifier 88 and supplies the PC 352 with the value of the processed stray light reception signal. The DSP 353 performs predetermined processing such as gain correction processing and A / D conversion processing on the output light intensity signal supplied from the optical signal amplifier 87, and sends the processed value of the output light intensity signal to the microcomputer 351 or the PC 352. Supply.

  The DSP 353 performs predetermined processing such as decoding, gain correction processing, and A / D conversion processing on the light reception signal supplied from the servo matrix amplifier 88, and supplies the processed light reception signal value to the microcomputer 351.

  The DSP 353 modulates the data supplied from the microcomputer 351 by a predetermined method, and supplies the modulated data to the LDD 85.

  The memory 354 is composed of, for example, a nonvolatile memory such as a semiconductor memory, and stores a coefficient of an offset function supplied from the PC 352. The memory 354 stores the reflected light prediction value, power setting value, program, or data supplied from the microcomputer 351. The memory 354 supplies the stored value of the output light intensity signal value offset function coefficient, reflected light predicted value, power setting value, program, or data to the microcomputer 351.

  FIG. 27 is a block diagram illustrating a functional configuration of the PC 352. A CPU (Central Processing Unit) 381 executes various processes according to a program recorded in a ROM (Read Only Memory) 382 or a recording unit 388. A RAM (Random Access Memory) 383 appropriately stores programs executed by the CPU 381 and data. The CPU 381, ROM 382, and RAM 383 are connected to each other by a bus 384.

  An input / output interface 385 is also connected to the CPU 381 via the bus 384. The input / output interface 385 is connected to an input unit 386 including a keyboard, a mouse, and a switch, and an output unit 387 including a display, a speaker, and a lamp. The CPU 381 executes various processes in response to a command input from the input unit 386.

  The recording unit 388 connected to the input / output interface 385 is configured by, for example, a hard disk and records programs executed by the CPU 381 and various data. The communication unit 389 communicates with an external device via a communication network such as the Internet or other networks.

  Alternatively, the program may be acquired via the communication unit 389 and recorded in the recording unit 388.

  The drive 390 connected to the input / output interface 385 drives the magnetic disk 411, the optical disk 412, the magneto-optical disk 413, the semiconductor memory 414, or the like when they are loaded, and programs and data recorded there. Get etc. The acquired program and data are transferred to the recording unit 388 and recorded as necessary.

  FIG. 28 is a block diagram illustrating a functional configuration of the PC 352.

  The PC 352 is configured to include a measurement value recording unit 411, a control unit 442, and an offset function calculation unit 443.

  The measurement value recording unit 441 records the value of the stray light reception signal and the value of the output light intensity signal supplied from the DSP 353. The measurement value recording unit 441 supplies the recorded stray light reception signal value and output light intensity signal value to the offset function calculation unit 443.

  When the value of the stray light reception signal is measured at all power setting values that are determined in advance, the control unit 442 generates a signal that the value of the stray light reception signal is measured at all the power setting values. Then, a signal indicating that measurement is performed for all generated power setting values is supplied to the offset function calculation unit 443.

  When the offset function 443 is supplied from the control unit 442 with a signal indicating that measurement has been performed for all power setting values, the value of the stray light reception signal and the value of the output light intensity signal supplied from the measurement value recording unit 441 are provided. Based on the above, an offset function is calculated, and the coefficient of the calculated offset function is supplied to the memory 354.

  FIG. 29 is a block diagram illustrating a functional configuration of the microcomputer 351.

  The microcomputer 351 is configured to include a control unit 471 and a calculation unit 472.

  The control unit 471 generates a signal for turning on or off the focus servo, and supplies the DSP 353 with a signal for turning on or off the generated focus servo. The control unit 471 supplies data to be recorded on the optical disc 62 to the DSP 353.

  The control unit 471 generates a power signal that specifies the power of the laser that emits light, and supplies the generated power signal to the APC amplifier 84. The control unit 471 generates a signal indicating that the optical disk 62 is rotationally driven, and supplies the generated signal indicating that the optical disk 62 is rotationally driven to the spindle motor driving circuit 82.

  The calculation unit 472 calculates the difference between the stray light signal value, the reflected light predicted value, and the reflected light predicted value. The calculation unit 472 is configured to include a stray light component calculation unit 491, a reflected light component calculation unit 492, and a difference calculation unit 493. Note that the stray light component calculation unit 491, the reflected light component calculation unit 492, and the difference calculation unit 493 of the calculation unit 472 are respectively the stray light component calculation unit 242, the reflected light component calculation unit 243, and the difference calculation unit 244 in FIG. Since it is the same as each, description thereof will be omitted as appropriate.

  The difference calculation unit 493 of the calculation unit 472 is the difference between the reflected light predicted value calculated by the reflected light component calculation unit 492 of the calculation unit 472 and the reflected light predicted value at the optimum power setting value stored in the memory 354. And the calculated difference is supplied to the control unit 471.

  The control unit 471 generates a power signal so that the laser power specified by the power signal increases or decreases by the difference supplied from the calculation unit 472.

  The stray light measurement process will be described with reference to the flowchart of FIG. Note that the processing from step S331 to step S333 is the same as the processing from step S11 to step S13 in FIG.

  In step S334, the optical disk drive and the PC 352 perform an offset function calculation process. Although details of the offset function calculation process will be described later, in the offset function calculation process, the optical disc driving device and the PC 352 calculate an offset function based on the value of the stray light reception signal and the value of the output light intensity signal, The calculated offset function coefficient is supplied to the memory 354.

  In step S335, the memory 354 stores the coefficient of the offset function supplied from the PC 352, and the stray light measurement process ends.

  In this way, the optical disc driving apparatus and the PC 352 calculate the offset function and store the calculated offset function coefficient.

  Thus, by calculating the offset function, the magnitude of the stray light component corresponding to the intensity of the emitted light can be obtained more accurately.

  The offset function calculation process corresponding to the process of step S334 in FIG. 30 will be described with reference to the flowchart in FIG. Note that the processing from step S361 to step S366 is the same as the processing from step S31 to step S36 in FIG. 14, and a description thereof will be omitted.

  In step S367, the DSP 353 performs predetermined processing on the stray light reception signal supplied from the servo matrix amplifier 88 and the output light intensity signal supplied from the optical signal amplifier 87, and calculates the value of the stray light reception signal and the output light intensity signal. The value is supplied to the PC 352.

  For example, in step S367, the DSP 353 performs processing such as A / D conversion and gain correction processing on the stray light reception signal supplied from the servo matrix amplifier 88 and the output light intensity signal supplied from the optical signal amplifier 87, and stray light. The value of the received light signal and the value of the output light intensity signal are supplied to the PC 352.

  In step S368, the control unit 442 determines whether or not the value of the stray light reception signal has been measured with all predetermined power setting values.

  If it is determined in step S368 that measurement has not been performed for all predetermined power setting values, the stray light reception signal value has not been measured for all power setting values, and the procedure goes to step S361. Return.

  On the other hand, if it is determined in step S368 that the measurement has been performed with all the predetermined power setting values, the values of the stray light reception signal have been measured for all the power setting values. Therefore, the process proceeds to step S369, and the control unit 442 Then, a signal indicating that the value of the stray light reception signal is measured at all the power setting values is generated, and a signal indicating that the value is measured at all the generated power setting values is supplied to the offset function calculating unit 443.

  In step S370, the offset function calculation unit 443 calculates an offset function based on the stray light reception signal value and the output light intensity signal value supplied from the measurement value recording unit 441. The offset function calculation unit 443 supplies the calculated coefficient of the offset function to the memory 354, and the process ends.

  For example, the offset function calculation unit 443 calculates the coefficient of the polynomial shown in Expression (1) by the least square method based on the value of the stray light reception signal and the value of the output light intensity signal supplied from the measurement value recording unit 441. Thus, an offset function is calculated.

  In this way, the optical disc driving apparatus and the PC 352 calculate the offset function.

  Thus, by calculating the offset function, the magnitude of the stray light component corresponding to the intensity of the emitted light can be obtained more accurately.

  As described above, since the optical disk drive apparatus calculates the offset function, the magnitude of the stray light component corresponding to the intensity of the emitted light can be measured more accurately. Further, since the magnitude of the stray light component corresponding to the intensity of the emitted light is calculated, the power of the emitted light can be set more accurately during recording or reproduction.

  According to the present invention, the power of the laser that emits light can be set because the power of the laser is designated. According to the present invention, since the offset function is calculated, the magnitude of the stray light component corresponding to the intensity of the emitted light can be measured more accurately. Furthermore, according to the present invention, since the magnitude of the stray light component corresponding to the intensity of the emitted light is calculated, the power of the emitted light can be set more accurately during recording or reproduction. .

  The series of processes described above can be executed by hardware, but can also be executed by software. When a series of processing is executed by software, a program constituting the software may execute various functions by installing a computer incorporated in dedicated hardware or various programs. For example, it is installed from a recording medium in a general-purpose personal computer or the like.

  As shown in FIG. 4 or FIG. 27, this recording medium is a magnetic disk 111 (including a flexible disk) or a magnetic disk on which a program is recorded, which is distributed to provide a program to a user separately from a computer. 411, optical disk 112 or optical disk 412 (including CD-ROM (Compact Disc-Read Only Memory), DVD (Digital Versatile Disc)), magneto-optical disk 113 or magneto-optical disk 413 (MD (Mini-Disc) (trademark)) A ROM 383 storing a program and a recording unit 388 provided to a user in a state of being incorporated in a computer in advance, in addition to a package medium including the semiconductor memory 114 or the semiconductor memory 414. The hard disk included in

  The program for executing the series of processes described above is installed in a computer via a wired or wireless communication medium such as a local area network, the Internet, or digital satellite broadcasting via an interface such as a router or a modem as necessary. You may be made to do.

  Further, in the present specification, the step of describing the program stored in the recording medium is not limited to the processing performed in time series according to the described order, but is not necessarily performed in time series. It also includes processes that are executed individually.

  In the present specification, the term “system” represents the entire apparatus constituted by a plurality of apparatuses.

It is a figure which shows the structure of the conventional optical pick-up. It is a figure which shows the magnitude | size of the light reception signal with respect to the intensity | strength of the light-emitting laser, and a stray light light reception signal. It is a figure which shows the magnitude | size of a light reception signal when changing the intensity | strength of the light to light-emit. It is a block diagram which shows the example of a structure of the optical disk drive device to which this invention is applied. It is a figure which shows the structure of an optical pick-up. It is a figure explaining an optical pick-up. It is a figure which shows the end surface of the light-receiving side of a light-receiving part. It is a figure which shows the end surface of the light-receiving side of a light-receiving part. It is a figure explaining the stray light which an optical pick-up receives. It is a figure explaining the stray light which an optical pick-up receives. It is a block diagram which shows the structure of the function of a microcomputer. It is a block diagram which shows the structure of the function of memory. It is a flowchart explaining the process of a stray light measurement. It is a flowchart explaining the process of offset function calculation. It is a figure explaining the power of the light which an optical disk drive device light-emits. It is a flowchart explaining the process of test writing. It is a flowchart explaining the process of reflected light prediction value calculation. It is a flowchart explaining the process of a power setting value selection. It is a flowchart explaining the process of power correction. It is a flowchart explaining the process of difference calculation. It is a figure which shows the structure of an optical pick-up. It is a figure which shows the structure of an optical pick-up. It is a flowchart explaining the process of offset function calculation. It is a flowchart explaining the process of reflected light prediction value calculation. It is a flowchart explaining the process of difference calculation. It is a block diagram which shows the example of a structure of the optical disk drive device to which this invention is applied. It is a block diagram which shows the example of a structure of PC. It is a block diagram which shows the structure of the function of PC. It is a block diagram which shows the structure of the function of a microcomputer. It is a flowchart explaining the process of a stray light measurement. It is a flowchart explaining the process of offset function calculation.

Explanation of symbols

  61 optical disk drive, 81 microcomputer, 85 LDD, 86 optical pickup, 89 DSP, 92 memory, 111 magnetic disk, 112 optical disk, 113 magneto-optical disk, 114 semiconductor memory, 132 light source, 133 light receiving unit, 137-1, 137 -2,137 light receiving unit, 221 control unit, 222 calculating unit, 241 offset function calculating unit, 242 stray light component calculating unit, 243 reflected light component calculating unit, 244 difference calculating unit, 301 light receiving unit, 321 beam splitter, 322 light receiving unit , 351 microcomputer, 352 PC, 353 DSP, 354 memory, 381 CPU, 382 ROM, 383 RAM, 388 recording unit, 411 magnetic disk, 412 optical disk, 413 light Magnetic disk, 414 semiconductor memory, 441 measurement value recording unit, 442 control unit, 443 offset function calculation unit, 471 control unit, 472 calculation unit, 491 stray light component calculation unit, 492 reflected light component calculation unit, 493 difference calculation unit

Claims (8)

In an optical disk drive for driving an optical disk,
A first value indicating the intensity of light emitted to the optical disc and data recorded on the optical disc, or when data is recorded on the optical disc, the optical disc is irradiated and reflected. A second value indicating the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light applied to the optical disk received by the light receiving means that receives the reflected light. A function calculating means for calculating a function representing a correspondence relationship between the first value and the plurality of second values;
When reading data recorded on the optical disc or recording data on the optical disc, a third value indicating the intensity of light received by the light receiving means when the intensity of emitted light is changed with time. And a reflected light intensity calculating means for calculating a fourth value indicating the intensity of the reflected light received by the light receiving means using the function. A stray light intensity calculating means for calculating the intensity of the stray light for each of a plurality of intensities, which is the intensity of light irradiated to the optical disc using the function
The optical disk drive device according to claim 1, wherein the reflected light intensity calculation unit calculates the fourth value based on the third value and the calculated intensity of the stray light. Difference calculating means for calculating a difference between the fourth value obtained in advance and the fourth value calculated by the reflected light intensity calculating means;
The correction means for correcting the intensity of the emitted light so as to increase or decrease the intensity of the emitted light by the calculated magnitude of the difference, further comprising: Optical disk drive device. In an optical disk driving method for driving an optical disk,
A first value indicating the intensity of light emitted to the optical disc and data recorded on the optical disc, or when data is recorded on the optical disc, the optical disc is irradiated and reflected. A second value indicating the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light applied to the optical disk received by the light receiving means that receives the reflected light. A function calculating step for calculating a function representing a correspondence relationship between the first value and the plurality of second values;
When reading data recorded on the optical disc or recording data on the optical disc, a third value indicating the intensity of light received by the light receiving means when the intensity of emitted light is changed with time. And a reflected light intensity calculating step of calculating a fourth value indicating the intensity of the reflected light received by the light receiving means using the function. An optical disc drive processing program for driving an optical disc,
A first value indicating the intensity of light emitted to the optical disc and data recorded on the optical disc, or when data is recorded on the optical disc, the optical disc is irradiated and reflected. A second value indicating the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light applied to the optical disk received by the light receiving means that receives the reflected light. A function calculating step for calculating a function representing a correspondence relationship between the first value and the plurality of second values;
When reading data recorded on the optical disc or recording data on the optical disc, a third value indicating the intensity of light received by the light receiving means when the intensity of emitted light is changed with time. And a reflected light intensity calculating step for calculating a fourth value indicating the intensity of the reflected light received by the light receiving means by using the function. Recording medium. In a program for causing a computer to perform an optical disc driving process for driving an optical disc,
A first value indicating the intensity of light emitted to the optical disc and data recorded on the optical disc, or when data is recorded on the optical disc, the optical disc is irradiated and reflected. A second value indicating the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light applied to the optical disk received by the light receiving means that receives the reflected light. A function calculating step for calculating a function representing a correspondence relationship between the first value and the plurality of second values;
When reading data recorded on the optical disc or recording data on the optical disc, a third value indicating the intensity of light received by the light receiving means when the intensity of emitted light is changed with time. And a reflected light intensity calculating step of calculating a fourth value indicating the intensity of the reflected light received by the light receiving means using the function. In an optical disk drive for driving an optical disk,
A first value indicating the intensity of light specified by a light intensity setting value that specifies the intensity of emitted light and data recorded on the optical disk are read or data is recorded on the optical disk. The intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light emitted by the light receiving means that receives the reflected light that is irradiated and reflected by the optical disk. A function calculating means for calculating a function representing a correspondence relationship with the second value shown based on the plurality of first values and the plurality of second values;
When reading data recorded on the optical disc or recording data on the optical disc, a third value indicating the intensity of light received by the light receiving means when the intensity of emitted light is changed with time. And a reflected light intensity calculating means for calculating a fourth value indicating the intensity of the reflected light received by the light receiving means using the function. In an optical disc driving apparatus that can be connected to a predetermined external device that exchanges data and drives an optical disc,
A first value indicating the intensity of light emitted to the optical disc and data recorded on the optical disc, or when data is recorded on the optical disc, the optical disc is irradiated and reflected. A second value indicating the intensity of only the stray light that is not reflected by the optical disk out of the emitted light corresponding to the intensity of the light applied to the optical disk received by the light receiving means that receives the reflected light. And a stray light intensity for calculating the intensity of the stray light for each of a plurality of intensities using a function supplied from the external device. A calculation means;
When reading data recorded on the optical disc or recording data on the optical disc, a third value indicating the intensity of light received by the light receiving means when the intensity of emitted light is changed with time. And an reflected light intensity calculating means for calculating a fourth value indicating the intensity of the reflected light received by the light receiving means based on the calculated intensity of the stray light.

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