JP2005122798A - Optical disk device and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize the temperature of a light emitting element with a simple constitution. <P>SOLUTION: In an optical disk device, a power value of a laser beam emitted to an optical disk from a light emitting element is set and the light emitting element is driven, and recording and/or reproducing processing for the optical disk is performed. The device has a means for detecting the temperature of the light emitting element; and a control means in which test drive is started before recording and/or reproducing processing for the optical disk is started, from the time when the test drive is started, whenever the prescribed time elapses, the temperature detected in the above means is obtained, and when a difference between the obtained temperature and temperature obtained the prescribed time before the temperature is obtained becomes within the prescribed range, the test drive is finished, and recording and/or reproducing processing for the optical disk is started. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical disc apparatus and a control method thereof.

  2. Description of the Related Art In an optical disc apparatus that performs recording or reproduction processing using laser light emitted from a laser diode (hereinafter referred to as LD (Laser Diode)) to an optical disc, a front monitor diode (hereinafter referred to as FMD) on the front side of the LD. (Referred to as “Front Monitor Diode”), the power value (read power value) of the LD output at the time of reproduction and the power value (write power value) of the LD output at the time of recording are constant. Thus, servo control by APC (Automatic Power Control) is executed.

  The LD generates heat when the laser beam is emitted by the current supplied from the LD driver. This heat changes the temperature of the LD itself or the ambient temperature of the LD. Furthermore, due to this temperature change, the wavelength of the laser light emitted from the LD varies due to the temperature dependence of the oscillation wavelength in the LD. Here, on the light receiving side of the FMD, a transmission film having a wavelength dependency is usually provided so as to allow light having a predetermined wavelength to pass therethrough. (Transmissivity) varies, and the LD output detected in the FMD varies.

As described above, the LD output detected by the FMD fluctuates due to the temperature change of the LD itself or the surroundings of the LD, and as a result, the APC servo control breaks down. Will have a negative impact. Therefore, for example, as in the technique disclosed in Patent Document 1 shown below, a mechanism of an optical disc apparatus that performs drive control of the LD based on the temperature detected by the LD temperature detection means has been proposed.
JP 2001-216672-A

  By the way, a system controller or the like that controls the entire optical disc apparatus acquires the temperature detected by the above-described LD temperature detecting means in real time, and further, the LD of the LD according to the temperature to stabilize the temperature of the LD. When trying to execute the drive control in real time, it takes a long time to perform the series of processes, which is difficult to realize.

  Further, it is conceivable that the temperature of the LD itself or the ambient temperature of the LD changes rapidly after the supply of current from the LD driver to the LD is started from when the power is turned on or in a standby state, and then stabilizes. Here, when the drive control of the LD according to the temperature described above is executed in real time even during the recording or reproducing process, the LD itself itself is charged even though the system controller or the like is burdened with a considerable amount of processing. Alternatively, the effect of stabilizing the temperature around the LD may not be obtained so much.

  As described above, there is a need for a simple mechanism that performs the drive control of the LD according to the above-described temperature without reducing the performance of the entire optical disc apparatus.

  Accordingly, an object of the present invention is to provide an optical disc apparatus capable of stabilizing the temperature related to the LD with a simple mechanism while suppressing the performance degradation of the entire apparatus, and a control method thereof.

  The main present invention for solving the above-mentioned problems is an optical disc that sets a power value of laser light emitted from a light emitting element to an optical disc and drives the light emitting device to perform recording and / or reproduction processing on the optical disc. A device for detecting a temperature related to the light emitting element, and starting a test drive of the light emitting element before starting a recording or reproducing process on the optical disc, from when the test drive is started, The temperature detected by the means is acquired every time a predetermined time elapses, and a difference between the acquired temperature and a temperature acquired a predetermined time before the temperature is acquired is predetermined. Control means for terminating the test drive and starting the recording or reproducing process on the optical disc when it falls within the range.

  The optical disc apparatus according to the present invention focuses on the fact that the temperature of the light emitting element itself or its surroundings rapidly changes due to the heat generated from the light emitting element at the initial stage of driving the light emitting element. Before actually starting the recording or reproducing process, the light emitting element is test-driven in order to stabilize the temperature of the light emitting element itself or the surrounding temperature. Note that the test drive of the light emitting element is terminated under a predetermined condition so as not to be executed during the process of recording or reproducing on the optical disc. Further, in the test drive of the light emitting element, the control unit does not acquire the detected temperature in real time, but acquires the predetermined temperature every predetermined time, and the power value of the laser beam corresponding to the acquired temperature The adjustment is performed at the predetermined time instead of in real time.

  The optical disk apparatus according to the present invention can stabilize the temperature of the light emitting element itself or its surroundings while suppressing the performance degradation in the control means or the like by executing the test drive of the light emitting element. In addition, when setting the power value of the laser beam for recording or reproduction on the optical disc, servo control by APC or the like does not break down due to a rapid temperature change. As a result, the power value of the laser beam emitted from the light emitting element is stabilized before the process of recording or reproducing on the optical disk is started, thereby improving the quality of recording or reproducing on the optical disk. become.

  As described above, according to the present invention, it is possible to stabilize the temperature related to the LD with a simple mechanism that suppresses the degradation of the performance of the entire device with respect to the temperature change of the light emitting element itself or its surroundings. Recording quality or reproduction quality can be improved.

  According to the present invention, it is possible to provide an optical disc apparatus capable of stabilizing the temperature related to the LD with a simple mechanism while suppressing the degradation of the performance of the entire apparatus, and a control method therefor.

<System configuration>
The optical disk apparatus 100 according to the present invention can employ a multi-pulse system or a non-multi-pulse system as a driving system of a laser diode (hereinafter referred to as LD (Laser Diode)) 11.

  When the multi-pulse method is adopted, the optical disc apparatus 100 emits laser light at a read power value Pr in a space section where a recording mark is not formed, and a read power value Pr and a write power value Pm in a mark section where a recording mark is formed. A laser beam is emitted at a power value corresponding to a recording pulse train having According to the multi-pulse method, a section having the read power value Pr in the mark section can be set as a cooling section, and the heat distribution can be made uniform.

  When the non-multi-pulse method is adopted, the optical disc apparatus 100 forms one recording mark with one recording pulse with a read power value Pr in the space section and a write power value Pm in the mark section. In addition, it is known that the non-multipulse method alone cannot make the heat distribution in the recording mark uniform, and the recording mark is distorted like a tear.

  Therefore, in the case of the non-multi-pulse system, a bias value determined according to the type of the optical disc 200 such as the manufacturer and the recording speed in a predetermined section (hereinafter referred to as an LDH (LD High) section) in the mark section. The LD 11 is driven by superimposing Δ (approximately several to 20% of the difference value between the write power value Pm and the read power value Pr) on the write power value. Note that the ratio between the peak value Ph in the LDH section and the write power value Pm is usually called the Ph / Pm ratio. By adopting such a configuration, the heat distribution in the recording mark can be made uniform.

  The optical disc apparatus 100 according to an embodiment of the present invention shown in FIG. 1 employs a non-multipulse method in which a bias value Δ is superimposed on a write power value in an LDH section. Hereinafter, the configuration of the optical disc apparatus 100 will be described with reference to FIG. 1 while referring to the time chart of FIG. 5 as appropriate.

  The optical pickup 10 includes an LD 11, a front monitor diode 12 (hereinafter referred to as FMD (Front Monitor Diode)), a transmission film 13, a photodetector 14 (hereinafter referred to as PD (Photo Detector)), a temperature sensor 15, Is provided. The optical pickup 10 further includes an optical lens, various actuators for performing thread feeding control, tracking control, focus control, and the like in addition to the above-described configuration. Omitted.

  The LD (“light emitting element”) 11 emits laser light for performing recording and reproduction on the optical disc 200. The LD 11 generates heat when it emits laser light by the current supplied from the LD driver 16. This heat changes the temperature of the LD 11. Furthermore, due to this temperature change, the wavelength of the laser light emitted from the LD 11 varies due to the temperature dependence of the oscillation wavelength in the LD 11.

  The FMD 12 is disposed on the front side of the LD 11 and receives part of the laser light emitted from the LD 11 toward the optical disc 200 via the transmission film 13. The FMD 12 generates a signal corresponding to the current (hereinafter referred to as a power monitor signal) according to the amount of the received laser light.

  The transmission film 13 is disposed on the light receiving side of the FMD 12 and has wavelength dependency so that light having a predetermined wavelength can pass therethrough. For example, in the case of the optical disc apparatus 100 capable of reproducing both CD media and DVD media, the transmissive film 13 is provided with laser light having a wavelength of 780 nm band for CD media, 635 nm band and 650 nm band for DVD media. It is used for the purpose of selecting and transmitting laser light having a wavelength according to the type of media. When the wavelength of the laser beam emitted from the LD 11 varies, the light amount of the laser beam received by the FMD 12 varies due to the wavelength dependence of the transmission film 13.

  The PD 14 receives the reflected light from the optical disc 200 through the transmission film 13, and a current flows according to the received light quantity, and generates a signal corresponding to this current (hereinafter referred to as a reproduction signal). The PD 14 can also be used as the FMD 12. The reproduction signal generated by the PD 14 is supplied to the decoder 19 and subjected to predetermined decoding processing corresponding to the medium of the optical disc 200.

  Further, the reproduction signal generated by the PD 14 is supplied to the servo circuit 37. The servo circuit 37 generates a tracking error signal, a focus error signal, a WBL (Wobble) signal, and the like based on the reproduction signal generated by the PD 14, and performs servo control (tracking control, focus control, thread feeding) of the optical pickup 10. Control) and servo control of the spindle motor 38 that rotationally drives the optical disc 200.

  As the temperature sensor (“temperature detecting means”) 15, a contact sensor such as a thermistor, a thermocouple, or a platinum resistance temperature detector, or a non-contact sensor such as a thermopile can be employed. The temperature sensor 15 is disposed so as to be in contact with or close to the LD 11 on the substrate to which the LD 11 is attached, and detects the temperature of the LD 11 itself or its surroundings. Here, when the temperature of the LD 11 itself is detected, a more accurate temperature can be detected. On the other hand, when the temperature around the LD 11 (for example, in the vicinity of the LD 11) is detected, the temperature sensor 15 can be freely mounted in the optical pickup 10 as compared with the case where the temperature of the LD 11 itself is detected. The optical pickup 10 can be reduced in size.

  The temperature (analog value) detected by the temperature sensor 15 is converted into a digital value by the A / D converter 36 and then input to the system controller 17. Based on the temperature (digital value) information input from the A / D converter 36, the system controller 17 performs a test drive of the LD 11 to be described later in order to stabilize the temperature related to the LD 11.

  The system controller 17 (“control means”) controls the overall system control of the optical disc apparatus 100 related to recording or reproduction of the optical disc 200. For example, the system controller 17 controls the activation of the encoder / decoder 19 in order to perform demodulation or modulation processing according to the optical disc 200 when recording or reproduction is performed on the optical disc 200.

  The system controller 17 supplies a first APC reference voltage signal (digital value) to the D / A converter 21 in order to perform APC (Automatic Power Control) related to the read power value Pr. Similarly, a second APC reference voltage signal (digital value) is supplied to the D / A converter 28 in order to perform APC (Automatic Power Control) related to the write power value Pm.

  The system controller 17 supplies an ACC reference voltage signal (digital value) to the D / A converter 25 in order to perform ACC (Automatic Current Control) related to the write power value Pm for a predetermined period from the start of recording. Since the system controller 17 controls the conduction / non-conduction of the switch 30, as a result, the write power signal VWDC output from the write power signal generation circuit 31 is either the ACC circuit 26 output or the APC circuit 29 output. One is selected.

  Further, the system controller 17 reads the ATT setting value corresponding to the type (manufacturer, recording speed, etc.) of the optical disc 200 from the strategy information stored in the RAM 18, and sets the attenuation rate ATT of the attenuator 33 based on this ATT setting value. To do. The strategy information includes, for example, a recommended Ph / Pm ratio for each manufacturer and recording speed, and an ATT set value corresponding to the Ph / Pm ratio. This strategy information may be stored in advance in the optical disc apparatus 100, or may be recorded in advance in a predetermined area of the optical disc 200, and this information may be sequentially read from the optical disc 200 to update the content of the strategy information. Good.

  The RAM 18 is a memory that can be accessed by the system controller 17. For example, a nonvolatile memory such as an EEPROM or a flash memory, or a volatile memory such as an SRAM or a DRAM can be adopted. The RAM 18 is used when temporarily storing data that is being modulated or demodulated in the encoder / decoder 19.

  The encoder / decoder 19 performs modulation or demodulation processing according to the medium of the optical disc 200. For example, when the optical disc 200 is a CD-R media, EFM (Eight to Fourteen Modulation) is adopted as a modulation method and CIRC (Cross Interleave Reed-Solomon Code) is adopted as an error correction method. Modulation or demodulation processing based on the method is performed.

  The encoder / decoder 19 samples a hold signal RAPC (see FIG. 5D) for holding the previous value after sampling for a predetermined sampling period with respect to the power monitor signal indicating the read power value Pr corresponding to the space section. ) Is supplied to a sample hold (S / H) circuit 20. Similarly, with respect to the power monitor signal indicating the write power value Pm corresponding to the mark section, a sample hold signal WAPC (see FIG. 5G) for holding the previous value after sampling for a predetermined sampling period, A sample hold (S / H) circuit 27 is supplied.

  The encoder / decoder 19 uses an LDON signal (FIG. 5) for setting the conduction / non-conduction of the switch 24 in order to form a recording pulse (see FIG. 5 (a)) on which a bias value Δ is superimposed in the non-multi-pulse method. (See (c)), a PEO signal for setting conduction / non-conduction of the switch 32 (see FIG. 5 (f)), and an LDH signal for setting conduction / non-conduction of the switch 35 (see FIG. 5 (h)). ) For each switch (22, 30, 35). Note that the LDON signal is at a level (H level) at which the switch 24 is turned on in both the space section and the mark section. The PEO signal is set to a level (L level) that makes the switch 32 non-conductive in the space section, and is set to a level (H level) that makes the switch 32 conductive in the mark section. Further, the LDH signal has a level (H level) that makes the switch 35 conductive in a predetermined period (3T to 11T) that is the head of the mark period, and a level (L level) that makes the switch 35 non-conductive in other periods. To do.

  A sample hold (S / H) circuit (20, 27) performs a sample hold process on the power monitor signal detected by the FMD 12 at a timing based on the sample hold signal RAPC / WAPC supplied from the encoder / decoder 19. Execute. Specifically, the sample hold circuit 18 extracts the read power value Pr from the power monitor signal supplied from the FMD 12 during a period (sampling period) when the sample hold signal RAPC is at the H level. On the other hand, the sample hold circuit 25 extracts the write power value Pm from the power monitor signal supplied from the FMD 12 during the period when the sample hold signal WAPC is at the H level (sampling period).

  The APC circuit 22 compares the read power value Pr extracted by the sample and hold circuit 18 with the level of the first APC reference voltage signal converted from the digital value to the analog value by the D / A converter 21. Based on the comparison result, APC is performed so that the read power value Pr is constant (the level of the first APC reference voltage signal).

  Similarly, the APC circuit 29 compares the write power value Pm extracted by the sample and hold circuit 25 with the level of the second APC reference voltage signal converted from the digital value to the analog value by the D / A converter 28. . Based on the comparison result, APC is performed so that the write power value Pm is constant (the level of the second APC reference voltage signal).

  Based on the APC output from the APC circuit 22, the read power signal generation circuit 23 generates a read power signal VRDC (see FIG. 5B) such that the read power value Pr detected by the FMD 12 is constant. The read power signal VRDC is supplied to the LD driver 16 when the switch 24 is turned on by the LDON signal.

  The write power signal generation circuit 31 is supplied with either the ACC output from the ACC circuit 26 or the APC output from the APC circuit 29 by switching the switch 30. Then, the write power signal generation circuit 31 generates a write power signal VRDC (see FIG. 5B) such that the write power value Pm detected by the FMD 12 is constant based on the ACC output or the APC output. The write power signal VRDC is supplied to the LD driver 16 when the switch 32 is turned on by the PEO signal.

  The attenuator 33 is configured by, for example, a combination of a multi-contact switch and a resistor, and the attenuation rate ATT is set based on the ATT set value supplied from the system controller 17. As a result, in the amplifier 34, the gain is set based on the attenuation factor ATT set by the attenuator 33. Then, the amplifier 34 controls the control signal ΔLDH corresponding to the bias value Δ (FIG. 5G) so that the recording pulse output from the LD 11 satisfies the specified Ph / Pm ratio based on the set gain. Reference). The control signal ΔLDH is supplied to the LD driver 16 when the switch 35 is turned on by the LDH signal.

  The LD driver 16 is based on the read power signal VRDC supplied from the read power signal generation circuit 23, the write power signal VWDC supplied from the write power signal generation circuit 31, and the control signal ΔLDH supplied from the amplifier 34. Then, the LD 11 is driven. As a result, in the LDH section, a non-multi-pulse recording pulse on which a predetermined bias value Δ is superimposed is output from the LD 11. Of course, the LD driver 16 is not limited to the non-multi-pulse system, and a multi-pulse system may be adopted. Further, at the time of reproducing the optical disc 200, the LD driver 16 is supplied with only the read power signal VRDC from the read power signal generating circuit 23 and drives the LD 11.

<Operation of optical disc apparatus>
First, on the basis of the flowchart shown in FIG. 2, the operation of the optical disc apparatus 100 (hereinafter referred to as “test preparation process”) required in the previous stage when starting the test drive of the LD 11 will be described. . Next, the operation of the optical disc apparatus 100 related to the test drive of the LD 11 will be described based on the flowchart shown in FIG.

=== Test preparation processing ===
The operation flow of the test preparation process according to the present invention will be described based on the flowchart of FIG. In the following description, the system controller 17 is the main subject of operation unless otherwise specified.

  First, the system controller 17 determines whether or not the optical disk 100 that is stored in a disk storage unit (not shown) is rotating (S200). At this time, based on the information reproduced from the optical disc 100, the optical pickup 10 and the spindle motor 38 are in a standby state so that servo control is activated. If the optical disk 100 is in a rotating state (S200: YES), the thread control of the optical pickup 10 and the servo control for tracking are invalidated (S201).

  Next, the system controller 17 identifies in advance the operation method of the optical disc 100 such as CLV (Constant Linear Velocity) or CAV (Constant Angular Velocity) based on information reproduced from the optical disc 100. Therefore, the system controller 17 determines whether or not the operation method of the optical disc 100 adopts the CLV (Constant Linear Velocity) method (S202). When the CLV method is adopted (S202: YES), the control information necessary for operating in the CLV method cannot be reproduced from the optical disc 200 in response to the invalidity of the thread feeding or tracking servo control. It becomes.

  Therefore, the subsequent rotational speed of the optical disc 200 is calculated based on the information on the speed of the optical disc 200 and the information on the absolute time of the optical disc 100 when the sled feed and tracking servo control is disabled. Based on the calculated rotation speed, the operation is shifted from the CLV operation to the CAV operation (S203).

  Next, the system controller 17 disables the focus servo control including the case where the optical disk 200 is in a rotation stopped state (S200: NO) and the case where the optical disk 200 was originally operating in the CAV method (S202: NO). The laser beam is not focused on the optical disk 200 when the LD 11 is test-driven. Specifically, the position of an optical lens (not shown) included in the optical pickup 10 is adjusted in a direction away from the optical disc 200, and focus servo control is disabled (S204).

  As described above, the system controller 17 performs the test preparation process so that a meaningless recording mark is not formed on the optical disc 200 by the test drive of the LD 11. Thereafter, the test drive of the LD 11 according to the temperature detected by the temperature sensor 15 is performed, and the temperature related to the LD 11 is stabilized (S205). The details of the test drive of the LD 11 will be described later.

  After the test drive of the LD 11 is completed, the temperature related to the LD 11 is stabilized, the wavelength fluctuation of the output of the LD 11 is suppressed, and the fluctuation of the light amount of the laser beam received by the FMD 12 is suppressed. The process of recording or reproducing to 200 can be started. Before performing recording or reproduction processing on the optical disc 200, the position of an optical lens (not shown) provided in the optical pickup 10 is returned to a normal position, and thread feeding, tracking, and focus servo control of the optical pickup 10 are performed. Of course, it is effective (S206).

=== Test drive of LD ===
Based on the flowchart of FIG. 3, the operation flow of the test drive of the LD 11 according to the present invention will be described. In the following description, the system controller 17 is the main subject of operation unless otherwise specified.

  First, when test drive of the LD 11 is started, time measurement is started in a system timer (not shown) provided in the system controller 17 or the like. Here, the system controller 17 stores a parameter t for storing information of the measured time in the RAM 18 or the like. The contents of the parameter t are sequentially updated as time passes (S300).

  When the time measurement is started (t = 0), the system controller 17 obtains the temperature y detected by the temperature sensor 11 by calculation using the output x of the A / D converter 36. For example, “y = 0.00007 × (x squared) −0.1873 x + 100.4” is used as an arithmetic expression Z for performing this calculation. Here, the temperature y obtained by the arithmetic expression Z is held in the parameter y_save (S301).

  When the test drive of the LD 11 is started, the system controller 17 sets the read power signal generation circuit 23 and the write power so that the output of the LD 11 is set to a test power value larger than the read power value Pr and the write power value Pm. The power signal generation circuit 31 and the like are controlled (S302). The test power value is, for example, about 80% of the maximum rating of the output of the LD 11.

  As described above, the LD 11 is warmed up while the test drive of the LD 11 is being executed before actually recording or reproducing the optical disk 200. In particular, by setting the test power value larger than the read power value Pr and the write power value Pm from the time when the test drive of the LD 11 is started, the temperature change related to the LD 11 is accelerated at a stroke, and recording or recording on the optical disc 200 is performed. Immediately approach the state where the playback process is performed. As a result, the test drive of the LD 11 can be completed in a short time, and the process of recording or reproducing on the optical disc 200 can be started quickly.

  The warming up of the output of the LD 11 is continued until “10” seconds elapse from the start of the test drive of the LD 11 (S303: NO). Thereafter, when “10 seconds” have elapsed (S303: YES), it is determined whether or not the content of the parameter t is within “60 seconds” (S304). Note that “60 seconds” is the maximum required time related to the test drive of the LD 11 which is set to avoid the situation where the test drive of the LD 11 falls into an infinite loop and does not end at once. Therefore, when this maximum required time has elapsed (S304: NO), the test drive of the LD 11 is forcibly terminated as a timeout. Of course, the maximum required time is not limited to “60 seconds”.

  When “10 seconds” has elapsed since the start of the test drive of the LD 11 (S303: YES) and “60 seconds” has not elapsed (S304: YES), the system controller 17 outputs the output x of the A / D converter 36. The temperature y detected by the temperature sensor 11 is obtained by the above-described arithmetic expression Z (S305). The difference between the obtained temperature y and the parameter y_save that holds the temperature y obtained when t = 0 or 10 seconds ago is within a predetermined range indicating that the temperature related to the LD 11 has stabilized ( For example, it is determined whether the temperature is within 2 ° C. or less (S306).

  When the difference between the temperature y and the parameter y_save does not fall within the predetermined range (S306: NO), the content of the parameter y_save is updated to the temperature y (S307), and the processing after S302 is subsequently performed. That is, every time “10 seconds” elapse until the difference between the temperature y and the parameter y_save falls within a predetermined range (only within “60 seconds”), the system controller 17 limits the A / D converter 36. The output x is read to calculate the temperature y, and the power value of the output of the LD 11 is adjusted according to the calculated temperature y.

  When the difference between the temperature y and the parameter y_save falls within the predetermined range (S306: YES) or when “60 seconds” has elapsed (S304: NO), the system controller 17 keeps the temperature related to the LD 11 in a stable state. The test drive of the LD 11 is terminated. Then, recording or reproduction processing on the optical disc 200 is started (S308).

  FIG. 4 is a diagram illustrating how the temperature related to the LD 11 is stabilized by executing the test drive of the LD 11. In the figure, when "40 seconds" have elapsed since the start of the test drive of the LD 11, the temperature y (40) at "40 seconds" and the temperature y (30) at "30 seconds" In this example, the difference between the two is within 2 ° C. and the test drive of the LD 11 is completed. In other words, in the example shown in the figure, the system controller 17 reads the temperature y detected by the temperature sensor 15 a total of five times. Further, the system controller 17 adjusts the power value of the output of the LD 11 according to the temperature y three times in total.

  As described above, the optical disc apparatus 100 has been focusing on the fact that the temperature related to the LD 11 is rapidly changed by the heat generated from the LD 11 at the initial stage when the LD 11 is driven. Before actually starting the operation, the LD 11 is test-driven to stabilize the temperature of the LD 11. Note that the test drive of the LD 11 is always terminated before the process of recording or reproducing on the optical disc 200 is started. In addition, the system controller 17 acquires the temperature y detected by the temperature sensor 15 at a predetermined time (for example, “10 seconds”) instead of acquiring the temperature y detected by the temperature sensor 15 in the test drive of the LD 11. The adjustment of the power value of the output of the LD 11 based on is performed not at real time but every predetermined time.

  The optical disc apparatus 100 can stabilize the temperature related to the LD 11 while performing a test drive of the LD 11 as described above, while suppressing a decrease in performance of the entire apparatus such as the system controller 17. Further, when the read power value Pr and the write power value Pm are set, servo control by APC or the like does not fail due to a rapid temperature change. As a result, the power value of the laser beam emitted from the LD 11 is stabilized during the recording or reproducing process on the optical disc 200, and the recording or reproducing quality on the optical disc 200 is improved.

  That is, according to the present invention, the temperature related to the LD 11 can be stabilized by a simple mechanism that suppresses the performance degradation of the system controller 17 and the like, and as a result, the recording or reproduction quality on the optical disc 200 can be improved. .

  As mentioned above, although embodiment of this invention was described concretely, it is not limited to this, A various change is possible in the range which does not deviate from the summary.

1 is a system configuration diagram of an optical disc apparatus according to an embodiment of the present invention. 6 is a flowchart for explaining the operation of the optical disc apparatus according to the embodiment of the present invention. 6 is a flowchart for explaining the operation of the optical disc apparatus according to the embodiment of the present invention. It is a figure which shows a mode that the temperature which concerns on a laser diode is stabilized by operation | movement of the optical disk apparatus which concerns on embodiment of this invention. It is a wave form diagram explaining operation | movement of the optical disk apparatus based on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical pick-up 11 Laser diode 12 Front monitor diode 13 Transmission film 14 Photo detector 15 Temperature sensor 16 LD driver 17 System controller 18 RAM 19 Encoder / decoder 20 Sample hold circuit 21 D / A converter 22 APC circuit 23 Read power signal generation circuit 24 switch 25 D / A converter 26 ACC circuit 27 sample hold circuit 28 D / A converter 29 APC circuit 30 switch 31 write power signal generation circuit 32 switch 33 attenuator 34 amplifier 35 switch 100 optical disk device 200 optical disk

Claims (7)

An optical disc apparatus that sets a power value of laser light emitted from a light emitting element to an optical disc, drives the light emitting device, and performs recording and / or reproduction processing on the optical disc,
Means for detecting the temperature of the light emitting element;
Start the test drive of the light emitting element before starting the recording or reproduction processing to the optical disc,
The temperature detected by the means is acquired every time a predetermined time has elapsed since the start of the test drive,
When the difference between the acquired temperature and the temperature acquired a predetermined time before the temperature is acquired is within a predetermined range, the test drive is terminated.
Control means for starting recording or reproduction processing on the optical disc;
An optical disc apparatus comprising:   The optical disk apparatus according to claim 1, wherein the temperature detecting unit detects a temperature of the light emitting element itself.   The optical disk apparatus according to claim 1, wherein the temperature detecting unit detects a temperature around the light emitting element. The control means includes
Driving the light emitting element with the laser light having a test power value larger than a power value for performing recording or reproduction on the optical disc while performing the test drive;
The optical disc apparatus according to claim 1. The control means includes
Driving the light emitting element with the laser light having the test power value from the time when the test driving is started;
The optical disc apparatus according to claim 4. The control means includes
When the predetermined maximum time has elapsed since the start of the test drive, the test drive is terminated.
The optical disc apparatus according to claim 1, wherein: A method of controlling an optical disc apparatus that sets a power value of laser light emitted from a light emitting element to an optical disc, drives the light emitting device, and performs recording and / or reproduction processing on the optical disc,
Detecting the temperature of the light emitting element;
Start the test drive of the light emitting element before starting the recording or reproduction processing to the optical disc,
The temperature detected by the means is acquired every time a predetermined time has elapsed since the start of the test drive,
When the difference between the acquired temperature and the temperature acquired a predetermined time before the temperature is acquired is within a predetermined range, the test drive is terminated.
Start recording or playback processing on the optical disc;
A method of controlling an optical disk device, comprising:

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