JP4072739B2 - Method for adjusting reproduction accuracy by reproduction apparatus and reproduction apparatus - Google Patents

Description

[0001]
【table of contents】
The present invention will be described in the following order.
[0002]
TECHNICAL FIELD OF THE INVENTION
Conventional technology
Problems to be solved by the invention
Means for solving the problems (FIGS. 1 to 7)
BEST MODE FOR CARRYING OUT THE INVENTION
(1) Configuration of the disk recording / reproducing apparatus according to the present embodiment (FIGS. 1 to 6)
(2) RF (Radio Frequency) signal amplitude adjustment processing (FIG. 7)
(3) Operation and effect of the present embodiment (FIGS. 1 to 7)
(4) Other embodiments (FIGS. 1 to 7)
The invention's effect
[0003]
BACKGROUND OF THE INVENTION
  The present inventionPlayback accuracy by playback deviceAdjustment method andRegenerationThe apparatus is suitable for application to a disk recording / reproducing apparatus for recording / reproducing data on, for example, a 5.25 inch magneto-optical disk.
[0004]
[Prior art]
Conventionally, a 5.25 inch magneto-optical disk has a plurality of types of standards such as a data recording density of 1-fold density, 2-fold density, 3-fold density, 4-fold density, and 8-fold density. There are several types of recording formats such as MO (Magneto Optical), CCW (Continuos Composite Write once), WORM (Write Once Read Many), and Lim-DOW (Light intensity modulation-Direct Over Write). Yes. Further, the recording format of data in units of sectors is standardized as 2K, 1K, and 512, and there are 30 or more media types in total.
[0005]
In this case, in these various media type magneto-optical disks, the track pitch, the spiral direction of the track, the reflectance of the laser light irradiation surface during recording / reproduction (hereinafter simply referred to as the irradiation surface), and the laser light during recording / reproduction. Because of the difference in the light intensity, etc., the area called PEP (Phase-Encoded Part of the control tracks) in which the format information of this magneto-optical disk is recorded in the innermost peripheral area (from the center hole regardless of the media type) (Recorded in a format called PE (Phase-Encoded)) with the same distance and width.
[0006]
Thus, in a disk recording / reproducing apparatus for recording / reproducing data on this type of magneto-optical disk, it is determined which media type the magneto-optical disk is based on format information recorded on the PEP of the magneto-optical disk. Data is recorded and reproduced according to the determination result.
[0007]
[Problems to be solved by the invention]
By the way, in such a disk recording / reproducing apparatus, at the time of data reproduction, an analog RF signal obtained by reproducing from a magneto-optical disk is sequentially output via an operational amplifier and an analog digital converter. Since the reflectivity of the irradiated surface of the magneto-optical disk differs from the light intensity of the laser light irradiated to the irradiated surface during data reproduction, the amplitude of the RF signal varies depending on the media type, and remains as it is. Then, it becomes difficult to correctly convert the RF signal into analog digital.
[0008]
For this reason, in this disk recording / reproducing apparatus, the RF signal amplitude is set to a preset threshold value (hereinafter referred to as the following) by actually adjusting the gain of the operational amplifier in the shipping inspection of the manufacturing factory that manufactures the disk recording / reproducing apparatus. This is adjusted so as to be smaller than the first amplitude threshold value, and the electric offset amount of the operational amplifier is set to a preset threshold value (hereinafter referred to as the first threshold value). (This is called the offset threshold value.) Since this is adjusted so that it is smaller than the offset threshold value, the operational amplifier is adjusted by this shipment inspection every time the magneto-optical disk is set when reproducing data in the market. The gain and offset amount of the operational amplifier are adjusted by using the first amplitude threshold value and the first offset threshold value used in the processing. Ri amplitude of the RF signal are adjusted to properly be analog-to-digital conversion.
[0009]
In this case, in the shipping inspection, a magneto-optical disk manufactured with relatively high accuracy is used, and the gain and offset amount of the operational amplifier are adjusted in an environment in which fluctuations in temperature, dust, and power supply voltage are strictly controlled. Based on the variation in the adjustment result, the LSI (Large Scale Integration) element in which the operational amplifier and the analog digital converter are integrally formed is inspected for quality as specified, so the first amplitude is used. The threshold value and the first offset threshold are set to relatively small values.
[0010]
On the other hand, in the market, even if the media type is the same, if the manufacturer is different, the reflectance on the irradiated surface of the magneto-optical disk will vary, and data will be reproduced in an unstable environment due to temperature and dust. Therefore, the adjustment processing of the operational amplifier using the first amplitude threshold value and the first offset threshold value is too precise, and it is difficult to adjust the amplitude of the RF signal so that it can be correctly analog-digital converted. In such a case, there is a problem that a reproduction error occurs in the magneto-optical disk.
[0011]
As a method for solving such a problem, in the operational amplifier adjustment processing by shipping inspection, a threshold value that is larger than the first amplitude threshold value and the first offset threshold value is used. It is considered that the threshold value is also used for adjustment processing of an operational amplifier in the market.
[0012]
However, in this method, when a threshold value larger than the first amplitude threshold value and the first offset threshold value is used in the shipping inspection, the inspection standard of the LSI element is loosened accordingly. As a result, disk recording / reproducing devices equipped with the most limited LSI elements are shipped to the market, and this LSI element malfunctions when the environment such as temperature is poor in the market. This causes a playback error.
[0013]
  The present invention has been made in consideration of the above points, and can greatly reduce the occurrence of reproduction errors on a disc-shaped recording medium.Playback accuracy by playback deviceAdjustment method andRegenerationThe device is to be proposed.
[0014]
[Means for Solving the Problems]
  In order to solve this problem, in the present invention,In the reproduction accuracy adjustment method for adjusting the reproduction accuracy of the disc-shaped recording medium by the reproduction device by the adjusting means provided in the reproduction device,  Adjusting means of the playback deviceDisc-shaped recording mediumthe body'sA first step of adjusting the reproduction accuracy at the time of shipping inspection so as to be within a predetermined first range;Adjustment meansA second step of adjusting the reproduction accuracy after the shipping inspection so as to be within a predetermined second range in which the first range is relaxed, and in the first step,Adjustment meansThe amplitude of a reproduction signal obtained by reproducing from a disk-shaped recording medium representing the reproduction accuracy,The playback device remembersThe gain and offset amount of the operational amplifier so as to be within a first range that is less than or equal to a predetermined first threshold value.At least one ofAnd in the second step,Adjusting means of the playback deviceThe amplitude of the reproduction signal is larger than the first threshold valueThe playback device remembersThe gain and offset amount of the operational amplifier so as to be within the second range below the predetermined second threshold value.At least one ofAnd the second threshold value is increased by about 10 to 30% in accordance with the variation in the reflectance on the laser light irradiation surface of the disk-shaped recording medium. It was made to become a value.
[0015]
As a result, it is possible to adjust the reproduction accuracy even when there is a variation in the reflectance on the laser light irradiation surface of the disk-shaped recording medium after the shipment inspection without lowering the inspection standard at the time of the shipment inspection of the reproduction apparatus.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[0017]
(1) Configuration of the disk recording / reproducing apparatus according to the present embodiment
In FIG. 1, reference numeral 1 denotes a disk recording / reproducing apparatus according to the present invention as a whole. A controller 2 sends a recording control signal S1 to a DSP (Digital Signal Processor) 3 in a recording mode, thereby causing the DSP 3 to The spindle motor 5 is driven and controlled via the driver 4, and the magneto-optical disk 7 set on the turntable 6 is rotated at a predetermined rotational speed.
[0018]
Further, the controller 2 performs predetermined signal processing such as conversion (1-7 conversion or 2-7 conversion) by a method corresponding to the media type of the magneto-optical disk 7 with respect to the recording data D1 given from the outside, This is sent to the laser power controller (LPC) 8 as write data D2.
[0019]
The laser power controller 8 is driven based on the drive control signal S4 supplied from the DSP 3, generates a control signal S5 based on the write data D2 supplied from the controller 2, and sends the control signal S5 to the optical block 9 to transmit the optical signal. The laser light L1 emitted from a laser light source (not shown) in the block 9 is blinked according to the light data D2.
[0020]
In this case, the magnetic field application unit 10 is disposed on the extended line of the laser beam L1, and the DSP 3 controls the drive of the magnetic field application unit 10 via the magnet driver 11 to irradiate the laser beam L1 on the magneto-optical disk 7. A magnetic field in a predetermined direction is applied to the position and magnetized.
[0021]
Thus, the disk recording / reproducing apparatus 1 can record the write data D2 on the magneto-optical disk 7 based on the laser light L1 emitted from the laser light source of the optical block 9.
[0022]
At this time, the optical block 9 receives the reflected light L2 of the laser light L1 on the magneto-optical disk 7 with a photodetector (not shown), and based on the received light output of the photodetector, the focus error signal S8 and tracking error. The signal S9 is generated and sent to the DSP 3.
[0023]
The optical block 9 detects a deviation of the objective lens (not shown) from the center position in the track direction by a midpoint sensor (not shown), and sends this to the DSP 3 as a slide error signal S10.
[0024]
The DSP 3 sends a focus control signal S11 based on the focus error signal S8 to the focus driver 12, and the focus driver 12 sends a drive signal S12 based on the focus control signal S11 to the focus block disposed in the optical block 9. This is driven as necessary by sending it to an actuator (not shown).
[0025]
The DSP 3 sends a tracking control signal S13 based on the tracking error signal S9 to the tracking driver 13, and the tracking driver 13 is provided with a drive signal S14 based on the tracking control signal S13 in the optical block 9. This is driven as required by sending it to a tracking actuator (not shown).
[0026]
Further, the DSP 3 sends a slide control signal S15 based on the slide error signal S10 to the slide driver 14, and the slide driver 14 sends a drive signal S16 based on the slide control signal S15 to the slider 15 disposed in the optical block 9. By sending it, the optical block 9 is moved in the radial direction as necessary.
[0027]
In this way, the disk recording / reproducing apparatus 1 performs the focus control, tracking control and slide control based on the focus error signal S8, tracking error signal S9 and slide error signal S10 output from the optical block 9. Has been made.
[0028]
On the other hand, in the playback mode, the controller 2 sends a playback control signal S17 to the DSP 3, whereby the DSP 3 rotates the magneto-optical disk 7 set on the turntable 6 at a predetermined rotational speed in the same manner as in the recording mode described above. At the same time, the laser light source in the optical block 9 is driven via the laser power controller 8 to irradiate the magneto-optical disk 7 with the laser light L1 having a predetermined light intensity.
[0029]
The reflected light L2 of the laser light L1 on the magneto-optical disk 7 is photoelectrically converted by the photodetector in the optical block 9, and the RF signal S18 thus obtained is digitally converted in the lead channel 16 having the LSI element structure. Then, a predetermined reproduction process is performed in the controller 2, and thereafter, the reproduction data D3 is output to the outside.
[0030]
  At this time, the DSP 3 receives the focus error signal S8, tracking error signal S9, and slide error signal S10 from the optical block 9 in the same manner as in the recording mode described above.IsAccordingly, the focus control, tracking control and slide control are performed in the same manner as described above based on the focus error signal S8, tracking error signal S9 and slide error signal S10.
[0031]
Incidentally, when the magneto-optical disk 7 is set on the turntable 6 in the recording mode and the reproduction mode, the controller 2 rotates the magneto-optical disk 7 in the same manner as described above, and then the recording control signal S1 and the reproduction control signal. By sending a seek command signal S20 to the DSP 3 prior to S17, the DSP 3 drives and controls the slider 15 in the optical block 9 via the slide driver 14, and thus the optical block 9 is moved in the inner circumferential direction of the magneto-optical disk 7. Move to.
[0032]
In this case, a linear scale (not shown) is fixedly arranged on the movable body (not shown) of the slider 15 of the optical block 9, and in the vicinity of the PEP provided in the innermost peripheral area of the magneto-optical disk 7. A linear encoder 17 composed of a reflective encoder is fixedly arranged at a predetermined position, and the linear encoder 17 detects the moving distance and moving direction of the optical block 9 based on the position of the linear scale with respect to the linear encoder 17. The detection result is sent to the DSP 3 as a movement detection signal S21.
[0033]
The DSP 3 drives and controls the slider 15 via the slide driver 14 in accordance with the moving distance and moving direction of the optical block 9 obtained based on the movement detection signal S21, so that the optical block 9 is temporarily moved to the outermost position of the magneto-optical disk 7. It is moved to a predetermined position facing the mirror area (mirror-like area) located in the inner peripheral area.
[0034]
The DSP 3 drives and controls the laser light source in the optical block 9 via the laser power controller 8 and controls the actuator for the focus in the optical block 9 via the focus driver 12 from the laser light source. The laser beam L1 having a predetermined light intensity is irradiated onto the magneto-optical disk 7 while controlling the focus.
[0035]
In this state, the DSP 3 controls the drive of the slider 15 via the slide driver 14 based on the movement detection signal S21 to move the optical block 9 to a position facing the PEP (not shown) of the magneto-optical disk 7. Then, this PEP is irradiated with the laser beam L1 for a predetermined time.
[0036]
In this way, the reflected light L2 of the laser beam L1 on the PEP of the magneto-optical disk 7 is photoelectrically converted by the photodetector in the optical block 9, and the obtained RF signal S18 is digitally converted by the read channel 16 and then converted into a format. It is sent to the DSP 3 as mat data D4.
[0037]
Thus, the DSP 3 decodes the format data D4 given from the read channel 16 and discriminates the media type of the magneto-optical disk 7 based on the format information obtained as a result. The light intensity of the laser light L1 emitted from the laser light source, the conversion method of the recording data D1 by the controller 2, and the like are switched as necessary.
[0038]
By the way, this disk recording / reproducing apparatus 1 uses, for example, an 8-times dense magneto-optical disk manufactured with relatively high accuracy by shipping inspection at a manufacturing plant, and strictly manages fluctuations in temperature, dust, power supply voltage, and the like. Under the specified environment, the lead channel 16 is exchanged as necessary, and the amplitude of the RF signal is determined based on the first amplitude threshold and the first offset threshold. The gain and offset amount of the operational amplifier in the lead channel 16 are adjusted using the first amplitude threshold value and the first offset threshold value so as to be within the range.
[0039]
In the disk recording / reproducing apparatus 1, a gain adjustment value and an offset amount adjustment value corresponding to an 8 × density media type obtained by the adjustment processing of the operational amplifier are provided in the DSP 3. (Not shown) and 1 × dense, 2 × respectively obtained from a gain adjustment value corresponding to the 8 × dense media type and an offset amount adjustment value based on a predetermined conversion formula The gain adjustment value and the offset amount adjustment value corresponding to the dense, triple density, and quadruple density media types are stored in the DSP 3 internal memory.
[0040]
Further, in the memory inside the DSP 3, the first amplitude threshold value is increased by about 10 to 30% in accordance with the variation (by the manufacturer) in the reflectance on the irradiation surface of the magneto-optical disk 7. In a market set so that the second threshold value for amplitude adjustment in the set market and the first offset threshold value are similarly increased by about 10 to 30%. The second offset threshold value for adjusting the offset amount is stored.
[0041]
In this case, as shown in FIG. 2, when the DSP 3 discriminates the media type of the magneto-optical disc 7 in the reproduction mode, the gain adjustment value and the offset amount corresponding to the discrimination result are stored from an internal memory (not shown). The gain control signal S25 based on the gain adjustment value and the offset amount control signal S26 based on the offset amount adjustment value are supplied to the inner register 21 via the serial bus 20.
[0042]
The inner register 21 sets the gain of the operational amplifier 22 to the same value as the gain set by the adjustment process of the operational amplifier in the shipping inspection based on the gain control signal S25 given from the DSP 3, and also sets the gain to the offset amount control signal S26. Based on this, the offset amount of the operational amplifier 22 is set to the same value as the offset amount set by the adjustment processing of the operational amplifier in the shipping inspection.
[0043]
As a result, the operational amplifier 22 amplifies the RF signal S18 given from the optical block 9, and then sends it to the controller 2 via the analog digital converter (A / D converter) 23, and the amplitude of the amplified RF signal S18. Is detected at a predetermined timing and used as an amplitude signal S27, and a voltage value corresponding to the offset amount is detected at a similar timing and used as an offset signal S28. Give and remember.
[0044]
In this case, the DSP 3 sequentially reads the amplitude signal S27 and the offset signal S28 stored in the inner register 22 through the serial bus 20, and uses the second amplitude threshold value and the second offset value from the memory. The threshold value is read out, and an amplitude control signal S25 based on the amplitude signal S27 and the second amplitude threshold value is applied to the inner register 21, thereby adjusting the gain of the operational amplifier 22 and the offset signal S28 and the second signal. The offset amount of the operational amplifier 22 is adjusted by providing the inner register 21 with an offset control signal S26 based on the offset threshold.
[0045]
In this way, the DSP 3 adjusts the gain and offset amount of the operational amplifier 22 so as to be equal to or less than the corresponding second amplitude threshold value and second offset threshold value, and thus the magneto-optical disk 7. The amplitude of the RF signal S18 obtained by reproducing from the above is adjusted to be within a second range wider than the first range based on the second amplitude threshold and the second offset threshold. It is made to do.
[0046]
In this embodiment, the DSP 3 rotates the spindle motor 5 by sending a signal having a predetermined polarity to the spindle driver 4. At this time, every time the spindle motor 5 makes one rotation from the spindle driver 4, the DSP 3 rotates 4 times. When a rotational speed detection signal composed of various types of rectangular waves is given, the time widths of the four types of rectangular waves obtained based on the rotational speed detection signals are detected, and the rotational speed of the spindle motor 5 is determined based on the detection results. Monitor. The DSP 3 sends the rotational speed lock signal to the spindle driver 4 when the rotational speed of the spindle motor 5 reaches a predetermined rotational speed preset for data recording and / or reproduction, thereby adjusting the rotational speed of the spindle motor 5. When the time width of the four types of rectangular waves becomes larger than a preset threshold value, the spindle motor 5 is sent by sending a signal whose polarity is reversed from that at the start of rotation to the spindle driver 4. Stop rotating.
[0047]
In the case of this embodiment, when the photodetector in the optical block 9 receives the reflected light L2 in the recording mode and the reproducing mode, it gives a pull-in signal corresponding to the light quantity to the DSP 3, so that the DSP 3 is based on this pull-in signal. Then, it is detected whether or not the entire photodetector receives the reflected light L2 having a sufficient amount of light.
[0048]
  Furthermore, in the case of this embodiment,3As shown in FIG. 4, in order to actually erase data in the recording mode, the side of the magnetic field applying unit 10 facing the upper surface of the magneto-optical disk 7 is set to, for example, the N pole, In this state, the laser beam L1 is sequentially emitted, for example, by sequentially irradiating the magnetic film 7B at the data erasure target position 7A while rotating the magneto-optical disk 7 in a predetermined direction B. An N-pole magnetic field is magnetized on the magnetic film 7B at each data erasure target position 7A, and thus data can be erased.
[0049]
  In contrast to this4As shown in FIG. 4, in order to actually record data in the recording mode, the side of the magnetic field applying unit 10 facing the upper surface of the magneto-optical disk 7 is set to, for example, the S pole, and the optical block 9 is used for data recording. The laser beam L1 having a light intensity of 1 is emitted so as to blink, and in this state, the magneto-optical disk 7 is rotated in a predetermined direction B and a magnetic field having a polarity (S pole) different from that at the time of erasure is to be magnetized By irradiating the magnetic film 7B in the region 7C with the laser beam L1, the magnetic film 7B in the recording target region 7C is magnetized, and thus data can be recorded.
[0050]
  Furthermore, in the case of this embodiment,5~ Figure6As shown in (B), in the reproduction mode, data is actually reproduced using the Kerr effect, and when the magnetic film 7B of the magneto-optical disk 7 is irradiated with the laser light L1 (linear deflection), From the magnetic film 7B, the reflected light L2 whose deflection direction rotates to + θk or −θk according to the magnetic field (N pole or S pole) magnetized thereto can be obtained (see FIG.5), The reflected light L2 (FIG.6(A)) is caused to pass through the analyzer 30 to cause the intensity of the light intensity corresponding to the rotation in the deflection direction (see FIG.6(B)) The photodetector can receive light, and thus data can be reproduced according to the intensity of the light reception result.
[0051]
(2) RF signal amplitude adjustment processing
Here, in practice, in the disk recording / reproducing apparatus 1, the amplitude of the RF signal S18 can be adjusted by the following procedure shown in FIG.
[0052]
That is, when the DSP 3 discriminates the media type of the magneto-optical disk 7 in the reproduction mode, the RF signal adjustment processing procedure RT1 shown in FIG. 7 is started at step SP1, and then the media type discrimination result from the memory at the subsequent step SP2. The gain adjustment value and the offset amount adjustment value corresponding to the values are read out, and the read gain adjustment value and offset amount adjustment value are respectively stored in the inner register 21 as a gain control signal S25 and an offset amount control signal S26. Thus, the gain of the operational amplifier 22 is set according to the gain control signal S25, and the offset amount of the operational amplifier 22 is set according to the offset amount control signal S26.
[0053]
Next, the DSP 3 proceeds to step SP3, reads the amplitude signal S27 from the inner register 21, and detects the amplitude of the RF signal S18 based on the amplitude signal S27.
[0054]
Subsequently, the DSP 3 proceeds to step SP4 to read out the second amplitude threshold value TH1 from the memory, and at the same time, detects the second amplitude threshold value TH1, the reference value of the preset amplitude and the actual detection. The absolute value of the difference in amplitude of the RF signal S18 is compared, and it is determined whether or not the absolute value of this difference is equal to or less than the second amplitude threshold value TH1.
[0055]
In this case, obtaining an affirmative result at step SP4 indicates that the amplitude of the RF signal S18 is adjusted to an optimum value. At this time, the DSP 3 proceeds to the following step SP5, from the inner register 21. The offset signal S28 is read out, and the offset amount of the operational amplifier 22 is detected based on the offset signal S28.
[0056]
Next, the DSP 3 proceeds to step SP6 to read out the second offset threshold value TH2 from the memory, and at the same time, detects the second offset threshold value TH2, the preset reference value of the offset amount and the actual detection. The absolute value of the difference in the offset amount of the operational amplifier 22 is compared, and it is determined whether or not the absolute value of the difference is equal to or less than the second offset threshold TH2.
[0057]
In this case, obtaining a positive result in step SP6 means that the offset amount of the operational amplifier 22 has been adjusted to an optimum value for amplifying the RF signal S18. At this time, the DSP 3 proceeds to the following step SP7. This RF signal adjustment processing procedure RT1 is terminated.
[0058]
On the other hand, obtaining a negative result in step SP6 indicates that the offset amount of the operational amplifier 22 has not been adjusted to the optimum value for amplifying the RF signal S18. At this time, the DSP 3 sets the step SP8. Then, an offset amount control signal S26 is generated based on the determination result of step SP6, and is supplied to the inner register 21, thereby adjusting the offset amount of the operational amplifier 22, and then returns to step SP5.
[0059]
Then, the DSP 3 sequentially repeats the loop of steps SP6-SP8-SP5-SP6 until the offset amount of the operational amplifier 22 reaches an optimum value for amplifying the RF signal S18. However, the DSP 3 is set in the turntable 6 at this time if the offset amount of the operational amplifier 22 cannot be adjusted even if the loop of the steps SP6-SP8-SP5-SP6 is repeated up to 20 times, for example. It is determined that the magneto-optical disk 7 is the magneto-optical disk 7 in which it is difficult to reproduce data, and the process proceeds to step SP7 to end the RF signal adjustment processing procedure RT1, and an error occurs in the magneto-optical disk 7. For example, the user is notified via a monitor or a speaker.
[0060]
In addition, obtaining a negative result in step SP4 described above means that the amplitude of the RF signal S18 has not been adjusted to the optimum magnitude, and at this time DSP3 proceeds to step SP9 and obtained in step SP3. Based on the determination result, a gain control signal S25 is generated and given to the inner register 21, thereby controlling the gain of the operational amplifier 22.
[0061]
After that, the DSP 3 proceeds to step SP10, reads the offset signal S28 from the inner register 21 again, and detects the offset amount of the operational amplifier 22 based on the offset signal S28.
[0062]
Next, the DSP 3 proceeds to step SP11, obtains the absolute value of the difference between the reference value of the offset amount and the offset amount detected in step SP10, and calculates the absolute value of this difference and the second offset threshold TH2. To determine whether the absolute value of the difference is equal to or smaller than the second offset threshold TH2.
[0063]
If the DSP 3 obtains a positive result at step SP11, it returns to step SP3. On the other hand, if it obtains a negative result at step SP11, it proceeds to step SP12. The amount of offset is adjusted, and then the loop of steps SP11-SP12-SP10-SP11 is repeated so as to return to step SP10.
[0064]
However, the DSP 3 adjusts the offset amount of the operational amplifier 22 even if the loop of the steps SP11-SP12-SP10-SP11 is repeated up to, for example, 20 times similarly to the loop of the steps SP6-SP8-SP5-SP6 described above. If not, it is determined that the magneto-optical disk 7 set on the turntable 6 at this time is an error-prone magneto-optical disk 7 where it is difficult to reproduce data, and the process proceeds to step SP7 (not shown). At the same time as the RF signal adjustment processing procedure RT1 is completed, the fact that an error has occurred in the magneto-optical disk 7 is notified to the user via, for example, a monitor or a speaker.
[0065]
  The DSP 3 proceeds to step SP9 because a negative result is obtained at step SP4, and thereafter repeats the loop of steps SP4-SP9-SP10-SP11-SP3-SP4.TheIf the amplitude of the RF signal S18 cannot be adjusted to the optimum size for analog-digital conversion even if this loop is repeated 20 times at the maximum, for example, the turntable 6 It is determined that the set magneto-optical disk 7 is an magneto-optical disk 7 in which an error is difficult to reproduce data, and the process proceeds to step SP7 (not shown) to complete this RF signal adjustment processing procedure RT1. The user is notified of an error in the magneto-optical disk 7 via, for example, a monitor or a speaker.
[0066]
Incidentally, in this disk recording / reproducing apparatus 1, during the adjustment process of the operational amplifier 22 in the shipping inspection, the gain of the operational amplifier 22 is preset according to the standard instead of the step SP2 of the RF signal adjustment processing procedure RT1 shown in FIG. And the offset amount of the operational amplifier 22 is set to the initial value of the offset amount set in advance according to the standard, and the second amplitude threshold value and the second offset value are set. The amplitude of the RF signal S18 is processed in the same manner as the RF signal adjustment processing procedure RT1 except that the first amplitude threshold value and the first offset threshold value are used instead of the threshold value. Adjust.
[0067]
(3) Operation and effect of the present embodiment
In the disk recording / reproducing apparatus 1 having the above configuration, the temperature, dust and power supply voltage fluctuations are severe by using a magneto-optical disk manufactured with relatively high accuracy during the adjustment process of the operational amplifier 22 in the shipping inspection. Under the controlled environment, the gain and offset amount of the operational amplifier are actually adjusted using the first amplitude threshold value and the first offset threshold value.
[0068]
Then, the gain adjustment value and the offset amount adjustment value for each media type obtained at this time, and the first amplitude threshold value and the first offset threshold value in accordance with the adjustment processing of the operational amplifier 22 in the market. The second amplitude threshold value and the second offset threshold value generated so as to be increased by about 10 to 30% are stored in the DSP 3 internal memory.
[0069]
In this state, when the disk recording / reproducing apparatus 1 is actually shipped to the market and the magneto-optical disk 7 is set on the turntable 5 to reproduce data from the magneto-optical disk 7, the adjustment of the operational amplifier 22 in this market is performed. The processing is started, and the gain and the offset value of the operational amplifier 22 are adjusted using the second amplitude threshold and the second offset threshold.
[0070]
Therefore, the disk recording / reproducing apparatus 1 uses the first amplitude threshold value and the first offset threshold value which are relatively small during the adjustment process of the operational amplifier 22 in the shipping inspection as described above. Since the second amplitude threshold value and the second offset threshold value which are larger than the first amplitude threshold value and the first offset threshold value are used during the adjustment process of the operational amplifier 22, Without lowering the inspection standard of the LSI element on which the operational amplifier is formed at the manufacturing site, the gain and the offset amount are accurately adjusted according to the variation in the reflectance on the irradiation surface of the magneto-optical disk 7 in the adjustment processing of the operational amplifier 22 in the market. In this way, the amplitude of the RF signal S18 obtained by reproducing from the magneto-optical disk 7 can be correctly analog-digital converted. It can be adjusted to.
[0071]
Further, in the disk recording / reproducing apparatus 1, the gain adjustment value and the offset amount adjustment value obtained at the time of the adjustment process of the operational amplifier 22 in the market and the adjustment process of the operational amplifier 22 at the factory are used as the initial values of the gain and the offset amount of the operational amplifier 22. Since the setting value is set, the adjustment process of the operational amplifier 22 in this market is performed rather than setting the initial value of the gain and the offset amount preset according to the standard to the operational amplifier 22 during the adjustment process of the operational amplifier 22 in the factory. The time required for the recording / reproducing apparatus 1 can be greatly shortened, and the start-up time in the reproduction mode of the disk recording / reproducing apparatus 1 can be reduced (for example, about 100 [ms]).
[0072]
In addition to this, the disc recording / reproducing apparatus 1 controls the moving amount of the optical block 9 while detecting the moving distance and moving direction of the optical block 9 by the linear scale and the linear encoder 17. A conventional disk recording / reproducing apparatus (not shown) that reproduces only the magneto-optical disk 7 having a recording density of 1 to 4 times, but is not configured to detect the moving distance and moving direction of the optical block 9. ), The format information can be easily and accurately read out from the PEP of the magneto-optical disk 7 in a short time, thereby further increasing the start-up time of the disk recording / reproducing apparatus 1 in the reproduction mode (for example, as a whole). About 500 [ms]).
[0073]
According to the above configuration, the factory performs the adjustment process of the operational amplifier 22 using the first amplitude threshold value and the first offset threshold value for the factory, which are relatively small values, and the market. Then, the second amplitude threshold value set to a value larger than the first amplitude threshold value and the first offset threshold value in accordance with the variation in the reflectance of the irradiated surface of the magneto-optical disk 7; By adjusting the operational amplifier 22 using the second offset threshold value, the irradiation of the magneto-optical disk 7 can be performed in the market without lowering the inspection standard of the LSI element on which the operational amplifier is formed at the factory. Even when there is a variation in reflectance on the surface, the RF signal S1 obtained by reproducing from the magneto-optical disk 7 by accurately adjusting the gain and offset amount of the operational amplifier 22 The amplitude, correctly it can be adjusted to be analog-to-digital conversion, thus it is possible to realize an adjustment method which can greatly reduce the occurrence of reproduction errors for the magneto-optical disc in the market.
[0074]
(4) Other embodiments
  In the above-described embodiment, the first amplitude threshold and the first offset threshold are set to about 10 to 30% in accordance with the variation in reflectance on the irradiation surface of the magneto-optical disk 7, respectively. bigIn valueShiTheAlthough the case where the second amplitude threshold value and the second offset threshold value are set is described, the present invention is not limited to this, and the variation in reflectance on the irradiation surface of the magneto-optical disk 7 is described. In addition, the second amplitude threshold and the second offset threshold may be set by adding environmental conditions such as temperature and / or dust.
[0075]
In the above-described embodiment, the case where the adjustment processing of the operational amplifier 22 at the manufacturing site is performed in substantially the same manner as the RF signal adjustment processing procedure RT1 shown in FIG. 7 described above has been described. However, in the adjustment process of the operational amplifier 22 at the manufacturing site, when each loop is repeated in accordance with the RF signal adjustment process procedure RT1, the maximum number of repetitions of this loop is greater than the adjustment process of the operational amplifier 22 in the market or A small number may be set.
[0076]
Further, in the above-described embodiment, the case where the present invention is applied to the disk recording / reproducing apparatus 1 for recording / reproducing data on the 5.25 inch magneto-optical disk 7 has been described, but the present invention is not limited thereto. For example, the present invention may be applied to various other reproducing apparatuses such as a disk reproducing apparatus for reproducing data from a disk-shaped recording medium such as a 3.5-inch optical disk.
[0077]
Furthermore, in the above-described embodiment, when adjusting the operational amplifier 22 in the market, the DSP 3 detects the amplitude of the RF signal S18 and the offset amount of the operational amplifier 22 based on the amplitude signal S27 and the offset signal S28 read from the inner register 21. Although the present invention is not limited to this, the DSP 3 captures the RF signal S18 amplified from the operational amplifier 22, and detects the amplitude and the offset amount of the operational amplifier 22 based on the captured RF signal S18. You may do it.
[0078]
Furthermore, in the above-described embodiment, the case where the lead channel 16 is replaced as necessary to adjust the gain and offset amount of the operational amplifier 22 during the adjustment process of the operational amplifier 22 in the shipping inspection has been described. The present invention is not limited to this, and during the adjustment process of the operational amplifier 22 in the shipping inspection, the amplitude of the RF signal S18 is set to be equal to or less than the first amplitude threshold value, and the offset amount is set to be equal to or less than the first offset threshold value. When it is difficult to adjust the gain and offset amount of the operational amplifier 22 as described above, circuits other than the lead channel 16 such as the DSP 3 may be replaced, or the disk recording / reproducing apparatus 1 may be stopped from shipping.
[0079]
Further, in the above-described embodiment, during the adjustment process of the operational amplifier 22 in the shipping inspection, the gain adjustment value and the offset adjustment value are detected by using the magneto-optical disk 7 which is actually 8 times denser, and 1 time. Although the case where the adjustment value of the gain of the operational amplifier 22 and the adjustment value of the offset amount in the magneto-optical disk 7 from dense to quadruple density are obtained based on a predetermined conversion formula has been described, the present invention is not limited to this. During the adjustment process of the operational amplifier 22 in the shipping inspection, the gain adjustment value and the offset amount adjustment value are actually detected using all the magneto-optical disks 7 from 1 to 8 times dense. May be.
[0080]
Further, in the above-described embodiment, the case where the adjustment processing of the operational amplifier 22 using the second amplitude threshold value and the second offset threshold value is performed in the market has been described. However, if the shipment inspection has been completed, the second amplitude threshold value and the second amplitude threshold are set when data is reproduced from the magneto-optical disk 7 by the disk recording / reproducing apparatus 1 regardless of the market or the factory. Adjustment processing of the operational amplifier 22 using the second offset threshold value may be performed.
[0081]
【The invention's effect】
  As described above, according to the present invention,In the reproduction accuracy adjustment method for adjusting the reproduction accuracy of the disc-shaped recording medium by the reproduction device by the adjustment means provided in the reproduction device, the adjustment device of the reproduction device includes:Disc-shaped recording mediumthe body'sA first step of adjusting the reproduction accuracy at the time of shipping inspection so as to be within a predetermined first range;Adjustment meansA second step of adjusting the reproduction accuracy after the shipping inspection so as to be within a predetermined second range in which the first range is relaxed, and in the first step,Adjustment meansThe amplitude of a reproduction signal obtained by reproducing from a disk-shaped recording medium representing the reproduction accuracy,The playback device remembersThe gain and offset amount of the operational amplifier so as to be within a first range that is less than or equal to a predetermined first threshold value.At least one ofAnd in the second step,Adjusting means of the playback deviceThe amplitude of the reproduction signal is larger than the first threshold valueThe playback device remembersThe gain and offset amount of the operational amplifier so as to be within the second range below the predetermined second threshold value.At least one ofAnd the second threshold value is increased by about 10 to 30% in accordance with the variation in the reflectance on the laser light irradiation surface of the disk-shaped recording medium. Even if there is a variation in the reflectivity on the laser light irradiation surface of the disk-shaped recording medium after this shipping inspection, without reducing the inspection standard at the time of shipping inspection of the playback device, The playback accuracy can be adjusted, and thus the occurrence of playback errors on disc-shaped recording media can be greatly reduced.Playback accuracy by playback deviceAdjustment method andRegenerationAn apparatus can be realized.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of the configuration of a disk recording / reproducing apparatus according to the present invention.
FIG. 2 is a block diagram for explaining an RF signal amplitude adjustment process;
FIG. 3 is a schematic conceptual diagram for explaining erasure of data recorded on a magneto-optical disk.
FIG. 4 is a schematic conceptual diagram for explaining the recording of data on a magneto-optical disk.
FIG. 5 is a schematic conceptual diagram for explaining the reproduction of data recorded on a magneto-optical disk.
FIG. 6 is a waveform diagram for explaining the light intensity of the reflected light before and after the analyzer.
FIG. 7 is a flowchart showing an RF signal adjustment processing procedure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Disk recording / reproducing apparatus, 2 ... Controller, 3 ... DSP, 7 ... Magneto-optical disk, 16 ... Reed channel, 21 ... Inner register, 22 ... Operational amplifier, 23 ... Analog digital converter, RT1 ... RF signal adjustment processing procedure, S18 ... RF signal, S25 ... Gain control signal, S26 ... Offset amount control signal, S27 ... Amplitude signal, S28 ... Offset signal.

Claims (3)

A reproduction accuracy adjustment method for adjusting the reproduction accuracy of a disc-shaped recording medium by the reproduction device by an adjusting means provided in the reproduction device,
A first step of the adjustment means of the reproducing apparatus is adjusted at the factory inspection so that within a first range of the reproduction accuracy of a given said disc-shaped recording medium,
A second step in which the adjusting means of the playback device adjusts the playback accuracy after the shipping inspection so that the playback accuracy is within a predetermined second range that is less than the first range;
In the first step,
The amplitude of a reproduction signal obtained by the adjustment means of the reproduction device being reproduced from the disk-shaped recording medium representing the reproduction accuracy is equal to or less than a predetermined first threshold value stored in the reproduction device. Adjust at least one of the gain and offset amount of the operational amplifier to be within the first range,
In the second step,
The adjustment means of the reproduction apparatus has an amplitude of the reproduction signal larger than the first threshold value and within a second range that is equal to or less than a predetermined second threshold value stored in the reproduction apparatus . Adjusting at least one of the gain and the offset amount of the operational amplifier so that
The second threshold is
A reproducing apparatus characterized in that the first threshold value is increased by about 10 to 30% in accordance with at least a variation in reflectance on the laser light irradiation surface of the disk-shaped recording medium. The playback accuracy adjustment method by. In the second step,
An adjustment value of said adjustment means the gain obtained in the first step to the operational amplifier of the playback apparatus sets an adjustment value of the offset amount as an initial value, the upper Symbol reproduction accuracy the second The method according to claim 1, wherein at least one of the gain and the offset amount of the operational amplifier is adjusted so as to be within a range. The playback accuracy during shipping inspection of the disk-shaped recording medium was adjusted to be within a predetermined first range, the second range on the Symbol reproduction accuracy of a predetermined with relaxed first range above after shipment inspection and adjustment means for adjusting so that,
A predetermined first threshold value used for adjusting the reproduction accuracy at the time of the shipping inspection and a predetermined first threshold value larger than the first threshold value used for adjusting the reproduction accuracy after the shipping inspection. Storage means for storing two threshold values;
With
The adjusting means is
Gain of the operational amplifier so that the upper Symbol within the first range of the amplitude becomes below said first threshold value of a reproduction signal obtained by reproducing from the disc-shaped recording medium that represents the reproduction accuracy during the shipping inspection and adjusting at least one of the offset amount, the gain and the offset of the operational amplifier so after the shipping inspection falls within the second range of the amplitude of the reproduction signal below the upper Symbol second threshold Adjust at least one of the quantity,
The second threshold is
A reproducing apparatus characterized in that the first threshold value is increased by about 10 to 30% in accordance with at least a variation in reflectance on the laser light irradiation surface of the disk-shaped recording medium. .

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