JP4517546B2 - Optical pickup adjusting device and optical pickup adjusting method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical pickup adjustment apparatus and adjustment method used for adjustment of an optical pickup capable of recording / reproducing plural types of optical disks.
[0002]
[Prior art]
Some optical pickups are capable of recording and reproducing two types of optical discs having different physical formats, such as a compact disc (CD) and a digital versatile disc (DVD). The optical pickup capable of recording and reproducing these two types of optical discs condenses the light beam emitted from the light source and the light source emitting a 780 nm light beam for CD and a 635-650 nm light beam for DVD. A bifocal objective lens, a photodetector for detecting a returning light beam reflected by the signal recording surface of a CD or DVD, an objective lens driving unit for driving and displacing the objective lens in the focusing direction and the tracking direction, and the like are provided. .
[0003]
The objective lens drive unit includes a lens holder that holds the objective lens, a holder support member that supports the lens holder so that the lens holder can be displaced in the focusing direction and the tracking direction, and a lens holder that holds the objective lens in the focusing direction. A focusing drive unit that drives and displaces and a tracking drive unit that drives and displaces the lens holder holding the objective lens in the tracking direction.
[0004]
The focusing drive unit includes a focusing coil and a focusing magnet, and the lens holder held on the elastic support member by the action of the current flowing in the focusing coil and the magnetic field generated by the focusing magnet is in the direction of the optical axis of the objective lens. Drive displacement in the direction. The tracking drive unit includes a tracking coil and a tracking magnet. The lens holder supported by the elastic support member by the action of the current flowing through the tracking coil and the magnetic field generated by the tracking magnet is orthogonal to the optical axis of the objective lens. Drive displacement in the direction of
[0005]
In the optical pickup as described above, the objective lens is driven and displaced by the focusing drive unit so that the light beam emitted from the light source is focused on the signal recording surface of the optical disc, and the objective lens is moved in the tracking direction by the tracking drive unit. By displacing the drive, the light beam is scanned, and the information signal recorded on the CD or DVD is read.
[0006]
The optical pickup configured as described above is further attached to a base unit for assembly to a recording and / or reproducing apparatus. This base unit has a base assembled to the housing of the recording and / or reproducing apparatus, and a slide member to which the optical pickup is assembled and a slide member to which the optical pickup is assembled are sent to the base in the radial direction of the optical disc. A feeding mechanism for operation and a disk rotation driving mechanism for rotating the optical disk are provided.
[0007]
Incidentally, in the optical pickup assembled in the assembly process, the relative position between the objective lens and the light source and the inclination of the optical axis of the objective lens are adjusted. This adjustment is performed after the optical pickup is assembled to the base unit, for example, and does not depend on the accuracy of assembly of the optical pickup to the base unit, compared to the adjustment performed before assembly of the optical pickup to the base unit. The relative position between the objective lens and the light source and the inclination of the optical axis of the objective lens can be adjusted.
[0008]
This adjustment is performed for each of CD and DVD. Specifically, first, an adjustment optical disk for CD is mounted on a disk rotation driving mechanism, and the adjustment optical disk for CD is rotated, and the relative relationship between the objective lens and the light source is set so that the optical characteristic becomes an optimum value. Adjust the target position. Next, the adjustment optical disk for DVD is mounted on the disk rotation drive mechanism, the adjustment optical disk for DVD is rotated, and the relative positions of the objective lens and the light source are adjusted so that the optical characteristics become the optimum values. Do. Thereafter, the tilt of the objective lens is adjusted using an adjustment optical disk for DVD.
[0009]
Here, the adjustment optical disk for CD is recorded in a spiral shape with 8-14 modulated data in the same physical format as the CD, and the adjustment optical disk for DVD is the same physical format as the DVD, that is, Data that has been modulated 8-16 in a physical format of higher density recording than the physical format of a CD is recorded in a spiral shape.
[0010]
[Problems to be solved by the invention]
As described above, in the adjustment of the optical pickup used for recording and reproduction of both the CD and DVD optical disks, the CD adjustment optical disk is mounted on the disk rotation drive mechanism when adjusting the optical characteristics when reproducing the CD. When adjusting the optical characteristics when reproducing a DVD, it is necessary to mount an adjustment optical disk for DVD on the disk rotation drive mechanism. Such adjustment requires replacement of the optical disk for adjustment, and it is difficult to further improve the efficiency of the adjustment work of the optical pickup.
[0011]
Also, this adjustment is performed by the light source or optical system held by the light source adjustment mechanism of the adjustment device in a state where the slide member for feeding the optical pickup and the lens holder or holder support member for holding the objective lens are held with high accuracy. Adjustments are made. At this time, the slide member, the holder support member, and the light source are held separately, and are adjusted by moving these parts by a relatively small amount. It is difficult to perform the feeding operation.
[0012]
However, as described above, data is recorded in a spiral shape on any of the adjustment optical disks. Therefore, when data is read from the recording track of the adjustment optical disk while the adjustment optical disk is rotated during adjustment, the objective lens gradually moves in the outer circumferential direction as the adjustment optical disk rotates. As a result, during adjustment, the objective lens of the optical pickup moves toward the outer periphery of the optical disk for adjustment, and the objective lens changes from the state of zero field swing to the state of field swing. The optical axis of the objective lens is displaced with respect to the center (hereinafter referred to as the optical center). In this adjustment method, since the optical characteristic of the objective lens is deviated from the optical center, the optical characteristics are deteriorated and the jitter value of the reproduced signal to be detected is also deteriorated. It is very difficult to adjust the inclination of the optical axis of the objective lens by measuring the change of the reproduction signal by inclining and adjusting it to the best point.
[0013]
As a method to solve such problems, when the optical axis of the objective lens has a predetermined misalignment with respect to the optical center, the feed mechanism is operated and the tracking servo is removed to adjust the misalignment amount. There is a method in which the optical axis of the objective lens is always within a predetermined positional deviation range with respect to the optical center by performing a feeding operation (hereinafter referred to as track jump) to the inner circumference side of the optical disc for use.
[0014]
However, in this method, since the optical axis and the optical center of the objective lens are constantly moving, it is difficult to detect a true value at the time of adjustment. In addition, while this method takes a short time until tracking servo is applied, it takes time for a stable true value to be measured by a measuring device such as a jitter detector. The time during which the position of the optical axis of the lens can be adjusted becomes very short, making adjustment difficult. Further, in this method, when the track jump interval is widened, the positional deviation of the optical axis of the objective lens is further increased.
[0015]
Further, the adjustment device that performs this adjustment is data that is 8-14 modulated data read from the CD adjustment optical disk, and data that is read from the DVD adjustment optical disk is 8-16 modulated. Therefore, it is necessary to provide a signal processing circuit including two demodulation circuits and the like, and the configuration of the reproduction system is complicated.
[0016]
The present invention has been made in view of the above-described problems, and an object of the present invention is to simplify and quickly adjust an optical pickup that can perform recording and reproduction of different types of optical disks. It is an object to provide an adjustment apparatus and method.
[0017]
[Means for Solving the Problems]
  According to the present inventionA first optical disk in which data modulated by the first modulation method is recorded in the first physical format and a second optical disk in which data modulated by the second modulation method is recorded in the second physical format. PlayIn order to solve the above-described problems, the optical pickup adjusting deviceFirst signal recording layer and second signal recording layerIn each signal recording layer, data modulated by the same modulation method is recorded concentrically in different physical formats.The recording area where the data of each signal recording layer is recorded is provided so as not to overlap each other.An optical disk for adjustment of the optical pickup is mounted, a disk rotating mechanism for rotating the optical disk for adjustment, and a light beam emitted from the light source is condensed by an objective lens, and a return light beam reflected by the optical disk for adjustment is optically reflected. The optical pickup is detected by the detector, and the objective lens is displaced by the objective lens drive unit in a direction perpendicular to the optical axis direction of the objective lens and the optical axis. Moving means for moving; and adjusting means for adjusting the relative position of the light source and the objective lens and the inclination of the optical axis of the objective lens;A demodulator for demodulating the data recorded in the first and second signal recording layers detected by the photodetector of the optical pickupIs provided.
In the adjustment optical disk, data modulated by the first modulation method is recorded on the first signal recording layer in the first physical format, and modulated on the second signal recording layer by the first modulation method. Data is recorded in the second physical format. Further, the first modulation method is a modulation method having a smaller number of bits after modulation than the second modulation method. The demodulator demodulates the data recorded on the first and second signal recording layers modulated by the first modulation method.
When the optical pickup is moved to the first position by the moving means, the relative position between the light source and the objective lens is adjusted by the adjusting means by irradiating one of the signal recording layers of the adjustment optical disk with the light beam. When the optical signal is moved to a second position different from the first position, the relative position between the light source and the objective lens is adjusted by the adjusting means by irradiating the other signal recording layer of the adjustment optical disc with a light beam.
[0018]
  Further, according to the present inventionA first optical disk in which data modulated by the first modulation method is recorded in the first physical format and a second optical disk in which data modulated by the second modulation method is recorded in the second physical format. PlayIn order to solve the above-described problems, the optical pickup adjustment method condenses the light beam emitted from the light source with the objective lens, and detects the return light beam reflected by the adjustment optical disk with the photodetector. Installing an optical pickup that displaces the objective lens by an objective lens drive unit in a direction orthogonal to the optical axis direction of the objective lens and the optical axis so that the light source can move with respect to the objective lens; ,A first signal recording layer and a second signal recording layer;In each signal recording layer, data modulated by the same modulation method is recorded concentrically in different physical formats.The recording area where the data of each signal recording layer is recorded is provided so as not to overlap each other.Mounting the optical disk for adjusting the optical pickup on the disk rotating mechanism, and moving the optical pickup to the first position by the moving means;on the other handAdjusting the relative position of the light source and the objective lens by irradiating the signal recording layer with a light beam, and moving the optical pickup to a second position different from the first position by the moving means,The otherAdjusting the relative position of the light source and the objective lens and the inclination of the optical axis of the objective lens by irradiating the signal recording layer with a light beam;Demodulating the data recorded on the first and second signal recording layers detected by the photodetector of the optical pickup;Have
  In the adjustment optical disk, data modulated by the first modulation method is recorded on the first signal recording layer in the first physical format, and modulated on the second signal recording layer by the first modulation method. Data is recorded in the second physical format, and the first modulation method is a modulation method having a smaller number of bits after modulation than the second modulation method. Then, the data recorded in the first and second signal recording layers modulated by the first modulation method is demodulated.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an optical disk for adjusting an optical pickup to which the present invention is applied, an optical pickup adjusting apparatus using the adjusting optical disk, and an optical pickup adjusting method using the adjusting apparatus will be described with reference to the drawings.
[0020]
As shown in FIG. 1, an optical disk for adjusting an optical pickup 1 is an adjusting optical disk used for adjusting an optical pickup capable of reproducing both a CD and a DVD, and has an optical transparency of 0.6 mm in thickness. A first disk substrate 2 having a light transmitting property and a second disk substrate 3 having a light transmitting property are bonded to each other with a light transmissive adhesive 4.
[0021]
The first disk substrate 2 is provided with a first signal recording layer 5 on one surface side. The first signal recording layer 5 is used when adjusting the optical pickup during CD reproduction. Therefore, the first signal recording layer 5 is 1.2 mm from the signal reading surface side so that the physical format is the same as that of the CD. In place. The first signal recording layer 5 has the same modulation method as CD, that is, 8-14 modulated data, in a pit pattern with a track pitch of 1.6 μm and a pit length of 0.9 to 3.3 μm. It is recorded. Here, the recording track T provided in the first signal recording layer 5 is formed concentrically, whereas the recording track of a normal optical disk is formed in a spiral shape from the inner peripheral side to the outer peripheral side. When adjusting the optical pickup, the optical pickup is prevented from moving in the radial direction. A reflective film, a protective film, and the like are formed on the first signal recording layer 5, and a label 6 is provided on the protective film.
[0022]
The second disk substrate 3 is provided with a second signal recording layer 7 on one surface side. This second signal recording layer 7 is used when adjusting the optical pickup during DVD reproduction. Therefore, the signal reading surface side is 0.6 mm from the side so that the physical format is the same as that of the DVD. In place. Further, the second signal recording layer 7 records the same modulation method as that of CD, that is, 8-14 modulated data in a pit pattern with a track pitch of 0.74 μm and a pit length of 0.4 to 1.87 μm. Has been. Here, the DVD originally uses a modulation method different from that of the CD, specifically, the 8-16 modulation method. However, since the adjustment optical disc 1 is an optical disc for adjustment of an optical pickup, data is not stored. Basically, there is no need to demodulate, and therefore, the second signal recording layer 7 records 8-14 modulated data as with the CD. That is, in the adjustment optical disc 1, by using a modulation method with a small number of bits after modulation, that is, 8-14 modulation, as a modulation method, processing such as demodulation processing can be lightened. Further, the recording track T provided in the second signal recording layer 7 is also formed concentrically, whereas the recording track of a normal optical disc is formed in a spiral shape from the inner peripheral side to the outer peripheral side, When adjusting the optical pickup, the optical pickup is prevented from moving in the radial direction.
[0023]
Since the adjustment data is signal-processed and recorded in accordance with the CD standard in the first and second signal recording layers 5 and 7, the adjustment data is cross-interleaved Solomon as an error correction code. A code (CIRC: Cross Interleave Reed-Solomon Code) may be added. Further, as an error correction code, a Reed Solomon Product Code (RS-PC) adopted in DVD may be added.
[0024]
By the way, as shown in FIG. 2, the adjustment optical disk 1 has the adjustment data recorded in the first recording area 8 and the second signal recording layer 7 of the adjustment data recorded in the first signal recording layer 5. The second recording area 9 for data is provided so as to at least partially overlap. That is, the adjustment optical disk 1 is provided with the first recording area 8 and the second recording area 9 in a range that can be followed by tracking control of the objective lens. For example, the adjustment optical disk 1 is provided with a recording area to be read first on the inner peripheral side of the adjustment optical disk 1 so that the end of this recording area and the start of the other recording area overlap at least. Alternatively, the two recording areas may be completely overlapped. As described above, the adjustment optical disc 1 is provided so that at least a part of the first recording area 8 and the second recording area 9 overlap each other, so that the optical pickup is fed when the signal recording layer to be reproduced is switched. There is no need, and the optical pickup can be adjusted efficiently.
[0025]
Further, as shown in FIG. 3, the first recording area 8 and the second recording area 9 provided on the adjustment optical disc 1 may be provided so as not to overlap each other. In this case, the recording track provided in the first signal recording layer 5 and the recording track provided in the second signal recording layer 7 do not overlap. For example, the first signal recording layer 5 has a first track. When the recording area 8 is reproduced, the data can be reliably read out.
[0026]
As described above, since the adjustment optical disc 1 has the recording tracks provided in the first signal recording layer 5 and the second signal recording layer 7 in a concentric manner, at least one of the signal recording layers is provided. During reproduction, it is not necessary to move the optical pickup in the radial direction of the adjustment optical disc 1, and the optical pickup can be adjusted efficiently. Further, since adjustment data of the same modulation system of the first signal recording layer 5 and the second signal recording layer 7 is recorded on the adjustment optical disc 1, for example, a signal from a demodulation circuit of the adjustment device or the like The processing circuit can be shared, and by adopting the 8-14 modulation method, processing such as demodulation of 8-16 modulation can be lightened.
[0027]
Next, a configuration of an optical pickup capable of recording and / or reproducing a CD and a DVD used in the present invention will be described with reference to FIG.
[0028]
As shown in FIG. 4, the optical pickup 11 is emitted from a light source 12 such as a semiconductor laser that emits a light beam having a wavelength of 780 nm for CD and a light beam having a wavelength of 635 to 650 nm for DVD. The bifocal objective lens 13 for condensing the collected light beam on the first signal recording layer 5 and the second signal recording layer 7 of the adjustment optical disc 1 and the return light beam reflected by the adjustment optical disc 1 A photodetector 14 that receives light, a beam splitter 15 that guides the light beam emitted from the light source 12 to the objective lens 13, and guides the returned light beam reflected by the adjustment optical disk 1 to the photodetector 14, and the objective lens 13. Is provided with an objective lens driving unit 16 that is driven and displaced in the focusing direction and the tracking direction.
[0029]
The objective lens 13 is, for example, a hologram integrally formed on the lens. When reproducing a CD, that is, when irradiating the first signal recording layer 5 with a light beam, the objective lens 13 transmits the transmitted light to the first signal recording. When the layer 5 is focused and the DVD is reproduced, that is, when the second signal recording layer 7 is irradiated with the light beam, the diffracted light is focused on the second signal recording layer 7. The objective lens 13 is held by a lens holder 17, and the lens holder 17 is attached to a holder support member 18 via an elastic support member. The lens holder 17 holding the objective lens 13 is supported by an elastic support member so that it can be displaced in a focusing direction which is the optical axis direction of the objective lens 13 and a tracking direction orthogonal to the optical axis direction of the objective lens 13. Thus, it is supported by the holder support member 18.
[0030]
The objective lens driving unit 16 includes a focusing driving unit that drives and displaces the objective lens 13 in the focusing direction, and a tracking driving unit that drives and displaces the objective lens 13 in the tracking direction. Each driving unit includes a lens holder. A coil attached to the 17 side and a magnet attached to the holder support member 18 side are provided. Each driving unit drives and displaces the objective lens 13 held by the lens holder 17 in the focusing direction and the tracking direction by the action of the current flowing in the coil and the magnetic field generated by the magnet. Thus, the light beam emitted from the light source 12 is scanned by the objective lens driving unit 16 and the like, focused on the signal recording layer of the CD or DVD, and the returned light beam reflected by the signal recording layer is used as the photodetector 14. By detecting the information signal, the information signal can be reliably read out.
[0031]
The optical pickup 11 configured as described above is further attached to a base unit 21 for assembling to a recording and / or reproducing apparatus. The base unit 21 has a base 22 that is assembled to the housing of the recording and / or reproducing apparatus, and a slide member 23 that is assembled with the optical pickup 11 and a slide member 23 that is assembled with the optical pickup 11. Is provided with a feeding mechanism 24 that feeds the optical disk in the radial direction of the optical disk, and a disk rotation driving mechanism 25 that rotationally drives the optical disk.
[0032]
The slide member 23 is to which the optical pickup 11 is attached, and is disposed in an opening 28 provided in the base 22 along the radial direction of the optical disk. In this slide member 23, for example, a positioning pin on the slide member 23 side is engaged with a positioning hole provided in the holder support member 18, and the holder support member 18 constituting the optical pickup 11 is positioned with high accuracy by an adhesive. It will be fixed in the state.
[0033]
The feed mechanism 24 includes, for example, a drive motor 26 attached to the base 22 and a feed screw 27 connected to the drive motor 26 via a plurality of gear trains. The feed screw 27 is rotatably attached to the base 22 along the moving direction of the optical pickup 11, that is, the radial direction of the optical disk. The feed screw 27 is engaged with the engagement protrusion of the slide member 23 to which the optical pickup 11 is attached in the thread groove provided on the peripheral surface thereof. As a result, the slide member 23 to which the optical pickup 11 is attached moves in the radial direction of the optical disc when the feed screw 27 is rotated by the drive motor 26.
[0034]
The disk rotation drive mechanism 25 has a drive motor 29 disposed on the back side of the base 22 and a disk table 30 attached to the drive shaft of the drive motor 29. The disc table 30 centers the optical disc by engaging with the center hole of the optical disc, and rotates the optical disc integrally. The drive motor 29 rotates the DVD so that the linear velocity is, for example, 3.49 m / sec defined in the DVD standard during DVD reproduction, and the linear velocity is defined in the CD standard defined in the CD standard, for example, during CD reproduction. The CD is rotated so that the speed is 2 to 1.4 m / sec.
[0035]
By the way, as shown in FIG. 4, the adjusting device 41 for adjusting the optical pickup 11 assembled to the base unit 21 is in a state where the base unit 21 having the optical pickup 11 assembled to an adjustment base (not shown) is positioned. Retained. The adjustment device 41 holds the holder support member 18 of the optical pickup 11 and holds the objective lens adjustment mechanism 42 that adjusts the position of the objective lens 13, the base holding mechanism 43 that holds the base 22, and the slide member 23. A slide member holding mechanism 44 that holds the light source 12 and adjusts the position of the light source 12, and a light detector adjustment mechanism 46 that holds the light detector 14 and adjusts the position of the light detector 14. And a detection mechanism 47 for detecting the optical characteristics of the light beam emitted from the light source 12.
[0036]
The adjustment base for holding the base unit 21 has a plurality of positioning shafts for positioning the base 22, and the base 22 is positioned by engaging these positioning shafts with positioning holes provided in the base 22. Hold in state.
[0037]
The objective lens adjustment mechanism 42 has a pair of holding arms that hold the holder support member 18, and holds the holder support member 18 by the pair of holding arms during adjustment. Then, the pair of holding arms holding the holder support member 18 is in a radial direction (X direction) parallel to the radial direction of the adjustment optical disc 1 and in the radial direction of the adjustment optical disc 1 while holding the holder support member 18. Translate in the orthogonal tangential direction (Y direction). In addition, the pair of holding arms tilts the objective lens 13 in the radial direction with respect to the optical axis and the objective lens 13 in the tangential direction with respect to the optical axis while holding the holder support member 18. Adjust the tangential skew. The pair of holding arms moves the objective lens 13 in the optical axis direction in order to adjust the optical path length to the light source 12 and the adjustment optical disc 1. Thus, the holder support member 18 can adjust the plane direction parallel to the optical disk for adjustment 1, the optical axis direction of the objective lens 13 orthogonal to the plane, and the inclination of the objective lens 13 with high accuracy by the pair of holding arms. Done. At this time, the holder support member 18 is slightly lifted with respect to the slide member 23, and the gap formed between the slide member 23 and the holder support member 18 is filled with an adhesive, whereby the slide member It is fixed in a state of being positioned with high accuracy with respect to 23.
[0038]
The base holding mechanism 43 has a pair of holding arms that hold the feed screw 27 that constitutes the feed mechanism 24 provided on the base 22. When adjusting the optical pickup, the pair of holding arms hold both ends of the feed screw 27 so that the feed screw 27 is not bent and deformed, so that the adjustment position of the optical pickup 11 is not shifted.
[0039]
The slide member holding mechanism 44 has a plurality of positioning pins for preventing the slide member 23 from moving along the feed screw 27, and these positioning pins are provided on the slide member 23 when the optical pickup 11 is adjusted. By engaging the positioning hole, the slide member 23 is held at a predetermined position in the radial direction of the adjustment optical disc 1 with high accuracy.
[0040]
The light source adjustment mechanism 45 has a light source holding arm that holds the light source 12 disposed in the optical pickup 11. When adjusting the optical pickup 11, the light source holding arm holds the light source 12 in a positioned state, and moves so that the center of the light source 12 coincides with a fixed point on the optical axis of the objective lens 13. The light source holding arm rotates the light source 12 around the light emitting point of the light source 12. Further, the light source holding arm moves in the optical axis direction of the objective lens 13 in order to adjust the optical path length from the light source 12 to the adjustment optical disc 1.
[0041]
The photodetector adjustment mechanism 46 has a photodetector holding arm that holds the photodetector 14 disposed in the optical pickup 11. The photodetector holding arm holds the photodetector 14 in a positioned state when the optical pickup 11 is adjusted, and moves so that the center of the photodetector 14 coincides with a fixed point on the optical axis of the objective lens 13. . The photodetector holding arm rotates the photodetector 14. Further, the photodetector holding arm moves the photodetector 14 in the optical axis direction in order to adjust the optical path length.
[0042]
The detection mechanism 47 includes a CCD (Charge-Coupled Devices) camera 48 that detects a light beam emitted from the objective lens 13 and a coma aberration determination unit 49 that detects coma aberration. The CCD camera 48 is positioned on the optical axis of the objective lens 13 by a moving mechanism (not shown), detects the light beam, and outputs the detection result to the coma aberration determination unit 49. Then, the coma aberration determination unit 49 detects the minimum value of the coma aberration.
[0043]
As shown in FIG. 4, the adjustment device 41 displays a signal detection unit 51 that detects a reproduction signal output from the photodetector 14 of the optical pickup 11 and a signal detected by the signal detection unit 51. A display unit 52; a drive control unit 53 that controls the drive motor 26 that forms the disk rotation drive mechanism 25 of the base unit 21; and a drive control unit 54 that controls the drive motor 29 that forms the feed mechanism 24 of the optical pickup 11. And an output control unit 55 for controlling the output of the light beam of the light source 12 and a controller 56 for controlling the overall operation. Based on the determination result from the coma aberration determination unit 49 and the input from the signal detection unit 51, the controller 56 drives the drive control units 53 and 54, the output control unit 55, the objective lens adjustment mechanism 42, and the light source adjustment mechanism 45. Control of the photodetector adjustment mechanism 46 and the like is performed.
[0044]
Furthermore, the adjustment device 41 includes a demodulation unit 57 that demodulates the signal detected by the signal detection unit 51, and an error correction processing unit 58 that performs error correction processing on the demodulated data. The adjusting device 41 uses the adjusting optical disc 1 shown in FIGS. 1 to 3. The adjusting optical disc 1 includes an 8-optical disc on the first signal recording layer 5 and the second signal recording layer 5. In 14 modulation schemes, adjustment data to which CIRC is added as an error correction code is recorded. That is, the first signal recording layer 5 and the second signal recording layer 7 are recorded with data modulated by the same modulation method and subjected to error correction coding processing of the same method. Therefore, the demodulator 57 demodulates 8-14 modulated data read from the first signal recording layer 5 and the second signal recording layer 7, and the error correction processor 58 demodulates the data. Error correction processing is performed based on the CIRC of the received data. For example, the error correction processing unit 58 outputs the error rate to, for example, an inspection device for inspecting the error rate. That is, the adjustment device 41 does not need to be provided with a demodulation unit that demodulates 8-16 modulated data for DVD or an error correction processing unit that performs RS-PC error correction decoding processing.
[0045]
The relative position between the light source 12 and the objective lens 13 of the optical pickup 11 using the adjustment device 41 of the optical pickup 11 and the adjustment optical disc 1 configured as described above and the position and inclination of the objective lens 13 with respect to the optical axis are adjusted. A method will be described.
[0046]
First, the base unit 21 is installed on the adjustment base. At this time, the base unit 21 is held in a state of being positioned with high accuracy on the adjustment base by engaging the positioning shaft with the positioning hole provided in the base 22. Further, the slide member holding mechanism 44 is a state in which the slide member 23 is accurately positioned at a predetermined position in the radial direction of the adjustment optical disc 1 by engaging the positioning pins with the positioning holes provided in the slide member 23. Hold on. Furthermore, the base holding mechanism 43 holds the feed screw 27 with a pair of holding arms so as not to rotate so that the optical pickup 11 does not deviate from the adjustment position. The optical pickup 11 is placed and combined with the optical pickup adjusting device 41 on a slide member 23 that is movably assembled on the base unit base 22 via a feed screw 27.
[0047]
The holder support member 18 of the optical pickup 11 placed on the slide member 23 is held by a pair of holding arms of the objective lens adjustment mechanism 42, so that the position of the objective lens 13 is 3 with respect to the slide member 23. Dimensionally positioned. The light source 12 is held by a light source holding arm constituting the light source holding mechanism 45, and the photodetector 14 is held by a photodetector holding arm constituting the light receiving part holding mechanism 46.
[0048]
The adjustment device 41 first adjusts the position of the light source 12 and the objective lens 13. That is, as shown in FIG. 5, in step S1, the controller 56 emits a light beam having a wavelength for CD of 780 nm or a light beam having a wavelength for DVD of 635 to 650 nm from the light source 12 in step S1. To control. As a result, a light beam having a wavelength for CD of 780 nm or a light beam having a wavelength for DVD of 635 to 650 nm is emitted from the light source 12. At this time, the adjustment optical disk 1 is not mounted on the disk table 30 constituting the disk rotation drive mechanism 25.
[0049]
In step S2, the controller 56 adjusts the objective lens 13 with respect to the light source 12, that is, adjusts the position of the objective lens 13 to the designed optical axis. Specifically, the objective lens adjusting mechanism 42 that holds the holder support member 18 drives and controls the holding arm that holds the holder support member 18 based on the control of the controller 56, thereby moving the objective lens 13 in the radial direction (X Direction) and tangential direction (Y direction), and the light source holding mechanism 45 holding the light source 12 moves so that the center of the light source 12 coincides with a fixed point on the optical axis of the objective lens 13. . Thus, the adjustment device 41 moves the positions of the light source 12 and the objective lens 13 and adjusts the position of the objective lens 13 to the designed optical axis.
[0050]
In step S3, the controller 56 performs processing for minimizing coma. In other words, the objective lens adjustment mechanism 42 adjusts the radial skew of the objective lens 13 and the tangential skew of the objective lens 13 by driving and controlling the holding arm holding the holder support member 18 based on the control of the controller 56. The coma aberration is minimized by adjusting the inclination of the objective lens 13 with respect to the optical axis. That is, the CCD camera 48 constituting the detection mechanism 47 detects the light beam collected by the objective lens 13. The controller 56 drives and controls the objective lens adjustment mechanism 42 based on the input from the coma aberration determination unit 49 so that the coma aberration is minimized. When the coma aberration determination unit 49 detects the minimum value of the coma aberration, the controller 56 drives and controls the objective lens adjustment mechanism 42 so as to maintain the position of the objective lens 13 at which the coma aberration is minimized.
[0051]
Thus, the optical pickup 11 is adjusted so that the position of the objective lens 13 coincides with the designed optical axis, and the inclination of the objective lens 13 is adjusted so that the coma aberration is minimized. The relative position of the lens 13 is adjusted. Thereafter, the optical pickup 11 further performs adjustment when reproducing the DVD and adjustment when reproducing the CD, that is, adjusting the relative position between the objective lens 13 and the light source 12 or the photodetector 14. Is called.
[0052]
In step S 4, the adjustment optical disk 1 is mounted on the disk table 30 constituting the disk rotation drive mechanism 25 provided in the base unit 21 installed on the adjustment base, and drive control is performed based on the control of the controller 56. The unit 53 drives the drive motor 29 so that the linear velocity during rotation of the adjustment optical disc 1 is 3.49 m / sec defined by the DVD standard, for example. Here, as shown in FIGS. 1 to 3, the adjustment optical disk 1 mounted on the disk table 30 has the first signal recording layer 5 for adjusting the CD and the second signal recording layer 5 for adjusting the DVD. The signal recording layer 7 is provided, and concentric recording tracks are provided on each of the signal recording layers 5 and 7. The adjustment optical disc 1 shown in FIG. 2 includes a first recording area 8 provided in the first signal recording layer 5 and a second recording area 9 provided in the second signal recording area 7. The adjustment optical disc 1 shown in FIG. 3 is provided so that at least a part thereof overlaps, and the first recording area 8 and the second signal recording area 7 provided in the first signal recording layer 5 are provided. The second recording area 9 is provided so as not to overlap. Further, the data recorded on the first signal recording layer 5 is data that has been modulated 8-14 like the CD, and the adjustment data recorded on the second signal recording layer 7 is for DVD. Modulation data that is 8-14 modulated as adjustment data is recorded.
[0053]
Next, the adjustment of the optical pickup 11 when reproducing the DVD will be described. First, when the adjustment optical disc 1 shown in FIGS. 1 to 3 is mounted on the disc table 30, the optical pickup 11 is first used for the DVD. The second signal recording layer 7 is fed to the position of the second recording area 9. That is, the controller 56 drives the drive motor 26 with the drive control unit 54 and moves the optical pickup 11 to a readable position in the second recording area 9. Then, the drive control unit 53 drives the drive motor 29 so that the linear velocity at the time of rotation of the adjustment optical disc 1 becomes 3.49 m / sec defined by the DVD standard, for example.
[0054]
In step S5, the controller 56 controls the output controller 55 so that the light source 12 emits a light beam having a wavelength of 635 to 650 nm. As a result, a light beam having a wavelength of 635 to 650 nm for DVD is emitted from the light source 12, and the photodetector 14 detects the returning light beam reflected by the adjustment optical disk 1.
[0055]
In step S <b> 6, the adjustment device 41 performs rough adjustment to match the position of the photodetector 14 with the position of the designed optical axis. At this time, the controller 56 controls the objective lens driving unit 16 so that the focusing control and the tracking control are turned off. In this state, the photodetector adjustment mechanism 46 that holds the photodetector 14 moves the photodetector holding arm that holds the photodetector 14 based on the control of the controller 56, and the photodetector Coarse adjustment is performed to match the position of 14 with the position of the designed optical axis.
[0056]
In step S <b> 7, the adjustment device 41 performs rough adjustment for optimizing the optical path length from the light source 12, that is, the light beam emission point to the adjustment optical disc 1. At this time, the controller 56 turns on the focusing control and turns off the tracking control in order to focus the objective lens driving unit 16 on the second signal recording layer 7. This focusing control is performed, for example, by the astigmatism method. The controller 56 controls the objective lens adjustment mechanism 42 that holds the objective lens 13, the light source adjustment mechanism 45 that holds the light source 12, and the light receiving unit detection mechanism 46 that holds the photodetector 14. Then, rough adjustment is performed to optimize the optical path length from the light emitting point of the light beam to the adjustment optical disc 1.
[0057]
In step S8, the adjustment device 41 performs fine adjustment to match the position of the photodetector 14 with the position of the designed optical axis. At this time, the controller 56 turns on both the focusing control and the tracking control so that the objective lens driving unit 16 can scan the concentric recording tracks while the light beam is focused on the second signal recording layer 7. To control. The tracking control is performed by, for example, a push-pull method or a DPD (differential phase detection) method. In this state, the photodetector adjustment mechanism 46 that holds the photodetector 14 moves the photodetector holding arm that holds the photodetector 14 based on the control of the controller 56, and the photodetector Fine adjustment is performed to match the position of 14 with the position of the designed optical axis.
[0058]
In step S9, the adjustment device 41 performs fine adjustment for optimizing the optical path length from the light source 12, that is, the light beam emission point to the adjustment optical disc 1. At this time, the controller 56 turns on both the focusing control and the tracking control so that the objective lens driving unit 16 can scan the concentric recording tracks while the light beam is focused on the second signal recording layer 7. To control. The controller 56 controls the objective lens adjustment mechanism 42 that holds the objective lens 13, the light source adjustment mechanism 45 that holds the light source 12, and the light receiving unit detection mechanism 46 that holds the photodetector 14. Then, fine adjustment is performed to optimize the optical path length from the light beam emission point to the adjustment optical disc 1.
[0059]
Next, the adjusting device 41 adjusts the optical pickup 11 when reproducing the CD. Here, at least one of the adjustment recording optical disk 1 shown in FIG. 2, that is, the first recording area 8 of the first signal recording layer 7 and the second recording area 9 of the second signal recording layer 5 shown in FIG. When the optical discs with overlapping parts are loaded, in step S10, the controller 56 switches the emitted light beam. That is, the output control unit 55 controls the light source 12 so as to emit a 780 nm light beam for CD. The photodetector 14 receives the return light beam reflected by the first signal recording layer 5 of the adjustment optical disc 1. When the adjustment optical disk 1 is mounted on the disk table 30, the optical pickup 11 attached to the slide member 23 is not fed.
[0060]
Further, the adjustment optical disk 1 shown in FIG. 3, that is, the first recording area 8 of the first signal recording layer 5 and the second recording area 9 of the second signal recording layer 7 do not overlap the disk table 30. When the provided optical disk is loaded, the slide member 23 in which the optical pickup 11 is incorporated is fed in the radial direction of the adjustment optical disk 1 to a position where the first recording area 8 can be read. Thereafter, in step S10, the controller 56 switches the emitted light beam. That is, the output control unit 55 controls the light source 12 so as to emit a 780 nm light beam for CD. The photodetector 14 receives the return light beam reflected by the first signal recording layer 5 of the adjustment optical disc 1.
[0061]
Based on the control of the controller 56, the drive control unit 53 drives the drive motor 29 so that the linear velocity at the time of rotation of the adjustment optical disk 1 is 1.2 to 1.4 m / sec determined by the CD standard, for example. Drive.
[0062]
In step S <b> 11, the adjustment device 41 performs rough adjustment to match the position of the photodetector 14 with the position of the designed optical axis. At this time, the controller 56 controls the objective lens driving unit 16 so that the focusing control and the tracking control are turned off. In this state, the photodetector adjustment mechanism 46 that holds the photodetector 14 moves the photodetector holding arm that holds the photodetector 14 based on the control of the controller 56, and the photodetector Coarse adjustment is performed to match the position of 14 with the position of the designed optical axis.
[0063]
In step S <b> 12, the adjustment device 41 performs rough adjustment for optimizing the optical path length from the light source 12, that is, the light beam emission point to the adjustment optical disc 1. At this time, the controller 56 turns on the focusing control and turns off the tracking control in order to focus the objective lens driving unit 16 on the first signal recording layer 5. This focusing control is performed, for example, by the astigmatism method. The controller 56 controls the objective lens adjustment mechanism 42 that holds the objective lens 13, the light source adjustment mechanism 45 that holds the light source 12, and the light receiving unit detection mechanism 46 that holds the photodetector 14. Then, rough adjustment is performed to optimize the optical path length from the light emitting point of the light beam to the adjustment optical disc 1.
[0064]
In step S13, the adjustment device 41 rotates the light source 12 held by the light source holding arm of the light source adjustment mechanism 45 in a state where the adjustment optical disc 1 is driven to rotate by driving the disk rotation drive mechanism 25 of the base unit 21. Move. As a result, the light beam is adjusted so that the ± first-order light is rotated around the optical axis of the zero-order light constituting the three beams, and the phase difference of the ± first-order light is 180 °. The optical pickup 11 can apply tracking servo by the three-beam method based on the output from the photodetector 14 of ± 1st-order light of three beams by the signal detector 51. That is, the optical pickup 11 performs tracking servo based on the output signal from the photodetector 14 that has received the ± first-order light so that the zero-order light of the light beam scans the concentric recording track of the adjustment optical disc 1. Will be able to do.
[0065]
In step S14, the adjustment device 41 performs fine adjustment to match the position of the photodetector 14 with the position of the designed optical axis. At this time, the controller 56 turns on both the focusing control and the tracking control so that the objective lens driving unit 16 can scan the concentric recording tracks while the light beam is focused on the first signal recording layer 5. To control. In this state, the photodetector adjustment mechanism 46 that holds the photodetector 14 moves the photodetector holding arm that holds the photodetector 14 based on the control of the controller 56, and the photodetector Fine adjustment is performed to match the position of 14 with the position of the designed optical axis.
[0066]
In step S <b> 15, the adjustment device 41 performs fine adjustment to optimize the optical path length from the light source 12, that is, the light beam emission point to the adjustment optical disc 1. At this time, the controller 56 controls the objective lens driving unit 16 so that both focusing control and tracking control are turned on. The controller 56 controls the objective lens adjustment mechanism 42 that holds the objective lens 13, the light source adjustment mechanism 45 that holds the light source 12, and the light receiving unit detection mechanism 46 that holds the photodetector 14. Then, fine adjustment is performed to optimize the optical path length from the light beam emission point to the adjustment optical disc 1.
[0067]
Next, the adjustment device 41 performs skew adjustment. Here, the skew adjustment is performed so as to satisfy the tilt tolerance of the DVD because the tilt tolerance of the CD is smaller than the tilt tolerance of the DVD. Here, at least one of the adjustment recording optical disk 1 shown in FIG. 2, that is, the first recording area 8 of the first signal recording layer 5 and the second recording area 9 of the second signal recording layer 7 shown in FIG. When the optical discs with overlapping parts are loaded, the controller 56 switches the emitted light beam in step S16. That is, the output control unit 55 controls the light source 12 so as to emit a 635-650 nm light beam for DVD.
[0068]
Further, the adjustment optical disk 1 shown in FIG. 3, that is, the first recording area 8 of the first signal recording layer 5 and the second recording area 9 of the second signal recording layer 7 do not overlap the disk table 30. When the provided optical disk is mounted, the slide member 23 in which the optical pickup 11 is incorporated is fed in the radial direction of the adjustment optical disk 1 to a position where the second recording area 9 can be read. Thereafter, the controller 56 switches the emitted light beam in step S16. That is, the output control unit 55 controls the light source 12 so as to emit a 635-650 nm light beam for DVD.
[0069]
Then, the drive control unit 53 drives the drive motor 29 so that the linear velocity at the time of rotation of the adjustment optical disc 1 becomes 3.49 m / sec defined by the DVD standard, for example. In step S17, the controller 56 drives the objective lens adjustment mechanism 42 so that the jitter value generated by the signal detection unit 51 is minimized.
[0070]
In step S18, the adjusting device 41 confirms the optical characteristics during DVD playback. For example, the adjustment device 41 outputs the RF signal generated by the signal detection unit 51 to an optimum value based on the output from the photodetector 14 that has detected the return light beam reflected by the second signal recording layer 7. The controller 55 is controlled to check the adjustment of the output level of the light source 12 and the like.
[0071]
Next, the adjustment device 41 confirms the optical characteristics during CD reproduction. Here, at least one of the adjustment recording optical disk 1 shown in FIG. 2, that is, the first recording area 8 of the first signal recording layer 5 and the second recording area 9 of the second signal recording layer 7 shown in FIG. When the overlapping optical disks are loaded, the controller 56 switches the emitted light beam in step S19. That is, the output control unit 55 controls the light source 12 so as to emit a 780 nm light beam for CD.
[0072]
Further, the adjustment optical disk 1 shown in FIG. 3, that is, the first recording area 8 of the first signal recording layer 5 and the second recording area 9 of the second signal recording layer 7 do not overlap the disk table 30. When the provided optical disk is loaded, the slide member 23 in which the optical pickup 11 is incorporated is fed in the radial direction of the adjustment optical disk 1 to a position where the first recording area 8 can be read. Thereafter, in step S19, the controller 56 switches the emitted light beam. That is, the output control unit 55 controls the light source 12 so as to emit a 780 nm light beam for CD.
[0073]
Based on the control of the controller 56, the drive control unit 53 drives the drive motor 29 so that the linear velocity at the time of rotation of the adjustment optical disk 1 is 1.2 to 1.4 m / sec determined by the CD standard, for example. Drive.
[0074]
In step S20, the adjustment device 41 confirms the optical characteristics during DVD playback. For example, the adjustment device 41 outputs the RF signal generated by the signal detection unit 51 to an optimum value based on the output from the photodetector 14 that has detected the return light beam reflected by the second signal recording layer 7. The controller 55 is controlled to check the adjustment of the output level of the light source 12 and the like.
[0075]
Thereafter, the adjustment device 41 that has completed the optical adjustment of the optical pickup 11 performs, for example, an inspection of an error rate of the optical pickup 11 and the like. Thus, the optical pickup 11 whose optical characteristics have been adjusted is fixed to the slide member 23 with an adhesive.
[0076]
As described above, the adjustment of the optical pickup 11 uses the adjustment optical disc 1 provided with the first signal recording layer 5 in the physical format of CD and the second signal recording layer 7 in the physical format of DVD. Thus, the adjustment at the time of reproduction of the CD and the adjustment at the time of reproduction of the DVD can be smoothly performed without exchanging the adjustment optical disc as in the prior art.
[0077]
In this adjustment, since the concentric recording tracks are provided on both the first signal recording layer 5 and the second signal recording layer 7 of the adjustment optical disc 1, the objective lens 13 is gradually changed. Can be adjusted in a state where the optical axis of the objective lens 13 always coincides with the center of the light beam.
[0078]
In addition, since the adjustment optical disc 1 has data of the same modulation system recorded in the first signal recording layer 5 and the second signal recording layer 7, the demodulation unit 57 and the error correction processing unit of the adjustment device 41 are used. 58 etc. can be united.
[0079]
The adjustment optical disk 1 is used for adjustment of an optical pickup 11 capable of reproducing CDs and DVDs. As a modulation method of data to be recorded, a modulation method with a small number of bits after modulation, specifically, Since the 8-14 modulation which is the minimum in the CD is adopted instead of the 8-16 modulation adopted in the DVD, the processing at the time of demodulation can be lightened.
[0080]
Further, at least a part of the adjustment recording optical disk 1 shown in FIG. 2, that is, the first recording area 8 of the first signal recording layer 5 and the second recording area 9 of the second signal recording layer 7 overlap. When the optical disk is mounted, it is not necessary to send the optical pickup 11 only by switching the type of the light beam when switching between the adjustment at the time of reproducing the DVD and the adjustment at the time of reproducing the CD. Switching can be performed.
[0081]
Furthermore, the adjustment optical disk 1 shown in FIG. 3, that is, the first recording area 8 of the first signal recording layer 5 and the second recording area 9 of the second signal recording layer 7 are provided so as not to overlap. When the optical disk is mounted, data can be reliably read when the first recording area 8 of the first signal recording layer 5 is reproduced.
[0082]
It should be noted that the adjustment when reproducing the DVD in step S5 to step S9 and the adjustment when reproducing the CD in step S10 to step S15 are not limited to the example shown in FIG. The adjustment at the time may be performed after the adjustment at the time of reproducing the CD. Further, the step of checking the optical characteristics when reproducing the DVD in step S18 may be replaced with the step of checking the optical characteristics when reproducing the CD in step S20.
[0083]
Further, when the optical pickup 11 is constituted by a laser coupler, since components other than the objective lens 13 are integrated, at least step S5 to step S5 after adjusting coma aberration in steps S1 to S3. The adjustment performed in S15 may be omitted. That is, when the optical pickup 11 is composed of a laser coupler, it is only necessary to adjust the position of the objective lens.
[0084]
In the above example, the description is given by taking as an example the adjustment of the optical pickup 11 capable of reproducing both CD and DVD, but the present invention is not limited to this. That is, according to the type of the optical disc in which the optical pickup is used, the adjustment optical disc 1 is also formed with a signal recording layer in the physical format adopted by the optical disc, and the modulation method of the recorded data is also determined.
[0085]
【The invention's effect】
  The present inventionA first signal recording layer and a second signal recording layer;In each signal recording layer, recording of two types of optical disks using an optical disk for adjustment of an optical pickup in which data modulated by the same modulation method is recorded concentrically in different physical formats and / or Since the optical pickup that can be reproduced is adjusted, the optical pickup can be continuously performed without replacing the adjustment optical disk as in the prior art, and the optical pickup adjustment process can be speeded up.
Here, since the adjustment disc is provided so that the recording areas in which the data of each signal recording layer is recorded do not overlap each other, the data is surely read when reproducing one of the signal recording layers. be able to. Furthermore, the data modulated by the first modulation method is recorded on the first signal recording layer in the first physical format, and the data modulated by the first modulation method is recorded on the second signal recording layer. Since it is recorded in the second physical format and the first modulation method is a modulation method with a smaller number of bits after modulation than the second modulation method, the demodulator can be integrated into one and demodulated. Processing can be lightened.
[Brief description of the drawings]
FIG. 1 is a perspective view of an optical disk for adjusting an optical pickup to which the present invention is applied.
FIG. 2 is a cross-sectional view of an optical disk for adjustment provided so that a first recording area of a first signal recording layer and a second recording area of a second signal recording layer partially overlap each other.
FIG. 3 is a cross-sectional view of an optical disc for adjustment provided so that a first recording area of a first signal recording layer and a second recording area of a second signal recording layer do not partially overlap each other. .
FIG. 4 is a diagram illustrating a configuration of an optical pickup adjusting device.
FIG. 5 is a process diagram illustrating an optical pickup adjustment method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Optical disk for adjustment, 2 1st disk substrate, 3nd disk substrate, 4 adhesives, 1st signal recording layer, 7 2nd signal recording layer, 8 1st recording area, 9 2nd Recording area, 11 Optical pickup, 12 Light source, 13 Objective lens, 14 Photo detector, 15 Beam splitter, 16 Objective lens drive unit, 17 Lens holder, 18 Holder support member, 21 Base unit, 22 Base, 23 Slide member, 24 Feed mechanism, 25 disc rotation drive mechanism, 26 drive motor, 27 feed screw, 28 opening, 29 drive motor, 30 disc table, 41 adjustment device, 42 objective lens adjustment mechanism, 43 base holding mechanism, 44 slide member holding mechanism, 45 Light source adjustment mechanism, 46 Photodetector adjustment mechanism, 47 Detection mechanism, 48 CCD camera, 49 Coma aberration determination unit, 51 signal detection unit, 52 display unit, 53 drive control unit, 54 drive control unit, 55 output control unit, 56 controller, 57 demodulation unit, 58 error correction processing unit

Claims (14)

A first optical disk in which data modulated by the first modulation method is recorded in the first physical format and a second optical disk in which data modulated by the second modulation method is recorded in the second physical format. In an optical pickup adjusting device for reproduction,
A first signal recording layer and a second signal recording layer , wherein data modulated by the same modulation method is concentrically recorded in different physical formats in each signal recording layer; An optical disk for adjusting an optical pickup provided so that recording areas where data is recorded do not overlap each other is mounted, and a disk rotating mechanism for rotating the adjusting optical disk;
The light beam emitted from the light source is collected by the objective lens, and the return light beam reflected by the adjustment optical disc is detected by the photodetector, and the objective lens is moved along the optical axis direction of the objective lens and the optical axis. An optical pickup that is displaced by the objective lens driving unit in a direction orthogonal to the optical axis;
Moving means for moving the optical pickup in the radial direction of the adjustment optical disk;
Adjusting means for adjusting the relative position of the light source and the objective lens and the inclination of the optical axis of the objective lens ;
A demodulator that demodulates data recorded in the first and second signal recording layers detected by the photodetector of the optical pickup ,
In the adjustment optical disc, data modulated by the first modulation method is recorded in the first physical recording format in the first signal recording layer, and the first signal recording layer records the first signal in the first signal recording layer. Data modulated by the modulation method is recorded in the second physical format,
The first modulation scheme is a modulation scheme with a smaller number of bits after modulation than the second modulation scheme,
The demodulator demodulates the data recorded in the first and second signal recording layers modulated by the first modulation method;
When the optical pickup is moved to the first position by the moving means, the relative position between the light source and the objective lens is adjusted by irradiating one of the signal recording layers of the adjustment optical disc with the light beam. The light source and the objective by irradiating the other signal recording layer of the adjustment optical disc with the light beam when adjusted by the means and moved to the second position different from the first position by the moving means. An optical pickup adjusting device in which the relative position of the lens is adjusted by the adjusting means. The data recorded in the first and second signal recording layers is added with a first error correction code corresponding to the error correction method of the first optical disc,
  The optical pickup adjusting apparatus further includes an error correction processing unit that performs an error correction process on the data demodulated by the demodulation unit,
  2. The optical pickup adjusting apparatus according to claim 1, wherein the optical pickup adjusting apparatus inspects an error rate of the optical pickup. Furthermore, an imaging unit for imaging the light beam emitted from the light source is provided opposite to the optical pickup,
The imaging unit detects the light beam emitted from the optical pickup at a stage prior to performing adjustment by irradiating the signal recording layer of the optical disk for adjustment from the optical pickup, and based on the detection result the adjustment means, the optical pickup according to claim 1 or 2, wherein performing the adjustment for the coma aberration adjustment device.   The adjustment means irradiates the signal recording layer of the adjustment optical disc with a light beam from the optical pickup after adjusting the coma aberration, and based on the return light beam from the adjustment optical disc, the light source and the The optical pickup adjusting apparatus according to claim 3, wherein the adjustment relating to the relative position of the objective lens is performed.   Adjustment when the one signal recording layer is irradiated with a light beam is performed by adjusting the ± 1st order centering on the 0th order light among the 0th order light and the ± 1st order light emitted from the optical pickup to the adjustment optical disc. 5. The optical pickup adjusting device according to claim 4, wherein the adjusting is performed by rotating and adjusting the light source so that the phase difference of light becomes 180 degrees.   The adjusting means is configured to adjust the optical disk from the optical pickup in a state where the light beam emitted from the light source after the fine adjustment is finished follows the recording track formed on the signal recording layer of the adjusting optical disk. 6. The optical pickup adjusting device according to claim 5, wherein the optical axis inclination of the objective lens is adjusted based on the result of detecting the returning light beam from the adjusting optical disk.   The inclination of the optical axis of the objective lens is adjusted based on the jitter value of the detection output signal obtained by detecting the return light beam from the adjustment optical disk of the light beam irradiated from the optical pickup to the adjustment optical disk. The apparatus for adjusting an optical pickup according to claim 6. A first optical disk in which data modulated by the first modulation method is recorded in the first physical format and a second optical disk in which data modulated by the second modulation method is recorded in the second physical format. In the adjustment method of the optical pickup for reproduction,
The light beam emitted from the light source is collected by the objective lens, and the return light beam reflected by the adjustment optical disc is detected by the photodetector, and the objective lens is moved along the optical axis direction of the objective lens and the optical axis. Installing an optical pickup that is displaced by the objective lens drive unit in a direction orthogonal to the optical axis so that the light source can move relative to the objective lens;
A first signal recording layer and a second signal recording layer , wherein data modulated by the same modulation method is concentrically recorded in different physical formats in each signal recording layer; Mounting an optical disk for adjustment of an optical pickup provided so that recording areas where data is recorded do not overlap each other to the disk rotation mechanism;
Adjusting the relative position of the light source and the objective lens by moving the optical pickup to a first position by moving means, and irradiating one of the signal recording layers of the adjustment optical disc with the light beam;
The optical pickup is moved to a second position different from the first position by the moving means, and the other signal recording layer of the adjustment optical disc is irradiated with the light beam, whereby the relative relationship between the light source and the objective lens is increased. Adjusting the position and the tilt of the optical axis of the objective lens ;
Demodulating the data recorded in the first and second signal recording layers detected by the photodetector of the optical pickup ,
In the adjustment optical disc, data modulated by the first modulation method is recorded in the first physical recording format in the first signal recording layer, and the first signal recording layer records the first signal in the first signal recording layer. Data modulated by the modulation method is recorded in the second physical format,
The first modulation scheme is a modulation scheme with a smaller number of bits after modulation than the second modulation scheme,
A method of adjusting an optical pickup for demodulating data recorded in the first and second signal recording layers modulated by the first modulation method. The data recorded in the first and second signal recording layers is added with a first error correction code corresponding to the error correction method of the first optical disc,
  9. The method of adjusting an optical pickup according to claim 8, further comprising a step of performing an error correction process on the demodulated data and checking an error rate of the optical pickup. Further, the adjustment relating to coma aberration is performed by detecting the light beam emitted from the optical pickup before the adjustment is performed by irradiating the signal recording layer of the optical disk for adjustment from the optical pickup. 10. A method for adjusting an optical pickup according to 8 or 9 . After adjusting the coma aberration, the signal recording layer of the adjustment optical disc is irradiated with a light beam from the optical pickup, and the relative position of the light source and the objective lens is based on the return light beam from the adjustment optical disc. The method for adjusting an optical pickup according to claim 10, wherein the adjustment is performed. Adjustment when the one signal recording layer is irradiated with a light beam is performed by adjusting the ± 1st order centering on the 0th order light among the 0th order light and the ± 1st order light emitted from the optical pickup to the adjustment optical disc. 12. The method of adjusting an optical pickup according to claim 11, wherein the adjustment is performed by rotating the light source so that the phase difference of light is 180 degrees. The light beam emitted from the optical pickup to the adjustment optical disk in a state where the light beam emitted from the light source after following the adjustment is following the recording track formed on the signal recording layer of the adjustment optical disk 13. The method of adjusting an optical pickup according to claim 12, wherein the inclination of the optical axis of the objective lens is adjusted based on the result of detecting the returning light beam from the adjustment optical disk. The inclination of the optical axis of the objective lens is adjusted based on the jitter value of the detection output signal obtained by detecting the return light beam from the adjustment optical disk of the light beam irradiated from the optical pickup to the adjustment optical disk. The method of adjusting an optical pickup according to claim 13 .

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