KR100618989B1 - Error signal detection device for optical recorder - Google Patents

Abstract

Disclosed is an error signal detecting apparatus for an optical recording / reproducing apparatus, comprising a photodetector for detecting an information signal for receiving light reflected / diffracted on a recording medium and a circuit unit for calculating an error signal of the photodetector to detect an error signal. In the disclosed error signal detecting apparatus for an optical recording / reproducing apparatus, a photodetector includes four light receiving regions whose row direction division lines and column direction division lines are arranged in a counterclockwise direction substantially parallel to the radial direction and the track tangential direction of the recording medium ( A1, A2 (B1, B2) (C1, C2) (D1, D2) are divided by the inner partition plate A2 (B2) (C2) (D2) and the outer division by a dividing boundary line approximately parallel to the track tangential direction, respectively. Eight split plates (A1) (A2) (B1) (B2) divided into two plates (A1) (B1) (C1) (D1) to photoelectrically convert incident light independently and form a 2x4 matrix (C1) (C2) (D1) (D2), and the circuit section compares the phases between the detection signals of the inner and / or outer dividers located in the same row, respectively, and then compares the phases from the phase comparison signal. Characterized in that it is provided to obtain a slope error signal.

By adopting such an error signal detecting device for an optical recording / reproducing apparatus, an inclination error signal with high accuracy and precision can be detected, and an inclination error signal can be detected sensitively to the relative inclination between the recording medium and the objective lens. Further, the error signal detection apparatus for the optical recording / reproducing apparatus can be used for tracking error signal detection.

Description

Error signal detecting apparatus for optical recording / reproducing device

1 is a view schematically showing an example of a general optical pickup;

2 is a schematic view showing a conventional inclination error signal detecting apparatus;

3 is a perspective view showing light reflected / diffracted in a general high density recording medium;

4 is a configuration diagram schematically showing an error signal detection apparatus for an optical recording / reproducing apparatus according to an embodiment of the present invention;

5 is a graph showing a signal output from the circuit portion of FIG. 4 when the tracking servo is not operated;

6 is a graph showing a signal output from the circuit part of FIG. 4 when the tracking servo is operated;

7 to 16 are each a schematic view showing an error signal detecting apparatus for an optical recording / reproducing apparatus according to another embodiment of the present invention;

17 and 18 are schematic diagrams respectively showing an error signal detection apparatus for an optical recording / reproducing apparatus according to still another embodiment of the present invention;

19 and 20 show another embodiment of the photodetectors of FIGS. 17 and 18,

FIG. 21 is a view schematically showing a photodetector having a 16-division structure which may be commonly applied to FIGS. 17 to 20;

22 shows yet another embodiment of the photodetectors of FIGS. 17 and 18.

<Description of the symbols for the main parts of the drawings>

30,600,700 ... Photodetectors 30a, 30b, 30c, 30d ...

50,150,250,350.450,650,750 ... circuit 51,53,159,751,753 ... phase comparators

59,455 ... Adder 60,255 ... Low Pass Filter

70 Envelope or signal center detector 151 Delay element

155,451 ... gain regulator 257,759 ... differential

453 ... Differential Amplifier

The present invention relates to an error signal detection apparatus for an optical recording / reproducing apparatus, and more particularly, to detect a relative tilt error signal between an objective lens and a recording medium by using a main beam for recording / reproducing an information signal of a recording medium. The present invention relates to an error signal detection device for an optical recording / reproducing apparatus.

In general, an optical pickup records / reproduces an information signal while moving in a radial direction of a recording medium such as a rotating disk mounted on a turntable, and such recording is performed when the rotating disk is tilted due to bending of the disk itself or a disc loading error. / Deterioration occurs in the playback signal.

In particular, in the case of an optical pickup apparatus employing a light source that emits shorter wavelength light and an objective lens having a larger numerical aperture to increase recording density, since optical aberration is proportional to λ / (NA) ^{^ 3} , Due to the inclination of the disk, coma aberration is greatly generated, and the deterioration of the recording / reproducing signal becomes more serious.

In order to prevent such deterioration of the recording / reproducing signal by detecting the inclination amount of the disc and correcting the inclination, the detection signal of the photodetector 9 conventionally employed in the general optical pickup as shown in FIG. Has been proposed to detect the relative inclination between the disk 10 and the objective lens 7 as shown in FIG.

1 is a view showing an example of an optical configuration of a general optical pickup. Referring to the drawings, the laser light output from the information signal recording and reproducing light source 1 passes through the beam splitter 5 and is incident on the objective lens 7. The objective lens 7 focuses the light incident from the light source 1 to form a light spot on the recording surface of the disk 10. Light reflected from the recording surface of the disk 10 passes through the objective lens 7 and is reflected by the beam splitter 5 toward the photodetector 9. Here, reference numeral 8 is a photodetector lens for focusing the light reflected by the beam splitter 5 and incident to the photodetector 9.

The photodetector 9 is composed of four split plates (A, B, C, D of FIG. 2) for receiving incident light and photoelectrically converting them independently. Accordingly, the information signal and the error signal are detected by properly summing and / or differentially detecting the detection signals of the partition plates A, B, C, and D.

Referring to Fig. 2, the conventional inclination error signal detecting apparatus is divided into a photodetector 9 for information signal recording and reproduction made up of four division plates A, B, C, and D, and a partition plate A and D. Radial push differentially between the first and second adders 11 and 13 for summing the detection signals of the plates B and C, and the signals input from the first and second adders 11 and 13, respectively. It consists of a differential 15 for outputting a full signal.

At this time, the radial push-pull signal output from the differential 15 corresponds to a slope error signal, and the radial push-pull signal is also used as a tracking error signal.

The inclination error signal output from the conventional inclination error signal detection device as described above is input to the device for adjusting the relative inclination between the objective lens 7 and the disk 10 and used to correct the inclination error.

The conventional inclination error signal detection apparatus as described above has the advantage that the configuration is simple. However, since the inclination error signal is detected by differentially detecting the detection signals of the two split plates with respect to the central axis parallel to the track tangential direction, Even when the lens shift occurs or the distance between the objective lens and the disc is out of the on focus position, the tilt error signal is sensitively changed, so that it is difficult to detect the exact tilt error degree.

On the other hand, the light reflected by the light spot on the disc for recording and reproduction is then diffracted in the 0th order and ± 1th order by a mark such as a pit P formed on the disc 20 track, as shown in FIG. . Therefore, the light received by the photodetector 1 is one in which the 0th order diffracted light and the ± 1st order diffracted light overlap substantially in the radial direction. 3 shows a portion of a narrow track high density disk, for example, a ROM type disk, in which the 0th order diffraction light and the ± 1st order diffraction light overlap each other, but the + 1st order diffraction light and the -1st order diffraction light It does not overlap.

At this time, the detection signal of the portion where the 0th-order diffraction light and the + 1st-order diffraction light overlap and the portion where the 0th-order diffraction light and the -first-order diffraction light overlap and the detection signal of only the 0th-order diffracted light exhibit different characteristics. Therefore, as in the conventional inclination error signal detection apparatus described with reference to FIG. 2, the incident light is simply received by four division plates A, B, C, and D, and the inclination error signal, that is, the radial push-pull signal In the case of detecting C, the characteristics are erased from each other, so that the accuracy of the slope error signal is very low.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described points, and each independently photoelectrically converts overlapping portions of zero-order diffraction light, ± first-order diffraction light, and portions only of zero-order diffraction light having different characteristics, SUMMARY OF THE INVENTION An object of the present invention is to provide an error signal detection apparatus for an optical recording / reproducing apparatus having a structure capable of detecting an inclined error signal with high precision.

In order to achieve the above object, the present invention provides an information signal detection photodetector for receiving light reflected / diffracted in the recording medium; And a circuit unit for detecting an error signal by calculating a detection signal of the photodetector, wherein the photodetector includes a row division boundary line and a column division boundary line of the recording medium. 4 light-receiving areas A1, A2, B1, B2, C1, C2, D1, D2, which are approximately parallel to the radial and track tangential directions of the beams, and are arranged substantially parallel to the track tangential direction, respectively. The dividing boundary divides the light into the inner dividing plate A2 (B2) (C2) (D2) and the outer dividing plate A1 (B1) (C1) (D1), and independently converts incident light into photoelectric conversion. Eight partition plates A1 (A2) (B1) (B2) (C1) (C2) (D1) (D2) forming a 2x4 matrix arrangement, wherein the circuit portion is located inside and And / or compare phases of the detection signals of the outer partitions with each other, and then obtain a slope error signal from the phase comparison signal. It is characterized in that it is prepared to.

According to an aspect of the present invention, the circuit unit includes: a first phase comparator configured to compare phases of detection signals of a pair of inner partition plates positioned in a first row and to output a phase comparison signal; A second phase comparator for comparing the phases of the detection signals of the remaining pair of inner division plates located in the second row with each other and outputting a phase comparison signal; And an adder for summing the phase comparison signals from the first and second phase comparators.

According to another feature of the invention, the circuit unit comprises: a first phase comparator for comparing the phases of the detection signals of the pair of outer division plates located in the first row and outputting the phase comparison signal; A second phase comparator for comparing the phases of the detection signals of the remaining pair of outer division plates located in the second row with each other and outputting a phase comparison signal; And an adder for summing the phase comparison signals from the first and second phase comparators.

According to another feature of the present invention, the circuit unit outputs the phase comparison signal by comparing the phase between the detection signals of the outer partition plates positioned in the first row and the phase between the detection signals of the inner partition plates, respectively. First and second phase comparators; Third and fourth phase comparators for comparing the phase between the detection signals of the outer partition plates positioned in the second row and the phase between the detection signals of the inner partition plates, respectively, and outputting a phase comparison signal; A first adder for adding a phase comparison signal based on detection signals of the outer dividers from the first and third phase comparators and outputting a first phase sum signal; A second adder for adding a phase comparison signal based on detection signals of inner dividers from the second and fourth phase comparators and outputting a second phase sum signal; And a differential unit for outputting a slope error signal by differentiating the first and second phase sum signals inputted from the first and second adders.

Here, the circuit unit may further include a third adder for outputting a tracking error signal by summing the first and second phase sum signals inputted from the first and second adders.

The circuit unit may further correct the amplitude difference between the first and second phase sum signals output from the first and second adders according to the division ratios of the inner and outer dividers of the photodetector. Or a gain adjuster for amplifying a phase sum signal by a predetermined gain at the output terminal of the second adder by the detection signals of the inner and outer partition plates.

On the other hand, in order to achieve the above object, the present invention, a photodetector for receiving light reflected / diffracted in the recording medium; And a circuit unit for detecting an error signal by calculating a detection signal of the photodetector, wherein the photodetector includes a row division boundary line and a column division boundary line of the recording medium. The four light-receiving areas A1, A2, B1, B2, C1, C2, D1, D2, which are approximately parallel to the radial and track tangential directions of the beams, are arranged substantially parallel to the track tangential direction, respectively. The dividing boundary divides the light into the inner dividing plate A2 (B2) (C2) (D2) and its outer dividing plate (A1) (B1) (C1) (D1), thereby independently photoelectric conversion of the incident light, Eight partition plates A1 (A2) (B1) (B2) (C1) (C2) (D1) (D2) forming a 2x4 matrix arrangement, wherein the circuit portion is located in one diagonal direction And / or amplify the detection signal of the outer divider to a predetermined gain, and located inside and / or in a diagonal direction different from the amplified signal. The phase comparison with the detection signal of the outer side divider is compared, and the inclination error signal can be obtained from the phase comparison signal.

According to one aspect of the invention, the circuit unit, a gain adjuster for amplifying the sum signal of the detection signal of the inner or outer partition plate located in one diagonal direction to a predetermined gain; And a phase comparator configured to compare the phases between the sum signal of the detection signals of the inner or outer dividers positioned in different diagonal directions and the output signal of the gain adjuster.

The circuit unit may further include a delay unit configured to time-delay a detection signal of an inner or outer partition plate located in one diagonal direction, to prevent phase degradation of an error signal due to a pit depth difference of a recording medium. It is preferable.

According to another feature of the invention, the circuit unit, the first signal and the second to amplify the sum signal of the detection signal of the inner partition plates located in one diagonal direction and the sum signal of the detection signal of the outer partition plates to a predetermined gain, respectively A gain regulator; The phases between the sum signal of the detection signals of the inner dividers positioned in different diagonal directions, the output signal of the first gain regulator, the sum signal of the detection signals of the outer dividers, and the output signal of the second gain regulator are compared with each other. Outputting first and second phase comparators; And a differential to output a gradient error signal by differentially inputting signals from the first and second phase comparators.

The circuit unit may further include a third adder configured to add a signal input from the first and second phase comparators to output a tracking error signal.

The circuit unit may correct the amplitude difference of the phase comparison signal output from the first and second phase comparators according to the division ratios of the inner and outer partition plates of the photodetector. It is preferable that the output terminal of the comparator further comprises a third gain regulator for amplifying the phase comparison signal output therefrom with a predetermined gain.

On the other hand, in order to achieve the above object, the present invention provides a photodetector for detecting an information signal for receiving the light reflected / diffracted on the recording medium; And a circuit unit for detecting an error signal by calculating a detection signal of the photodetector, wherein the photodetector is configured to detect a partial region of light reflected / diffracted by the recording medium and incident. First to fourth split plates arranged so that their row and column directions form a 2x2 matrix approximately parallel to the radial and track tangential directions of the recording medium, so as to selectively receive and photoelectrically convert incident light independently; (A) (B) (C) (D), each of which comprises at least four partition plates, wherein the circuit section compares phases between detection signals of the partition plates located in the same row or column, respectively, and then Characterized in that the inclination error signal can be detected from the phase comparison signal.

According to one feature of the invention, the first to fourth split plates (A) (B) (C) (D) of the photodetector are spaced apart from each other by G _x1 and G _{y1 in} the radial and track directions, respectively. Placed.

According to another feature of the invention, the first to fourth divided plates (A) (B) (C) (D) of the photodetector, the predetermined interval (G _x1 ) in the radial direction or a predetermined interval (in the track direction ( G _y1 ) are spaced apart from each other.

Here, the separation distance between the first to fourth split plates A, B, C, and D along the radial direction and / or the track direction is approximately 10% to 80% of the zero-order diffraction beam diameter. It is preferable to receive the zeroth order diffraction beam portion of the range or to receive the external portion thereof.

According to another feature of the invention, the first to fourth split plates (A) (B) (C) (D) of the photodetector receive the center region of the zeroth order diffracted beam reflected / diffracted on the recording medium. Are placed in close proximity to one another so that they

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 is a view schematically showing the configuration of an error signal detection apparatus for an optical recording / reproducing apparatus according to an embodiment of the present invention.

Referring to the drawings, an error signal detecting apparatus according to an embodiment of the present invention includes a photodetector 30 and a photodetector 30 for receiving light reflected / diffracted from a recording medium such as a disk (20 in FIG. 3). And a circuit portion 50 for calculating an error signal by calculating a detection signal. Here, the photodetector 30 receives the light reflected and incident from the recording medium, and the detection signal is a relative inclination error signal between the objective lens (7 of FIG. 1) and the recording medium, a tracking error signal, and the recording medium. It is used to detect playback signals and the like. That is, the photodetector 30 is a photodetector used for detecting an information signal in the optical pickup apparatus.

The photodetector 30 includes four light-receiving regions in which the row boundary dividing line and the column division dividing line are substantially parallel to the radial direction and the track tangential direction of the recording medium, and are arranged counterclockwise in a 2 × 2 matrix arrangement. 30a: A1, A2 (30b: B1, B2) (30c: C1, C2) (30d: D1, D2). The light receiving regions 30a, 30b, 30c, and 30d respectively correspond to the inner partition plates A2, B2, C2, and D2 along the row direction, that is, the radial direction. It is divided into two by (B1) (C1) (D1).

Therefore, the photodetector 30 is arranged in two rows and four columns of 2 × 4 matrix, each of the eight divided plates A1, A2, B1, B2, C1, C2, D1 independently photoelectric conversion. (D2), and the arrangement order of the outer partitions A1 (B1) (C1) (D1) and the inner partition plates (A2) (B2) (C2) (D2) respectively follows the counterclockwise direction. .

On the other hand, the error signal detection apparatus according to this embodiment and the other embodiments of the present invention to be described later, as described with reference to Figure 3, reflected from the recording medium and in the 0th order and ± 1st order diffracted light along the radial direction When the diffracted light is received by the photodetector, the 0th-order diffraction light, the + 1st-order diffraction light, the 0th-order diffraction light, and the -first-order diffraction light overlap some portions thereof, and the ± first-order diffraction light does not overlap each other. It is adapted to.

That is, the inner dividing plates A2, B2, C2, and D2 may include portions in which the 0th-order diffraction light and the + 1st-order diffraction light overlap and the portions in which the 0th-order diffraction light and the -first-order diffraction light overlap. It is provided so as not to receive at all or to receive only part of it. Therefore, the inner partition plates A2, B2, C2, and D2 have a narrow width in the radial direction and a long form in the tangential direction.

Of course, the total width along the radial direction of the inner partition plates A2, B2, C2, and D2 is determined by the track pitch of the recording medium, the pit length, the numerical aperture of the objective lens (7 in FIG. 1), In consideration of the emission light wavelength and the like, it is provided with a suitable size within a range for receiving approximately 10% to 80% of the zero-order diffracted light.

Here, the total width along the radial direction of the inner partitions A2, B2, C2, and D2 is the overlapping portion of the zeroth order diffraction light and the + 1st order diffraction light or the zeroth order diffraction light and the -first order diffraction light. It is more preferable that it is the maximum value which does not receive the overlapping part of light.

Therefore, in the signals a2, b2, c2 and d2 respectively detected by the inner dividing plates A2, B2, C2 and D2, the characteristics of only the 0th order diffracted light are sufficiently alive and the outer dividing plate ( In the signals a1, b1, c1, and d1 respectively detected by A1, B1, C1, and D1, the characteristics of the overlapped portions of the 0th order and ± 1st order diffracted light are sufficiently alive.

That is, for example, when an optical spot is formed in the track center of the recording medium, the detection signals a1 (b1) (c1) of the outer partition plates A1 (B1) (C1) (D1) according to the radial tilt error. ) and the phase relationship between the detection signals a2 (b2) (c2) and d2 of the inner partition plates A2, B2, C2 and D2 are as follows. When the radial slope is positive, the phase of the detection signal a1 is slower than the phase of the detection signal b1, the phase of the detection signal c1 is slower than the phase of the detection signal d1, and the radial slope is negative. Is the opposite.

In addition, when the radial slope is positive, the phase of the detection signal a2 is faster than the detection signal b2, the phase of the detection signal c2 is faster than the phase of the detection signal d2, and the radial slope is negative. Is the opposite.

In the present embodiment, the circuit unit 50 compares phases between detection signals of the inner partition plates A2, B2, C2, and D2 located on the same row, that is, on the same line in the tangential direction. Then, the inclination error signal is obtained from the phase comparison signal.

For example, as shown in FIG. 4, the circuit unit 50 compares phases between detection signals of the inner partition plates A2, B2, C2, and D2 located in the same row, respectively. First and second phase comparators 51 and 53 for outputting the phase comparison signal, and an adder 59 for summing the phase comparison signals from the first and second phase comparators 51 and 53. It is configured by.

The detection signals of the pair of inner partition plates A2 and B2 positioned in the first row are input to the first phase comparator 51 so that the phases are compared with each other. The second phase comparator 53 receives the detection signals of the pair of inner partition plates A2 and B2 positioned in the second row and compares the phases with each other.

Therefore, the error signal output from the adder 59 is a pair of inner partition plates A2 on the same row input from the first and second phase comparators 51 and 53, that is, on the same line in the tangential direction. The phase comparison signal between the detection signals of (B2) and the phase comparison signal between the detection signals of the remaining pair of inner partition plates A2 and B2 are summed.

5 is a graph showing a signal output from the adder 59 when the tracking servo of the optical recording / reproducing apparatus is not operated.

Referring to FIG. 5, since the tracking control is not performed, when a relative inclination error between the objective lens and the recording medium does not occur, the adder 59 includes a signal including only the tracking error component as shown in FIG. Is output.

In addition, when a relative inclination error between the objective lens and the recording medium occurs, the adder 59 outputs a signal including not only the tracking error component but also the inclination error component as shown in FIG. Here, in FIG. 5B, a high frequency component represents a tracking error signal and a low frequency component represents a slope error signal.

As described above, when a tracking error and / or a slope error occurs, the signal output from the adder 59 includes a tracking error signal component and / or a slope error signal component, so that the output signal of the adder 59 Not only can be used as a slope error signal, it can also be used as a tracking error signal if necessary.

FIG. 6 is a graph showing a signal output from the adder 59 when the tracking servo is operated so that the light spot irradiated to the recording medium follows the on track position.

Referring to FIG. 6, since the tracking servo is operated, in the case where the relative inclination error between the objective lens and the recording medium does not occur, the adder 59 inclines as shown in FIG. A signal is output that contains little error and tracking error components.

In addition, when a relative inclination error between the objective lens and the recording medium occurs, the adder 59 hardly contains a tracking error component because tracking servo is operated as shown in Fig. 6B. The signal including only the slope error component is output.

On the other hand, in the conventional optical recording / reproducing apparatus, the tracking servo continues to operate in the recording / reproducing mode.

Therefore, when the error signal detecting apparatus according to the embodiment of the present invention as shown in FIG. 4 is employed in the optical recording / reproducing apparatus, as shown with reference to FIGS. 5 and 6, the adder of the circuit unit 50 ( Since the inclination error signal is output from 59, the output signal of this adder 59 can be used to control the relative inclination between the objective lens and the recording medium. Of course, the error signal detection apparatus of FIG. 4 may be used for tracking error signal detection, if necessary.

On the other hand, the error signal detection apparatus shown in Figure 4 is suitable for obtaining the slope error signal when the tracking servo is operating, to obtain the slope error signal regardless of whether the tracking servo operation, as shown in Figure 7, The low pass filter 60 which outputs the input signal by low pass filtering may be further provided at the output terminal of the adder 59 of the circuit part 50 of 4.

In this case, since the tracking error signal component, which is a relatively high frequency component, of the signals output from the adder 59 does not pass through the low pass filter 60, the slope error signal component, which is a relatively low frequency component, in the circuit unit 50 Only the output is passed through the low pass filter 60.

Alternatively, to obtain the inclination error signal even when the tracking servo is inactive, as shown in FIG. 8, the envelope of the signal output from the circuit section 50 at the output of the adder 59 of the circuit section of FIG. 4, or What is necessary is just to provide the detector 70 which detects the change of the center value of the signal output from the said circuit part 50.

For example, when the detector 70 is provided with an envelope detector, the envelope detector includes an envelope of a signal as shown in FIG. 5 (b) or FIG. 6 (b) output from the adder 59. In other words, a relatively low frequency slope error signal is detected. Accordingly, the envelope detector outputs a signal as shown in FIGS. 6A and 6B according to whether or not a tilt error occurs.

When the detector 70 includes a signal center value detector, the detector detects and outputs the center value of the tracking error signal component. In this case, the change in the center value of the tracking error component corresponds to the gradient error signal component and is substantially the same as the envelope signal.

FIG. 9 is a view schematically showing an error signal detecting apparatus for an optical recording / reproducing apparatus according to another embodiment of the present invention, wherein the detection signals of the inner partition plates A2 and C2 where the circuit unit 150 is located in one diagonal direction are shown in FIG. (a2) (c2) is amplified by a predetermined gain k, and the amplification signal is compared with the phase comparison between the detection signals b2 and d2 of the inner partition plates B2 and D2 positioned in different diagonal directions. This feature is characterized in that the error signal is detected from the phase comparison signal.

That is, the circuit unit 150 amplifies the sum signal a2 + c2 of the detection signals a2 and c2 of the inner dividing plates A2 and C2 positioned in one diagonal direction to a predetermined gain k. The summation signal b2 + d2 of the regulator 155, the detection signals b2 and d2 of the inner partition plates B2 and D2 positioned in different diagonal directions, and the output signal k of the gain regulator 155; and a phase comparator 159 for detecting an error signal by comparing the phases between a2 + c2). At this time, the gain k is a constant value other than zero.

The error signal detection apparatus as described above sums up the detection signals of the inner partition plates in the diagonal direction similarly to the general DPD method. However, only approximately 0th order diffracted light portion of the light incident on the inner dividing plates A2, B2, C2, and D2 is received, and the detection signal of the inner dividing plates located in one diagonal direction is also received. After amplifying the sum signal with a predetermined gain, the amplified signal is compared with the sum signal of the sum signal of the detection signals of the inner dividers located in different diagonal directions, so that the offset of the slope error signal component is corrected.

Meanwhile, as shown in FIG. 10, the circuit unit 150 of FIG. 9 has a delay element 151 between the output terminal of the inner partition plates A2 and C2 and the gain adjuster 155 positioned in one diagonal direction. It may be further provided.

In this case, the sum signal of the detection signals a2 and c2 of the inner dividing plates A2 and C2 is converted into a time delayed signal via the delay element 151, and the time delayed signal is converted into a gain adjuster ( 155 is input and amplified, and then phases are compared with the sum signal of the detection signals b2 and d2 of the inner dividing plates B2 and D2 positioned in different diagonal directions.

As shown in FIG. 10, when the sum signal of the detection signals of the inner partitions positioned in one diagonal direction is delayed and an error signal is detected therefrom, the detection signals of the two inner partitions positioned in each diagonal direction are compared in phase comparison. There is an advantage that can prevent phase degradation due to signal distortion that can be caused by summing.

In particular, due to the phase comparison offset generated between the sum signals in the diagonal direction due to the actual deviation of the pit depth present in each signal recording medium, the offset of the error signal that may be caused when the objective lens (not shown) is shifted is corrected. As a result, more accurate error signals can be detected.

That is, the circuit unit 150 of FIG. 10 according to the present invention first sums up detection signals of the partition plates on the same diagonal line, but detects an error signal through the time delay and amplification process as described above. Even when an error occurs in the pit depth, the problem of phase degradation due to signal distortion caused by the pit depth change is greatly improved. Therefore, even when a lens shift occurs, it is possible to detect an error signal in which the offset is greatly reduced.

Meanwhile, the error signal detection apparatus of FIGS. 9 and 10 according to the present invention as described above outputs an inclination error signal during the operation of the tracking servo, as described with reference to FIG. Can be used for tracking error signal detection. In addition, as described with reference to FIGS. 7 and 8, if a low pass filter 60, an envelope, or a signal center value detector 70 is further provided, the inclination error signal may be output regardless of the tracking servo operation. have.

As described above, the error signal detecting apparatus according to the present invention described with reference to FIGS. 4 and 7 to 10 includes the inner partition plates A2, B2, C2, and D2 of which the 0th order diffracted light is received. Since the error signal is detected using the detection signal of?, An inclined error signal with high precision can be detected. This is because the phase characteristic of the zeroth order diffracted light of the zeroth order and ± first order diffracted light reflected / diffracted on the recording medium is sensitively changed to the relative tilt of the recording medium with respect to the objective lens.

In addition, the error signal detection apparatus according to the present invention as described with reference to FIGS. 4, 7 and 8 obtains a phase comparison signal between the detection signals of the inner partition plates arranged along the radial direction, respectively, and then the phase Since the error signal is detected by summing the comparison signals, the tilt error signal does not fluctuate sensitively even when the objective lens shift occurs or the distance between the objective lens and the disc is out of the on-focus position, so that the correct tilt error accuracy is obtained. Can be detected.

FIG. 11 is a view schematically showing an error signal detecting apparatus for an optical recording / reproducing apparatus according to another embodiment of the present invention, and has the same configuration as the error signal detecting apparatus according to the embodiment of the present invention described with reference to FIG. 4. There is a difference in that the detection signals a1 (b1) (c1) and (d1) of the outer partitions A1, B1, C1, and D1 are input to the circuit unit 250.

That is, the circuit unit 250 is provided to the first phase comparator 51 and the second row to compare the phases of the detection signals a1 and b1 of the outer partition plates A1 and B1 positioned in the first row. Output from the second phase comparator 53 and the first and second phase comparators 51 and 53 for comparing the phases of the detection signals c1 and d1 of the located outer dividers C1 and D1. And an adder 59 for summing up the phase comparison signals.

In the circuit unit 250 having the above configuration, an error signal including an inclination error and / or a tracking error component is emitted.

Thus, as described with reference to FIG. 4, the circuit unit 250 outputs an inclination error signal while the tracking servo is operating. In addition, the detection signal of the circuit unit 250 may be used for detecting a tracking error signal if a tilt error does not occur. In addition, when the circuit unit 250 further includes a low pass filter 60, an envelope, or a signal center detector 70 as described with reference to FIGS. 7 and 8, an inclination error regardless of whether tracking servo operation is performed or not. The signal can be detected.

Meanwhile, as illustrated in FIG. 12, the circuit unit 250 includes a low pass filter 255 provided at an output terminal of the adder 59, a signal branched at an output terminal of the adder 59, and the low pass filter ( A differential 257 may be further provided to differential the signal output from the signal 255. In this case, only a relatively low frequency gradient error component of the signal output from the adder 59 passes through the low pass filter 255, and a relatively high frequency tracking error component does not pass through the low pass filter 255. can not do it. Therefore, when the differential signal 257 differentials the signal including the gradient error component and the tracking error component output from the adder 59 and the gradient error component signal output from the low pass filter 255, the gradient error component is removed. The differential error signal 257 outputs a tracking error signal.

Here, the low pass filter 255 and the differential 257 may be employed at the output terminal of the error signal detecting apparatus of FIGS. 4, 9, and 10. In this case, the error signal detection device becomes a tracking error signal detection device.

13 and 14 illustrate an error signal detecting apparatus according to still another exemplary embodiment of the present invention using detection signals of the outer partitions A1, B1, C1, and D1. 13 and 14, except that the detection signals of the outer partitions A1, B1, C1, and D1 are input to the circuit unit 350. 9 and 10 have substantially the same configuration as the error signal detection apparatus shown in FIG.

Signals output from the error signal detection apparatuses shown in FIGS. 13 and 14 can be used for inclination error signal detection while the tracking servo is operating, and the circuit unit 350 as shown in FIGS. If the low pass filter 60 or the envelope or the signal center value detector 70 is further provided, the inclination error signal can be output from the circuit unit 350 regardless of whether or not the tracking servo is operated.

In addition, if the circuit unit 350 further includes a low pass filter 255 and a differential 257 as shown in Fig. 12, the output signal can be used for tracking control.

In the error signal detecting apparatus for an optical recording / reproducing apparatus according to the present invention described with reference to FIGS. 4, 9, 10, 11, 13, and 14, the tracking servo operation and the relative inclination between the recording medium and the objective lens are described. An error signal is output that includes a tracking error and / or a slope error component in relation to the error.

Therefore, when the tilt error detection circuit portion and the tracking error detection circuit portion are configured in pairs using at least one of the circuit portions according to the present invention, the tilt error signal and the tracking error signal can be detected simultaneously.

Further, if the low pass filter 60 of FIG. 7 or the detector 70 of FIG. 8 is further provided at the output end of the circuit unit shown in FIGS. 4, 9, 10, 11, 13, and 14, unnecessary signals are required. It is possible to detect a more accurate tilt error signal from which the component has been removed. In addition, when the output terminal of the circuit unit further includes a low pass filter 255 and a differential 257 as shown in FIG. 12, unnecessary signal components are removed to detect a more accurate tracking error signal.

15 is a view schematically showing an error signal detection apparatus according to another embodiment of the present invention. In this embodiment, the circuit unit 450 detects the detection signals a1 (a2) (A1) (A2) (A1) (A2) (B1) (B2) (C1) (C2) (D1) and (D2). It is characterized in that an error signal is detected from a signal comparing phases between the partition plates located in the same row using all of b1) (b2) (c1) (c2) (d1) (d2). .

That is, the circuit unit 450 is a first circuit for obtaining an error signal S1 from the detection signals a1, b1, c1, and d1 of the outer partitions A1, B1, C1, and D1. The second circuit portion (2) for obtaining the error signal S2 from the portion 250 and the detection signals a2, b2, c2 and d2 of the inner dividers A2, B2, C2 and D2. 50) and a differential amplifier 453 which detects the slope error signal by differentially differenting the error signal S1 and the error signal S2. In addition, it is preferable to further include an adder 455 that adds the error signal S1 and the error signal S2 to detect a tracking error signal.

The error signal S1 is the same as the signal output from the error signal detecting apparatus of FIG. 11, and the first circuit portion 250 is the same as that of FIG. 11 between the outer partition plates located along the radial direction. Each phase comparison signal is obtained, and then the phase comparison signals are summed. The error signal S2 is the same as the signal output from the error signal detecting apparatus of FIG. 4, and the circuit portion 50 is the phase comparison between the inner partition plates positioned along the radial direction as in FIG. 4. Each signal is obtained, and then the phase comparison signals are summed. Here, since the circuit portions 50 and 250 have the same configuration as the circuit portions of FIGS. 4 and 11, they are denoted by the same reference numerals, and detailed description thereof will be omitted.

At this time, the error signal S1 using the detection signal of the outer partitions A1, B1, C1 and D1 and the detection signal of the inner partitions A2, B2, C2 and D2 are used. The error signals S2 have substantially opposite polarities, and the envelope phases, that is, the phases of the gradient error signal components are shifted by approximately 180 degrees. Of course, the error signal S1 and the tracking error signal component included in the error signal S2 have approximately the same phase.

Therefore, when the error signals S1 and S2 are inputted to the differential amplifier 455 for differential, the tracking error signal components included in the error signals S1 and S2 are differentially erased from each other, and the error signal ( The magnitudes of the slope error signal components whose polarities included in S1) and S2 are opposite to each other become approximately the magnitude corresponding to the sum of their absolute values.

In addition, when the error signals S1 and S2 are inputted to the adders 59 and 459, the slope error signal components included in the error signals S1 and S2 are erased from each other, and the tracking error signal components are eliminated. Only the sum is output.

Therefore, the differential amplifier 45 detects a slope error signal with a larger maximum amplitude, and the adder 59 detects a tracking error signal with a larger maximum amplitude. Thus, when the error signal detection apparatus according to the present embodiment is used, A more accurate tilt error signal and / or tracking error signal can be detected.

On the other hand, the error signal detection apparatus according to the present embodiment, the inner and outer partition plates of the photodetector 30 (A1) (A2) (B1) (B2) (C1) (C2) (D1) (D2) A gain adjuster 451 for adjusting the gain of at least one of the error signal S1 and the error signal S2 is further added to correct an amplitude difference between the error signal S1 and the error signal S2 according to the division ratio. It is preferable to provide.

For example, the gain adjuster 451 is provided at an output terminal of the adders 59 and 59 to which the error signal S2 is output, and amplifies the error signal S2 to a predetermined gain k1.

In this case, the amplitude of the error signal S2 via the gain adjuster 451 and the amplitude of the error signal S1 not passing through the gain adjuster 451 can be made the same, and the differential amplifier 453 has a tracking error signal. An inclination error signal in which the component is completely removed is detected, and a tracking error signal in which the inclination error signal component is completely removed in the adder 455 is detected.

Therefore, the error signal detection apparatus according to the present invention as described above further includes a gain adjuster 451, thereby further increasing the accuracy of the slope error signal and the tracking error signal.

16 is a view schematically showing an error signal detection apparatus according to another embodiment of the present invention. In this embodiment, the circuit unit 450 detects the detection signals a1 (a2) (A1) (A2) (A1) (A2) (B1) (B2) (C1) (C2) (D1) and (D2). It is characterized in that an error signal is detected from the sum signal of the partition plates located in the diagonal direction by using all of b1) (b2) (c1) (c2) (d1) (d2).

That is, the circuit unit 450 obtains an error signal S1 'from the detection signals a1, b1, c1, and d1 of the outer partitions A1, B1, C1, and D1. A second circuit for obtaining the error signal S2 'from the circuit portion 350 and the detection signals a2, b2, c2 and d2 of the inner dividers A2, B2, C2 and D2. And a portion 150 and a circuit portion for detecting a slope error signal and / or a tracking error signal from the error signal S1 'and the error signal S2'.

The error signal S1 ′ is the same as the signal output from the error signal detecting apparatus of FIG. 14, and the first circuit portion 350 is the same as that of FIG. 14. The sum signal of the detection signals a1 and c1 of A1 and C1 is amplified to a predetermined gain k, and then the outer dividers B1 and D1 are arranged in a diagonal direction different from the amplified signal. The phases of the detection signals b1 and d1 are compared with the sum signal.

The error signal S2 ′ is the same as the signal output from the error signal detecting apparatus of FIG. 10, and the second circuit portion 150 includes the inner partition plates positioned in one diagonal direction as in FIG. 10. After amplifying the sum signal of the detection signals a1 and c1 of A2 and C2 with a predetermined gain k, the detection of the inner dividers B2 and D2 positioned in a diagonal direction different from the amplified signal is performed. The phases of the signals b2 and d2 are compared with the sum signal.

Here, since the circuit portions 150 and 350 have the same configuration as the circuit portions of FIGS. 10 and 14, they are denoted by the same reference numerals and detailed description thereof will be omitted.

Meanwhile, the error signal S1 'using the detection signal of the outer partitions A1, B1, C1 and D1 and the detection signal of the inner partitions A2, B2, C2 and D2 The phase characteristics of the used error signal S2 'are substantially the same as the error signal S1 and the error signal S2 described with reference to FIG.

Then, the circuit part configuration for detecting the inclination error signal and / or tracking error signal from the error signal S1 'and the error signal S2' and detecting the inclination error signal and / or tracking error signal with high precision and accuracy therefrom. The principle is as described with reference to FIG.

17 is a diagram schematically showing an error signal detection apparatus for an optical recording / reproducing apparatus according to another embodiment of the present invention. Referring to the drawings, an error signal detection apparatus for an optical recording / reproducing apparatus according to the present embodiment includes at least four partition plates for selectively receiving a portion of light that is reflected / diffracted on a recording medium and independently receiving photoelectric conversions. And a circuit unit 650 for calculating an error signal by calculating a detection signal of the photodetector 600.

In the present embodiment, the photodetector 600 includes first to fourth partition plates A and 2 arranged so that their row and column directions are substantially parallel to the radial direction and the track tangential direction of the recording medium. ) (B) (C) (D).

At this time, the first to fourth partitioning plate (A) (B) (C) (D) is spaced apart from each other by G _x1 , G _y1 in the radial direction and the track direction, respectively. Here, the first to fourth partition plates A, B, C, and D may be spaced apart from each other by G _{x1 in the} track direction of the outer partition plates A1, B1, C1, and D1 of FIG. 4. The phase relationship between the detection signals a, b, c and d of the first to fourth split plates A, B, C and D is substantially Therefore, the outer partitions A1, B1, C1, and D1 have the same phase relationship between the detection signals a1, b1, c1, and d1 of Hal.

However, by arranging the first to fourth divided plates A, B, C, and D so as to be spaced apart from each other by a predetermined interval, a partial region of the light that is reflected / diffracted on the recording medium is selectively received to generate an inclination error signal. If detected, the distortion of the tilt error signal is further improved, and a good tilt error signal can be detected.

Here, when the photodetector 600 for detecting the tilt error is made of the first to fourth split plates A, B, C, and D as described above, the photodetector 600 is the object of the optical pickup. It is preferably arranged to detect a part of the reflected light by the lens as a light spot on the recording medium. For example, in the optical structure of the optical pickup as shown in Fig. 1, the optical branch means is placed on the optical path between the optical path changing means such as the beam splitter 5 and the optical detection lens 8, and recorded by the optical branch means. The above-described inclination error detection photodetector 600 may be arranged to branch off a part of the light reflected / diffracted by the medium and to receive the split light. In this case, the optical recording / reproducing apparatus is provided with a photodetector for detecting information signals (9 in FIG. 1) and a photodetector 600 for detecting tilt error signals as described above.

Of course, information for detecting the information reproduction signal by receiving only a part of the light reflected / diffracted by the photodetector 600 including the first to fourth split plates A, B, C, and D on a recording medium. It is also possible to use both for signal detection and slope error signal detection.

On the other hand, the photodetector 600 is a four-sided inner partition plate of the bracket shape as indicated by the dashed line in Figure 17 in the separation region of the first to fourth partition plates (A) (B) (C) (D). The structure may further be provided.

In this case, the photodetector 600 has an at least eight division structure and receives all the light that is reflected / diffracted from the recording medium except for the partition boundary of each of the partition plates. Can be used as a signal detection combination.

The circuit unit 650 is similar to the circuit unit 50 of FIGS. 4, 7 and 8, and the detection signals (a) (b) of the first and second split plates A and B are located in the same row. The phases between the detection signals (c) and (d) of the third and fourth split plates (C) and (D) located in the same second row are compared with each other, and then an error signal is detected from the phase comparison signal. It can be arranged to do so. In addition, similar to the circuit unit 150 of FIGS. 9 and 10, the circuit unit 650 may be provided to obtain a sum signal of detection signals of the divided plates located in a diagonal direction, and then detect an error signal therefrom.

Here, although FIG. 17 illustrates an example in which the circuit unit 650 is provided in the same manner as the circuit unit 50 of FIG. 4, any one of the circuit unit configurations described in the above embodiments may be applied. The principle of detecting a signal or the like is the same as described in the foregoing embodiments, and thus detailed illustration and description thereof will be omitted.

FIG. 18 schematically shows an error signal detecting apparatus for an optical recording / reproducing apparatus according to another embodiment of the present invention, in which the circuit section 750 first compares phases between detection signals of the partition plates located in the same column, and thereafter. Its feature is that it is provided to detect an error signal. Here, the same reference numerals as those in FIG. 17 denote members having the same function, and thus description thereof will be omitted.

In the present embodiment, the circuit unit 750 receives a detection signal (a) (d) of the first and fourth split plates (A) (D) located in the second column and compares the phases of the first phase. A second phase comparator 753 which receives a comparator 751 and detection signals b and c of the second and third split plates B and C located in the first column and compares phases thereof; A differential 759 is provided to differential the phase comparison signal input from the first and second phase comparators 751 and 753.

In this way, when the error signal is detected by differentially comparing the phases between the detection signals of the partition plates located on the same line in the radial direction, the crosstalk caused by the adjacent track is caused by a high density disk having a narrow track. An error signal in which noise is greatly reduced can be detected.

Here, while the tracking servo is operated to track the on-track position of the light spot, the signal output from the circuit unit 750 becomes a slope error signal. Of course, when the tilt error is controlled so as not to occur, the error signal detection device of this embodiment can be used as a tracking error signal detection device.

Meanwhile, a low pass filter (60 in FIG. 7) or an envelope or signal center detector (70 in FIG. 8) is further provided at an output terminal of the circuit unit 750, regardless of whether or not a tracking servo operation is performed in the circuit unit 750. A signal corresponding to the slope error may be output.

19 and 20 show different embodiments of an optical detector 600 for an error signal detection apparatus for an optical recording / reproducing apparatus according to the present invention described with reference to FIGS. 17 and 18.

That is, as shown in FIG. 19, the photodetector 600 mainly detects an area closer to the center of the reflected / diffracted zeroth diffraction beam in the recording medium than in the cases shown in FIGS. 17 and 18. The first to fourth split plates A ', B', C ', and D' may be disposed to be spaced apart from each other by a predetermined interval G _y1 only in the track tangential direction. In addition, as shown in FIG. 20, the photodetector 600 has the first to fourth divided plates A ″, B ″, C ″, and D ″ only having a predetermined interval G in the radial direction. _x1 ) may be spaced apart from each other.

In this case, the first and second split plates A 'and B' in FIG. 19 correspond to a spaced area between the first and second split plates A and B in FIG. 17. The third and fourth splitter plates C 'and D' correspond to the spaced areas between the third and fourth splitter plates C and D of the photodetector of FIG. 17.

Similarly, the first and fourth partition plates A ″ and D ″ in FIG. 20 correspond to the spaced areas between the first and fourth partition plates A and D in FIG. 17. The second and third divider plates B ″ and C ″ correspond to spaced areas between the second and third divider plates B and C of FIG. 17.

Accordingly, the first through fourth split plates A ', B', C ', and D' have the inner dividers A2, B2, C2, and D2 of FIG. 4 in the track direction. Corresponding to the case where they are spaced apart from each other by _x1 , and the detection signals a '(b') (c ') of the first to fourth divided plates A' (B ') (C') and D '(c). The phase relationship between ') (d') is substantially the same as the phase relationship between the detection signals a2, b2, c2 and d2 of the inner partition plates A2, B2, C2 and D2. .

Further, the phase relationship between the detection signals a "(b") (c ") (d") of the first to fourth divided plates A ", B", C ", and D" It is substantially the same as the phase relationship between the detection signals (a) (b) (c) (d) of the first to fourth split plates (A) (B) (C) (D) of FIG.

In this case, the photodetector 600 of FIGS. 19 and 20 may further be used as an information reproduction signal detector of a recording medium in the case where the photodetector 600 has an eight-divided structure by further including a bracket-shaped partition region indicated by a dashed line in the drawing. Of course.

Herein, the first to fourth splitter structures of FIGS. 19 and 20 may be configured such that the angled inner partition plates of FIG. 17 are radially positioned at the same position as the boundary of the first to fourth splitter plates of FIGS. 19 and 20. When divided in the direction parallel to the tangential direction, it corresponds to the divided region between the first to fourth divided plates.

Therefore, when the photodetector 600 for the error signal detection apparatus according to the present invention has a 16-split structure that can include the partition plate structure of Figs. 17 to 20 as shown in Fig. 21, The 1st-4th partition board in FIGS. 17-20 corresponds to what selected and used one parting board in the said 16 division structure.

At this time, the 16-segment photodetector 600 is also used to detect the information reproduction signal of the recording medium.

Here, in the photodetector of FIGS. 17 to 21 as described above, the separation distance G _x1 and / or G _y1 between the first to fourth partition plates in the radial direction and / or the track direction is determined in the recording medium. It is preferred to be arranged to receive a portion of the 0th diffraction beam in the range of approximately 10% to 80% of the diameter of the 0th diffraction beam that is reflected / diffracted, or to receive an external portion thereof.

The separation distances G _x1 and G _y1 are determined to be optimized for the track pitch, the pit width, the pit length, the numerical aperture of the objective lens, the emitted light wavelength of the light source and the tangential tilt of the recording medium. Therefore, the error signal detecting apparatus for an optical recording / reproducing apparatus according to another embodiment of the present invention described with reference to Figs. 17 to 21 can detect a radial gradient error signal as a result.

On the other hand, in the error signal detecting apparatus for the optical recording / reproducing apparatus described with reference to Figs. 17 and 18, as shown in Fig. 22, the first to fourth divided plates A, B, C, and D are shown in Figs. A photodetector 700 may be provided in close proximity to each other so as to receive the center region of the zeroth order diffracted beam that is reflected / diffracted by the recording medium.

In this case, the phase relationship between the detection signals (a), (b), (c) and (d) of the first to fourth split plates A, B, C, and D is substantially the first in FIG. It is equal to the phase relationship between the detection signals a '(b') (c ') and d' of the fourth to fourth divisions A '(B') and C '(D').

In the error signal detection apparatus for the optical recording / reproducing apparatus according to the embodiments of the present invention as described above, the tilt error signal detected at the time of on-track is +1 degree radial tilt with respect to a predetermined reference level at the time of on-track. When the gradient error signals detected in the radial tilt state of −1 degrees are v1 and v2, respectively, the maximum value of the absolute value of (v1-v2) / (v1 + v2) is preferably about 0.2 or less.

Further, when the slope error signals detected in the radial tilt of +1 degree and the radial tilt of -1 degree are respectively v3 and v4 with respect to a constant reference level during off-tracking, the absolute minimum value of v1 or v2 is approximately the above. It is preferred that it is 30% of the v3 or v4 value.

In the error signal detection apparatus according to the embodiments of the present invention as described above, the phase comparator selectively blocks or amplifies according to the frequency band of the input signal, compares the phases of the binarized and binarized signals, and compares the phases. By integrating the signal may be provided to compare the phase of the input signal to each other and output.

The error signal detection apparatus according to the embodiments of the present invention as described above can detect a radial gradient error signal, and can be usefully employed in an optical recording / reproducing apparatus for a ROM type, in particular, an HD-DVD ROM disk. .

The error signal detection apparatus for an optical recording / reproducing apparatus according to the present invention as described above can detect an inclination error signal with high accuracy and precision even in an objective lens shift or a focus-off state, and provides a relative inclination between the recording medium and the objective lens. The tilt error signal can be detected sensitively.

Therefore, when the error signal detection apparatus according to the present invention is employed in a high density optical recording / reproducing apparatus using a short wavelength light source and an objective lens having a high aperture number, the relative inclination between the recording medium and the objective lens is controlled to provide a recording medium and an objective lens. Deterioration of the recording / reproducing signal due to coma aberration largely generated by the relative inclination between them can be prevented.

On the other hand, the error signal detection apparatus for an optical recording / reproducing apparatus according to the present invention as described above can be used for detecting a tracking error signal, and a differential amplifier and a circuit for detecting an error signal using both detection signals of inner and outer partitions. If an adder is added, the tilt error signal and the tracking error signal can be detected together.

Claims (35)

A photodetector for detecting an information signal for receiving reflected / diffracted light from a recording medium; And a circuit unit which calculates a detection signal of the photodetector to detect an error signal. The photodetector, Four light-receiving areas A1, A2 (B1, B2) (C1, C2) in which the row dividing boundary lines and the column dividing boundary lines are arranged in the counterclockwise direction substantially parallel to the radial direction and the track tangential direction of the recording medium. The inner dividing plate A2, B2, C2, D2 and the outer dividing plate A1, B1, C1, and D1 are divided by a dividing boundary line where D1 and D2 are substantially parallel to the track tangential direction, respectively. Into eight divided plates A1, A2, B1, B2, C1, C2, D1, D2, each of which is photoelectrically converted independently, and forms a 2x4 matrix arrangement. Done, The circuit portion, Error signal detection for an optical recording / reproducing device, characterized in that the phases between the detection signals of the inner and / or outer partition plates located in the same row are compared with each other, and then an inclination error signal is obtained from the phase comparison signal. Device. The method of claim 1, wherein the circuit portion, A first phase comparator for comparing the phases of the detection signals of the pair of inner division plates located in the first row with each other and outputting the phase comparison signal; A second phase comparator for comparing the phases of the detection signals of the remaining pair of inner division plates located in the second row with each other and outputting a phase comparison signal; And an adder for summing the phase comparison signals from the first and second phase comparators. The method of claim 1, wherein the circuit portion, A first phase comparator for comparing the phases of the detection signals of the pair of outer division plates located in the first row with each other and outputting the phase comparison signal; A second phase comparator for comparing the phases of the detection signals of the remaining pair of outer division plates located in the second row with each other and outputting a phase comparison signal; And an adder for summing the phase comparison signals from the first and second phase comparators. The method of claim 1, wherein the circuit portion, First and second phase comparators for comparing the phase between the detection signals of the outer partition plates positioned in the first row and the phase between the detection signals of the inner partition plates, respectively, and outputting a phase comparison signal; Third and fourth phase comparators for comparing the phase between the detection signals of the outer partition plates positioned in the second row and the phase between the detection signals of the inner partition plates, respectively, and outputting a phase comparison signal; A first adder for adding a phase comparison signal based on detection signals of the outer dividers from the first and third phase comparators and outputting a first phase sum signal; A second adder for adding a phase comparison signal based on detection signals of inner dividers from the second and fourth phase comparators and outputting a second phase sum signal; And a differential unit for differentially outputting an inclination error signal by differentiating first and second phase sum signals inputted from the first and second adders. The method of claim 4, wherein the circuit portion, And a third adder for summing the first and second phase sum signals inputted from the first and second adders and outputting a tracking error signal. The method of claim 4 or 5, wherein the circuit portion, Output stages of the first and / or second adders to correct amplitude differences of the first and second phase sum signals output from the first and second adders according to the split ratios of the inner and outer dividers of the photodetector. And a gain adjuster for amplifying the phase sum signal by the detection signals of the inner and outer partition plates to a predetermined gain. 6. The inner dividing plate of the photodetector according to any one of claims 1 to 5, wherein the inner dividing plates of the photodetector reflect approximately 10% to 80% of the zeroth order diffracted light incident on the recording medium by reflecting / diffusing the entire width thereof. An error signal detection device for an optical recording / reproducing device, characterized in that it is provided to receive light. 10. The method of claim 7, wherein the inner dividing plates have a zeroth order diffraction light and a + 1st order diffraction light among the incident zeroth order diffraction light and ± first order diffraction light whose total width along the radial direction is reflected / diffracted on the recording medium. Or an error signal detection device for an optical recording / reproducing apparatus, characterized in that it receives a region excluding a portion where the 0th-order diffracted light and the -1st-order diffracted light overlap. The circuit unit according to any one of claims 1 to 4, wherein A low pass filter for outputting the low-pass filtering the input signal to the output terminal; further comprising, it is possible to detect the relative inclination error degree between the objective lens and the recording medium irrespective of the tracking servo operation Error signal detection device for recording and playback equipment. The apparatus of claim 1, further comprising: a detector configured to detect an envelope of a signal output from the circuit unit or a center value change of the signal output from the circuit unit according to a relative inclination of the objective lens and the recording medium. And an inclination error signal can be detected even during a non-operation of the tracking servo. The slope error signal of any one of claims 1 to 4, which is detected at the time of on-track, When the slope error signals detected in the radial tilt of +1 degree and the radial tilt of -1 degree for the constant reference level at the time of on track are respectively v1 and v2, An error signal detection apparatus for an optical recording / reproducing apparatus, wherein the maximum value of the absolute values of (v1-v2) / (v1 + v2) is approximately 0.2 or less. The slope error signal of any one of claims 1 to 4, which is detected at the time of on-track, The slope error signals detected in the radial tilt of +1 degree and the radial tilt of -1 degree for the constant reference level at the time of on track are called v1 and v2, respectively, When the slope error signals detected in the radial tilt of +1 degree and the radial tilt of -1 degree for the constant reference level at the time of off-tracking are respectively v3 and v4, And the minimum value of the absolute value of v1 or v2 is approximately 30% of the value of v3 or v4. 4. An error signal detection apparatus for an optical recording / reproducing apparatus according to any one of claims 1 to 3, wherein the output signal of said circuit portion is used as a tracking error signal. The method of claim 13, wherein the circuit portion, A low pass filter provided at an output end thereof to pass a signal having a relatively low frequency gradient error component; And a differential to output a signal of a tracking error component by differentially dividing a signal including a tracking error component and a slope error component inputted by branching from the output terminal and a slope error component signal output from the low pass filter. An error signal detection apparatus for an optical recording / reproducing apparatus. A photodetector for receiving the reflected / diffracted light on the recording medium; And a circuit unit which calculates a detection signal of the photodetector to detect an error signal. The photodetector, Four light receiving regions A1, A2 (B1, B2) (C1, C2) in which the row dividing boundary line and the column dividing boundary line are arranged in the counterclockwise direction substantially parallel to the radial direction and the track tangential direction of the recording medium. (D1, D2) and the inner divider (A2) (B2) (C2) (D2) and the outer divider (A1) (B1) (C1) (D1) by a dividing boundary line substantially parallel to the track tangential direction, respectively. Eight split plates (A1) (A2) (B1) (B2) (C1) (C2) (D1) (D2) which are divided into two and divided into two, and each photoelectrically converts incident light independently, and forms a 2x4 matrix arrangement. Made of The circuit portion, By amplifying the detection signal of the inner and / or outer partition plate located in one diagonal direction with a predetermined gain, comparing the amplification signal with the phase comparison between the detection signal of the inner and / or outer partition plate located in another diagonal direction And an error signal detecting device for an optical recording / reproducing apparatus, characterized in that it is provided to obtain an inclination error signal from the phase comparison signal. The method of claim 15, wherein the circuit portion, A gain adjuster for amplifying the sum signal of the detection signals of the inner or outer dividing plate positioned in one diagonal direction to a predetermined gain; A phase comparator for comparing and outputting a phase between the sum signal of the detection signal of the inner or outer partition plates positioned in different diagonal directions and the output signal of the gain adjuster, and outputting an error signal for the optical recording / reproducing apparatus Device. The method of claim 16, wherein the circuit portion, And a delayer for time-delaying the detection signal of the inner or outer dividing plate located in one diagonal direction, to prevent phase degradation of an error signal due to a pit depth difference of the recording medium. Error signal detection device for playback equipment. The method of claim 15, wherein the circuit portion, First and second gain adjusters for amplifying the sum signal of the detection signals of the inner partition plates positioned in one diagonal direction and the sum signal of the detection signal of the outer partition plates with a predetermined gain, respectively; The phases between the sum signal of the detection signals of the inner dividers positioned in different diagonal directions, the output signal of the first gain regulator, the sum signal of the detection signals of the outer dividers, and the output signal of the second gain regulator are compared with each other. Outputting first and second phase comparators; And a differential unit for differentially outputting a slope error signal by differentially inputting the signals from the first and second phase comparators. The method of claim 18, wherein the circuit portion, And a third adder for summing the signals input from the first and second phase comparators to output a tracking error signal. The method of claim 18 or 19, wherein the circuit portion, Output therefrom to an output terminal of the first and / or second phase comparator so as to correct an amplitude difference of the phase comparison signal output from the first and second phase comparators according to the split ratio of the inner and outer splitters of the photodetector And a third gain adjuster for amplifying the phase comparison signal to a predetermined gain. 20. The optical divider according to any one of claims 15 to 19, wherein the inner dividers of the photodetectors reflect approximately 10% to 80% of the zeroth order diffracted light incident on the recording medium by its entire width along the radial direction thereof. An error signal detection device for an optical recording / reproducing device, characterized in that it is provided to receive light. 22. The zeroth-order diffraction light and the first-order diffraction light of claim 21, wherein the inner dividing plates have a total width along the radial direction of the incident zero-order diffraction light and the ± first-order diffraction light reflected / diffracted on the recording medium. Or an error signal detection device for an optical recording / reproducing apparatus, characterized in that it receives a region excluding a portion where the 0th-order diffracted light and the -1st-order diffracted light overlap. The circuit unit according to any one of claims 15 to 18, wherein A low pass filter for outputting the low-pass filtering the input signal to the output terminal; further comprising, it is possible to detect the relative inclination error degree between the objective lens and the recording medium irrespective of the tracking servo operation Error signal detection apparatus for recording and reproducing apparatus. 19. The apparatus of any one of claims 15 to 18, further comprising: a detector for detecting an envelope of a signal output from the circuit part or a center value change of the signal output from the circuit part according to a relative inclination of the objective lens and the recording medium. And an inclination error signal can be detected even during a non-operation of the tracking servo. 19. The tilt error signal according to any one of claims 15 to 18, which is detected at the time of on-track, When the slope error signals detected in the radial tilt of +1 degree and the radial tilt of -1 degree for the constant reference level at the time of on track are respectively v1 and v2, An error signal detection apparatus for an optical recording / reproducing apparatus, wherein the maximum value of the absolute values of (v1-v2) / (v1 + v2) is approximately 0.2 or less. 19. The tilt error signal according to any one of claims 15 to 18, which is detected at the time of on-track, The slope error signals detected in the radial tilt of +1 degree and the radial tilt of -1 degree for the constant reference level at the time of on track are called v1 and v2, respectively, When the slope error signals detected in the radial tilt of +1 degree and the radial tilt of -1 degree for the constant reference level at the time of off-tracking are respectively v3 and v4, And the minimum value of the absolute value of v1 or v2 is approximately 30% of the value of v3 or v4. 18. The error signal detection apparatus according to any one of claims 15 to 17, wherein the output signal of the circuit portion is used as a tracking error signal. A photodetector for detecting an information signal for receiving reflected / diffracted light from a recording medium; And a circuit unit which calculates a detection signal of the photodetector to detect an error signal. The photodetector selectively receives a portion of light that is reflected / diffracted from the recording medium to photoelectrically convert incident light independently, so that the row direction and the column direction are radial and track tangential directions of the recording medium. Consisting of at least four partition plates including first to fourth partition plates (A) (B) (C) (D) arranged to form a 2x2 matrix approximately parallel to The circuit unit is provided so as to compare phases between detection signals of the partition plates located in the same row or column with each other, and to detect a slope error signal from the phase comparison signal. Signal detection device. The method according to claim 28, wherein the first to fourth split plates (A) (B) (C) (D) of the photodetector, And an error signal detecting device for an optical recording / reproducing apparatus, wherein the radial and track directions are spaced apart from each other by G _x1 and G _y1 . The method according to claim 28, wherein the first to fourth split plates (A) (B) (C) (D) of the photodetector, And a predetermined interval (G _x1 ) in the radial direction or a predetermined interval (G _y1 ) in the track direction to be spaced apart from each other. 31. The method of claim 29 or 30, wherein the separation distance between the first to fourth split plates A, B, C, and D along the radial and / or track direction is the zero-order diffraction beam. An error signal detection apparatus for an optical recording / reproducing apparatus, characterized in that it receives a portion of a zeroth order diffraction beam in a range of approximately 10% to 80% of a diameter, or receives an external portion thereof. The method according to claim 28, wherein the first to fourth split plates (A) (B) (C) (D) of the photodetector, An error signal detection apparatus for an optical recording / reproducing apparatus, characterized by being disposed in close proximity to each other so as to receive a central region of the zeroth order diffracted beam reflected / diffracted on the recording medium. 33. The circuit according to any one of claims 28 to 30 or 32, wherein A first phase comparator for comparing phases between detection signals of the first and second split plates A and B positioned in a row and outputting a phase comparison signal; A second phase comparator for comparing the phases between the detection signals of the third and fourth divided plates C and D located in another row and outputting the phase comparison signal; And an adder for summing the phase comparison signals from the first and second phase comparators and outputting an inclination error signal. 33. The circuit according to any one of claims 28 to 30 or 32, wherein A first phase comparator for comparing phases between detection signals of the first and fourth split plates A and D positioned in one column and outputting a phase comparison signal;  A second phase comparator for comparing phases between detection signals of the second and third splitter plates B and C located in different columns and outputting a phase comparison signal; And a differential unit for differentially outputting a gradient error signal by differentially comparing phase comparison signals from the first and second phase comparators. 33. The light detector according to any one of claims 28 to 30 or 32, wherein It consists of at least eight divided structures further comprising four partition plates inside or outside the first to fourth partition plates A, B, C, and D, and used for detecting the information signal of the recording medium. And an error signal detection device for an optical recording / reproducing device.

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