JP2004303419A - Optical disk system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize high-speed and stable focus control of a two-focus head or a disk, having a plurality of information surfaces. <P>SOLUTION: In starting or restarting of a system, when a focal lens is moved close to a disk and then moved away from it, or moved away from the lens and then moved close to it; the amplitude of a S-shaped signal is measured, which appears on FE each time the focal point of the optical beam passes through each information surface, the gain of a focus detection system is switched such that the amplitude becomes a predetermined value, and thus an optimum drawing level is established. Then, when the lens is moved away from the disk from the uppermost point (CD), or when it is moved close to the disk from the lowermost point (DVD), the focus control is operated on the information surface to which the focal point of the optical beam initially reaches and the drawing is completed. Thereafter, once the focus control is set inactive, the speed of the focal lens is increased/decreased, based on the FE signal level and the drawing level established on each information surface, and then the control is shifted to the next information surface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical recording / reproducing apparatus that optically records a signal on a recording medium using a light beam from a light source such as a laser, and reproduces the recorded signal, The present invention relates to an optical recording / reproducing apparatus including a focus control device that controls a convergence state of an irradiated light beam to a predetermined convergence state.

  As a conventional optical recording / reproducing apparatus, as described in Japanese Patent Application Laid-Open No. 7-129968, a disc-shaped recording medium rotating at a predetermined rotational speed is convergently irradiated with a light beam generated from a light source such as a semiconductor laser. There is an optical recording / reproducing apparatus for recording / reproducing a signal. On the disc-shaped recording medium, minute tracks having a width of about 0.6 μm and a pitch of 1.5 μm are provided in a spiral or concentric manner. In order to record a signal on this track or to reproduce a signal recorded on the track, these optical recording and reproducing apparatuses use such an optical recording and reproducing apparatus that a light beam irradiated on a recording medium is brought into a predetermined converged state. Focus control is performed.

  FIG. 19 is a block diagram showing a simple configuration of an optical recording / reproducing device including such a conventional focus control device. Hereinafter, a conventional focus control device will be described with reference to FIG.

  As shown in FIG. 19, this conventional recording / reproducing apparatus includes a light source 1, such as a semiconductor laser, which is an optical system for irradiating a disk 7, which is a recording medium, with a light beam 8, a coupling lens 2, a polarization beam splitter 3, and the like. , A polarizing plate 4, a converging lens 5, and a disk motor 6 for rotating the disk 7 at a predetermined rotation speed. The light beam 8 generated from the light source 1 is made parallel by the coupling lens 2. After being reflected by the polarizing beam splitter 3, the parallel light passes through the polarizing plate 4, is converged by the converging lens 5, and is emitted to the rotating disk 7 by the disk motor 6.

  This optical recording / reproducing apparatus further includes a condenser lens 9 and a split mirror 10 as elements for receiving the reflected light from the disk 7. The reflected light from the disk 7 passes through the converging lens 5, the polarizing plate 4, and the polarizing beam splitter 3, and is split into two light beams 11 and 15 by a split mirror 10 via a condenser lens 9. . The light beams 11 and 15 are input to a focus control device and a tracking control device, respectively.

  The focus control device includes a photodetector 12, a preamplifier 13A and 13B, a differential amplifier 14, a phase compensation circuit 18, a linear motor 19, a switch 33, a drive circuit 35, a focus control element (focus actuator) 36, a logic It comprises a circuit 40, a comparator 41, and a triangular wave generator 42. The photodetector 12 has two light receiving sections A and B. Output signals from the respective light receiving sections A and B are input to the differential amplifier 14 after being amplified by the preamplifiers 13A and 13B, respectively. Here, the knife edge detection method can be realized by the condenser lens 9 and the split mirror 10, and the output signal of the differential amplifier 14 becomes a focus error signal (FE; Focus Error signal).

  The focus shift signal FE is compensated for the phase of the focus control system by the phase compensation circuit 18 and is input to the drive circuit 35 via the switch 33 for closing the loop of the focus control system. When the focus control system is closed by the switch 33, the drive circuit 35 power-amplifies the FE from the phase compensation circuit 18 and outputs the amplified FE to the focus control element 36. With such a configuration, the focus control element 36 is driven such that the light beam on the disk always has a predetermined convergence state when the focus control system is closed. The switch 33 also receives the output signal of the triangular wave generator 42. The FE is also input to the logic circuit 40 via the comparator 41. The logic circuit 40 controls opening and closing of the switch 33.

  The linear motor 19 moves the converging lens 5, the focus control element 36, the polarization beam splitter 3 and the like in a direction crossing the tracks on the disk 7, and usually moves the convergence point of the light beam to a predetermined track. To work.

  On the other hand, the other light beam 15 split by the split mirror 10 is input to a two-divided photodetector 16 of the tracking control device. The photodetector 16 has two light receiving sections C and D, and the difference output signal between the output signals from each of the light receiving sections C and D is controlled so that the light beam on the disk 7 scans the track correctly. Track deviation signal (TE) for performing the operation. Since the tracking control is not directly related to the features of the present invention, a detailed description is omitted here, and a necessary description will be given in the following embodiments.

  In an optical recording / reproducing apparatus having a focus control device having such a configuration, focus control is performed as follows.

  First, the disk 7 is rotated by the disk motor 6, and when a predetermined rotation is reached, the switch 33 is switched to the triangular wave generator 42 side, and the focus control element 36 is driven by the signal from the triangular wave generator 42 in a triangular wave. The converging lens 5 is moved up and down in a direction perpendicular to the recording surface of the disk 7. Accordingly, this causes the convergence point of the light beam on the disk 7 to rise and fall. At this time, the comparator 41 detects an S-shaped FE (hereinafter referred to as an S-shaped signal) appearing when the convergence point of the light beam passes through the recording surface. By detecting this S-shaped signal, the logic circuit 40 can know whether or not the convergence point of the light beam exists near the recording surface. Switch to the compensation circuit 18 side. By closing the focus control loop in this way, an operation of focus control (focus pull-in) for positioning the light beam at a predetermined optimum target position is performed.

  This focus pull-in operation will be described with reference to FIGS. 20, 21, and 22. FIG. FIG. 20 is a waveform diagram of a converging lens drive signal at the time of focusing pull-in and an S-shaped signal appearing on the FE. FIG. FIG. 22 is a waveform chart showing the relationship between the S level signal on the surface protective film and the recording film and the pull-in level, and FIG. 22 is a simple flowchart showing the basic focus pull-in procedure in this focus control device.

  As shown in FIG. 22, when the power of the recording / reproducing apparatus is turned on, the disk motor 6 is turned on in step S21, and the disk 7 is rotated. When the disk 7 reaches a predetermined number of revolutions, in step S22, the light source 1 is turned on, and, for example, a semiconductor laser emits light. Subsequently, in step S23, the linear motor 19 operates to move the converging lens 5 toward the inner circumference of the disk 7. When the above initial operation is completed, a focus pull-in operation is started.

  In the focus pull-in operation, first, as shown in FIG. 20, the converging lens 5 is lowered and separated from the disk 7 in step S24 by the output signal from the triangular wave generator 42, and the converging lens 5 is raised in step S25. It is made to approach the disk 7. While repeating the separation and approach of the converging lens 5, it is detected in step S26 that the S-shaped signal has reached a predetermined pull-in level. After reaching the predetermined pull-in level, the switch 33 is switched to the phase compensation circuit 18 side by the logic circuit 40, the vertical movement of the converging lens 5 is stopped in step S27, and the focus control is turned on in step S28. Then, the pull-in operation ends, and the focus control is started.

  The detection level (pull-in level) of the comparator 41 for pulling in the focus is defined by the amplitude of the S-shaped signal output by each of the reflection of the recording film and the reflection of the protective film of the disk 7, and as shown in FIG. It is set to a linear section larger than the peak of the S-shaped signal of the protective film and between the peak of the S-shaped signal of the recording film and zero.

In the conventional optical recording / reproducing apparatus, the pull-in operation of the focus control is realized by the above-described method.
In such a conventional method, the convergence point of the light beam passes through each information surface of a large-capacity disk (for example, a digital video disk, hereinafter referred to as a DVD) having two or more information surfaces on one side as shown in FIG. Each time a converging lens is pulled up or down at the time of pull-in, S-characters appear as many as the number of information surfaces. For example, in a two-layer DVD disc, as shown in FIG. 7, in addition to a small S-shape of the protective film, a two-cycle S-shape on each information surface appears. Therefore, in the conventional focus control device, the S-shape of the protective film on the surface is erroneously detected, and the focus control is turned on at that portion to fail in the pull-in. Was turned on, so it was not possible to know which side of the two layers was pulled in. Therefore, it has been extremely difficult to reliably select either the upper surface or the lower surface of the two layers, perform focus control, and perform tracking control to reproduce information.

  In an optical head using a hologram element such as 106 in FIG. 1 so that reproduction compatibility can be performed between DVD and CD, an image is formed at two focus points such as 107a and 107b in FIG. Due to the influence of these two beams, in a disc such as a CD having a single information surface, an S-character at each focus point appears at the time of pull-in, and it is difficult to determine which focus point to pull-in. In addition, in the case of a DVD double-layer disc, as shown in FIG. 7, at least six S-characters appear on the FE by one UP or DOWN at the time of pulling in, and when the disc has a large runout, Since the respective S-characters interfere with each other and become non-linear, the amplitude of the S-character is measured to learn the pull-in level, and the pull-in control is performed by reliably detecting the drawing-in surface. It had become almost impossible.

  In the case of a two-layer disc or a multi-layer disc having more layers, the eccentricity, the focus offset value, the tracking offset value, the focus gain value, the tracking gain value, and the focus shift amount during the search are different on each information surface. Even if these correction values are optimally set on one surface, if the light beam is shifted to another information surface and reproduction or recording is only to be performed, a large focus shift or track shift occurs there, The focus control and the tracking control become unstable. In addition, when searching for a track, the focus shift was particularly large due to the effect of crossing the groove, and a stable search could not be performed.

  Further, the conventional optical recording / reproducing apparatus does not support various discs such as a single-layer disc of CD and DVD, a double-layer disc of DVD, and a write-once disc such as CD-R and DVD-R. When a disc that is not compatible with the device is mounted, an error is only displayed or the disc is forcibly ejected.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and a head for irradiating a light beam to a two-layer disc or a multi-layer disc, or further, to the disc, has a base material. It is an object of the present invention to provide an optical recording / reproducing apparatus which can perform high-speed and stable focus control pull-in even in a case where the head has two focal points corresponding to disks having different thicknesses.

  In addition, high-speed and stable movement between layers can be performed, and stable focus, tracking, and track search performance can be secured in any layer, and it is compatible with a large-capacity two-layer or multilayer disk. It is an object of the present invention to provide a highly reliable optical recording / reproducing apparatus.

  In order to solve the above-mentioned problems, an optical disc apparatus according to claim 1 of the present invention comprises a converging means for converging and irradiating a light beam on a record carrier having two information surfaces, and a light beam converged by the converging means. Moving means for moving the convergence point in a direction substantially perpendicular to the information surface of the record carrier; light detecting means for receiving reflected light of the converged light beam from the record carrier; Based on an output signal of the means, a convergence state of the light beam irradiated on the information surface is detected, and the moving means is driven based on the detection signal, so that the convergence state of the light beam is a predetermined state. Focus control means for controlling the movement of the light beam to move the convergence point of the light beam from the first information surface to the second information surface of the record carrier; and Bi When the moving means is driven to move the recording medium away from or closer to the record carrier and passes through the first and second information surfaces, a signal corresponding to the amount of reflected light obtained from the light detecting means is stored. A reflection light amount storage means for performing the focus jumping by the focus jumping means, wherein the gain of the focus control means is switched according to a value stored in the reflection light amount storage means. Is what you do.

  In the optical disk device according to claim 2 of the present invention, in the optical disk device according to claim 1, when the focus jumping is performed by the focus jumping unit, the focus light amount is stored according to a value stored in the reflected light amount storage unit. The focus control pull-in level is set.

  According to a third aspect of the present invention, there is provided the optical disk device according to the first aspect, wherein the optical disk device responds to an output signal of a focus control unit that switches a gain according to a value stored in the reflected light amount storage unit. Thus, the focus control pull-in level at the time of focus jumping is set.

  An optical disc apparatus according to a fourth aspect of the present invention includes a converging means for converging and irradiating a light beam on a record carrier having two information surfaces, and a convergence point of the light beam converged by the converging means. Moving means for moving in a direction substantially perpendicular to the information surface of the record carrier; light detecting means for receiving reflected light of the converged light beam from the record carrier; and an output signal from the light detecting means. Detecting a convergence state of the light beam irradiated on the information surface, driving the moving means based on the detection signal, and controlling the convergence state of the light beam to a predetermined state. Control means; focus jumping means for driving the moving means to move the convergence point of the light beam from the first information surface to the second information surface of the record carrier; and moving the light beam away from the record carrier. Convergence state detection signal storage means for storing the convergence state detection signal, which is obtained when the moving means is driven so as to move or move closer to each other and passed through the first and second information surfaces, When the focus jumping is performed by the focus jumping means, the gain of the focus control means is switched according to the value stored in the convergence state detection signal storage means.

  According to a fifth aspect of the present invention, in the optical disk device according to the second aspect, when the focus jumping is performed by the focus jumping means, the focus convergence state detection signal is stored in accordance with the value stored in the convergence state detection signal storage means. , A focus control pull-in level is set.

  According to a sixth aspect of the present invention, there is provided the optical disk device according to the second aspect, wherein the signal of the focus control unit that switches the gain in accordance with the value stored in the convergence state detection signal storage unit. The pull-in level of the focus control at the time of the focus jumping is set accordingly.

  An optical disc apparatus according to a seventh aspect of the present invention includes a converging means for converging and irradiating a light beam on a record carrier having two information surfaces, and a converging point of the light beam converged by the converging means. Moving means for moving in a direction substantially perpendicular to the information surface of the recording medium, light detecting means for receiving reflected light from the record carrier, and reflected light quantity for detecting a signal corresponding to the reflected light quantity obtained from the light detecting means A convergence state detection means for detecting a convergence state of the light beam irradiated on the information surface based on an output signal of the detection means and the light detection means, and a signal of the convergence state detection means as a signal of the reflected light amount detection means And a focus jumper for driving the moving means based on a signal from the dividing means to move a convergence point of the light beam from the first information surface to the second information surface of the record carrier. It is characterized in that a means.

  Also, an optical disc apparatus according to claim 8 of the present invention comprises a converging means for converging and irradiating a light beam on a record carrier, and a convergence point of the light beam converged by the converging means on an information surface of the record carrier. Moving means for moving in a substantially vertical direction; light detecting means having at least two light receiving areas for receiving reflected light from the record carrier; and a difference between output signals from the two light receiving areas of the light detecting means. Convergence state detection means for detecting the convergence state of the light beam irradiated on the information surface, and driving the moving means based on an output signal of the convergence state detection means, based on the convergence of the light beam. Focus control means for controlling the state to a predetermined state, and the light beam, in the direction perpendicular to the track on the record carrier, a search means for searching for a desired track, The convergence state detecting means detects a peak level of an output signal from two light receiving areas of the light detecting means when searching for a desired track by the searching means, and obtains the information based on a difference between the two peak level detection signals. The convergence state of the light beam irradiated on the surface is detected.

  An optical disk device according to a ninth aspect of the present invention is an optical disk device for reproducing information recorded on a record carrier by converging and irradiating a light beam onto a record carrier having two information surfaces. Moving means for moving the light beam on the record carrier across the track; detecting a displacement between the light beam on the record carrier and the track; and moving the moving means in accordance with the track displacement signal. Tracking control means for driving and controlling the light beam on the record carrier so as to be positioned on the track; and controlling the light beam to a position on the first information surface and a position on the second information surface of the record carrier. Focus jumping means for performing interlaced scanning between the first and second information surfaces of the record carrier when the focus information is interlacedly scanned by the focus jumping means. Eccentric signal storage means for storing eccentric signals corresponding to the eccentricity of the track on the surface respectively; adding means for adding the eccentric storage signal stored in the eccentric signal storage means to the output signal of the tracking control means; A system control unit that controls the eccentricity storage signal read from the eccentricity signal storage unit corresponding to the information plane to be skipped to be added to the tracking control unit when performing interlaced scanning by the focus jumping unit. It is a feature.

  An optical disc device according to claim 10 of the present invention is an optical disc device that converges and irradiates a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier. Moving means for moving the light beam on the record carrier so as to cross the track, detecting a positional shift between the light beam on the record carrier and the track, and moving the moving means in accordance with the track shift signal. Tracking control means for driving and controlling the light beam on the record carrier so as to be positioned on the track; and controlling the light beam to be positioned on the first information surface and on the second information surface of the record carrier. Focus jumping means for performing interlaced scanning between the first and second information surfaces of the record carrier when the information surface is interlacedly scanned by the focus jumping means. Tracking gain storage means for respectively storing a desired loop gain of the tracking control means on the report surface; and multiplication means for multiplying a signal of the tracking control means by a tracking gain storage signal stored in the tracking gain storage means. When the interlaced scanning is performed by the focus jumping means, control is performed such that the output signal of the tracking control means is multiplied by the tracking gain storage signal read from the tracking gain storage means and corresponding to the information plane to be skipped. And a system control means.

  An optical disc apparatus according to claim 11 of the present invention is an optical disc apparatus that converges and irradiates a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier. Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier; light detecting means for receiving reflected light from the record carrier; A convergence state of the light beam irradiated on the information surface is detected based on an output signal of the light detection means, and the moving means is driven based on the detection signal, so that the convergence state of the light beam is a predetermined state. Focus control means for controlling the light beam to jump between a position on the first information surface and a position on the second information surface of the record carrier; Focus gain storage means for storing desired loop gains of the focus control means on the first information face and the second information face of the record carrier when the information face is skipped and scanned by the cas jumping means, respectively; Multiplying means for multiplying the output signal of the focus control means by a focus gain storage signal stored in the focus gain storage means, and the focus corresponding to the information surface to be skipped when performing the interlaced scanning by the focus jumping means. System control means for controlling the focus gain storage signal read from the gain storage means to be multiplied by the signal of the focus control means.

  An optical disk device according to a twelfth aspect of the present invention is an optical disk device that converges a light beam onto a record carrier having two information surfaces and reproduces information recorded on the record carrier. Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier; and light detecting means for receiving reflected light from the record carrier, The convergence state of the light beam irradiated on the information surface is detected based on the output signal of the light detection means, and the moving means is driven based on the detection signal, so that the convergence state of the light beam is in a predetermined state. Focus control means for controlling the light beam to jump between a position on the first information surface and a position on the second information surface of the record carrier; and Focus position storage means for storing desired target positions of the focus control means on the first information surface and the second information surface of the record carrier when the information surface is skipped and scanned by the focus jumping means, respectively; When the interlaced scanning is performed by the focus jumping unit, the target position of the focus control unit is determined by adding the target position of the focus control unit to the focus position storage signal read from the focus position storage unit corresponding to the information plane to be jumped. System control means for controlling the position to be switched.

  An optical disk device according to a thirteenth aspect of the present invention is an optical disk device that converges and irradiates a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier. Moving means for moving the light beam on the record carrier across the track, detecting a displacement between the light beam on the record carrier and the track, and driving the moving means in accordance with the track displacement signal. Tracking control means for controlling the light beam on the record carrier to be positioned on the track; and controlling the light beam between a position on the first information surface and a position on the second information surface of the record carrier. Focus jumping means for performing interlaced scanning with the first and second information surfaces of the record carrier when the information surface is interlacedly scanned by the focus jumping means. A tracking position storage means for storing a desired target position of the tracking control means, and a target position of the tracking control means corresponding to an information plane to be jumped when the focus jumping means performs interlaced scanning. The system further comprises system control means for controlling switching to the tracking position storage signal read from the tracking position storage means.

  An optical disc apparatus according to a fourteenth aspect of the present invention provides a converging means for converging and irradiating a light beam onto a record carrier having two information surfaces, and a convergence point of the light beam converged by the converging means. Moving means for moving in a direction substantially perpendicular to the direction of the surface and the track, light detecting means for receiving reflected light from the record carrier in a plurality of divided areas, and light receiving areas of the light detecting means Phase difference track shift detecting means for generating a phase difference track shift signal corresponding to the positional relationship between the convergence point of the light beam on the information surface and the track based on the phase relationship of the output signal; Tracking control means for driving the moving means in accordance with the output signal of the means and controlling the convergence point of the light beam on the record carrier to scan the track correctly; and A focus jumping means for performing interlaced scanning between a position on the first information surface and a position on the second information surface of the record carrier; and the recording when the information surface is interleaved and scanned by the focus jumping means. The amount of signal advance or delay in each light receiving area of the light detecting means so that the output signal of the phase difference track deviation detecting means on the first information surface and the second information surface of the carrier becomes a desired output. The phase canceling amount storing means for storing the amount and the delay amount or the advance amount of the signal of each light receiving area of the light detecting means when performing the interlaced scanning by the focus jumping means correspond to the information surface to be skipped. System control means for controlling switching to the phase cancellation amount storage signal read from the phase cancellation amount storage means. It is an butterfly.

  According to the optical disk apparatus of the present invention, a converging means for converging and irradiating a light beam on a record carrier having two information surfaces and a convergence point of the light beam converged by the converging means are recorded on the recording medium. Moving means for moving in a direction substantially perpendicular to the information surface of the carrier, light detecting means for receiving the reflected light of the converged light beam from the record carrier, and an output signal of the light detecting means Focus control for detecting a convergence state of a light beam irradiated on the information surface, driving the moving means based on the detection signal, and controlling the convergence state of the light beam to a predetermined state. Means for driving the moving means to move the convergence point of the light beam from the first information surface to the second information surface of the record carrier; and moving the light beam away from the record carrier. And a reflected light amount storage means for storing a signal corresponding to the reflected light amount obtained from the light detecting means when the moving means is driven to pass through the first and second information surfaces so as to be close to or closer to each other. When the focus jumping is performed by the focus jumping means, the gain of the focus control means is switched in accordance with the value stored in the reflected light amount storage means. Even if the amount of return light from the surface fluctuates and the amplitude of the S-shape changes, or if the S-shape amplitude of the FE signal fluctuates for each disk, device, or head, it is sufficient to cope with this. The effect that the focus jumping can be operated stably can be obtained.

  Further, according to the optical disk device of the present invention, in the optical disk device according to the first aspect, when the focus jumping is performed by the focus jumping unit, the focus jumping is performed according to the value stored in the reflected light amount storage unit. By setting the pull-in level of the focus control, calculating the pull-in level at the time of focus jumping, and providing this independently, it is possible to obtain the effect of realizing a more stable pull-in.

  According to a third aspect of the present invention, in the optical disk device according to the first aspect, the output signal of the focus control unit that switches the gain in accordance with the value stored in the reflected light amount storage unit. Accordingly, the pull-in level of the focus control at the time of the focus jumping is set, so that the amount of return light from each information surface of a two-layer or multi-layer disk varies, and the S-shaped amplitude of each disk, device, and head varies. The effect that the focus jumping can be operated stably even with respect to variations and the like can be obtained.

  According to the optical disc apparatus of claim 4 of the present invention, a converging means for converging and irradiating a light beam onto a record carrier having two information surfaces, and a convergence point of the light beam converged by the converging means, Moving means for moving in a direction substantially perpendicular to the information surface of the record carrier; light detecting means for receiving reflected light of the converged light beam from the record carrier; and an output signal of the light detecting means. Based on the detection signal, the convergence state of the light beam irradiated on the information surface is detected, and the moving means is driven based on the detection signal, so that the convergence state of the light beam is controlled to a predetermined state. Focus control means; focus jumping means for driving the moving means to move the convergence point of the light beam from the first information surface to the second information surface of the record carrier; and transferring the light beam from the record carrier. Far And a convergence state detection signal storage means for storing the convergence state detection signal obtained when the moving means is driven so as to move or approach the first and second information surfaces. When the focus jumping is performed by the focus jumping means, the gain of the focus control means is determined by adjusting the gain of the FE estimated from the amplitude of the AS signal, the RF signal, or the envelope detection signal stored in the convergence state detection signal storage means. By setting the value based on the amplitude value and setting the pull-in level in accordance with the S-shaped amplitude of the FE signal after the gain switching, the information from each information surface of the two-layer or multi-layer disc can be obtained. Even if the return light amount varies and the S-shaped amplitude changes, Even though variations in S-curve amplitude, etc. of the FE signal, adequately corresponding to this variation, the effect that can be operated stably obtain the focus jumping.

  According to the optical disk apparatus of the present invention, when the focus jumping is performed by the focus jumping means, the optical disk apparatus according to the fourth aspect of the present invention responds to the value stored in the convergence state detection signal storage means. By setting the pull-in level of the focus control and calculating the pull-in level at the time of focus jumping and independently providing the pull-in level, an effect that a more stable pull-in can be realized is obtained.

  According to a sixth aspect of the present invention, in the optical disk device according to the fifth aspect, the focus control means for changing the gain in accordance with the value stored in the convergence state detection signal storage means. Variations in the amount of light returned from each information surface of a two-layer or multi-layer disc in which the pull-in level of focus control is set in accordance with the signal, and the S-shaped amplitude of each disc, device, and head The effect that the focus jumping can be operated stably even with respect to variations and the like can be obtained.

  According to the optical disk apparatus of the present invention, a converging means for converging and irradiating a light beam onto a record carrier having two information surfaces, and a convergence point of the light beam converged by the converging means are recorded. Moving means for moving in a direction substantially perpendicular to the information surface of the carrier, light detecting means for receiving light reflected from the record carrier, and reflection for detecting a signal corresponding to the amount of reflected light obtained from the light detecting means A convergence state detection means for detecting a convergence state of the light beam irradiated on the information surface based on an output signal of the light amount detection means and the light detection means; A dividing means for dividing by a signal; and a focus jumper for driving the moving means based on a signal from the dividing means to move a convergence point of the light beam from the first information surface to the second information surface of the record carrier. Means, the FE signal to be sampled at the time of focus jumping is converted to a signal obtained by dividing the FE signal by the total light amount signal AS, or the set gain of the gain switching circuit is changed according to the amplitude of the total light amount signal AS. Even if the reflectance on the first and second information surfaces or on the inside, middle, and outer circumferences of the disc greatly varies, the pull-in level of the information surface of the jump destination can be accurately determined by making the signals always switched. Can be detected.

  According to the optical disk apparatus of the present invention, a convergence means for converging and irradiating a light beam on a record carrier, and a convergence point of the light beam converged by the convergence means are recorded on an information surface of the record carrier. Moving means for moving in a direction substantially perpendicular to the optical axis, light detecting means having at least two light receiving areas for receiving reflected light from the record carrier, and output signals from the two light receiving areas of the light detecting means. Based on the difference, a convergence state detecting means for detecting a convergence state of the light beam irradiated on the information surface, and driving the moving means based on an output signal of the convergence state detection means, Focus control means for controlling the convergence state to a predetermined state, and the light beam, in the direction perpendicular to the track on the record carrier, a search means for searching for a desired track, The convergence state detecting means detects a peak level of an output signal from two light receiving areas of the light detecting means when searching for a desired track by the searching means, and obtains the information based on a difference between both peak level detection signals. Since the convergence state of the light beam irradiated on the surface is configured to be detected, the normal tracking control is turned on for defocus generated at the time of search due to adjustment error of the optical element etc. By switching between the focus control of (1) and the FE input under the focus control during the search, the defocus due to the influence of the track cross can be suppressed, and the counting error during the search and the focus jump can be prevented. The effect that stable search performance can be secured is obtained.

  Further, according to the optical disk device of the ninth aspect of the present invention, the optical disk device reproduces information recorded on the record carrier by converging and irradiating a light beam onto a record carrier having two information surfaces. Moving means for moving the light beam on the record carrier so as to cross the track; detecting a positional shift between the light beam on the record carrier and the track; and moving the moving means in accordance with the track shift signal. And a tracking control means for controlling the light beam on the record carrier to be positioned on the track, and the light beam on the first information surface and the second information surface of the record carrier. Focus jumping means for performing interlaced scanning between the first information surface and the second information surface when the interlaced scanning is performed by the focus jumping means. Eccentricity signal storage means for storing eccentricity signals corresponding to the eccentricity, addition means for adding the eccentricity storage signal to the output signal of the tracking control means, and interlaced scanning when performing interlaced scanning by the focus jumping means. System control means for controlling the eccentric storage signal read from the eccentric signal storage means corresponding to the information surface so as to be added to the tracking control means. By switching the eccentricity information used to generate the correction signal according to the plane, it is possible to improve the followability with respect to the eccentricity, and it is possible to construct a tracking control system that is always responsive to the eccentricity. Is obtained.

  Further, according to the optical disk apparatus of claim 10 of the present invention, the optical disk apparatus reproduces information recorded on the record carrier by converging and irradiating a light beam onto a record carrier having two information surfaces. Moving means for moving the light beam on the record carrier across the track; detecting a positional shift between the light beam on the record carrier and the track; and moving the moving means in accordance with the track shift signal. And a tracking control means for controlling the light beam on the record carrier so as to be positioned on the track; and controlling the light beam to be positioned on the first information surface and on the second information surface of the record carrier. Focus jumping means for performing interlaced scanning between the first information surface and the second information surface when the information surface is interlacedly scanned by the focus jumping means. A tracking gain storage unit for storing a desired loop gain of the tracking control unit; a multiplication unit for multiplying the tracking gain storage signal by a signal of the tracking control unit; And a system control means for controlling so as to multiply an output signal of the tracking control means by a tracking gain storage signal read from the tracking gain storage means corresponding to the information surface to be interlacedly scanned. In a two-layer disc, the tracking gain is learned when moving from one information surface to the other information surface, and the tracking gain is stored according to the target information surface when each information surface is stored during a focus jump. To the optimal value of Ri, in any of the information plane, the effect that can build a stable tracking control system is obtained.

  Further, according to the optical disk device of the present invention, an optical disk device for converging and irradiating a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier. Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier; light detecting means for receiving light reflected from the record carrier; The convergence state of the light beam irradiated on the information surface is detected based on the output signal of the light detection means, and the moving means is driven based on the detection signal, so that the convergence state of the light beam is in a predetermined state. Focus control means for controlling the light beam to jump between a position on the first information surface and a position on the second information surface of the record carrier; and Focus gain storage means for storing desired loop gains of the focus control means on the first information surface and the second information surface of the record carrier when the information surface is skipped and scanned by the cas jumping means, respectively; A multiplying means for multiplying the output signal of the focus control means by the focus gain storage signal; System control means for controlling the storage signal to be multiplied by the signal of the focus control means, so that when moving from one information surface to the other information surface in a two-layer disc, the focus gain is increased. Learn and focus gain according to its intended information surface , By switching to an optimum value of the respective information surface stored during the focus jump, in any of the information plane, there is an effect that it is possible to construct a stable focus control system.

  Further, according to the optical disc apparatus of the present invention, an optical disc apparatus for reproducing information recorded on the record carrier by converging and irradiating a light beam onto a record carrier having two information surfaces. Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier; and light detecting means for receiving reflected light from the record carrier. Detecting a convergence state of a light beam irradiated on the information surface based on an output signal of the light detection means, driving the moving means based on the detection signal, and determining whether the convergence state of the light beam is a predetermined value. Focus control means for controlling the recording medium to be in a state; focus jumping means for causing the light beam to perform a jump scan between a position on the first information surface and a position on the second information surface of the record carrier; Focus position storage means for storing desired target positions of the focus control means on the first information surface and the second information surface of the record carrier when the information surface is skipped and scanned by the focus jumping means, respectively; At the time of interlaced scanning by the focus jumping means, system control for controlling to switch the target position of the focus control means to a focus position storage signal read from the focus position storage means corresponding to the information surface to be jumped. Means for learning the focus position when moving from one information surface to the other information surface in a two-layer disc, and performing a focus jump according to the target information surface. By switching to the optimal value of each information surface stored at the time, Also in the information plane of the shift, there is an effect that it is possible to construct a stable focus control system.

  Further, according to the optical disk apparatus of the present invention, an optical disk apparatus for reproducing information recorded on the record carrier by converging and irradiating a light beam onto a record carrier having two information surfaces. Moving means for moving the light beam on the record carrier so as to cross the track; and detecting a positional shift between the light beam on the record carrier and the track, and driving the moving means in accordance with the track shift signal. Tracking control means for controlling the light beam on the record carrier to be positioned on the track; and controlling the light beam between a position on the first information surface and a position on the second information surface of the record carrier. Focus jumping means for performing interlaced scanning between the first and second information surfaces of the record carrier when the information surface is intermittently scanned by the focus jumping means. A tracking position storage means for storing a desired target position of the tracking control means, and a target position of the tracking control means corresponding to an information plane to be jumped when the focus jumping means performs interlaced scanning. The system is provided with system control means for controlling the switching to the tracking position storage signal read from the tracking position storage means, so that the tracking is performed when moving from one information surface to the other information surface in a two-layer disc. By learning the position and switching the tracking position to the optimal value of each information surface stored at the time of focus jump according to the target information surface, a stable tracking control system can be established for any information surface. There are effects that can be built.

  According to the optical disc apparatus of the present invention, a converging means for converging and irradiating a light beam onto a record carrier having two information surfaces, and a convergence point of the light beam converged by the converging means are recorded. Moving means for moving in a direction substantially perpendicular to the direction of the track and the surface of the carrier, light detecting means for receiving reflected light from the record carrier in a plurality of divided areas, and each light receiving area of the light detecting means Phase difference track shift detecting means for generating a phase difference track shift signal corresponding to the positional relationship between the convergence point of the light beam on the information surface and the track, based on the phase relationship of the output signal of Tracking control means for driving the moving means in response to the output signal of the detection means and controlling the convergence point of the light beam on the record carrier to scan the track correctly; and Focus jumping means for performing interlaced scanning between a position on the first information surface and a position on the second information surface of the record carrier; and the record carrier when the information surface is skipped and scanned by the focus jumping means. The amount of advance or lag of the signal in each light receiving area of the light detecting means so that the output signal of the phase difference track deviation detecting means on the first information surface and the second information surface becomes a desired output. And a phase canceling amount storing means for storing the delay time or advancing amount of a signal in each light receiving area of the light detecting means when performing interlaced scanning by the focus jumping means. System control means for controlling switching to the phase cancellation amount storage signal read from the cancellation amount storage means. Therefore, even when moving from L0 to L1 or from L1 to L0 on a two-layer disc, when performing a focus jump according to the target information surface, the focus offset correction value corresponding to the information surface of the target layer By setting to, the offset of the tracking control system can always be removed, and there is an effect that stable tracking control can be constructed.

As described above, according to the optical disk device of the present invention,
1) Focus control can be stably drawn in disks having different substrate thicknesses such as DVDs and CDs.
2) Focus can be stably drawn in a two-layer disc or a multi-layer disc.
3) In a two-layer disc or a multi-layer disc, it is possible to quickly and accurately move to a desired information surface.
4) By generating the focus shift signal by holding the peak of the focus signal, it is possible to reduce the defocus associated with the track cross during the search and realize a stable search.
5) On each information plane, a correction value of the phase difference TE of the control system, a correction value such as an offset, a gain, and an eccentricity are learned, the correction value is calculated, and the information plane is moved every time the information plane is moved. By switching to the corresponding learning value, stable focus and tracking performance can be realized on any information surface.
Therefore, a highly reliable device corresponding to a large-capacity multilayer disc can be provided.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an optical recording / reproducing apparatus of the present invention, which is common to all embodiments 1 to 14 described below.

1) Configuration of the optical disc apparatus of the present invention As shown in FIG. 1, an optical system for irradiating the disc 101 as a recording medium with light beams 107a and 107b, that is, a light source 108 such as a semiconductor laser and a coupling lens 109. An optical system including a polarization beam splitter 110, a hologram element 106, a converging lens 105, and a disk motor 102 for rotating the disk 101 at a predetermined rotation speed is provided. The light beam generated by the light source 108 is converted into parallel light by the coupling lens 109. The parallel light is then reflected by the polarizing beam splitter 110, passes through the hologram element 106, is split into two light beams, is converged by the converging lens 105, and is focused on two focus points 107a and 107b in the thickness direction of the disk. Is formed as a bifocal light beam spot.

  Each of the light beam spots 107a and 107b irradiates the disk 101 rotated by the disk motor 102. These two light beams are selectively used depending on the substrate thickness of the disk to be mounted. For example, in the case of a disc with a thickness of 1.2 mm such as a CD, the light beam 107b is focused on the information surface, and in the case of a disc with a base material thickness of 0.6 mm with high density such as a DVD, Focus control of the light beam 107a is performed on the information surface.

  The disc used in the recording / reproducing apparatus according to the present invention has a single-sided information surface as shown in FIG. 6 (a) in addition to a single-layer disc having a single reproduction surface such as a conventional CD. As shown in FIG. 6 (b), a two-layer disc in which a transparent film is bonded in a sandwich with an adhesive layer of 20 to 60 μm, or an N-layer disc in which several μm film-like recording / reproducing films are stacked and stuck as shown in FIG. In the drawing, there is N = 4).

  The recording / reproducing apparatus further includes a condenser lens 111 and a four-divided photodetector 113 as elements for receiving the reflected light from the disk 101. The reflected light from the disk 101 passes through a converging lens 105, a hologram element 106, and a polarizing beam splitter 110, and is input to a four-divided photodetector 113 via a condenser lens 111, where a DSP 129 and an AD converter are provided. The signals are input to a focus control device FC and a tracking control device TC, each of which is constituted by 123 and 124, gain switching circuits 121 and 122, and the like.

  The tracking control device TC includes a four-divided photodetector 113, preamplifiers 114a, 114b, 115a, 115b, adders 116, 117, comparators 118, 119, a phase comparator 134, a differential amplifier 120, a gain switching circuit 122, It comprises a DSP 129, an AD converter 124, a drive circuit 130, and a tracking actuator 103. The light beam input to the four-divided photodetector 113 is converted into an electric signal (current), and voltage-converted and amplified by preamplifiers 114a and 114b and 115a and 115b. Each of the amplified signals is synthesized by the adder circuits 116 and 117 for each diagonal position, binarized by comparators 118 and 119, and phase-compared by the phase comparator 134. The phase-compared signal is input to the differential amplifier 120 while blocking the high band. The output of the differential amplifier 120 is obtained by comparing the phase of the data portion on the disk 101 of the light beam irradiated on the photodetector 113 and calculating the amount of deviation of the light beam spot from the track on the disk 101. It is well known that the signal is shown, and the output of the differential amplifier 120 is a track shift signal (TE; Track Error signal) by a phase difference method for controlling the light beam to scan the track correctly. .

  As a method for detecting such a track shift signal TE, there are a push-pull method, a three-beam method, and the like in addition to the above-described phase difference method. However, the present invention can be used with any detection method. It is not limited at all.

  The track shift signal TE is adjusted to a predetermined amplitude (gain) by the gain switching circuit 122. After that, it is converted into a digital value by the AD converter 124 and input to the DSP 129.

  On the other hand, the focus control device includes a photodetector 113 having a four-divided structure, preamplifiers 114a, 114b, 115a, 115b, adders 116, 117, a differential amplifier 133, a gain switching circuit 121, an AD converter 123, a DSP 129, and a driving circuit. 131 and a focus actuator 104.

  The output signals of the light receiving sections A to D of the four-divided photodetector 113 are subjected to current-voltage conversion and amplification by preamplifiers 114a and 114b and 115a and 115b, respectively. After being combined at 117, it is input to the differential amplifier 133.

  It is well known that the output of the differential amplifier 133 is a signal indicating the amount of defocus of the light beam spot on the information surface of the disk 101 of the light beam irradiated on the photodetector 113. The output of 133 is a focus shift signal (FE) by a so-called astigmatism method for controlling the light beam to be in a predetermined convergence state on the information surface on the disk 101. Here, as a method of detecting the focus shift signal FE, there are a knife edge method, an SSD method (Spot Sized Detection method), and the like, in addition to the astigmatism method. It is not limited at all.

  The focus shift signal FE is adjusted to a predetermined amplitude (gain) by the gain switching circuit 121 by changing the amplitude according to the light beam amount corresponding to the reflectance of the disk 101 and the like. After that, it is converted into a digital value by the AD converter 123 and input to the DSP 129.

  FIG. 2 is a block diagram showing in detail the focus control and focus pull-in portions in the DSP 129. Hereinafter, a description will be given by adding FIG. 2 to FIG.

  The DSP 129 forms a digital control system internally and includes a switch 201, a phase compensation filter 202, a gain switching unit 203, a switch 204, an S-shaped detection unit 205, a level determination unit 206, a waveform generation unit 207, and a hold unit 208. Is done.

  The FE digitally converted by the AD converter 123 is input to a phase compensation filter 202 including an adder, a multiplier, and a delay unit via a switch 201 that opens and closes a loop of a focus control system. The FE whose phase delay of the focus control system has been compensated for by the phase compensation filter is input to the switch 204 via the gain switching unit 203 for switching and setting the loop gain of the focus control system. The switch 204 opens and closes a loop of a control system, and further moves the converging lens 105 toward and away from the disk 101 when pulling in the focus control. 209 is applied to a drive circuit 131 for driving the focus actuator 104. The focus shift signal FE that has passed through the switch 204 during the focus control operation is converted into an analog signal via the DA converter 209 and input to the drive circuit 131. The drive circuit 131 appropriately drives the focus actuator 104 by current amplification and level conversion of the focus shift signal FE. In this way, the focus actuator 104 is driven such that the light beam on the disk 101 always has a predetermined convergence state.

  At the time of focusing, the waveform generating unit 207 outputs a triangular UP / DOWN signal, turns on the switches B and C of the switch 204, and drives the focus actuator 104 via the DA converter 209 and the driving circuit 131. Then, the convergent lens 105 is moved up and down to approach and separate from the disk 101.

  To explain further with reference to FIG. 2, the focus shift signal FE after AD conversion is branched in the DSP 129 to implement a focus pull-in learning operation. The disk 101 is rotated, the semiconductor 108 emits light, and an UP / DOWN signal is output from the waveform generator 207 to move the converging lens 105 closer to or away from the disk. At this time, the S-curve detection unit 205 measures the amplitude of the S-curve signal appearing on the defocus signal FE at the time of approaching or moving away from the focus deviation signal FE branched after the AD conversion, and the measured amplitude is larger than a predetermined amplitude. If it is smaller, the gain switching circuit 122 is controlled to set the gain to be lower. If the amplitude is larger than the predetermined amplitude, the gain switching circuit 122 is controlled and the gain is set to be high, so that the output from the AD converter 124 can make the S-shaped signal a constant amplitude. The focus shift signal FE in which the S-shaped signal has a predetermined amplitude by the S-shaped detection unit 205 and the gain switching circuit 122 is input to the level determination unit 206. The input focus shift signal FE is compared with a predetermined amplitude level (pull-in level) by the level judging unit 206. After detecting this pull-in level, the switch 201 is turned on and the switch 204 between A and C is turned on. Close the control loop to achieve the retraction action.

2) Focus pull-in method in the present invention The focus pull-in method in the optical recording / reproducing apparatus according to the present invention will be described in detail. For simplicity of explanation, a CD having a substrate thickness of 1.2 mm and a DVD-ROM disk having a thickness of 0.6 mm will be described as examples of a disk having a thin substrate.

  As described above, the optical recording / reproducing apparatus according to the present invention ensures mutual compatibility between a disc having a 1.2 mm base such as a CD and a disc having a 0.6 mm base such as a DVD. For this purpose, as described above, the light beam is split into two by the hologram element 106, and the two light beam spots are focused on each disk. Therefore, when the converging lens 105, that is, each light beam spot is moved toward and away from the disk 101 at the time of pull-in, an S-shaped signal is detected on the defocus signal FE each time the two light beam spots pass through the information surface of the disk. Is done. That is, as shown in FIG. 3, an S-shaped signal is generated by a light beam for a CD having a substrate thickness of 1.2 mm and a light beam for a DVD having a substrate thickness of 0.6 mm.

  By the way, since the light beam spot of a CD (CD beam) forms an image farther (upward) than the light beam spot of a DVD (DVD beam), as shown in FIG. The first S-shaped character that appears when the disk is moved closer is the focus of the CD beam, and as shown in FIG. The DVD beam is focused.

  Therefore, when a CD is loaded into the apparatus, the lens is once separated from the disk with reference to the mechanical neutral point, and the CD beam spot is moved far enough from the disk to approach the disk first. If the appearing S-shape is detected, the CD beam can be focused on the information surface of the CD. Further, when the DVD is loaded, the lens is once approached, and the spot of the DVD beam is moved away from the state where the spot is too far with respect to the disk. A DVD beam can be focused on the information surface.

  Actually, since both CDs and DVDs have a diameter of 120 mm, it is difficult to discriminate both disks. Therefore, as shown in FIG. 4, for example, the convergent lens is moved away from the initial position O to the point A once, and then approached, and the S-shaped amplitude Pc or AS (the total light amount signal) which first appears in the FE at the point B , That is, the sum of the signals of the adders 116 and 117), the CD or DVD is determined based on the signal amplitude that appears first. Thereafter, in the case of a DVD, after reaching the closest point, it is separated again and the first S-shaped signal QD appearing at that time reaches a predetermined level LVL1. Bring in control. In the case of a CD, after reaching the closest approach point D, it passes through the point E, moves to the farthest point F again, approaches again from the point F, and the first S character Rc that appears at that time is a predetermined value. At the point G where the information surface of the CD is detected when the level LVL2 has been reached.

  With the above configuration, focus control can be performed at high speed and stably both in the case of a DVD having a base of 0.6 mm and in the case of a CD having a base of 1.2 mm.

This specific pull-in procedure will be described in more detail with reference to FIGS. 4 (a), 4 (b) and 5.
FIG. 5 is a flowchart showing the procedure of the focus pull-in process. As shown in FIG. 5, when the power of the recording / reproducing device is turned on, the motor 102 rotates, and when the disk 101 reaches a predetermined rotation, The light source of the semiconductor laser 108 emits light.

  Then, a triangular wave signal for UP / DOWN the lens is output from the waveform generation unit 207, and the convergent lens 105 is moved to the farthest point in FIG. 4 by the drive circuit 131 and the focus actuator 104 via the switch 204 and the DA converter 209. It is lowered to a certain A (step S1).

  When the converging lens 105 reaches the farthest point A, the converging lens 105 is moved up so as to approach the disk 101 (step S2), and the FE signal at that time is sampled (step S3). As shown in FIG. 4, as the convergent lens 105 gradually increases, the convergence point of the CD light beam 107b far from the lens reaches the information surface of the disc at point B. Since an S-shaped PC due to the CD beam appears, the amplitude of the S-shaped PC is measured (step S4).

  Here, as a method of measuring the amplitude of the S-shaped PC, for example, the FE is continuously sampled, the MAX value or the MIN value is obtained while comparing the respective sampled values, and the amplitude is calculated from the MAX value or the MIN value. It can be achieved in the manner required.

  If the amplitude measurement of the S-shaped PC has not been completed, the convergent lens 105 is further driven to approach the disk 101 (N in step S5).

  When the amplitude measurement of the S-shaped PC is completed (Y in step S5), the lens UP is continued up to the closest point D (step S6). During this time, the convergence point of the lower DVD beam 107a also crosses the information plane, and the corresponding S-shaped PD appears on the FE, so that the amplitude measurement is performed similarly (steps S7 and S8). Then, after the converging lens is brought close to the closest point D (Steps S9 and S10), the measured values of the S-shaped PC and PD by the CD beam and the DVD beam are compared, and whether the loaded disc is a CD or a DVD is determined. Is determined (step S11).

  When the converging lens 105 is moved away from the disk 101 after reaching the closest approach point D, the convergent point of the lower DVD beam 107a crosses the information surface first. Appears in Next, the convergence point of the upper CD beam 107b crosses the information surface, and an S-shape corresponding thereto appears on the FE.

  Therefore, when it is determined that the DVD is a DVD, it is detected that the S-shaped QD appearing first after being separated from the closest point D has reached the predetermined pull-in level LVL1 as shown in FIG. Operate (steps S19, S20, S21, S22, S23).

  If it is determined to be a CD, as shown in FIG. 4B, it moves from the closest point D to the farthest point F and ignores the S-character appearing during that time (steps S12 and S13). Then, it is detected that the S-shaped RC first appearing after approaching the disk again from the farthest point F has reached the predetermined pull-in level LVL2, and the focus control is operated (steps S14, S15, S16, S17, S18). .

  By configuring and operating as described above, the pull-in operation of the focus control of DVD and CD can be realized.

3) Focusing method for pulling in a two-layer, multi-layer disc, drawing-in method FIG. 6 is a cross-sectional view of a DVD two-layer disc having a 0.6 mm substrate bonded thereto, and a cross-section of a multi-layer disc in which thin film-like signal films are multiply laminated. The figure is shown. The procedure for pulling the focus to such a two-layer disc and a multi-layer disc will be described using a two-layer disc as an example.

  FIG. 7 shows the FE, the drive signal of the focus actuator, and the drive signal of the lens and the disk when the lens approaches and separates from the two-layer disk having the information surface of the two-layered disk having the two-layered 0.6 mm substrate. FIG. 4 is a waveform diagram showing relative positions. At this time, as shown in FIG. 7, two continuous S-shaped signals (a double S-shaped signal, for example, P1) are provided on the FE signal obtained through the differential amplifier 133 or the gain switching unit 121 and the AD converter 123 therefrom. , P2), learning is performed so that the amplitude of each of the double S-shaped signals is constant, and a predetermined level near the zero cross, which is the focus point, is detected, and the focus control is performed.

  FIG. 8 is a waveform diagram showing the relationship between the FE at the time of actual focus pull-in, the RF signal corresponding to the reflected light amount sum, and the UP / DOWN signal output from the waveform generation unit 207, that is, the focus drive signal. The same alphabet is written in the same position as 7. FIG. 9 is a flowchart showing the flow of the focus learning pull-in procedure realized by the DSP 129.

  To explain further with reference to FIG. 2, in the above-described two-layer disc, similarly to the one-layer disc, the FE after AD conversion is branched in the DSP 129 to realize the focus pull-in learning operation. The disk 101 is rotated, the semiconductor laser 108 emits light, and an UP / DOWN signal is output from the waveform generator 207 to move the converging lens 105 closer to or away from the disk 101. At this time, the FE branched after the A / D conversion is measured by the S-shaped detecting unit 205 to measure the amplitude of the S-shaped signal appearing on the FE at the time of approaching or separating, and if the measured amplitude is smaller than the predetermined amplitude, the gain switching circuit is used. 121 is set so that the gain becomes low. If the amplitude is larger than the predetermined amplitude, the gain switching circuit 121 is controlled to set the gain to be higher, so that the S-shaped signal can have a constant amplitude at the output after the AD converter 123. The FE in which the S-shaped signal has a predetermined amplitude by the S-shaped detection unit 205 and the gain switching circuit 121 is input to the level determination unit 206. The input FE is compared with a predetermined amplitude level (pull-in level) by the level determination unit 206, and after detecting this pull-in level, the switch 201 is turned on, and the switch 204 between A and C is turned on to perform focus control. Close the loop to achieve retraction.

  The waveform generation unit 207 generates an acceleration / deceleration pulse when moving from the first layer to the second layer and from the second layer to the first layer, for example, in a two-layer disc. The embodiment will be described in detail.

  The relationship between the FE at the time of focus pull-in and the UP / DOWN signal output from the waveform generation unit 207 is as shown in FIG. 7, and a flowchart showing the flow of the focus pull-in procedure realized by the DSP 129 according to this relationship. This is shown in FIG. 9 and will be further described with reference to FIG.

  When the power of the recording / reproducing apparatus is turned on, the motor 102 rotates, and when the disk 101 reaches a predetermined rotation, the light source 1 of the semiconductor laser emits light and the focusing operation starts.

  In FIG. 9, in step S 1, a triangular wave signal for UP / DOWN the lens is output from the waveform generation unit 207, and the converging lens 105 is controlled by the drive circuit 131 and the focus actuator 104 via the switch 204 and the DA converter 209. It is raised to H which is the closest point in FIGS. At this time, the convergence point of the light beam 105a is located above the recording / reproducing surface L1 of the second layer on the disk.

  When the convergent lens 105 reaches the closest point H, the convergence lens 105 is DOWN so as to be separated from the disk 101 (step S2), and the FE signal at that time is sampled (step S3). As shown in FIG. 7, when the converging lens 105 gradually descends, the convergence point of the light beam 107a close to the lens reaches the second layer L1 of the recording / reproducing surface of the disk at the point I, and this I Near the point, an S-shaped character Q2 corresponding to the L1 plane appears (step S4).

  Here, there are various methods for measuring the amplitude of the S-shaped Q2. For example, the FE is continuously sampled, the MAX value or the MIN value is obtained while comparing the respective sampled values, and the MAX value is obtained. , Or a method of obtaining the amplitude from the MIN value can be easily realized. In order to prevent the accuracy of the sampling FE from deteriorating due to circuit noise or noise due to an address portion or scratches preformatted on the disk, a digital low-pass filter is applied to the sampled FE by software processing of the DSP 129. If it is configured and the MAX value and the MIN value are obtained from the values passed through the digital filter, the amplitude can be measured with high accuracy (step S4).

  When the measurement of the amplitude of the S character Q2 is completed (Y in step S5), the lens DOWN is continued (step S6), and the FE is sampled (step S7). Since the distance between the second layer L1 and the first layer L0 is about 40 microns, it immediately reaches the point J of L0 on the recording / reproducing surface after passing through the point I of L1. In the vicinity of the point J, the S-shaped character Q1 corresponding to the amount of light there appears, so the measurement of the S-shaped character Q1 is performed in the same manner as the measurement of the S-shaped character Q2 (step S8).

  When the amplitude measurement of the S character Q1 is completed (Y in step S9), the lens DOWN is continued up to the farthest point E (step S10). During this time, the convergence point of the upper light beam 107b crosses the recording / reproducing surface, so that the corresponding S-shape appears on the FE. In particular, in the case where the surface runout is large, the light beams 107a and 107b almost simultaneously detect the recording / reproducing surface, and as a result, the two S-characters interfere with each other to form a nonlinear S-shape. The part is ignored and DOWN is performed to the farthest point A (steps S10 and S11).

  After reaching the farthest point A, the converging lens 105 is moved closer to the disk 101 from the farthest point A again. First, the convergence point of the upper light beam 107b crosses the recording / reproducing surface. The corresponding S-shape appears on the FE. In particular, in the case of large surface deviation, the light beams 107a and 107b detect the recording / reproducing surface almost at the same time, and the two S-characters interfere with each other to form a non-linear S-shape. Therefore, it is difficult to accurately detect the information planes L0 and L1. Therefore, at the time of UP, the S-character detection processing is particularly omitted, and the converging lens 105 is quickly raised again to the closest approach point H (step S12). At that time, an appropriate focus gain is calculated for each layer from the amplitude value of the S-shaped Q2 of the second layer and the amplitude value of the S-shaped Q1 of the first layer measured at the time of the previous lens DOWN. The set value is stored in a RAM (not shown) in the DSP 129. Further, the S-shaped amplitude at the time when the gain value is changed is calculated, and a value of 10 to 30% of the amplitude is set as the pull-in level. The calculated pull-in levels of the first layer L0 and the second layer L1 are also stored in the RAM in the DSP 129 in the same manner as the S-shaped amplitude described above (steps S13 and S14).

  Thereafter, when the converging lens 105 is lowered from the closest point E, the light beam 105a sets the focus gain value and the pull-in level corresponding to the second layer L1 detected first by the gain switching unit 122 and the level determination unit. 207 is set (steps S15 and S16). After the setting, the convergence lens 105 is set to DOWN (step S17), FE is sampled (step S18), and the set pull-in level and FE are compared. When the pull-in level is reached or exceeded, it is determined that the pull-in level has been detected (step S19), the UP / DOWN signal is stopped (step S20), the lens descent is stopped, and FCON, that is, the switch 201 is turned on and the switch 201 is turned on. By turning on between A and C of 204 and closing the focus loop (step S21), the focus is pulled in.

  As described above, after always focusing on the information surface L1 where the convergence point of the light beam arrives first, the optical beam moves to the adjacent predetermined recording / reproducing surface, and the signal recording / reproducing is performed. The method of moving between the layers will be described later in the first embodiment.

  Further, as described above, the S-shaped signals corresponding to L0 and L1 are measured in steps 13 and 14, the set value of the gain switching unit 122 corresponding to the amplitude value is stored in the RAM, and the set value is switched. The pull-in level of the L0 and L1 layers at a predetermined amplitude is calculated. The stored gain setting values of L0 and L1 are respectively set for target information surfaces during focus jumping. Also, in addition to the amplitude of the S-shaped signal, the set value of the gain switching unit can be similarly obtained by measuring the amplitude of a signal such as AS or RF proportional to the amount of reflected light. The maintenance will be described in detail in the second and third embodiments.

  In this way, in this pull-in method, the UP is once moved from the mechanical neutral point to the closest point H, then separated to the farthest point A, the S-shaped amplitude is measured, and learning such as gain is executed. The UP is performed again to the closest point H, and the S-shape of the information surface L1 appearing first after being separated from the closest point H is detected, and the focus control is always drawn to the information surface L1.

  Here, based on the mechanical neutral point, a DOWN is once made to the furthest point A, and an S-character appearing on the FE when the UP is made from the point A to the closest point H is detected to learn the gain. If the S-shaped information surface L1 that appears first when the information surface L1 is separated from the closest approach point H by DOWN is detected and the focus control is drawn into the information surface L1, the time required for the pull-in can be reduced. Can be.

  As described above, in the case of a two-layer or multi-layer disc, the information surface is always drawn to the information surface farthest from the converging lens. By performing the movement, the focus can be stably pulled in, and it is possible to move to a desired information surface.

  By using the pull-in method described above, even if a two-layer or multi-layer disc having a different base material thickness is mounted in a bifocal optical recording / reproducing apparatus corresponding to a disc having a different base material thickness, it is possible to cope with each. By accurately detecting and measuring the S-shape with the upper and lower light beams, switching the gain, and performing the pull-in level learning, the pull-in can be reliably performed on the first detected recording / reproducing surface.

Embodiment 1 FIG .
Next, in the optical disc device according to the first embodiment of the present invention, focus jumping operation for moving from one information surface to another information surface will be described with reference to FIGS. 1, 2, and 10 to 12, 18, and 23. This will be described with reference to FIG. Here, a description will be given using a two-layer disc having two layers of information surfaces, particularly L0 and L1. However, it is clear that the present embodiment can be applied to a disc having two or more information surfaces, and the description of the disk having two information surfaces is not limited at all.

  FIG. 10 is a block diagram showing in detail the tracking control part in the DSP 129 of FIG. FIG. 4 is a waveform diagram showing a positive and negative pulse-like signal FEJMP pulse and a TE signal applied to a focus control system.

  Further, FIG. 18 is a waveform diagram showing the relationship between the relative position between the disc and the converging lens (light beam) when the focus jump is performed from L0 to L1 in FIG. 11, and the relationship between the FE signal and the focus jump pulse signal FEJMP. (A) and (b) show detection spots detected by the photodetector when the FE signal is at points A, B, C, D, E, F, G, H, and I in FIG. ), (C), (d), (e), (f), (g), (h), and (i).

First, the basic operation of the first embodiment will be described with reference to FIG.
As shown in FIG. 18, when the converging lens is moved closer to the two-layer disc, the focal point of the light beam passes through the information planes L0 and L1, and at that time, the FE signal includes a two-period sinusoidal S-shaped signal. appear.

  Here, the reflectances of L0 and L1 are desirably designed so that L0 and L1 are about 30% and L1 is about 70%, and the return light amounts from L0 and L1 are almost equal to make the performance equal. . The distance between L0 and L1 is about 40 μm, and the range in which the S-shaped signal appears is larger than the range of 7 to 10 μm above and below each information plane, so that the signal is generated by the reflected light from each information plane. S-shaped signals are not affected by the amount of reflected light from other information surfaces.

  As the focal point of the light beam approaches L0, the amount of reflected light from L0 increases, so that the FE increases in amplitude from the substantially zero level (point A) to -polarity, and peaks at point B- When the amplitude of the polarity decreases and approaches the 0 level again and reaches the 0 level (point C), the focal point of the light beam is located on the information plane L0. As the focal point of the light beam moves away from L0, the amplitude increases to + polarity, the peak of point C decreases, the amplitude of + polarity decreases, and returns to 0 level.

  When the light further passes through L0 and approaches the L1 layer, the reflected light from L1 increases as in the case of L0. Therefore, the amplitude of the FE increases from the substantially zero level (point E) to the negative polarity. , F, the amplitude of the negative polarity decreases and approaches the 0 level again. When the level reaches the 0 level (point G), the focal point of the light beam is located on the information plane L1. When the focal point of the light beam moves away from L1, the amplitude increases to + polarity, the peak at point H decreases, and the amplitude of + polarity returns to 0 level. As described above, when the focal point of the light beam passes through L0 and L1, a two-cycle S-shaped signal as shown in FIG. 18 appears.

  When focus jumping is performed from L0 to L1, the tracking control is turned off and the focus control is held, and a pulse-like acceleration pulse and deceleration pulse signal as shown in FIG. 18 is applied to the focus control system. For example, when the focus control is operating so as to follow the information surface of L0 (the position of the point C), the focus control is held, and an acceleration signal having a predetermined amplitude value of + polarity is output for a time t. Apply. The light beam starts moving from the information surface L0 toward the information surface L1 by the acceleration signal. Even if the acceleration signal is set to 0 before reaching L1, the light beam moves to L1 due to inertial force. As described above, at this time, the FE signal includes S-shaped signals on the + side of L0 and on the-side of L1 (the S-shaped signals between points D and E and the S-shaped signals between points E and F, respectively). Reach L1.

  At this time, a point E at which the S-shape becomes almost 0 between L0 and L1 so that the moving speed of the light beam at the time of reaching the information surface L1 is sufficiently reduced and the focus control is re-operated stably. , That is, at a position substantially intermediate between the information planes L0 and L1, a point G at which the light beam reaches L1 or a point R0 at which the light beam has passed through a deceleration signal having a predetermined amplitude value having a negative polarity opposite to the acceleration signal. Apply to the point and reduce the moving speed of the light beam. Note that the amplitude of the FE S-shaped signal fluctuates near the point E due to the influence of the disk runout and the like. The deceleration pulse is set to 0 at the timing when the pull-in level is detected, and the focus control is quickly performed. As a result, the light beam follows the information plane L1 (the position of the point G), and the focus jump is completed. Therefore, as shown in FIG. 11, when the acceleration and deceleration signals are applied with their polarities switched, it is possible to stably move from L0 to L1 and from L1 to L0.

  FIG. 12 is a flowchart showing a more detailed flow of the focus jumping process realized by the DSP 122. Hereinafter, description will be made with reference to FIGS.

  When moving from the first layer L0 to the second layer L1, or when moving from the second layer L1 to the first layer L2, processing by software in the DSP 122 is performed in the same manner as the focus pull-in processing described above. Accordingly, the waveform generation unit 207 applies a pulse-like signal FOJMP to the control system, and realizes this by a focus jumping operation of jumping from the information surface to the information surface.

  For example, when moving from L0 to L1, at step S1 in FIG. 12, the switch 301 in FIG. 10 is turned off to turn off tracking control (TROF), and at step S2, the switch 204 between B and C in FIG. Is turned on, and the HOLD unit 208 holds the focus drive signal (FO drive hold).

  Next, in step S3, an acceleration pulse A0 of a jumping pulse (FEJMP pulse) is generated in the waveform generation unit 207 in FIG. 2, and the focus actuator 104 is transmitted through the switch 204 in FIG. Is applied. The pulse width and crest value of the applied acceleration pulse are set according to the sensitivity of the focus actuator 104 and the acceleration of the disk 101. When a predetermined pulse is applied to the focus control system, the converging lens 105 starts to move upward, that is, in the direction of L1, and accordingly, the FE signal appears as an S-shaped signal as shown on the left side of FIG. Come.

  In step S4, when the S-shaped signal reaches the reference level 0, that is, when the zero crossing of the FE (or the amplitude level in the vicinity thereof) is detected, the gain setting value of the gain switching circuit 122 is set to L1 in steps S5 and S6. The state is switched to a state, and the focus pull-in level set by the level determination unit 206 is set to the L1 pull-in level. As a result, the L-shaped S-shaped signal and the pull-in level can be correctly detected. Further, in step S7, the deceleration pulse B0 generated by the waveform generator 207 is applied in the same manner as the acceleration pulse. With this deceleration pulse, a brake is applied to the convergent lens moving in the L1 direction, and when the FE signal reaches the pull-in level R0 of L1 (when Y in step S8), the convergent lens is just moved. The speed is at a minimum (close to 0). At this time, the output of the deceleration pulse is stopped, and the switch 204 in FIG. 2 is immediately switched to an ON state between A and C (drive hold OFF) to bring the focus control into an operating state (FO control ON). In the vicinity of the pull-in level R0 point, the focus can be pulled in stably (steps S8 and S9). Thereafter, in the section up to U0 in FIG. 11, it is confirmed from the output of the TE signal (or the RF signal) that the output has exceeded a predetermined value, and that the focus has been normally drawn (steps S10 and S11). . Finally, in step S12, at a point U0 in FIG. 11, the switch 301 in FIG. 10 is turned on to activate the tracking control, search for a predetermined track and sector address, and end the processing.

  Also, it has been described that the constant time t is set as the time width of the acceleration pulse, and the time width from almost the middle of L0 to L1 to reach L1 is set as the time width of the deceleration pulse. May be as follows. That is, the amplitude of the S-shape is stored in the RAM in the form of its maximum value and minimum value, and the level of the predetermined ratio of the maximum value and the minimum value (approximately 60% to 80% is appropriate) is determined by the comparator level. The maximum value and the minimum value of the S-shape are detected by the fact that the FE signal being sampled becomes smaller after becoming larger than the comparator level or becomes smaller after being smaller. When the maximum value is detected, the acceleration pulse is stopped and the deceleration pulse is output, and when the minimum value is detected, the deceleration pulse is stopped and the focus control is operated. The timing can be freely switched by the set comparator level. In particular, the timing is appropriately advanced within the range of the performance of the focus actuator 104. More, it is possible to greatly reduce the influence of the positional deviation due to wobbling, it is possible to further perform high-speed movement.

  As described above, according to the first embodiment, in a state where the focus control is held by the focus jumping means, the acceleration signal or the deceleration signal having different polarities is applied to the converging lens driving means, and the light beam is formed into two layers. Of the FE signal, that is, the output of the light beam convergence state detecting means, and detects whether the light beam has reached or slightly passed the target information surface. By doing so, the movement of each information surface of the two-layer or multilayer disc can be performed at high speed and stably.

Embodiment 2 FIG .
Next, the optical disc device according to the second embodiment of the present invention is designed to allow focus jumping to operate stably with respect to variations in discs and the like. The configuration for that and the operation will be described below. .

  As described above, it is desirable to control the reflectivity of L0 and L1 so that the amount of return light from L0 and L1 is substantially equal. Actually, the amount of return light from L0 and L1 varies due to the variation of the intermediate layer between them. This variation in the amount of returned light appears directly as a variation in the FE signal, the AS signal, or the RF signal.

  If the amplitude of the FE signal fluctuates, the gain of the focus control system will fluctuate when the information plane is moved by a focus jump, and if the pull-in becomes unstable or the dispersion increases, the signal will pass through the target information plane. This makes it impossible to perform stable movement because the pull-in level for detecting that the operation has been performed is erroneously detected or cannot be detected.

  Therefore, as shown in FIG. 8, the S-shaped amplitude values of the two FE signals corresponding to L0 and L1 that appear even when the focus is drawn on the dual-layer disc are measured, and L1 and L0 are determined based on the measured values. Then, the gain of the FE signal of the gain switching unit 121 in FIG. 2 is switched so as to have a predetermined amplitude. Further, the measured amplitude value or the set value of the gain switching unit 121 based on the measured value is stored in the RAM in the DSP 129 in FIG. 2, and when the focus jumping is performed, in steps S5 and S6 in FIG. Is switched to a set value based on the stored amplitude value of the S-shaped information surface. Further, the pull-in level of the focus control is set in the level determination unit 206 corresponding to the S-shaped amplitude of the FE signal after the gain switching.

  For example, if the thickness of the intermediate layer of the two-layer disc varies extremely, the amount of reflected light at L1 will be much lower than at L0. Accordingly, the S-shaped L0 has a substantially predetermined amplitude, and the amplitude of the S-shaped L1 is smaller than usual. The S-shaped amplitudes of L0 and L1 are measured and stored at the time of focusing, and a gain is set so that the stored S-shaped amplitude of L1 becomes a predetermined amplitude during focus jumping from L0 to L1. In step 2, the set gain of the gain switch 121 is increased.

  As described above, even if the amount of return light from each information surface of a two-layer or multilayer disc varies and the S-shaped amplitude of the FE signal changes, or the S-shaped amplitude or the like varies among discs, devices, and heads. Even if the amplitude value of each S-shaped signal of the FE signal or the set value of the gain switching unit 121 based on the amplitude is stored in the RAM in the DSP 129, the stored value is set when the focus jumping is operated. By doing so, pull-in can be performed sufficiently in response to this variation.

  Further, since the lens moving speed at the time of pulling in at the time of activation is different from the lens moving speed at the time of focus jumping (usually, the speed of focus jumping is higher than at the time of pulling in), the difference in the lens moving speed is determined. In consideration of this, the FE gain of the gain switch 121 is switched based on the S-shaped amplitude of the FE signal measured and stored when passing through each information surface at the time of startup, and after the switching, the amplitude becomes substantially a predetermined amplitude. For the S-shaped signal, the pull-in level at the time of focus jumping is set to a level different from the focus pull-in level at the time of activation. As a result, more stable retraction can be realized.

  As described above, according to the second embodiment, the moving means is driven so as to move the light beam away from or close to the record carrier to obtain the light beam when the light beam passes through the first and second information surfaces. Storage means for storing a signal for detecting the convergence state of the light beam on the record carrier, and when the focus jumping is performed by the focus jumping means, the gain of the focus control means is stored in the convergence state detection signal storage means. The focus control pull-in level at the time of the focus jumping is set in accordance with the output signal of the focus control means that has switched the gain. Variations in the amount of light returned from each information surface of a multi-layer or multi-layer disc, or S-shape fluctuations for each disc, device, and head Even for the variations in which the sufficiently corresponding, the focus jumping can be operated stably.

  Further, taking into account the lens speed at the start-up pull-in and the lens speed at the time of focus jumping, the pull-in level at the time of focus jumping is calculated based on the S-shaped amplitude of the FE signal stored at the start-up. If the level is provided independently, more stable pull-in can be realized.

Embodiment 3 FIG .
Next, as Embodiment 3 of the present invention, similarly to Embodiment 2, a configuration for stably operating focus jumping with respect to variations in disks and the like, and the operation thereof will be described.

  By the way, in practice, the variation in the amount of return light from L0 and L1 appears directly as the variation in the amplitude of the FE signal, the AS signal, or the RF signal. Is proportional to the amplitude of the FE signal. Therefore, the amplitude of the FE signal can be easily estimated from the amplitude of the AS signal, the RF signal, or the envelope detection signal thereof.

  Therefore, in the third embodiment, when the focus is pulled into the two-layer disc, two AS signals corresponding to L0 and L1 appearing in synchronization with the S-shaped signal of the FE signal (not shown, see FIG. 4) Alternatively, the amplitude of the S-shaped signal of the RF signal is measured, and the gain of the FE signal of the gain switching unit 121 in FIG. 2 is switched so as to have a predetermined amplitude at L1 and L0 based on each measured value. Further, the amplitude value of the FE estimated from the amplitude of the measured AS signal, the RF signal, or the envelope detection signal thereof, or the set value of the gain switching unit 121 based on the amplitude value is stored in the RAM in the DSP 129 in FIG. When the focus jumping is performed, the values are switched to the set values based on the stored S-shaped amplitude values of the respective information surfaces in steps S5 and S6 in FIG. Further, the pull-in level of the focus control is set according to the S-shaped amplitude of the FE signal after the gain switching.

  Further, by setting the pull-in level in accordance with the S-shaped amplitude of the FE signal after the gain switching, focus jumping can be operated stably as in the second embodiment.

  That is, even if the amount of return light from each information surface of a two-layer or multi-layer disk varies and the amplitude of the S-shape changes, or if the S-shape amplitude of each disk, device, or head varies, An AS or RF or RF envelope signal proportional to each S-shaped signal is measured, and the measured value or a set value of the gain switching unit 121 based on the measured value is stored in a RAM in the DSP 129, and the stored value is used as a focus jump. By setting this when the operation is performed, the pull-in can be performed sufficiently in response to this variation.

  Further, taking into account the lens speed at the start-up pull-in and the lens speed at the time of focus jumping, the pull-in level at the time of focus jumping is calculated based on the S-shaped amplitude of the FE signal stored at the start-up. If the level is provided independently, more stable pull-in can be realized.

  Further, the FE signal sampled at the time of focus jumping is converted into a signal obtained by dividing the FE signal by the sum of the outputs of the adders 116 and 117 in FIG. If the signal is always switched in accordance with the amplitude of the total light amount signal AS, even if the reflectivity at L1, L0 or the disc, at the middle, or at the outer periphery greatly varies, the information of the jump destination can be obtained more accurately. It is possible to detect the level of attraction of the surface.

  When moving from L1 to L0, the FE signal or the FEJMP pulse is as shown on the right side of FIG. Jumping can be realized.

  Further, in the above description, the control signal input to the D / A converter 209 in FIG. 2, that is, the drive signal of the FE is held and jumped. The FE signal input to the switch 201 in FIG. 2 is removed by a signal high-frequency rejection filter, the signal is held during jumping, and output from the D / A converter 209 to the drive circuit 131. A configuration may be adopted, and in this case, an unstable element due to a position error due to surface shake can be absorbed.

  As described above, according to the third embodiment, the moving means is driven so as to move the light beam away from or closer to the record carrier, and the light beam is obtained when the light beam passes through the first and second information surfaces. Convergence state detection signal storage means for storing a signal that has detected the convergence state of the light beam, and when the focus jumping is performed by the focus jumping means, the gain of the FE for switching the S-shaped amplitude is set to the convergence state detection signal storage means. Is set to a value based on the amplitude value of the FE estimated from the amplitude of the AS signal or the RF signal stored in the FE signal or its envelope detection signal, and the focus control pull-in level is set to the S-shaped amplitude of the FE signal after the gain switching. Correspondingly, the amount of return light from each information surface of a two-layer or multi-layer disc varies, and the S-shaped amplitude is set. Even changed respectively, also the disk or device, even though variations in S-curve amplitude, etc. of the FE signal every head, a stable focus jumping against this variation can be stably operated.

  Further, taking into account the lens speed at the time of pull-in at the time of starting and the lens speed at the time of focus jumping, the amplitude, the AS signal, the RF signal, or the envelope thereof measured and stored when passing through each information surface at the time of starting. If the gain is switched based on the amplitude of the detection signal, the value of the pull-in level at the time of focus jumping after the switching is calculated, and the pull-in level is provided independently, more stable pull-in can be realized. .

  Furthermore, the amplitude of the signal for detecting the convergence state of the light beam irradiated on the information surface is divided by the amplitude of the signal for detecting the amount of reflected light from the information surface, and the moving means is determined based on the result of the division. If the drive is performed to perform the jumping from the first information surface to the second information surface, the pull-in level of the information surface at the jump destination can be accurately obtained even if the reflectance at the inside, the middle, and the outer periphery of the disk varies greatly. Can be detected, and accurate focus jumping can be realized.

Embodiment 4 FIG .
The peak values of the acceleration pulse and the deceleration pulse at the time of performing the focus jumping as described above secure the stability of the focus jumping in consideration of the sensitivity of the focus actuator 104, surface shake, vibration from the outside, and the like. You need to be able to set it up.

  When the optical disk apparatus is of a horizontal installation type in which a disk is installed horizontally, the moving acceleration of the converging lens 105 is (when the moving direction of the converging lens 105 driven by the focus actuator 104 is + 1G (G is the gravitational acceleration), and when the acceleration direction is from above to below (the moving acceleration of the converging lens 105 driven by the focus actuator 104 is -1G), the moving speed of the converging lens is affected by the influence. Accordingly, the movement becomes slower when moving from below to above, and becomes faster when moving from above to below.

  Therefore, in order to cancel this difference and to realize a stable jumping operation, the fourth embodiment differs from the fourth embodiment in that the acceleration pulses A0 and A1 are moved from above to below (from L1 to L0). , The peak value is changed when moving from below to above (from L0 to L1). That is, the peak value of the acceleration pulse A0 in the case of movement from below to above (from L0 to L1) is made larger than the peak value of the acceleration pulse A1 in the case of movement from above to below (from L1 to L0). It was made.

  Further, instead of the peak value of the acceleration pulse, the setting of the time width of the acceleration pulse may be changed, and the time width of the acceleration pulse A0 in the case of moving from below to above (from L0 to L1) may be changed from above. It may be set to be longer than the time width of the acceleration pulse A1 in the case of moving downward (from L1 to L0).

  Also, instead of controlling the peak value or time width of the acceleration pulse alone, the product of the peak value and time width of the acceleration pulse is calculated by moving the product from below to above (from L0 to L1). (L1 to L0) may be set to be larger.

  In any of the above cases, if the difference in the movement acceleration when moving from below to above and from above to below is set to be approximately 2G, the focus jumping can be stabilized in any direction of movement. It is possible to secure the property.

  As described above, according to the fourth embodiment, the focus jumping means includes an acceleration means for generating an acceleration signal for moving the convergence point of the light beam from one information surface of the record carrier to the other information surface. And a deceleration means for decelerating the moving speed of the convergence point of the light beam, and when the record carrier surface is installed so as to be horizontal, the crest value and time of the acceleration signal at the time of moving from below to above. Make the value of the width product larger than that when moving from above to below, or the peak value of the acceleration signal when moving from below to above, or larger than that when moving from above to below, or from below. Since the time width of the acceleration signal when moving upward is longer than that when moving downward from above, there is an effect that the stability of focus jumping can be secured in any moving direction. .

Embodiment 5 FIG .
When the optical disk device is of the horizontal installation type, as in the fourth embodiment, the values of the deceleration pulse, not the peak value of the acceleration pulse, the time width, or the product of both, are set. Control may be performed, and the same effect as in the fourth embodiment can be obtained.

  That is, in the fifth embodiment, the respective deceleration pulses B0 and B1 have different waveforms when moving from above to below (from L1 to L0) and when moving from below to above (from L0 to L1). Try to change the highs. That is, the peak value of the deceleration pulse B0 when moving from below to above (from L0 to L1) is smaller than the peak value of the deceleration pulse B1 when moving from above to below (from L1 to L0). I do.

  Further, instead of the peak value of the deceleration pulse, the setting of the time width of the deceleration pulse may be changed, and the time width of the deceleration pulse B0 in the case of moving from below to above (from L0 to L1) may be changed from above. The time width of the deceleration pulse B1 in the case of moving downward (from L1 to L0) is set to be shorter than the time width.

  Also, instead of controlling the crest value or time width of the deceleration pulse independently, the product of the crest value of the deceleration pulse and the time width is not controlled from above when moving from below to above (from L0 to L1). It may be set to be smaller than in the case of moving downward (from L1 to 1L0).

  In any of the above cases, if the difference in the movement acceleration when moving from below to above and from above to below is set to be approximately 2G, the focus jumping can be stabilized in any direction of movement. It is possible to secure the property.

  As described above, according to the fifth embodiment, the focus jumping means is an acceleration means for generating an acceleration signal for moving the convergence point of the light beam from one information surface of the record carrier to the other information surface. And a deceleration means for decelerating the moving speed of the convergence point of the light beam, and when the record carrier surface is installed so as to be horizontal, the peak value of the deceleration signal when moving from below to above and The value of the product of the time width is smaller than that when moving from upper to lower, or the peak value of the deceleration signal when moving from lower to upper is smaller than that when moving from upper to lower, or lower. Since the time width of the deceleration signal when moving upward from is shorter than that when moving downward from above, it is possible to ensure the stability of focus jumping in any moving direction. is there

Embodiment 6 FIG .
The optical disk device according to the sixth embodiment relates to a device that has both a horizontal and vertical installation type, that is, a type having both a mechanism for horizontally installing a disk and a mechanism for vertically installing a disk, and focus control ON (FO). The DC component of the drive current of the focus actuator 104 after the control ON), that is, the DC value of the input portion of the DA converter 209 is detected, and it is determined whether the disk is horizontally or vertically installed according to the magnitude of this value. According to the result of the determination, the acceleration pulse and the deceleration pulse are configured to be switched to the respective optimum values in the respective installation states. This makes it possible to stably achieve focus jumping even when the disk has large surface runout or when there is no margin in focus actuator sensitivity and the like.

  In this case, when it is determined that the disk is set horizontally, for example, the acceleration pulse and the deceleration pulse may be set to the set values described in the fourth and fifth embodiments. On the other hand, when it is determined that the disk is set vertically, the moving speed of the acceleration pulse and deceleration pulse when moving from L0 to L1, and the moving speed of the acceleration pulse and deceleration pulse when moving from L1 to L0 In this case, the effect of the gravitational acceleration of + G when moving from L0 to L1 and the gravitational acceleration of -G when moving from L1 to L0 are compared with the case of horizontal installation. Therefore, the moving speed from top to bottom in horizontal installation is faster than the movement speed in vertical installation, and the moving speed from bottom to top in horizontal installation is faster than the movement speed in vertical installation. Become slow.

  Therefore, in order to cancel this difference and realize a stable jumping operation, the acceleration pulses A0V and A0H in the case of the vertical installation and the horizontal installation are changed to the peak value in the case of moving from below to above (from L0 to L1). , Or change the time span.

  That is, the product of the peak value of the acceleration pulse A0H and the time width in the case of the movement from the bottom to the top (from L0 to L1) in the horizontal installation is determined by the product of the vertical installation (the movement from L0 to L1 is also L1). The same applies to the movement from L0 to L0), which is larger than the product of the peak value of the acceleration pulse A0V and the time width.

  Alternatively, the acceleration pulse of horizontal installation and vertical installation, the time width is constant, and only the peak value is moved from below to above (L0 to L1) in horizontal installation. When moving from L1 to L0, the acceleration pulse for horizontal installation and vertical installation is the same, the crest value is constant, and only the time width is changed. The case of moving to L1) may be larger than the case of moving vertically.

As a result, the same effect can be obtained by controlling the deceleration pulse in the same manner.
That is, the product of the peak value of the deceleration pulse A0H and the time width in the case of movement from below to above (from L0 to L1) in the horizontal installation is determined by the product of the vertical installation (the movement from L0 to L1 is also L1). (The same applies to the movement from L0 to L0)).

  Alternatively, when deceleration pulses in horizontal installation and vertical installation are used, the time width is constant, and only the peak value is moved from lower to upper (L0 to L1) in horizontal installation, when moving in vertical installation (L0 to L1). The same applies to the movement from L1 to L0), or the acceleration pulse for horizontal installation and vertical installation, the crest value is constant, only the time width, and the horizontal installation from above to below (from L0) The case of moving to L1) may be smaller than the case of moving vertically.

Embodiment 7 FIG .
Conversely, in the case of movement from above to below (from L1 to L0) in horizontal installation, the movement from L1 to L0 in vertical installation is affected by the gravitational acceleration of -1G. The moving speed in the case of moving from above to below is higher than the moving speed from L1 to L0 in the vertical installation.

  Therefore, in order to cancel this difference and realize a stable jumping operation, in the seventh embodiment, the acceleration pulses A0V and A0H in the case of the vertical installation and the horizontal installation are moved downward from above (from L0 to L1). Also in the case of (1), the peak value or the time width is changed.

  That is, the product of the peak value of the acceleration pulse A0H and the time width when moving from the upper side to the lower side (from L0 to L1) in the horizontal installation is calculated by the following equation. The same applies to the movement of the acceleration pulse A0V).

  In addition, when the acceleration pulse of the horizontal installation and the vertical installation, the time width is constant, and only the peak value moves from the upper side to the lower side (from L1 to L0) in the horizontal installation, the movement in the vertical installation (from L0 to L1) When moving from L1 to L0), the acceleration pulse for horizontal installation and vertical installation, the peak value is constant, only the time width, and the horizontal installation, from top to bottom (from L1) The movement to L0) may be larger than the movement in the vertical installation.

As a result, the same effect can be obtained by controlling the deceleration pulse in the same manner.
That is, the product of the peak value of the deceleration pulse A0H and the time width in the case of movement from the top to the bottom (from L1 to L0) in the horizontal installation is the same as that of the movement in the vertical installation (the movement from L0 to L1 is also L1). (The same applies to the movement from L0 to L0)).

  Alternatively, when deceleration pulses in horizontal installation and vertical installation are used, the time width is constant, and only the peak value moves from top to bottom (L1 to L0) in horizontal installation, when moving in vertical installation (L0 to L1). When moving from L1 to L0, the acceleration pulse for horizontal installation and vertical installation, the peak value is constant, only the time width, and the horizontal installation, from the top to the bottom (from L1) The case of moving to L0) may be smaller than the case of moving in the vertical installation.

  In the focus pull-in method described above, when the apparatus is started or restarted, the light is always drawn first on the L1 layer of the two-layer disc, that is, on the information surface furthest to the light beam emission side. Accordingly, similarly, when the drawn layer is used as the first reference, the direction of the first focus jumping when the apparatus is started is determined.

  In other words, the direction in which the focus control is first performed and the first focus jumping moves is the L0 layer of the two-layer disc, that is, the adjacent information surface in the direction approaching the light emission side of the light beam. Here, if the information surface where the focus control was initially pulled by accident was not a normal detection surface due to an external impact, etc., or it once jumped to another information surface after pulling in the focus control. In such a case, in the case of a two-layer disc, since there is no information surface in the predetermined focus jumping direction as described above, the focus control is lost, and it is possible to return by restarting. In the case of a multi-layer disc, it is possible to move by focus jumping in any direction depending on the position of the pulled-in information surface. However, after jumping, tracking is pulled in and the address information there or predetermined information can be obtained. By moving to the track and reading the layer information written there, it can be recognized that the current position is incorrect. Therefore, it is possible to return to a predetermined information surface by restarting or performing correction jumping based on the address information.

  Further, if the number of the information surface on which the focus control is currently performed is stored in a state where the address can be read, if the focus control is lost due to vibration or shock or the information surface is pulled into another information surface. In addition, based on the stored address, it is possible to accurately return to the information surface being reproduced or recorded.

Embodiment 8 FIG .
Next, an optical disc device according to Embodiment 8 of the present invention will be described.
In the eighth embodiment, a defocus is canceled at the time of a search to realize a stable search, and will be described with reference to FIGS. 1, 13, 14, 15, and 16. FIG. 13 is a block diagram showing in detail a part that performs peak hold processing on the FE and realizes focus control in the DSP 122. FIG. 14 shows a convergent lens 105, a light beam 107a, and a light beam 107a for explaining search processing. FIG. 15 is a cross-sectional view showing the positional relationship of the disk 101. FIG. 15 shows the waveforms of F +, F- before and after the peak hold, and the difference signals FEENV and FE when a search is performed in the arrow direction A of FIG. FIG. 16 and FIG. 16 are block diagrams in which the FE detection portion by the astigmatism method of FIG. 1 is enlarged for explaining the eighth embodiment.

  Due to an adjustment error of the optical element including the photodetector 113, the level of the modulation signal of the track cross of F + and F− varies. Therefore, as shown in FIG. 15, FE, which is the difference signal between F + and F−, is affected by the track cross by the variation, and a focus shift (defocus) occurs. Therefore, during the search, disturbance due to the track cross is mixed, so that the focus shift occurs, the amplitude of the TE signal decreases, or the S / N ratio deteriorates, and the position of the light beam in the track direction is detected. Counting of the TE signal is impossible. Further, when the amount of the focus shift, that is, the amount of defocus increases, a focus jump occurs, and it is difficult to move to a target track.

  As shown in FIG. 1, the F + and F- signals obtained from the photodetector 113 via the preamplifiers 114 and 115 are above the F + and F- signals by the peak hold circuits 125a and 125b (on the mirror side of the disk 101). ) Is held, and a signal such as F + PH and F-PH in FIG. 15 which is not affected by a track cross at the time of search is generated. By taking the difference between these two signals by the differential amplifier 126, the FEENV signal shown in FIG. 15 is obtained.

  The FEENV signal is set to a predetermined amplitude by setting an optimum gain to the FEENV signal via the gain switching unit 127 and is input to the DSC 129 via the AD converter 128. Since the normal focus control, focus pull-in, and focus jumping require sufficient responsiveness, the same process as that of the related art is performed by turning on the switches B and C of the switch 401 in the DSC 129. Since it is necessary to remove the influence of the track cross appearing on the FE only during this search, the switch 401 is turned ON between A and C. As described above, by switching between the FE signal by the focus control when the normal tracking control is ON and the FE signal input under the focus control during the search, the defocus due to the influence of the track cross is suppressed. In addition, it is possible to prevent a count error and a focus jump during a search, and secure a stable search performance.

  In the eighth embodiment, the case where the astigmatism method is used as the FE detection method has been described as an example. However, the present embodiment is similarly applied to the case where another detection method is used. Can be. However, in particular, in the case of FE detection by the astigmatism method as shown in FIG. 15 described in the eighth embodiment, the effect of the track cross tends to increase, and the effect is very large.

  As described above, according to the eighth embodiment, when searching for a desired track by the search means, the peak levels of the output signals from the two light receiving areas of the light detection means are detected, and both peak level detection signals are detected. The convergence state detecting means is configured to detect the convergence state of the light beam irradiated on the information surface from the difference between the two. By switching between the FE signal when the signal is turned on and the FE signal input under the focus control during the search, the defocus due to the influence of the track cross is suppressed, and the counting error and the focus jump during the search are suppressed. Can be prevented, and an effect that stable search performance can be secured can be obtained.

Embodiment 9 FIG .
The eccentricity learning of a disk having two or more layers in the optical disk device according to the ninth embodiment of the present invention will be described with reference to FIGS.

  FIGS. 25 (a) and 25 (b) show the TE during disk eccentricity learning and the FG signal of the disk motor.

  When the power of the apparatus is turned on and a two-layer disc is mounted on the apparatus, the disc motor 102 is rotated at a predetermined number of revolutions (DMON). Next, the semiconductor laser 108 is caused to emit light (LDON), and the focus is first drawn into the second layer L1 of the two-layer disc which can be detected first by the lower light beam 107a by the above-described operation. In a state where the focus is pulled into L1, a sine-wave-like track cross signal as shown in FIG.

  The FG of the disk motor is a pulse signal of a predetermined pulse per rotation, 10 pulses in the figure according to the rotation of the motor. Therefore, in order to measure the number of TEs during one rotation of the motor (FG10 pulse), the DSP 129 converts the FG10 pulse into one rotation and one pulse, and performs zero crossing of the TE signal during the one pulse period. The operation of measuring and measuring the amount of eccentricity of the disk is performed by detecting and counting the number of times.

  After the FG of the disk motor completes the measurement of the eccentricity Df1 on the information surface L1 by the above-described method, the DSP 129 stores the information on the eccentricity Df1 at L1 in the internal eccentricity memory 306, as described above. The focus point of the light beam is moved to L0 by the focus jumping.

  Similarly to the above, the tracking control is disabled on the information surface L0, the focus control is set to the operating state, and the DSP 129 performs one rotation of the motor (FG10 pulse) from the sine-wave-like track cross signal as shown in FIG. The number of TEs during the period is counted, for example, by counting the number of zero crossings, and the eccentricity of the disk is measured. After the measurement of the amount of eccentricity on the information surface L0 is completed, the DSP 129 stores information on the amount of eccentricity at L0 in the eccentricity memory 309 inside.

  When the eccentricity information of each of the information planes L1 and L0 is stored in the internal eccentricity memory 309, the DSP 129 refers to the eccentricity amount corresponding to the information plane on which the light beam is currently controlled, and uses the amount to determine An FG signal and a sinusoidal correction signal (see FIG. 25 (b)) synchronized with the one-rotation signal obtained by dividing the FG are generated, and added to the tracking control system via the synthesizing circuit 304. To improve the following. Therefore, even when moving from L0 to L1 or from L1 to L0 in a two-layer disc, the stored eccentricity information used to generate the correction signal when performing a focus jump according to the target information surface. By switching, it is possible to construct a tracking control system that is always responsive to eccentricity.

  By the way, various other methods have been proposed for measuring and correcting eccentricity, but the present embodiment is not limited to the above-described method for measuring and correcting eccentricity. .

  As described above, according to the ninth embodiment, the information surface is skipped and scanned by the focus jumping means, and the eccentricity signal corresponding to the eccentricity of the track on the first information surface and the second information surface of the record carrier is obtained. When the interlaced scanning is performed by the focus jumping unit, the eccentricity storage signal corresponding to the jumped information surface is controlled to be added to the output of the tracking control unit. When moving between, according to the target information surface, by switching the stored eccentricity information used to generate a correction signal at the time of focus jump, it is possible to improve the followability to the eccentricity of each information surface, A tracking control system that is always responsive to eccentricity can be constructed.

Embodiment 10 FIG .
The gain learning of tracking control of a disk having two or more layers in the optical disk device according to the tenth embodiment of the present invention will be described with reference to FIG.

  FIG. 26 is a block diagram showing an internal configuration of the DSP 129 with respect to a tracking control system related to the tenth embodiment and a gain learning portion thereof in the entire block diagram of FIG.

  When the power of the apparatus is turned on and the two-layer disc is mounted, the disc motor 102 is rotated at a predetermined rotation speed (DMON). Next, the semiconductor laser 108 is caused to emit light (LDON), and the focus is first drawn into the second layer L1 of the two-layer disc which can be detected first by the lower light beam 107a by the above-described operation. Thereafter, the tracking control is turned on, and the gain learning of the tracking control is started.

  The gain measuring unit 311 in the DSP 129 applies a disturbance A having a frequency near the gain intersection to the tracking control system, and applies the tracking error signal TE (the signal at the input point of the phase compensator 302) and the tracking. A signal (a signal of the output of the switch 301) which has gone through a control loop is taken in, an open loop gain G is calculated from the two signals, and a correction amount for a desired tracking gain is calculated from the calculated current gain. Then, a signal corresponding to the signal is applied to the gain switching unit 303 via the switch 312a, and an operation of switching to a predetermined gain is performed.

  In the case of a two-layer disc, a correction amount for a desired tracking gain is calculated from the current gain measured on the information surface L1, and a corresponding switching value is added to the gain switching unit 303 via the switch 312a. At the same time as switching to the predetermined gain, the switching value is stored in the gain storage unit 312.

  After the measurement of the gain on the information surface L1 and the storage of the switching value are completed by the above method, the focal point of the light beam is moved to L0 by the above-described focus jumping.

  In the same manner as described above, a correction amount for a desired tracking gain is calculated from the current gain measured on the information surface L0, and a corresponding switching value is added to the gain switching unit 303 to switch to a predetermined gain. , The switching value is stored in the gain storage unit 312.

  After the correction amount of the tracking control gain is once calculated on each of the information surfaces L0 and L1, the gain storage unit 312 stores the correction amount of the tracking control gain on each of the information surfaces L0 and L1. The DSP 129 stores the switching value of the gain switching unit 303 corresponding to the information surface on which the light beam control is currently performed in the gain storage unit 312. Then, the information is output to the gain switching unit 312 so that the tracking gain becomes optimum in the information aspect. Therefore, even when moving from L0 to L1 or from L1 to L0 on a two-layer disc, the tracking gain is learned and the stored information surface of each stored information surface is learned when performing a focus jump according to the target information surface. By switching to the optimum value, a stable tracking control system can be constructed on any information surface.

  In the tenth embodiment, a case has been described in which a method is used in which disturbance is applied and the loop gain is directly obtained from the loop transmission signal. However, the present embodiment is directed to a case where another gain measurement method is used. Can be similarly applied.

  As described above, according to the tenth embodiment, when moving from one information surface to the other information surface in a two-layer disc, the tracking gain is learned by the previous focus jumping, and the tracking of the current focus jumping is performed. By switching the gain to the optimum value of each information surface according to the target information surface, a stable tracking control system can be constructed on any information surface.

Embodiment 11 FIG .
The gain learning of the focus control of the disk of the two or more layers in the optical disk device according to the eleventh embodiment of the present invention will be described with reference to FIG.

  FIG. 27 is a block diagram showing an internal configuration of the DSP 129 with respect to a focus control system related to the eleventh embodiment and a gain learning portion thereof in the entire block diagram of FIG.

  When the power of the apparatus is turned on and the two-layer disc is mounted, the disc motor 102 is rotated at a predetermined rotation speed (DMON). Next, the semiconductor laser 108 is caused to emit light (LDON), and the focus is first drawn into the second layer L1 of the two-layer disc which can be detected first by the lower light beam 107a by the above-described operation. Thereafter, the tracking control is turned on, and the gain learning of the focus control is started.

  The gain measurement unit 211 in the DSP 129 applies a disturbance B having a frequency near the gain intersection to the focus control system, and applies a focus error signal FE (input signal of the phase compensator 202) after the disturbance B and a focus control signal. A signal (a signal output from the switch 201) that has passed through the loop is taken in, and the gain of the open loop is calculated from the two signals. A correction amount for a desired focus gain is calculated from the calculated current gain, and a signal corresponding to the correction amount is applied to the gain switching unit 203 via the switch 212a to switch to a predetermined gain.

  In the case of a two-layer disc, a correction amount for a desired focus gain is calculated from the current gain measured on the information surface L1, and a corresponding switching value is added to the gain switching unit 203 via the switch 212a. At the same time as switching to a predetermined gain, the switching value is stored in the gain storage unit 212.

  After the measurement of the gain on the information surface L1 and the storage of the switching value are completed by the above method, the focal point of the light beam is moved to L0 by the above-described focus jumping.

  In the same manner as described above, a correction amount for a desired focus gain is calculated from the current gain measured on the information surface L0, and a corresponding switching value is added to the gain switching unit 203 via the switch 212a, and And at the same time, the switching value is stored in the gain storage unit 212.

  Once the correction amount of the focus control gain is calculated once for each of the information surfaces L0 and L1, the gain storage unit 212 stores the correction value of the focus control gain for each of the information surfaces L0 and L1. The switching value of the gain switching unit 303 is stored, and the DSP 129 outputs the gain switching value corresponding to the information surface on which the light beam is currently controlled to the gain switching unit 212 via the switch 212a, and outputs the information. Control is performed so as to obtain an optimum focus gain in terms of surface. Therefore, even when moving from L0 to L1 and from L1 to L0 on a two-layer disc, when performing a focus jump according to the target information surface, the focus is learned and the optimum value of each stored information surface is adjusted. By switching, a stable focus control system can be constructed on any information surface.

  In the above description of the eleventh embodiment, a case has been described in which a method is used in which disturbance is applied and a loop gain is directly obtained from the loop transmission signal. However, this embodiment is different from the other gain measurement methods. In the case where is used, the same can be applied.

  As described above, according to the eleventh embodiment, when moving from one information surface to the other information surface in a two-layer disc, the focus gain is learned by the previous focus jumping, and the focus gain of the current focus jumping is adjusted. By switching the gain to the optimum value of each information surface according to the target information surface, a stable focus control system can be constructed on any information surface.

Embodiment 12 FIG .
With reference to FIG. 28, description will be given of offset learning of focus control of a disk having two or more layers in the optical disk device according to the twelfth embodiment of the present invention, taking a case of a two-layer disk as an example.

  FIG. 28 is a block diagram showing the internal configuration of the DSP 129 with respect to the focus control system relating to the twelfth embodiment and the offset learning portion thereof in the overall block diagram of FIG.

  When the power of the apparatus is turned on and the two-layer disc is mounted, the disc motor 102 is rotated at a predetermined rotation speed (DMON). Next, the semiconductor laser 108 is caused to emit light (LDON), and the focus is first drawn into the second layer L1 of the two-layer disc which can be detected first by the lower light beam 107a by the above-described operation. Thereafter, the tracking control is turned ON, and offset learning of the focus control is started.

  An RFENV signal obtained by envelope detection of RF is input to the DSP 129, and the DSP 129 measures the amplitude of the RFENV signal by the focus position search unit 213, and via the switch 214a so that the amplitude becomes maximum. Then, an operation of applying a signal to the synthesizing circuit 204 to correct the focus offset is performed.

  In the case of a two-layer disc, RFENV is measured while changing the focus position by adding a signal to the synthesizing circuit 204 on the information plane L1, and the focus position search unit 213 searches for a focus position that maximizes RFENV. The offset correction value is obtained. The obtained focus offset correction value is output to the synthesizing circuit 204 via the switch 214a to correct the focus offset, and at the same time, the focus offset correction value is stored in the focus offset storage unit 214.

  After the search for the focus offset on the information plane L1 and the storage of the offset correction value are completed by the above method, the focal point of the light beam is moved to L0 by the above-described focus jumping.

  In the same manner as described above, a focus offset correction value is calculated based on the focus position searched for on the information surface L0, output to the combining circuit 204 via the switch 214a to correct the focus position, and at the same time, the focus offset correction value Cfo0 Is stored in the focus offset storage unit 214.

  After the focus offset correction values on the information surfaces L0 and L1 have been searched as described above, the focus offset value storage unit 214 stores the offset correction values for the focus control of the information surfaces L0 and L1. When performing the focus control, the DSP 129 reads the offset correction value corresponding to the information surface on which the light beam is currently controlled from the focus offset storage unit 214, and stores the offset correction value via the switch 214a. , To the synthesizing circuit 204 to perform offset correction corresponding to the information surface, and perform focus control to a correct target position.

  Therefore, even when moving from L0 to L1 and from L1 to L0 in a two-layer disc, the focus offset is learned when the focus jump is performed according to the target information surface, and this is stored in the respective information stored. Since the value is switched to the optimal value for the surface, stable focus control performance can be ensured on any information surface, and the margin of the reproduced signal can be expanded.

  By the way, in the twelfth embodiment, the focus offset of each of L0 and L1 is corrected and learned at the position where the RFENV signal is maximized, but the amplitude of the RFENV signal becomes equal. A search may be made for a midpoint between two points (because the focus position at which the RFENV signal is maximized should be at the midpoint between the two points).

  The signal for detecting the focus offset can be detected not only by the RFENV signal but also by the TE signal, the jitter signal of the reproduction signal, the C / N of the reproduction signal, or the number of data errors, or the error rate. In the present embodiment, there is no limitation in this offset detection method.

  As described above, according to the twelfth embodiment, when the focus jumping is performed on the dual-layer disc, the focus jumping corresponds to the desired target position of the focus control means on the first information surface and the second information surface of the record carrier. The offset correction values of the focus control to be performed are respectively stored in the focus position storage means, and when the focus jumping is performed this time, the target position of the focus control means is set in each information plane according to the target information plane. By switching to the optimum value, a stable focus control system can be constructed on any information surface.

Embodiment 13 FIG .
The offset learning of the tracking control of the disk having two or more layers in the optical disk device according to the thirteenth embodiment of the present invention will be described with reference to FIG. 29 taking the case of a two-layer disk as an example.

  FIG. 29 is a block diagram showing an internal configuration of the DSP 129 with respect to a tracking control system related to the thirteenth embodiment and an offset learning part thereof in the entire block diagram of FIG.

  When the power of the apparatus is turned on and the two-layer disc is mounted, the disc motor 102 is rotated at a predetermined rotation speed (DMON). Next, the semiconductor laser 108 is caused to emit light (LDON), and in the above-described operation, the focus is first drawn into the second layer L1 of the two-layer disc that can be detected first by the lower light beam 107a, and the offset learning of the tracking control is performed. To start.

  When the apparatus is turned on and a two-layer disc is mounted, the disc motor 102 is rotated at a predetermined number of revolutions (DMON). Next, in step S2, the semiconductor laser 108 is caused to emit light (LDON), and by the above-described operation, focus is first focused on the second layer L1 of the two-layer disc which can be detected first by the lower light beam 107a. .

  In the state where the focus is pulled, a sine-wave-like track cross signal as shown in FIG. 25A appears on the TE due to the influence of the eccentricity.

  The tracking offset correction unit 313 samples the sine wave TE, obtains a maximum value and a minimum value, and obtains a tracking offset from the difference between the maximum value and the minimum value. Alternatively, the TE may be sampled, its value may be integrated, and the offset may be obtained from the integrated value. The tracking offset correction unit 313 obtains a correction value to be applied to the synthesis circuit 304 based on the calculated offset, and stores the correction value in the RAM in the tracking offset correction unit 313 and outputs the correction value to the synthesis circuit 304. The operation of correcting the tracking offset is performed.

  After the measurement of the tracking offset on the information surface L1 and the storage of the correction value are completed by the above method, the focal point of the light beam is moved to L0 by the above-described focus jumping.

  Similarly to the above, the tracking control is deactivated on the information surface L0, the focus control is activated, and the sinusoidal track cross signal as shown in FIG. 25 is offset by detecting the maximum value, the minimum value, or integrating. Is measured. After the measurement of the offset of the information surface L0 is completed, the offset correction value at L0 is stored in another RAM in the tracking offset correction unit 313.

  When the tracking offset correction values of the information planes L1 and L0 are stored in the RAM, the tracking offset correction unit 313 of the DSP 129 selects an offset correction value corresponding to the information plane on which the light beam control is currently performed, That is, when the information surface on which the light beam control is currently performed is L0, the tracking offset correction value is selected, and when L1, the tracking offset correction value is selected and output to the synthesizing circuit 304 to correct the tracking offset.

  Therefore, even if the double-layer disc moves from L0 to L1 or from L1 to L0, the focus offset correction value corresponding to the information surface of the target layer is determined when performing a focus jump according to the target information surface. By setting to, the offset of the tracking control system can always be removed, and stable tracking control can be constructed.

  By the way, various other methods have been proposed for offset measurement and correction. However, the present embodiment is not limited at all by the offset measurement and correction method.

  As described above, according to the thirteenth embodiment, when the focus jumping is performed on the two-layer disc, the focus jumping corresponds to the desired target position of the tracking control means on the first information surface and the second information surface of the record carrier. The tracking offset correction values to be performed are respectively stored in the tracking position storage means, and at the time of focus jumping, the target position of the tracking control means is set to the optimum value for each information surface in accordance with the target information surface. By switching to a value, a stable tracking control system can be constructed on any information surface.

Embodiment 14 FIG .
In the optical disc device according to the fourteenth embodiment of the present invention, offset learning of tracking control of a disc having two or more layers will be described with reference to FIG. 30, taking a case of a two-layer disc as an example.

  FIG. 30 shows a phase difference tracking control system related to the fourteenth embodiment of the entire block diagram of FIG. 1 and a portion for correcting an offset (hereinafter, referred to as a phase difference offset) associated with the phase difference. , A DSP 129 and a peripheral configuration thereof.

  When the power of the apparatus is turned on and the two-layer disc is mounted, the disc motor 102 is rotated at a predetermined rotation speed (DMON). Next, in step S2, the semiconductor laser 108 is caused to emit light (LDON), and the above-described operation first focuses on the second layer L1 of the two-layer disc that can be detected first by the lower light beam 107a. In the state where the focus is pulled, a sinusoidal track cross signal as shown in FIG. 25 appears on the TE due to the influence of the eccentricity.

  The DSP 129 applies a signal to the synthesizing circuit 304 by the lens shift unit 317, forcibly supplies a current to the tracking actuator 103 to give an offset, and shifts the converging lens 105 by about +300 μm. In the state where the lens is shifted, the symmetry detection unit 318 samples the sine wave TE, obtains the maximum value and the minimum value, and obtains the tracking symmetry Voff + on the lens shift + side from the difference. Alternatively, TE may be sampled, its value integrated, and the symmetry determined by the integrated value.

  Next, the polarity of the output signal of the lens shift unit 317 is switched, and in a state where the lens is shifted by about −300 μm, the symmetry detection unit 318 samples the TE on the sine wave to obtain a maximum value and a minimum value. From the difference, a tracking symmetry Voff- on the lens shift side is obtained. Alternatively, TE may be sampled, its value integrated, and the symmetry determined by the integrated value.

  The delay amount (or advance amount) Pd1 of the variable delay devices 315 and 316 is switched so that the difference between the calculated offsets of the positive and negative lens shifts is minimized.

  When the minimum delay amount is determined, an output value for setting the delay amount is stored in the phase difference correction amount storage unit 319.

  By the above method, the delay amounts of the variable delay units 315 and 316, which are the correction values of the phase difference offset of the phase difference tracking on the information surface L1, are set, and the set values are stored in the phase difference correction amount storage unit 319. After completion, the focal point of the light beam is moved to L0 by the above-described focus jumping.

  In the same manner as described above, the tracking control is deactivated on the information surface L0, the focus control is activated, and the optimum delay amount Pd0 for correcting the phase difference offset is determined.

  When the delay amounts (or advance amounts) Pd1 and Pd0 of the variable delay units 315 and 316 on the information plane L0 are determined, the output values for setting the delay amounts are stored in the phase difference correction amount storage unit 319.

  Once the set values Pd1 and Pd0 of the variable delay devices 315 and 316 for correcting the phase difference offset of the phase difference tracking on the information surfaces of L1 and L0 are stored in the phase difference correction amount storage unit 319, After that, the DSP 129 selects a delay amount corresponding to the information plane on which the light beam is currently controlled, and sets the selected delay amount in the variable delay devices 315 and 316 via the switch 319a.

  Therefore, even when moving from L0 to L1 or from L1 to L0 on a two-layer disc, when performing a focus jump according to the target information surface, the variable delay device 315 corresponding to the target layer information surface is used. Since the delay amounts Pd1 and Pd0 of 316 can be set, the offset of the tracking control system when the lens shifts can be always removed, and stable tracking control can be constructed.

  By the way, various other methods have been proposed for measuring and correcting the phase difference offset, but the present invention is not limited at all by the offset measuring and correcting method.

  As described above, according to the fourteenth embodiment, when the reflected light from the record carrier is received by a plurality of divided regions, the reflected light is output based on the phase relationship between the output signals of the respective light receiving regions of the light detecting means. Generating a phase difference track shift signal corresponding to the positional relationship between the convergence point of the light beam on the information surface and the track, and the tracking control means controls the moving means in accordance with the output signal of the phase difference track shift detection means. The tracking control is performed by driving, and the information surface is skipped and scanned by the focus jumping means, and the output signal of the phase difference track deviation detecting means on the first information surface and the second information surface of the record carrier is desired. The amount of advance or lag of the signal in each light receiving area of the light detecting means, which is the output of the light detecting means, is stored as the amount of phase cancellation, and is stored in the focus jumping means. At the time of interlaced scanning, a phase cancellation amount storage signal corresponding to the information plane to be skipped is read out from the phase cancellation amount storage means, and the delay amount or advance amount of the signal of each light receiving area of the light detection means is switched. Therefore, even if a two-layer disc moves between two information planes, a focus offset corresponding to the information plane of the target layer is performed when performing a focus jump according to the target information plane. By setting the correction value, the offset of the tracking control system can always be removed, and stable tracking control can be constructed.

  INDUSTRIAL APPLICABILITY The optical disk device of the present invention can be used as an optical disk device capable of performing high-speed and safe focus control on a large-capacity multilayer disk.

FIG. 1 is a block diagram of an optical recording / reproducing apparatus according to Embodiment 1 of the present invention. FIG. 2 is a block diagram showing details of a portion relating to focus control and focus pull-in of FIG. 1 according to the first embodiment. FIG. 3 is a waveform chart showing a relationship between a disc, an UP / DOWN signal, and an FE signal in CDs and DVDs (FIGS. 1A and 1B) having different substrate thicknesses according to the first embodiment. FIG. 4 is a waveform chart showing FE, UP / DOWN signals, and AS signals in CDs and DVDs having different substrate thicknesses at the time of focus pull-in according to the first embodiment. 5 is a flowchart of focus pull-in processing for explaining the operation of the first embodiment. FIG. 2 is a diagram showing a cross section of a two-layer and multilayer disc used in the present invention. FIG. 9 is a diagram illustrating waveforms of a lens drive signal and an FE signal for explaining a pull-in operation of focus control and a converging lens position at each stage according to the second embodiment of the present invention. FIG. 13 is a waveform chart of an FE signal, a lens drive signal, and an RF signal for describing a pull-in operation of focus control according to the second embodiment. 9 is a flowchart illustrating a flow of a pull-in operation according to the second embodiment. FIG. 9 is a block diagram showing a tracking control and particularly an eccentricity correction part in detail for explaining a third embodiment of the present invention; FIG. 13 is a waveform diagram of an FE signal, a lens drive signal, and a TE signal during focus jumping, which is a jump operation of focus control, according to the third embodiment. 13 is a flowchart illustrating a jump operation of focus control according to the third embodiment. FIG. 10 is a block diagram showing a peak hold of focus control and a part of the control in detail for describing Embodiment 3; FIG. 14 is a diagram for explaining a search for a dual-layer disc according to the fourth embodiment of the present invention. FIG. 17 is a waveform chart of F +, F− during search, F + PH, F−PH obtained by peak-holding this signal, and FE and FEENV, which are difference signals, according to the fourth embodiment. FIG. 14 is a block diagram showing a circuit block in the case where FE is detected by the astigmatism method in the fourth embodiment. 15 is a flowchart showing a processing flow when a two-layer disc is mounted and activated according to the fifth embodiment of the present invention. FIG. 4 is a diagram for explaining a focus jumping operation for moving from one information surface to another information surface according to the first embodiment of the present invention. FIG. 2 is a block diagram showing a configuration of a conventional focus control device. FIG. 9 is a waveform diagram for explaining a pull-in operation of a conventional focus control. FIG. 9 is a waveform diagram for explaining a pull-in operation of a conventional focus control. 9 is a flowchart showing the flow of a conventional focus control pull-in operation. FIGS. 19A to 19I show light detection spots when the FE signal is at points A to I in FIG. 18, respectively, in the first embodiment of the present invention. FIG. 32 is a diagram for describing offset learning of tracking control of a disk having two or more layers according to the fourteenth embodiment of the present invention. FIG. 27 is a diagram illustrating TE, an FG signal of a disk motor, and an eccentricity correction signal generated by a DSP at the time of disk eccentricity learning in Embodiment 9 of the present invention. FIG. 21 is a diagram for describing gain learning for tracking control of a disk having two or more layers according to the tenth embodiment of the present invention. FIG. 33 is a diagram for explaining gain learning of focus control for a disc having two or more layers according to the eleventh embodiment of the present invention. FIG. 33 is a diagram for describing offset learning of focus control of a disc having two or more layers according to the twelfth embodiment of the present invention. FIG. 33 is a diagram for describing offset learning of tracking control of a disk having two or more layers according to Embodiment 13 of the present invention.

Explanation of reference numerals

Reference Signs List 6 disc motor 7 disc 8 light beam 12 photodetector 14 differential amplifier 17 gain switching circuit 19 linear motor 20 microprocessor 21 core 22 port 23 phase compensation circuit 24 S-shaped detection section 25 UP / DOWN section 26 motor control 27 laser control Unit 33 switch 34 linear motor control circuit 35 drive circuit 36 focus actuator 37 motor control circuit 38 laser drive circuit 101 disk 102 disk motor 103 tracking actuator 104 focus actuator 105 convergent lens 106 hologram lens 107 convergent point 108 semiconductor laser 109 coupling lens 110 Deflection beam splitter 111 Condensing lens 112 Split mirror 113 Photodetector 114 Preamplifier 115 Amplifier 116 Adder 117 adds 118 the comparator 119 comparator 120 differential amplifier 121 gain switching unit 122 the gain switching unit 123 AD converter 124 AD converter 125 peak hold circuit 126 differential amplifier 127 gain switching unit 128 AD converter 129 DSP
130 drive circuit 131 drive circuit 132 FG generator 133 differential amplifier 134 phase comparator 201 switch 202 phase compensation filter 203 gain switching section 204 switch 205 S-shaped detection section 206 level determination section 207 waveform generation section 208 HOLD section 209 DA converter 301 switch 302 phase compensation filter 303 gain switching unit 304 synthesis circuit 305 switch 306 eccentric memory 307 JMP pulse generation unit 308 HOLD unit 401 switch

Claims (14)

Converging means for converging and irradiating a light beam on a record carrier having two information surfaces;
Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier;
Light detection means for receiving reflected light from the record carrier of the converged light beam,
The convergence state of the light beam irradiated on the information surface is detected based on the output signal of the light detection means, and the moving means is driven based on the detection signal, and the convergence state of the light beam is determined. Focus control means for controlling to be in a state of
Focus jumping means for driving the moving means to move the convergence point of the light beam from the first information surface to the second information surface of the record carrier;
A signal corresponding to the amount of reflected light obtained from the light detecting means when the moving means is driven so as to move the light beam away from or near the record carrier to pass through the first and second information surfaces. Reflected light amount storage means for storing
When the focus jumping by the focus jumping means, according to the value stored in the reflected light amount storage means, the gain of the focus control means was switched,
An optical disc device characterized by the above-mentioned. The optical disc device according to claim 1,
When the focus jumping is performed by the focus jumping unit, the pull-in level of the focus control is set according to the value stored in the reflected light amount storage unit,
An optical disc device characterized by the above-mentioned. The optical disc device according to claim 1,
According to the output signal of the focus control unit that has switched the gain according to the value stored in the reflected light amount storage unit, the pull-in level of the focus control at the time of focus jumping is set.
An optical disc device characterized by the above-mentioned. Converging means for converging and irradiating a light beam on a record carrier having two information surfaces;
Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier;
Light detection means for receiving reflected light from the record carrier of the converged light beam,
The convergence state of the light beam irradiated on the information surface is detected based on the output signal of the light detection means, and the moving means is driven based on the detection signal, and the convergence state of the light beam is determined. Focus control means for controlling to be in a state of
Focus jumping means for driving the moving means to move the convergence point of the light beam from the first information surface to the second information surface of the record carrier;
Convergence state detection for storing the convergence state detection signal obtained when the moving means is driven so as to move the light beam away from or near the record carrier to pass through the first and second information surfaces. Signal storage means,
When the focus jumping by the focus jumping means, according to the value stored in the convergence state detection signal storage means, the gain of the focus control means was switched,
An optical disc device characterized by the above-mentioned. The optical disc device according to claim 2,
When the focus jumping is performed by the focus jumping means, the pull-in level of the focus control is set according to the value stored in the convergence state detection signal storage means.
An optical disc device characterized by the above-mentioned. The optical disc device according to claim 2,
According to the value stored in the convergence state detection signal storage means, according to the signal of the focus control means that has switched the gain, to set the pull-in level of the focus control at the time of focus jumping,
An optical disc device characterized by the above-mentioned. Converging means for converging and irradiating a light beam on a record carrier having two information surfaces;
Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier;
Light detection means for receiving reflected light from the record carrier,
Reflected light amount detecting means for detecting a signal corresponding to the reflected light amount obtained from the light detecting means,
A convergence state detection means for detecting a convergence state of a light beam irradiated on the information surface based on an output signal of the light detection means,
Division means for dividing the signal of the convergence state detection means by the signal of the reflected light amount detection means,
Focusing jumping means for driving the moving means based on the signal of the dividing means to move the convergence point of the light beam from the first information surface to the second information surface of the record carrier;
An optical disc device characterized by the above-mentioned. Converging means for converging and irradiating a light beam on the record carrier;
Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier;
Light detection means having at least two light receiving areas for receiving the reflected light from the record carrier;
Convergence state detection means for detecting a convergence state of a light beam irradiated on the information surface based on a difference between output signals from two light receiving regions of the light detection means;
A focus control unit that drives the moving unit based on an output signal of the convergence state detection unit and controls the convergence state of the light beam to be a predetermined state;
The light beam is driven in a direction perpendicular to the track on the record carrier, having a search means to search for a desired track,
The convergence state detecting means detects a peak level of an output signal from two light receiving regions of the light detecting means when searching for a desired track by the searching means, and obtains the information based on a difference between the two peak level detection signals. It is configured to detect the convergence state of the light beam irradiated on the surface,
An optical disc device characterized by the above-mentioned. An optical disc device for converging and irradiating a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier,
Moving means for moving the light beam on the record carrier across the track;
Tracking control means for detecting a displacement between the light beam on the record carrier and the track, driving the moving means in accordance with the track displacement signal, and controlling the light beam on the record carrier to be located on the track; When,
Focus jumping means for causing the light beam to jump scan between a position on the first information surface and a position on the second information surface of the record carrier;
Eccentric signal storage means for storing eccentric signals corresponding to the eccentricity of the tracks on the first information surface and the second information surface of the record carrier when the information jump is performed by the focus jumping means. ,
Adding means for adding the eccentricity storage signal stored in the eccentricity signal storage means to the output signal of the tracking control means,
System control means for controlling so as to add the eccentricity storage signal read from the eccentricity signal storage means corresponding to the information surface to be interlaced when the interlaced scanning is performed by the focus jumping means to the tracking control means. ,
An optical disc device characterized by the above-mentioned. An optical disc device for converging and irradiating a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier,
Moving means for moving the light beam on the record carrier across the track;
Tracking control means for detecting a displacement between the light beam on the record carrier and the track, driving the moving means in accordance with the track displacement signal, and controlling the light beam on the record carrier to be located on the track; When,
Focus jumping means for causing the light beam to jump scan between a position on the first information surface and a position on the second information surface of the record carrier;
Tracking gain storage means for storing desired loop gains of the tracking control means on the first information surface and the second information surface of the record carrier when the information surface is skipped and scanned by the focus jumping means, respectively; When,
Multiplying means for multiplying a tracking gain storage signal stored in the tracking gain storage means by an output signal of the tracking control means;
A system control means for controlling so as to multiply a signal of the tracking control means by a tracking gain storage signal read from the tracking gain storage means, which corresponds to the information plane to be skipped, when performing interlaced scanning by the focus jumping means; With,
An optical disc device characterized by the above-mentioned. An optical disc device for converging and irradiating a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier,
Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier;
Light detection means for receiving reflected light from the record carrier,
The convergence state of the light beam irradiated on the information surface is detected based on the output signal of the light detection means, and the moving means is driven based on the detection signal, and the convergence state of the light beam is in a predetermined state. Focus control means for controlling so that
Focus jumping means for causing the light beam to jump scan between a position on the first information surface and a position on the second information surface of the record carrier;
Focus gain storage means for storing desired loop gains of the focus control means on the first information surface and the second information surface of the record carrier when the information surface is skipped and scanned by the focus jumping means, respectively; ,
Multiplying means for multiplying an output signal of the focus control means by a focus gain storage signal stored in the focus gain storage means,
When the interlaced scanning is performed by the focus jumping unit, an output for controlling the focus control unit to multiply a signal of the focus control unit by a focus gain storage signal read from the focus gain storage unit corresponding to the information plane to be skipped. Equipped,
An optical disc device characterized by the above-mentioned. An optical disc device for converging and irradiating a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier,
Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the information surface of the record carrier;
Light detection means for receiving reflected light from the record carrier,
The convergence state of the light beam irradiated on the information surface is detected based on the output signal of the light detection means, and the moving means is driven based on the detection signal, and the convergence state of the light beam is in a predetermined state. Focus control means for controlling so that
Focus jumping means for causing the light beam to jump scan between a position on the first information surface and a position on the second information surface of the record carrier;
Focus position storage means for storing desired target positions of the focus control means on the first information surface and the second information surface of the record carrier when the information surface is skipped and scanned by the focus jumping means, respectively; ,
A system control means for controlling a focus position storage signal read from the focus position storage means, corresponding to an information plane to be skipped, to switch a target position of the focus control means when performing interlaced scanning by the focus jumping means. With,
An optical disc device characterized by the above-mentioned. An optical disc device for converging and irradiating a light beam onto a record carrier having two information surfaces to reproduce information recorded on the record carrier,
Moving means for moving the light beam on the record carrier across the track;
Tracking control means for detecting a displacement between the light beam on the record carrier and the track, driving the moving means in accordance with the track displacement signal, and controlling the light beam on the record carrier to be located on the track; When,
Focus jumping means for causing the light beam to jump scan between a position on the first information surface and a position on the second information surface of the record carrier;
Tracking position storage means for storing desired target positions of the tracking control means on the first information surface and the second information surface of the record carrier when the information surface is skipped and scanned by the focus jumping means, respectively; ,
System control means for controlling the switching of the target position of the tracking control means to a tracking position storage signal read from the tracking position storage means corresponding to the information plane to be jumped when performing interlaced scanning by the focus jumping means. With,
An optical disc device characterized by the above-mentioned. Converging means for converging and irradiating a light beam on a record carrier having two information surfaces;
Moving means for moving the convergence point of the light beam converged by the converging means in a direction substantially perpendicular to the direction of the record carrier surface and the track;
Light detection means for receiving the reflected light from the record carrier in a plurality of divided regions,
Phase difference track shift detection for generating a phase difference track shift signal corresponding to the positional relationship between the convergence point of the light beam on the information surface and the track based on the phase relationship between the output signals of the respective light receiving regions of the light detecting means. Means,
Driving the moving means in response to the output signal of the phase difference track deviation detecting means, tracking control means for controlling the convergence point of the light beam on the record carrier to scan the track correctly,
Focus jumping means for causing the light beam to jump scan between a position on the first information surface and a position on the second information surface of the record carrier;
The output signal of the phase difference track deviation detecting means on the first information surface and the second information surface of the record carrier when the information surface is skipped and scanned by the focus jumping means has a desired output. Phase cancellation amount storage means for storing the amount of advance or lag of a signal in each light receiving area of the light detection means;
When the interlaced scanning is performed by the focus jumping unit, the delay amount or the advance amount of the signal of each light receiving area of the light detection unit is determined by the phase cancellation amount read from the phase cancellation amount storage unit corresponding to the information plane to be skipped. System control means for controlling to switch to the stored signal,
An optical disc device characterized by the above-mentioned.

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