JP2009037672A - Optical pickup device and optical disk device using the same - Google Patents

Abstract

An optical element driving means for holding and driving an optical element moved in the direction of an optical axis is simplified in an adjustment process and the positional accuracy of the optical element is improved.
A base member 20 provided with a light source and an optical system for guiding an emitted light beam to an optical disc, and an optical element 26 provided in the optical path so as to be movable in the optical axis direction with respect to the base member 20. Optical element driving means 30 for driving the optical element in the optical axis direction. The driving means 30 includes a holding part 31 for holding the optical element, and a main shaft 32 and a sub-axis 33 for supporting the holding part 31 movably in the optical axis direction. The base member 20 supports the main shaft 32 and supports the first positioning portion 41 for positioning the main shaft 32 so that the position of the main shaft 32 is a predetermined position. A second positioning unit 42 is provided for positioning the optical element driving means 30 positioned by the positioning unit 41 so that the attitude around the axis about the main shaft 32 is a predetermined attitude.
[Selection] Figure 6

Description

  The present invention relates to an optical pickup apparatus that records and / or reproduces information signals with respect to an optical disc, and includes an optical element driving unit that drives an optical element provided in the optical path in the optical axis direction. The present invention relates to an optical disc apparatus using the same.

  Conventionally, optical discs such as CDs (Compact Discs) and DVDs (Digital Versatile Discs) have been used as recording media for information signals. Information signals are recorded on this type of optical discs, or information signals recorded on optical discs are reproduced. There is an optical disc device for performing the above-mentioned, and this optical disc device is provided with an optical pickup device that moves in the radial direction of the optical disc and irradiates the optical disc with a light beam.

  This optical pickup device generally has an OP base, and an optical system such as a light source, an objective lens, a light receiving unit, and other optical elements is provided on the OP base. In recent years, there are optical pickup devices compatible with a plurality of types of optical discs. Such an optical pickup device is a lens driving unit for driving a lens provided in an optical path from a light source to an objective lens in an optical axis direction. Some are provided.

  When fixing the lens driving unit to the OP base, conventionally, it has been common to provide a reference surface, a boss or a hole on the unit base or the OP base of the lens driving unit, and fix them by screwing or bonding. At this time, it is usually desirable to suppress the eccentricity of the optical axis of the lens driven by the lens driving unit to less than 0.1 mm with respect to the optical axis of the reference optical system. Considering the assembly tolerance and mounting tolerance on the OP base, assembly accuracy of around 0.03mm is required for a single unit. It is necessary to manage this, and as a result, the yield is lowered, and as a result, the cost of the lens driving unit is increased.

  In addition, the lens driving unit is required to drive very accurately and smoothly with a vibration of less than 3 μm with respect to vibration when driving the lens. In a conventional lens drive unit, the main and sub shafts that serve as guide shafts for the lens drive unit are press-fitted and bonded to the unit base, so the vibration of the drive means such as a motor mounted on the unit base is subject to vibration. It was also a problem that the vibration when the lens was driven was amplified by being transmitted to the base.

  In addition, there is also a method of screwing the drive unit when mounting the drive unit on the OP base. However, this method increases both the unit and the installation space, and makes the entire device larger or screw-fastened. There are also concerns about problems such as cracking of the flange.

  In addition, as a highly accurate mounting method, there is a method of spatially adjusting and fixing the lens drive unit to the OP base, but the complexity of the adjustment process, adjustment man-hours, reliability due to space bonding, and dedicated equipment are required. There were many problems. Further, when the unit base of the lens driving unit is made of resin, the resin base is distorted due to the temperature characteristics, and the shaft press-fitted therewith is also tilted accordingly, which deteriorates the lens position accuracy.

  As described above, when a drive unit for driving an optical element such as a lens provided in the optical pickup device is provided, an individual assembly error of the unit and an error when the unit is attached to the OP base are individually generated. There is a problem that the overall error increases due to the superposition of these.

JP 2006-4578 A

  An object of the present invention is to simplify an adjustment process when attaching an optical element driving means for holding and driving an optical element moved in the optical axis direction to a base member on which another optical component is mounted. It is an object of the present invention to provide an optical pickup device that can improve the positional accuracy of an optical element held by the optical device and an optical disk device using the same.

  In order to achieve this object, an optical pickup device according to the present invention includes a base member provided with at least a light source, an optical system for guiding a light beam emitted from the light source to an optical disc, and an optical path of the optical system. Optical element driving means for driving in the optical axis direction an optical element provided to be movable in the optical axis direction with respect to the base member, and the optical element driving means holds the optical element And a main shaft and a sub shaft which are formed in the optical axis direction and support the holding portion so as to be movable in the optical axis direction. The base member supports the main shaft and the base of the main shaft. A first positioning portion that positions the member so that the position relative to the member is a predetermined position, and the optical element driving means that supports the auxiliary shaft and positions the main shaft by the first positioning portion. A second positioning portion is provided for positioning so that a posture in a direction around the axis with respect to the main shaft becomes a predetermined posture, and the first positioning portion and the second positioning portion include the main shaft and the second positioning portion, respectively. By supporting the countershaft, the position and posture of the optical element driving means with respect to the base member are restricted to a predetermined position and posture.

  In order to achieve this object, an optical disc apparatus according to the present invention includes a driving unit that holds and rotates an optical disc, and an optical signal that is radiated to the optical disc that is rotated by the driving unit. An optical pickup device having an optical pickup device for recording and / or reproduction, and the above-described optical pickup device used for the optical disc device is used.

  In the present invention, the main shaft and the sub shaft of the optical element driving means serving as a guide for moving the optical element are directly attached to the first and second positioning portions provided on the base member to which another optical component is attached. Thus, it is possible to prevent the error of each component or each assembly part from being added in a superimposed manner and to generate a large error as a whole, and the optical element provided in the optical element driving means with a simple configuration It is possible to improve the positional accuracy.

  Hereinafter, an optical disk device using an optical pickup device to which the present invention is applied will be described with reference to the drawings. As shown in FIG. 1, the optical disc apparatus 101 is a recording / reproducing apparatus that records and / or reproduces information signals with respect to the optical disc 102.

  As the optical disk 102 to be recorded and / or reproduced by the optical disk device 101, for example, a CD (Compact Disc), a DVD (Digital Versatile Disc), a CD-R (Recordable) and a DVD-R (information recordable) are available. Recordable), CD-RW (ReWritable), DVD-RW (ReWritable), DVD + RW (ReWritable), and other optical disks that can be rewritten, and semiconductor lasers with a shorter emission wavelength of about 405 nm (blue-violet) An optical disk capable of high-density recording, a magneto-optical disk, or the like is used.

  As shown in FIG. 1, an optical disk apparatus 101 includes a spindle motor 103 as a driving means for rotationally driving an optical disk 102, an optical pickup apparatus 1, and a feed motor as a driving means for moving the optical pickup apparatus 1 in the radial direction. 105. Here, the spindle motor 103 is controlled by the system controller 107 and the control circuit unit 109 so as to be driven at a predetermined rotational speed.

  The signal modulation / demodulation unit and ECC block 108 modulates and demodulates a signal output from the signal processing unit 120 and adds an ECC (error correction code). The optical pickup device 1 irradiates the signal recording surface of the optical disc 102 rotating according to instructions from the system controller 107 and the control circuit unit 109 with a light beam. Information signals are recorded on the optical disc 102 by such light beam irradiation, and the information signals recorded on the optical disc are reproduced.

  Further, the optical pickup device 1 detects various light beams as will be described later based on the reflected light beam reflected from the signal recording surface of the optical disc 102, and uses the signal processing unit 120 to detect detection signals obtained from the respective light beams. It is comprised so that it may supply.

  The signal processing unit 120 generates various servo signals based on detection signals obtained by detecting each light beam, that is, a focus error signal and a tracking error signal, and is an information signal recorded on the optical disc. An RF signal is generated. Also, predetermined processing such as demodulation and error correction processing based on these signals is performed by the control circuit unit 109, the signal modulation and ECC block 108, and the like according to the type of recording medium to be reproduced.

  Here, if the recording signal demodulated by the signal modulation and ECC block 108 is, for example, for data storage of a computer, it is sent to the external computer 130 or the like via the interface 111. Accordingly, the external computer 130 and the like are configured to receive a signal recorded on the optical disc 102 as a reproduction signal.

  Also, if the recording signal demodulated by the signal modulation and ECC block 108 is for audio / visual use, the digital / analog conversion is performed by the D / A conversion unit of the D / A and A / D converter 112 for audio / visual processing. Supplied to the unit 113. Audio / video signal processing is performed by the audio / visual processing unit 113 and transmitted to an external imaging / projection device via the audio / visual signal input / output unit 114.

  A feed motor 105 is connected to the optical pickup device 1. The optical pickup device 1 is moved in the radial direction of the optical disc 102 by the rotation of the feed motor 105 and moved to a predetermined recording track on the optical disc 102. The control of the spindle motor 103, the control of the feed motor 105, and the control of the objective lens driving mechanism that moves and displaces the objective lens of the optical pickup device 1 in the focus direction in the optical axis direction and the tracking direction orthogonal to the optical axis direction are as follows: Each is performed by the control circuit unit 109.

  That is, the control circuit unit 109 controls the spindle motor 103 and controls the objective lens driving mechanism based on the focus error signal and the tracking error signal.

  Further, the control circuit unit 109 is driven to supply a tracking coil and a focus coil provided in the optical pickup device 1 based on a focus error signal, a tracking error signal, an RF signal, and the like input from the signal processing unit 120. Each of the signals (drive currents) is generated.

  The laser control unit 121 controls the laser light source in the optical pickup device 1.

  Here, the focus direction F refers to the optical axis direction of the objective lenses 23 and 24 of the optical pickup device 1, and the tangential direction Tz is a direction orthogonal to the focus direction F and is the circumference of the optical disc device 101. The direction parallel to the tangential direction is referred to, and the tracking direction T is a direction orthogonal to the focus direction F and the tangential Tz direction.

  Next, the optical pickup device 1 to which the present invention is applied will be described in detail.

  The optical pickup device 1 records and / or reproduces an information signal on a plurality of types of optical discs 102 on which information signals are recorded or reproduced by selectively using a plurality of types of light beams having different wavelengths. The optical disk device is used in an optical disk device. Specifically, a first optical disk on which an information signal is recorded or reproduced using a light beam having a first wavelength of about 760 to 800 nm, and a wavelength of about 650 to 660 nm. The information signal is recorded or reproduced using the second optical disk on which the information signal is recorded or reproduced using the light beam having the second wavelength and the light beam having the third wavelength of about 400 to 410 nm. In the following description, it is assumed that information signals are recorded and / or reproduced with respect to the third optical disc.

  In the following description, the optical pickup device 1 is described as performing recording and / or reproduction of an information signal on three different types of optical discs. However, the present invention is not limited to this. An information signal may be recorded and / or reproduced on an optical disc.

  The optical pickup device 1 to which the present invention is applied is reflected from the first and second light sources 21 and 22 composed of semiconductor lasers or the like that emit a plurality of types of light beams having different wavelengths, and the signal recording surface of the optical disk 102. As a light detection element for detecting the reflected light beam, the light beams from the first and second light sources 21 and 22 are guided to the optical disk 102, and the light beam reflected by the optical disk 102 is used as the light detection element. And a guiding optical system.

  Here, the first light source 21 includes an emission unit that emits a light beam having a first wavelength and an emission unit that emits a light beam having a second wavelength. The second light source 22 includes: And an emission part for emitting a light beam of the third wavelength.

  As shown in FIGS. 2 and 3, the optical pickup apparatus 1 includes a pickup base (OP as an attachment base for various components provided in a casing of the optical disk apparatus 101 so as to be movable in the radial direction R of the optical disk 102. Base) 20 is provided.

  Further, as shown in FIGS. 2 to 5, the optical pickup device 1 includes a lens holder 12 that supports a plurality of objective lenses 23 and 24 that collect a light beam emitted from a light source and irradiate the optical disk, and a lens holder. 12 is arranged at a distance in the tangential direction Tz and is attached to a pickup base 20 as an attachment base, and the lens holder 12 can be moved in the focus direction F and the tracking direction T with respect to the support 13. And a plurality of support arms 14 to be supported. The lens holder 12, the support 13, and the support arm 14, together with coils 51 and 52 and a magnet 53, which will be described later, an objective lens driving mechanism that drives the objective lenses 23 and 24 in the focus direction F and the tracking direction T as described later. Function as. The first and second objective lenses 23 and 24 constitute a part of the optical system of the optical pickup device 1.

  The optical pickup device 1 is configured to include a plurality of objective lenses 23 and 24 that are arranged in the tangential direction Tz. However, the number and arrangement of the objective lenses are not limited thereto, and for example, a plurality of objective lenses may be provided. The objective lens may be arranged in the radial direction R, or may be configured to include one objective lens.

  As an optical system for guiding the light beams emitted from the first and second light sources 21 and 22 to the optical disc 102, at least a beam for combining the optical paths of the light beams emitted from the first and second light sources 21 and 22 is used. A splitter 25, a collimator lens 26 that converts the divergence angles of the light beams combined by the beam splitter 25 into substantially parallel light, and transmits the third wavelength light beam and the first and second light beams. A first rising mirror 27 that reflects a light beam having a wavelength and enters the first objective lens 23, and a second light beam that passes through the first rising mirror 27 and reflects the second light beam. The second raising mirror 28 that is incident on the objective lens 24 and the above-described first and second objective lenses 23 and 24 are provided. In FIG. 4, L1 indicates the optical path of the light beam emitted from the first light source 21, L2 indicates the optical path of the light beam emitted from the second light source 22, and L3 is obtained by the beam splitter 25. The optical paths of the light beams emitted from the first and second light sources 21 and 22 after being combined are shown.

  Further, the optical pickup device 1 is provided with an actuator 30 as an optical element driving means for moving the collimator lens 26 in the optical axis direction. The collimator lens 26 is moved in the optical axis direction by the actuator 30 so that the divergence angle of the light beam after passing through the collimator lens 26 can be changed, thereby correcting and reducing the aberration. . That is, the moving direction Y of the collimator lens 26 moved by the actuator 30 is the direction of the optical path of the light beam synthesized by the beam splitter 25 indicated by L3 in FIG.

  That is, the actuator 30 and the collimator lens 26 moved to the actuator 30 are generated by using a light beam having a plurality of types of wavelengths and using a common objective lens for a plurality of types of optical discs due to the change in the divergence angle. For example, it is possible to correct spherical aberration and the like, and it is possible to correct a focus position shift due to vibration, impact, temperature change, and the like by the defocus component accompanying the change in the divergence angle.

  As shown in FIGS. 6 and 7, the actuator 30 as the optical element driving means is movable in the optical axis direction of the collimator lens 26 as the optical element, and holds the collimator lens 26, and the collimator lens. 26 is formed in the direction of the optical axis, supports the holding unit 31 so as to be movable in the optical axis direction, and serves as a guide means when moving the holding unit 31. And a drive motor 34 for driving the held collimator lens 26. The main shaft 32 and the sub shaft 33 are provided substantially parallel to each other so that the axial direction thereof is parallel to the optical axis direction of the collimator lens 26.

  On the other hand, the pickup base 20 as a base member to which the actuator 30 is attached includes a first positioning portion 41 that supports the main shaft 32 and positions the main shaft 32, and a sub shaft 33 that supports the sub shaft 33. A second positioning portion 42 for positioning is provided. The first positioning unit 41 supports the main shaft 32 so that the position of the main shaft 32 with respect to the pickup base 20 and the optical component attached thereto is a predetermined spatial position, and the second positioning unit 41 42 supports the auxiliary shaft 33 and positions the auxiliary shaft 33 in a predetermined direction with respect to the pickup base 20 of the auxiliary shaft 33 and the optical components attached thereto, whereby the position of the main shaft 32 is determined by the first positioning portion 41. Positioning is performed so that the posture around the axis about the main shaft 32 of the positioned actuator 30 is a predetermined posture.

  As described above, the first positioning portion 41 and the second positioning portion 42 support the main shaft 32 and the sub shaft 33, respectively, thereby changing the position and posture of the actuator 30 with respect to the pickup base 20 to a predetermined spatial position and posture. Regulate to be.

  Specifically, as shown in FIGS. 6 and 8, the main shaft 32 of the actuator 30 has a substantially circular cross section orthogonal to the optical axis direction of the collimator lens 26, that is, a cross section orthogonal to the formation direction of the main shaft 32. Is formed.

  As shown in FIGS. 6 and 8, the first positioning portion 41 is formed in a concave shape with a V-shaped cross section so that the main shaft 32 can be inserted from the direction X orthogonal to the optical axis direction, that is, vertically downward. It forms in the shape which has a pair of wall part 41a, 41a from which a space | interval becomes small toward the side. Here, the lower side in the vertical direction is a direction on one side of the direction orthogonal to the main surface of the pickup base 20, specifically, a direction when the actuator 30 is assembled to the optical pickup device 1. 3, the so-called back surface, which is the surface 20b opposite to the surface 20a facing the optical disk 102 of the pickup base 20, is the direction in the state in which it faces the upper side in the vertical direction. In other words, the first positioning portion 41 is formed with a groove having a concave cross section so that the main shaft 32 can be inserted from the direction X orthogonal to the optical axis direction, and the main shaft 32 is inserted into the concave groove portion. It is formed in such a shape as to have a pair of wall portions 41a, 41a for forming this groove, and is formed so that the distance between them becomes smaller in the direction X.

  The first positioning portion 41 is in a state where the pair of wall portions 41a and 41a are brought into contact with the main shaft 32 so that the position of the main shaft 32 with respect to the pickup base 20 is positioned at a predetermined spatial position. 32 is supported. Here, the first positioning portion 41 is positioned by abutting and positioning the main shaft 32 having a substantially circular cross section by a pair of wall portions 41a, 41a having a V-shaped cross section orthogonal to the optical axis direction. With respect to the spatial position in the cross-sectional direction, particularly fine positioning can be performed.

  Further, the pair of wall portions 41a, 41a are formed in the tangential direction of the cross-sectional shape of the main shaft 32 at the position where the pair of wall portions 41a abut on the main shaft 32, whereby the first positioning portion 41 having the pair of wall portions is The main shaft 32 can be held more securely and the main shaft 32 can be precisely positioned.

  Further, the first positioning portion 41 is provided on one side and the other side of the main shaft 32 in the optical axis direction, and supports one side and the other side of the main shaft 32 in the optical axis direction.

  Further, as shown in FIGS. 6 and 9, the auxiliary shaft 33 of the actuator 30 has a substantially circular cross section orthogonal to the optical axis direction of the collimator lens 26, that is, a cross section orthogonal to the forming direction of the auxiliary shaft 33. Is formed.

  As shown in FIGS. 6 and 9, the second positioning portion 42 is cut out into a substantially rectangular cross section so that the auxiliary shaft 33 can be inserted from the direction X orthogonal to the optical axis direction, like the main shaft 32. It is formed in a concave shape, is formed in a substantially horizontal direction, and has a bottom portion 42a serving as an abutting portion for abutting the auxiliary shaft from the lower side in the vertical direction. Here, the horizontal direction is a plane direction substantially parallel to the main surface of the pickup base 20, and specifically a horizontal plane when the actuator 30 is assembled to the optical pickup device 1. In other words, the second positioning portion 42 is formed with a groove having a concave cross section so that the sub shaft 33 can be inserted from the direction X perpendicular to the optical axis direction, and the sub shaft 33 is formed into the concave groove portion. It is formed in a shape having a bottom surface 42a that has a surface orthogonal to the direction X of inserting the shaft and a contact portion that contacts the auxiliary shaft 33 from the inserting direction.

  The second positioning portion 42 has a substantially circular cross-section from the direction in which the sub-shaft 33 is inserted into the concave portion, that is, the bottom portion 42a substantially orthogonal to the insertion direction of the main shaft 32 and the sub-shaft 33. By positioning the auxiliary shaft 33 in the vertical direction at the time of assembling, which is a predetermined direction with respect to the pickup base 20, the position of the main shaft 32 is positioned by the first positioning portion 41. Fine positioning can be performed so that the posture in the direction around the axis about the main shaft 32 of the actuator 30 is a predetermined posture.

  The second positioning portion 42 is provided on one side of the auxiliary shaft 33 in the optical axis direction and supports one side of the auxiliary shaft 33.

  The second positioning portion 42 and the first positioning portion 41 described above support the actuator 30 at two points by the first positioning portion 41 and the main surface of the actuator 30 by the pair of V-shaped wall portions 41a and 41a. The position of the actuator 30 is supported by a total of three points by restricting the position in a plane parallel to the first position and supporting the actuator 30 by one point by the second positioning unit 42. The collimator lens 26 held by the holding portion 31 of the actuator 30 can be held in an appropriate position.

  In other words, the first and second positioning portions 41 and 42 provided on the pickup base 20 are supported on the main surfaces 20a and 20b of the pickup base 20 by the first positioning portion 41 supporting the main shaft 32 at two points. The position in the so-called height direction, which is orthogonal to the direction, can be adjusted, and the second positioning portion 42 supports the auxiliary shaft 33 at one point, so that the rotational direction is the direction around the axis about the main shaft 32. The position of the actuator 30 and the collimator lens 26 can be held at appropriate positions.

  When the actuator 30 is attached to the pickup base 20, as shown in FIG. 7, the main shaft 32 and the sub shaft 33 of the actuator 30 are formed in the concave shapes of the first and second positioning portions 41 and 42 of the pickup base 20. The actuator is simply inserted into the groove portion formed by so-called throwing-in, that is, the main shaft 32 is inserted into the groove portion of the first positioning portions 41, 41, and the auxiliary shaft 33 is inserted into the groove portion of the second positioning portion 42. Positioning is performed simply by placing 30 on the pickup base 20, and the positioning is performed precisely by pouring adhesive into the concave portions of the first and second positioning portions 41 and 42 in this state. Is integrated.

  In general, an optical element driving unit that drives an optical element such as the collimator lens 26 is required to move the optical element smoothly with a high positional accuracy. The actuator 30 described above can improve the positional accuracy of the collimator lens 26. A minimum lens space position can be secured by the holding portion 31 that holds the lens 26 and the main shaft 32 that is the movement reference axis of the holding portion 31, and the straightness during driving can be provided. This is because the main shaft 32 is positioned in contact with the pair of wall portions 41a provided on each of the first positioning portions 41, 41 provided on both sides in the optical axis direction as described above. This is because the spatial position of the main shaft 32 is fine.

  In the conventional unit structure, the actuator 30 has a main shaft that is press-fitted into the unit base, and the mounting reference as a unit is provided on the side surface, boss, hole, etc. of the base. And the base is also composed of two parts, and the error has increased due to the fact that many tolerances such as assembly tolerances between the two parts are added in a superimposed manner. As shown in FIGS. 6 and 7 and the above description, the main shaft 32 and the sub shaft 33 that serve as a reference when driving the collimator lens 26 and the holding portion 31 that holds the collimator lens 26 protrude from the actuator 30 main body so as to protrude in the axial direction. The first positioning portion 41 which has a pair of wall portions 41a and 41a on the pickup base 20 side and is a V-shaped groove, and a contact serving as a reference for the mounting posture A collimator as an optical element that is easily driven without requiring accuracy for many parts by providing a second positioning portion 42, which is a groove having a bottom portion 42a as a surface, and so-called throwing and bonding thereto. The lens position accuracy and running straightness accuracy of the lens 26 can be increased.

  In the actuator 30 and the pickup base 20 configured as described above, the main shaft 32 and the sub shaft 33 provided in the actuator 30 have a V-shaped cross section provided in the pickup base 20 and have a pair of wall portions 41a and 41a. The position and posture of the actuator 30 with respect to the pickup base 20 are set in a predetermined space by being supported by the first positioning portion 41 and the second positioning portion 42 having a bottom portion 42a for contacting with a concave shape having a substantially rectangular cross section. In this way, by attaching the holding portion 31 that holds the collimator lens 26 with the main shaft 32 as a reference, errors of respective parts and assembly points as in the past are added in a superimposed manner. As a whole, it is possible to prevent a large error from occurring, and the collimator held by the actuator 30 The actuator 30 may be attached to the pickup base 20 in a state of enhanced positional accuracy and running straightness accuracy Tarenzu 26.

  By the way, in the lens holder 12 holding the objective lenses 23 and 24 described above, a tracking coil 51 that generates a driving force in a tracking direction T that is a substantially radial direction of the optical disk, and a focus that is in the direction of approaching and separating from the optical disk. A focus coil 52 that generates a driving force in the direction F is attached.

  The pickup base 20 as an attachment base is provided with a magnet 53 which is disposed so as to face the tracking coil 51 and the focus coil 52 and applies a predetermined magnetic field to the tracking coil 51 and the focus coil 52.

  When a driving current is supplied to the tracking coil 51 and the focus coil 52, the lens holder 12 is moved in the tracking direction by the interaction between the current supplied to the coils 51 and 52 and the magnetic field from the magnet 53. Drive displacement in T and focus direction F.

  As a result, the first and second objective lenses 23 and 24 supported by the lens holder 12 are driven and displaced in the focus direction F and / or the tracking direction T, via the first and second objective lenses 23 and 24. Focus control is performed so that the light beam applied to the optical disc is focused on the signal recording surface of the optical disc, and tracking control is performed so that the light beam follows the recording track formed on the optical disc. Done.

  The optical pickup device 1 configured as described above has the first to third wavelength light beams from the emitting portions provided in the first and second light sources 21 and 22 in accordance with the type of the mounted optical disk. A light beam having a wavelength corresponding to the type of the optical disc is emitted, and the light beam irradiated through the objective lens corresponding to the type of the optical disc among the first and second objective lenses 23 and 24 is a predetermined recording track. By performing focus control and tracking control so as to focus on and follow the information signal, it is possible to record or reproduce an information signal with respect to the optical disc. Then, the optical pickup device 1 drives the actuator 30 according to the type of the optical disk and moves the collimator lens 26 provided in the optical path, so that the optical system for the plurality of types of optical disks as described above. It is possible to reduce aberrations that may occur as a disadvantage of an optical system that realizes multi-wavelength compatibility with a common optical path, thereby realizing good recording / reproducing characteristics.

  An optical pickup device to which the present invention is applied includes a pickup base 20 as a base member provided with at least light sources 21 and 22 and an optical system that guides light beams emitted from the light sources 21 and 22 to the optical disc 102, and An actuator 30 serving as an optical element driving means for driving a collimator lens 26 which is an optical element provided in the optical path of the optical system so as to be movable in the optical axis direction with respect to the pickup base 20. 30 includes a holding portion 31 that holds the collimator lens 26, and a main shaft 32 and a sub shaft 33 that are formed in the optical axis direction and support the holding portion 31 so as to be movable in the optical axis direction. The main shaft 32 is supported so that the position of the main shaft 32 with respect to the pickup base 20 is a predetermined spatial position. The first positioning portion 41 and the auxiliary shaft 33 are supported, and the posture in the direction around the axis about the main shaft 32 of the actuator 30 whose position of the main shaft 32 is positioned by the first positioning portion 41 is a predetermined posture. The first positioning portion 41 and the second positioning portion 42 support the main shaft 32 and the sub-shaft 33, and thereby the actuator 30 for the pickup base 20 is provided. By adjusting the position and posture of the actuator 30 so as to be a predetermined spatial position and posture, the actuator 30 is integrated with the so-called throwing adhesion while being positioned with respect to the pickup base 20, thereby adding an adjustment error in a superimposed manner. As a result, it is possible to prevent a problem such as a large error, and thereby a collimator lens as an optical element. Generation of 6 positional deviation, and this by it is possible to suppress the occurrence of aberrations.

  In other words, the optical pickup device 1 to which the present invention is applied has the above-described configuration, so that the main shaft 32 and the sub shaft 33 of the actuator 30 serving as a guide for moving the collimator lens 26 as an optical element are directly connected. By attaching to the first and second positioning portions 41 and 42 provided on the pickup base 20 to which other optical components are attached, errors of each component and each assembly location as in the past are added in a superimposed manner. As a whole, it is possible to prevent a large error from occurring and improve the positional accuracy of the collimator lens 26 provided in the actuator 30 with a simple configuration.

  In addition, the optical pickup device 1 to which the present invention is applied not only improves the lens position accuracy of the collimator lens 26 and the like held by the actuator 30 as the above-mentioned unit, but also runs as a unit when the actuator 30 feeds the lens. The accuracy and straightness can be improved, and the mounting accuracy to the pickup base 20 can be improved, so that the component accuracy of the actuator 30 as a unit can be relaxed, and the cost can be reduced. The vibration of the motor, which is the drive source attached to the motor, can avoid problems such as the vibration that caused the shaft to vibrate through the base. It is possible to avoid problems such as flange cracking due to screwing, Since it is not necessary to consider base distortion due to characteristics and the reliability is improved, and since accuracy is not required for the base of the actuator 30 itself, an inexpensive press product or the like should be used for the base of the actuator 30. Can reduce costs.

1 is a block circuit diagram showing a schematic configuration of an optical disc apparatus to which the present invention is applied. It is a perspective view which shows the surface side facing the optical disk of the optical pick-up apparatus to which this invention is applied. It is a perspective view which shows the surface side on the opposite side to FIG. 2 of the optical pick-up apparatus to which this invention is applied. It is a perspective view which shows the various optical components which comprise the optical pick-up apparatus to which this invention is applied, the actuator for driving an objective lens, and the actuator for driving an optical element. It is a perspective view for demonstrating the structure of the main axis | shaft and subaxis of an actuator for driving the optical element which comprises an optical pick-up apparatus. It is a disassembled perspective view of the actuator which comprises an optical pick-up apparatus, and the pick-up base for attaching this. It is an expansion perspective view at the time of attaching the actuator which comprises an optical pick-up apparatus to a pick-up base. It is sectional drawing which shows the main axis | shaft of an actuator, and the 1st positioning part of the pick-up base for attaching this. It is sectional drawing which shows the 2nd positioning part of the auxiliary shaft of an actuator, and the pick-up base for attaching this.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Optical pick-up apparatus, 20 Pickup base, 21 1st light source, 22 2nd light source, 23 1st objective lens, 24 2nd objective lens, 25 Beam splitter, 26 Collimator lens, 27 1st raising mirror 28 Second rising mirror, 30 Actuator, 31 Holding unit, 32 Main shaft, 33 Sub shaft, 41 First positioning unit, 42 Second positioning unit, 101 Optical disc device, 102 Optical disc, 103 Spindle motor

Claims (6)

A base member provided with at least a light source and an optical system for guiding a light beam emitted from the light source to an optical disc;
An optical element driving means for driving an optical element provided in the optical path of the optical system so as to be movable in the optical axis direction with respect to the base member;
The optical element driving means includes a holding portion that holds the optical element, and a main shaft and a sub shaft that are formed in the optical axis direction and support the holding portion so as to be movable in the optical axis direction.
The base member supports the main shaft and positions the main shaft so that the position of the main shaft with respect to the base member is a predetermined position. The base member supports the sub shaft and supports the first positioning. A second positioning part is provided for positioning the optical element driving means whose position of the main axis is positioned by a part so that the attitude around the axis about the main axis is a predetermined attitude;
The first positioning unit and the second positioning unit support the main shaft and the sub shaft so that the position and posture of the optical element driving unit with respect to the base member become a predetermined position and posture. Regulated optical pickup device.   The first positioning portions are formed in a concave shape so that the main shaft can be inserted from a direction orthogonal to the optical axis direction, and a distance between the first positioning portions is reduced toward a direction in which the main shaft is inserted into the concave portion. The optical pickup device according to claim 1, wherein the optical shaft is formed in a shape having a pair of wall portions, and supports the main shaft by bringing the pair of wall portions into contact with the main shaft.   The optical pickup according to claim 2, wherein the first positioning portion is provided on one side and the other side of the main shaft in the optical axis direction, and supports one side and the other side of the main shaft in the optical axis direction. apparatus. The main axis is formed such that a cross section perpendicular to the optical axis direction is substantially circular,
The optical pickup device according to claim 2, wherein the pair of wall portions are formed in a tangential direction of a cross-sectional shape of the main shaft at a position in contact with the main shaft.   The second positioning portion is formed in a concave shape so that the auxiliary shaft can be inserted from a direction orthogonal to the optical axis direction, and is in contact with the auxiliary shaft from the direction in which the auxiliary shaft is inserted into the concave portion. The optical pickup device according to claim 2, wherein the optical pickup device is formed in a shape having an abutting portion to be moved. Driving means for holding and rotating the optical disc;
In an optical disc apparatus having an optical pickup device that records and / or reproduces an information signal by irradiating a light beam to an optical disc that is rotationally driven by the driving means.
The optical pickup device includes at least a light source and a base member provided with an optical system that guides a light beam emitted from the light source to an optical disc;
An optical element driving means for driving an optical element provided in the optical path of the optical system so as to be movable in the optical axis direction with respect to the base member;
The optical element driving means includes a holding portion that holds the optical element, and a main shaft and a sub shaft that are formed in the optical axis direction and support the holding portion so as to be movable in the optical axis direction.
The base member supports the main shaft and positions the main shaft so that the position of the main shaft with respect to the base member is a predetermined position. The base member supports the sub shaft and supports the first positioning. A second positioning part is provided for positioning the optical element driving means whose position of the main axis is positioned by a part so that the attitude around the axis about the main axis is a predetermined attitude;
The first positioning unit and the second positioning unit support the main shaft and the sub shaft so that the position and posture of the optical element driving unit with respect to the base member become a predetermined position and posture. Optical disk device to be regulated.

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