JP2008090959A - Optical disk drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk drive with little deterioration of recording and reproduction performance resulting from having adopted a method to switch an objective lense in the optical disk drive having two objective lenses and switching the use objective lense. <P>SOLUTION: Guide members 43, 44 are provided so as to sandwich two guide rails 42a, 42b which hold an optical pickup 4 movably. If the optical pickup 4 moves to a periphery side or an inner periphery side of an optical disk 16, the optical pickup 4 moves to a tangential direction by pressing force from the guide members 43, 44 and switches over the positions of the objectives lense 30, 31. A stopper means 45 is provided at a side face section 4b of the optical pickup 4. The stopper means 45 is provided so that the direction of movement prevention of the optical pickup 4 may be selectively switched. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical disc apparatus that records and reproduces an optical recording medium, and in particular, has two objective lenses for condensing a light beam emitted from a light source on a recording surface of the optical recording medium, and is an object of recording and reproduction. The present invention relates to an optical disc apparatus that uses an objective lens by switching depending on the type of optical recording medium.

  Optical recording media such as compact discs (hereinafter referred to as CDs) and digital versatile discs (hereinafter referred to as DVDs) are widely used. Furthermore, in recent years, in order to increase the amount of information in an optical recording medium, research on increasing the density of the optical recording medium has been promoted. For example, HD-DVD and Blu-ray Disc (hereinafter referred to as BD) which are high-quality DVDs. High-density optical recording media have also been put into practical use.

  An optical disc apparatus that performs recording / reproduction of such an optical recording medium is provided with an optical pickup capable of recording information and reading information by irradiating the optical recording medium with a light beam, depending on the type of the optical recording medium. The numerical aperture (NA) of the objective lens used in the optical pickup and the wavelength of the light source need to be varied. For example, for CD, the NA of the objective lens is 0.45, the wavelength of the light source is 780 nm, for DVD, the NA of the objective lens is 0.60, the wavelength of the light source is 650 nm, and for BD, The NA of the objective lens is 0.85 and the wavelength of the light source is 405 nm.

  As described above, since the NA of the objective lens used and the wavelength of the light source differ depending on the type of optical recording medium, it may be possible to use different optical pickups for each optical recording medium. It is convenient to be able to read information about optical recording media, and many such optical pickups have been developed. Recently, for example, many optical pickup apparatuses that can deal with three types of optical recording media such as CD, DVD, and BD with one objective lens have been proposed.

  However, in the case of a configuration in which one objective lens is used for an optical pickup corresponding to a plurality of types of optical recording media, generally, the design of the objective lens becomes difficult and expensive. Therefore, for example, in an optical pickup of BD / DVD / CD compatible type, there are two objective lenses, one for BD and one for DVD / CD, depending on the type of optical recording medium to be recorded and reproduced. A method of switching and using two objective lenses has been conventionally proposed.

  The objective lens switching method in this case is a configuration in which an objective lens arranged in the optical path is switched by rotating a lens holder on which an objective lens is mounted by an electromagnetic action using a shaft sliding actuator. Depending on the configuration of the optical system, there is a configuration in which an objective lens is selectively used in accordance with an optical recording medium to be recorded and reproduced.

  Patent Document 1 discloses a lens actuator having two objective lenses having different numerical apertures and a lens holder that supports the two objective lenses so as to be aligned in the rotation direction of the optical disc (optical recording medium). There has been proposed an optical disc apparatus that is capable of switching an objective lens by including a lens switching mechanism that moves in the rotation direction.

Patent Document 2 discloses a housing block (with a lens actuator provided therein) in which an objective lens for DVD and an objective lens for CD are arranged in parallel on the upper surface of a sliding block of an optical pickup, An optical system of a type in which the receiving block is slidable in a direction perpendicular to the axis of the guide rail (the optical pickup is slidably supported) and the objective lens is switched by moving the slide of the slide plate Information recording or reproducing devices (optical disc devices) have been proposed.
JP 2004-326887 A JP-A-8-315409

  However, in the configuration in which the objective lens is switched using a shaft sliding type actuator, it is difficult to control the molding of the lens holder part that holds the objective lens, and there is a problem that variations occur during mass production.

  Further, the configurations shown in Patent Document 1 and Patent Document 2 are configurations in which the lens actuator itself is moved to switch the objective lens. In this case, the lens actuator is not firmly fixed to the base of the optical pickup. Therefore, vibration is likely to occur due to the high frequency used when focus adjustment or tracking adjustment of the objective lens is performed, and this vibration causes a problem that the entire optical pickup resonates and servo adjustment cannot be performed properly.

  Furthermore, in the configuration in which the objective lens is selectively used depending on the configuration of the optical system, the above-described problem does not occur, but the position where the light is condensed on the recording surface of the optical recording medium differs for each objective lens. Therefore, the following problems arise. FIG. 8 is a schematic diagram for explaining the problems of the conventional configuration. Hereinafter, the problems will be described with reference to FIG.

  About one objective lens 100, the moving direction (the moving direction of the optical pickup and the moving direction of the objective lens during tracking adjustment correspond) and the moving direction of the optical recording medium 200 at the position of the objective lens are perpendicular to each other. In this case, the angle between the moving direction of the other objective lens 101 (the moving direction of the optical pickup and the moving direction of the objective lens during tracking adjustment) and the moving direction of the optical recording medium 200 at the position of the objective lens is 90 The angle is off from °. In this case, the angle formed by the moving direction of the objective lens 100 and the moving direction of the optical recording medium 200 at the position of the objective lens is 90 ° at any position of the optical recording medium 200. And the moving direction of the optical recording medium 200 at the position of the objective lens differ depending on the position of the optical recording medium 200. In particular, the angle differs between the inner and outer peripheral sides of the optical recording medium (in FIG. 8, The inner peripheral side is indicated by α, and the outer peripheral side is indicated by β, so that α <β. For this reason, when the objective lens 101 is used, the tracking error signal is output differently as the objective lens 101 moves from the inner circumference side to the outer circumference side of the optical recording medium 200, and tracking adjustment cannot be performed properly. There arises a problem that the quality of reproduction or the like of the optical recording medium 200 deteriorates.

  In view of the above problems, an object of the present invention is to provide reproduction and recording performance resulting from adopting a method of switching an objective lens in an optical disc apparatus having two objective lenses and switching the objective lens. To provide an optical disc apparatus with little deterioration.

  To achieve the above object, the present invention provides a base, an optical pickup having two objective lenses for condensing a light beam emitted from a light source on a recording surface of an optical recording medium, and the objective lens so as to sandwich the objective lens. A rod-like member fixed in parallel on the base and supporting the optical pickup so as to be movable in the radial direction of the optical recording medium, and switching the two objective lenses depending on the type of the optical recording medium In the optical disk device to be used, the two objective lenses are arranged in parallel in a direction orthogonal to the rod-shaped member, and a switching mechanism that switches the position of the objective lens by moving the optical pickup in a direction orthogonal to the rod-shaped member. Provided, and the switching mechanism includes two guide members fixed on the base so as to sandwich the two rod-shaped members arranged in parallel from different positions; Stopper means that is attached to the optical pickup and that selectively contacts the movement prevention direction of the optical pickup by providing an abutting portion that abuts on the rod-like member at the first position and the second position. The guide member presses the optical pickup by contact with the optical pickup to move the optical pickup in a direction perpendicular to the rod-shaped member, and the contact portion is configured so that the optical pickup is guided by the optical pickup. The arrangement is switched by being pressed by a member.

  In order to achieve the above object, the present invention sandwiches the objective lens, a base, an optical pickup having two objective lenses for condensing the light beam emitted from the light source on the recording surface of the optical recording medium, and the objective lens. And two rod-like members fixed in parallel on the base and supporting the optical pickup so as to be movable in the radial direction of the optical recording medium, and the two objective lenses depending on the type of the optical recording medium. In the optical disk apparatus that is used by switching, a switching mechanism that switches the position of the objective lens by moving the optical pickup in a direction orthogonal to the rod-shaped member is provided.

  According to the present invention, in the optical disk apparatus having the above-described configuration, the two objective lenses are arranged side by side in a direction orthogonal to the rod-shaped member.

  Further, the present invention provides the optical disc apparatus configured as described above, wherein the switching mechanism includes two guide members fixed on the base so as to sandwich the two rod-shaped members arranged in parallel from different positions; Stopper means for selectively switching the movement prevention direction of the optical pickup by being provided at the first position and the second position so as to be disposed at the first position and the second position. The guide member presses the optical pickup in a direction perpendicular to the rod-shaped member by contact with the optical pickup, and the contact portion is formed by the optical pickup being pressed by the guide member. It is characterized by switching its arrangement.

  According to the first configuration of the present invention, since the entire optical pickup can be moved in the direction orthogonal to the rod-shaped member by the switching mechanism, it is possible to avoid the fact that the condensing position is different because the objective lens to be used is different. For this reason, it is possible to solve the problem of tracking adjustment that has occurred in the past, and to suppress deterioration in reproduction and recording performance due to switching of the objective lens. In addition, since the lens actuator that holds the objective lens can be firmly fixed to the optical pickup, the optical pickup can resonate due to vibration in the lens actuator as in the conventional configuration, which can adversely affect servo adjustment. Low. Furthermore, since the optical pickup is moved in a direction perpendicular to the rod-like member without using an electric member such as a motor, an inexpensive optical disc apparatus can be provided.

  Further, according to the second configuration of the present invention, since the entire optical pickup can be moved in the direction orthogonal to the rod-shaped member by the switching mechanism, it is possible to avoid the fact that the condensing position is different because the objective lens to be used is different. For this reason, it is possible to solve the problem of tracking adjustment that has occurred in the past, and to suppress deterioration in reproduction and recording performance due to switching of the objective lens. In addition, since the lens actuator that holds the objective lens can be firmly fixed to the optical pickup, the optical pickup can resonate due to vibration in the lens actuator as in the conventional configuration, which can adversely affect servo adjustment. Low.

  Further, according to the third configuration of the present invention, in the optical disc apparatus having the second configuration, since the two objective lenses are arranged in parallel to the direction perpendicular to the rod-shaped member, the optical system of the optical pickup is made compact. This makes it easy to reduce the size of the optical disk apparatus.

  According to the fourth configuration of the present invention, in the optical disc apparatus having the second or third configuration, the optical pickup is moved in a direction orthogonal to the rod-shaped member without using an electric member such as a motor. Due to the configuration, an inexpensive optical disc apparatus can be provided.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, embodiment shown here is an example and this invention is not limited to embodiment shown here.

  FIG. 1 is a block diagram showing the configuration of an optical disc apparatus 1 according to this embodiment. The optical disc apparatus 1 is provided so as to be able to reproduce information on an optical disc (optical recording medium) 16 and record information on the optical disc 16. Yes. In the present embodiment, the optical disc apparatus 1 is provided so as to be compatible with BD / DVD / CD.

  Reference numeral 2 denotes a spindle motor, and the optical disk 16 is detachably held on a chuck portion (not shown) provided on the spindle motor 2. Then, when recording / reproducing information on the optical disk 16, the spindle motor 2 continuously rotates the optical disk 16. The rotation control of the spindle motor 2 is performed by the spindle motor control unit 3.

  Reference numeral 4 denotes an optical pickup that irradiates the optical disc 16 with laser light emitted from a light source, thereby enabling writing of information on the optical disc 16 and reading of information recorded on the optical disc 16. FIG. 2 is a schematic diagram showing the configuration of the optical system of the optical pickup 4, FIG. 2A is a schematic side view of the optical pickup 4, and FIG. 2B is a schematic plan view of the optical pickup 4.

  As shown in FIG. 2, the optical pickup 4 includes a first light source 21, a second light source 22, a dichroic prism 23, a collimator lens 24, a beam splitter 25, a first splitter disposed on the optical pickup base 20. Raising mirror 26, second raising mirror 27, condenser lens 28, photodetector 29, first objective lens 30 held by a lens holder of a lens actuator (not shown), and second objective lens 31 .

  The first light source 21 is a laser diode (LD), and emits laser light having a wavelength of 405 nm corresponding to BD. On the other hand, the second light source 22 is a laser diode for two wavelengths, and emits a 650 nm band laser beam corresponding to DVD and a 780 nm band laser beam corresponding to CD. Switching between the first light source 21 and the second light source 22, adjustment of the laser power, and the like are performed by the light source control unit 5.

  In this embodiment, the laser light corresponding to DVD and CD is emitted from the laser diode corresponding to two wavelengths. However, the present invention is not limited to this, and the laser diode that emits laser light corresponding to DVD and CD is used. Of course, it does not matter even if it is a structure provided separately.

  In the optical pickup 4, the laser light (BD laser light) emitted from the first light source 21 passes through the dichroic prism 23, becomes collimated light at the collimating lens 24, passes through the beam splitter 25, and passes through the dichroic mirror. Is transmitted through the first rising mirror 26, which is reflected by the second rising mirror 27 in a direction substantially perpendicular to the recording surface (not shown) of the optical disk 16, and is recorded by the second objective lens 31. Condensed to The reflected light reflected by the recording surface of the optical disc 16 is transmitted through the second objective lens 31, reflected by the second rising mirror 27, transmitted through the first rising mirror 26, reflected by the beam splitter 25, and collected. The light is condensed on a light receiving region (not shown) of the photodetector 29 by the optical lens 28.

  On the other hand, laser light (DVD and CD laser light) emitted from the second light source 22 is reflected by the dichroic prism 23, becomes parallel light by the collimating lens 24, passes through the beam splitter 25, and functions as a dichroic mirror. The light is reflected by the first rising mirror 26 and reflected in a direction substantially orthogonal to the recording surface of the optical disk 16, and is condensed on the recording surface of the optical disk 16 by the first objective lens 30. The reflected light reflected by the recording surface of the optical disc 16 passes through the first objective lens 30, is reflected by the first rising mirror 26, is further reflected by the beam splitter 25, and is reflected by the condenser lens 28. Condensed in a light receiving area (not shown).

  The photodetector 29 converts the optical information contained in the received light beam into an electrical signal. The first objective lens 30 is designed to be used when recording and reproducing DVDs and CDs, and the second objective lens 31 is designed to be used when recording and reproducing BDs. Yes.

  Returning to FIG. 1, the slide motor control unit 6 is electrically connected to a slide motor (not shown) provided so that the optical pickup 4 can move in the radial direction. Controls movement in the radial direction (radial direction).

  The RF signal processing unit 7 processes the RF signal obtained by the photodetector 29 of the optical pickup 4 and supplies the processed signal to the demodulation unit 8.

  The demodulator 8 demodulates the data, detects an error in the data, performs data correction processing if correction is possible when the error is detected, and supplies the reproduction data to the interface unit 9. When a reproduction error that cannot be corrected occurs, data is re-read (retry) by a known method.

  The interface unit 9 outputs the reproduction data supplied from the demodulation unit 8 to an external device such as a personal computer (not shown).

  The focus error signal processing unit 10 generates a focus error signal using a signal detected by the photodetector 29 of the optical pickup 4. Since the generation of the focus error signal is performed by a known method using an astigmatism method, a spot size method, or the like, detailed description thereof is omitted here. The focus error signal generated by the focus error signal processing unit 10 is supplied to the actuator control unit 12.

  The tracking error signal processing unit 11 generates a tracking error signal using a signal detected by the photodetector 29 of the optical pickup 4. Since the generation of the tracking error signal is performed by a known method using a push-pull method, a phase difference method, a collect far field method, or the like, detailed description thereof is omitted here. The tracking error signal generated by the tracking error signal processing unit 11 is supplied to the actuator control unit 12.

  The actuator control unit 12 mounts the objective lenses 30 and 31 on a lens holder based on signals sent from the focus error signal processing unit 10 and the tracking error signal processing unit 11 (not shown). Drive signal). The lens actuator to which the drive signal is supplied operates each part based on the signal, and moves the objective lenses 30 and 31 in a focus direction parallel to the optical axis direction to adjust the focus. Tracking control for adjusting the spot position of the laser beam to the track position formed on the optical disk 16 by moving 31 in the radial direction of the optical disk 16 is performed.

  The lens actuator is configured to drive a lens holder on which the objective lenses 30 and 31 are mounted by electromagnetic action, and is similar to a known lens actuator such as a so-called shaft sliding type or a wire support type. Then, the detailed description is abbreviate | omitted.

  In addition, the overall control unit 15 includes a spindle motor control unit 3, a light source control unit 5, a slide motor control unit 6, an RF signal processing unit 7, a demodulation unit 8, an interface unit 9, a focus error signal processing unit 10, and a tracking error signal processing. The unit 11, the actuator control unit 12, and the storage unit 14 that stores information necessary for control are controlled to control the entire apparatus.

  The outline of the overall configuration of the optical disc apparatus 1 is as described above. In the present embodiment, the optical pickup 4 can be moved in the tangential direction orthogonal to the radial direction (see FIG. 1). As a result, the moving direction of the objective lenses 30 and 31 (this movement is the same as the movement of the optical pickup 4 itself and the lens, regardless of which of the first objective lens 30 and the second objective lens 31 is used). And the movement direction of the optical disk 16 at the objective lens position can be orthogonal to each other, and the track error signal can be output depending on the track position of the optical disk 16. It is possible to avoid the occurrence of defects that are different. Details of this point will be described below.

  FIG. 3 is a schematic plan view of the optical pickup 4 and its periphery viewed from above. FIG. 3 shows a state where the second objective lens 31 is in the use position (a state where BD is recorded / reproduced). The use position refers to the movement direction of the objective lens at the position when the optical pickup 4 moves in the radial direction (this movement is due to movement of the optical pickup 4 itself and movement during tracking adjustment by the lens actuator). And a position where the moving direction of the optical disk at the position of the objective lens is perpendicular to each other (hereinafter, the use position is used in the same meaning as this).

  As shown in FIG. 3, the base 40 is connected to a turntable 41 and can rotate the optical disk 16. The spindle motor 2 is fixed on the base 40 so as to be parallel to the optical pickup 4, and the optical pickup 4 can be moved. And two guide rails 42a and 42b are provided. Since the guide rails 42a and 42b are arranged in parallel with the radial direction (radial direction of the optical disc 16), the optical pickup 4 can move in the radial direction along the guide rails 42a and 42b.

  A rack (not shown) is provided on the side surface portion 4c of the optical pickup 4, and this rack is fitted with a pinion (not shown) attached to an output shaft of a slide motor (not shown). For this reason, the optical pickup 4 can move in the radial direction by the control of the slide motor.

  Further, guide members 43 and 44 are fixed on the base 40 so as to sandwich the two guide rails 42a and 42b. The guide member 43 is disposed on the outer peripheral side of the optical disc 16, and the guide member 44 is disposed on the inner peripheral side of the optical disc 16. Each of the guide members 43 and 44 is formed in a triangular prism shape, and the slope portions 43a and 44a face the side surface portion 4a and the side surface portion 4b of the optical pickup 4, respectively.

  Stopper means 45 for restricting the movement of the optical pickup 4 in the tangential direction (a direction orthogonal to the guide rails 42 a and 42 b) is provided on the side of the side surface portion 4 b of the optical pickup 4. FIG. 4 is a schematic plan view of the optical pickup 4 shown in FIG. 3 viewed from the side surface portion 4b side. As shown in FIG. 4, the stopper means 45 is provided with a V-shaped cross section, and a leaf spring (contact portion) 46 that abuts one surface of the guide rail 42 a and a hollow portion (not shown) provided in the leaf spring 46. , And a rod-like column 47 that supports the leaf spring so as to be rotatable, and a columnar protrusion 48. Note that both the support 47 and the protrusion 48 are fixed to the side surface 4 b of the optical pickup 4.

  In FIG. 4, the stopper means 45 restricts the optical pickup 4 from moving in the right direction. That is, when the optical pickup 4 is about to move in the right direction, the leaf spring 46 is pushed by the guide rail 42a to rotate in the left direction, but this rotation is restricted by the protrusion 48. For this reason, the movement of the optical pickup 4 in the tangential direction (see FIG. 3) is normally restricted. However, when the force from the guide rail 42a pushing the leaf spring 46 exceeds a certain force, the leaf spring 46 can move to the other position beyond the projection 48 due to the deformation of the distal end portion 46a side of the leaf spring 46. It has become.

  An operation for switching the use positions of the objective lenses 30 and 31 in the case of recording / reproducing a BD and the case of reproducing a DVD / CD with the above configuration will be described. Here, a case where the first objective lens 30 is moved from the state where the second objective lens 31 is in the use position (for example, the state where BD is recorded and reproduced in the state of FIG. 3) to the use position will be described as an example. The description will be made with reference to FIGS. FIG. 5 is a diagram for explaining a state in which the optical pickup moves in the tangential direction, and FIG. 6 is a diagram showing a state in which the leaf spring constituting the stopper means has moved from the first position to the second position. It is.

  When the first objective lens 31 is moved to a use position (a state in which a DVD or CD is recorded / reproduced), a command is issued from the overall control unit 15 (see FIG. 1) to the slide motor control unit 6 (see FIG. 1). The optical pickup 4 starts to move toward the outer periphery side of the optical disc 16 (right direction in FIG. 3). When the optical pickup 4 moves to the outer peripheral side, the optical pickup 4 and the guide member 43 come into contact at a certain point.

  When the optical pickup 4 is further moved to the outer peripheral side from this state, the surface 43a of the guide member 43 that comes into contact with the optical pickup 4 becomes an inclined surface, so that the pressing force in the direction of the broken line arrow shown in FIG. In addition, the optical pickup 4 moves in the tangential direction (lower side in FIG. 5). Thereby, the 1st objective lens 30 is arrange | positioned in a use position.

  In this case, since the optical pickup 4 moves in the right direction in FIG. 4, a strong leftward force is applied to the leaf spring 46 from the guide rail 42a, and the tip end portion 46a of the leaf spring 46 is greatly deformed. Therefore, the leaf spring 46 gets over the protrusion 48 and rotates to the left, and moves from the first position to the second position indicated by the broken line in FIG. In this second position, the leaf spring 46 abuts against the guide rail 42a on a surface different from that in the first position. When the leaf spring 46 is arranged at the second position, the optical pickup 4 tries to move in the left direction in FIG. 6, and even if a force is applied from the guide rail 42a to the leaf spring 46, the force is constant. Otherwise, the rightward rotation of the leaf spring 46 is restricted by the protrusion 48. For this reason, the leftward movement of the optical pickup 4 is restricted by the stopper means 45.

  When switching from the state in which the first objective lens 30 is in the use position to the state in which the second objective lens 31 is in the use position, the optical pickup 4 can be moved to the inner peripheral side in the same manner as described above. Switching can be performed.

  In the present embodiment described above, the guide members 43 and 44 are arranged on the outer peripheral side and the inner peripheral side of the optical disc 16, but the present invention is not limited to this. For example, the guide members 43 and 44 are not limited thereto. These may be arranged on the outer peripheral side or the inner peripheral side. However, it is necessary to arrange the guide member 43 and the guide member 44 at a position shifted from the line-symmetric position.

  In this embodiment, the optical pickup 4 is moved in the tangential direction using the guide members 43 and 44. However, the present invention is not limited to this configuration and does not depart from the object of the present invention. Various changes can be made within the range. For example, as shown in FIG. 7, a rack 50 is provided on the side surface portion 4 a of the optical pickup 4, and the stepping provided on the base 40 when the optical pickup 4 moves to the outer peripheral side (right side in FIG. 7) of the optical disk 16. The pinion 52 attached to the output shaft 51 a of the motor 51 may be fitted, and the optical pickup 4 may be moved in the tangential direction by the rotation control of the stepping motor 51. Further, a configuration may be adopted in which a solenoid is provided so as to sandwich the guide rails 42a and 42b, and the optical pickup 4 is moved in the tangential direction using the solenoid.

  Further, the configuration of the stopper means 45 that restricts the movement of the optical pickup 4 in the tangential direction is not limited to the configuration of the present embodiment, and various modifications may be made without departing from the object of the present invention. I do not care. For example, the protrusion 48 in the present embodiment may be constituted by an elastic member, or the upper end side of two surfaces formed by the V-shape of the leaf spring 46 is bent to increase the strength of the leaf spring 46. It doesn't matter.

  Furthermore, in the present embodiment, the optical system of the optical pickup 4 is configured to use a partly common optical path for the BD and the DVD / CD, but the BD optical system and the DVD / CD optical system are used. An optical path that is common to the system may not be provided, and two different optical systems may be arranged. In this case, the first objective lens 30 and the second objective lens 31 are not juxtaposed in the tangential direction as in the present embodiment, and can be arranged at positions shifted in both the tangential direction and the radial direction. It is.

  In addition, in this embodiment, the optical disk 16 targeted by the optical disk apparatus 1 is BD / DVD / CD, but the present invention is not limited to this, and the present invention can also be applied to optical disk apparatuses targeted for other optical disks. Needless to say.

  The optical disc apparatus of the present invention employs a configuration in which two objective lenses are switched and used, but there is little deterioration in reproduction performance due to the configuration in which the objective lenses are switched and used. For this reason, it is useful as an optical disk apparatus that switches between two objective lenses.

These are block diagrams which show the structure of the optical disk apparatus of this embodiment. These are the schematic which shows the structure of the optical system of the optical pick-up of this embodiment. These are the schematic plan views which looked at the optical pick-up and its periphery from the top. FIG. 4 is a schematic plan view when the optical pickup shown in FIG. 3 is viewed from the side surface side. These are explanatory drawings for explaining how the optical pickup moves in the tangential direction. These are figures which show the state which the leaf | plate spring which comprises a stopper means moved from the 1st position to the 2nd position. These are figures which show the modification of the optical disk apparatus of this invention. These are the schematic diagrams for demonstrating the problem of the conventional structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk apparatus 4 Optical pick-up 16 Optical disk (optical recording medium)
21 1st light source 22 2nd light source 30 1st objective lens 31 2nd objective lens 40 Base 42a, 42b Guide rail (bar-shaped member)
43, 44 Guide member 45 Stopper means 46 Leaf spring (contact portion)

Claims (4)

Base and
An optical pickup having two objective lenses for condensing the light beam emitted from the light source on the recording surface of the optical recording medium;
Two rod-like members fixed in parallel on the base so as to sandwich the objective lens, and supporting the optical pickup movably in the radial direction of the optical recording medium;
In an optical disc apparatus that uses the two objective lenses by switching according to the type of the optical recording medium,
The two objective lenses are juxtaposed in a direction perpendicular to the rod-shaped member,
A switching mechanism for switching the position of the objective lens by moving the optical pickup in a direction orthogonal to the rod-shaped member is provided,
The switching mechanism is
Two guide members fixed on the base so as to sandwich the two rod-shaped members arranged in parallel from different positions;
Stopper means for selectively switching the movement prevention direction of the optical pickup by being provided at the first position and the second position so as to be disposed at the first position and the second position. ,
Consisting of
The guide member moves the optical pickup in a direction orthogonal to the rod-shaped member by pressing the optical pickup by contact with the optical pickup,
The optical disk apparatus according to claim 1, wherein the contact portion switches its arrangement when the optical pickup is pressed by the guide member. Base and
An optical pickup having two objective lenses for condensing the light beam emitted from the light source on the recording surface of the optical recording medium;
Two rod-like members fixed in parallel on the base so as to sandwich the objective lens, and supporting the optical pickup movably in the radial direction of the optical recording medium;
In an optical disc apparatus that uses the two objective lenses by switching according to the type of the optical recording medium,
An optical disc apparatus comprising a switching mechanism for moving the optical pickup in a direction orthogonal to the rod-shaped member to switch the position of the objective lens.   The optical disc apparatus according to claim 2, wherein the two objective lenses are arranged side by side in a direction orthogonal to the rod-shaped member. The switching mechanism is
Two guide members fixed on the base so as to sandwich the two rod-shaped members arranged in parallel from different positions;
Stopper means for selectively switching the movement prevention direction of the optical pickup by providing a contact portion attached to the optical pickup and capable of being arranged at the first position and the second position. When,
Consisting of
The guide member presses the optical pickup in a direction perpendicular to the rod-shaped member by contact with the optical pickup,
4. The optical disk apparatus according to claim 2, wherein the contact portion switches its arrangement when the optical pickup is pressed by the guide member.

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