JP3899568B2 - Optical pickup - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical pickup used for recording and reproduction on an optical disk such as a high-density disk or a compact disk.
[0002]
[Prior art]
A conventional optical pickup for recording / reproducing a high-density recording disk and a compact disk will be described below. FIG. 7 is a front view of a conventional optical pickup unit, and FIG. 8 is a DD sectional view of FIG.
[0003]
Reference numeral 130 denotes a volume for adjusting the amount of laser light emitted from the semiconductor laser in the optical unit 121, and is mounted on a laser substrate 160 fixed on the optical unit 121 by means such as soldering. Reference numeral 131 denotes a volume for adjusting the amount of laser light emitted from the semiconductor laser in the optical unit 123. It is mounted on a laser substrate 161 fixed on the optical unit 123 by means such as soldering. Reference numeral 132 denotes a superimposing circuit for superimposing the semiconductor laser light in the optical unit 121.
[0004]
The optical units 121 and 123 configured as described above need to be rotationally adjusted in the φ direction and the ψ direction, respectively. Therefore, the arms 162 and 163 for adjusting the rotation as the adjusting equipment and the rotating arms 164 and 165 are provided for adjusting the rotation drive mechanism and the volumes 130 and 131, respectively. Further, when the optical units 121 and 123 are rotated and adjusted, the volumes 130 and 131 are also rotated. Therefore, the rotating arm 164 and the rotation driving device are on the arm 162 to be rotated, and the rotating arm 165 and the rotation drive are on the arm 163 to be rotated. The device is configured.
[0005]
[Problems to be solved by the invention]
However, in the configuration of the conventional optical pickup, since the adjustment equipment for adjusting the rotation and volume of the optical unit is adjusted from the same plane, the optical unit cannot be brought close to the volume, and the optical pickup can be downsized. I can't. Further, since volume adjustment is necessary for adjusting the rotation of the optical unit, there is a problem that adjustment equipment is complicated and equipment costs increase.
[0006]
SUMMARY OF THE INVENTION An object of the present invention is to provide an optical pickup that is thin and easy to adjust.
[0007]
[Means for Solving the Problems]
  The optical pickup of the present invention isA first light source, an optical member that transmits the first emitted light emitted from the first light source, an objective lens that converges the first emitted light transmitted through the optical member, and the first emitted light A second light source that enters the optical member from a right angle direction and emits light guided on the same optical path as the first emitted light, a carriage that mounts the first light source and the second light source, and a first First adjusting means for adjusting the light amount of the light source, and second adjusting means for adjusting the light amount of the second light source, wherein the first adjusting means and the second adjusting means are arranged on the side surface of the carriage. , Being arranged on a surface located on the second light source side with respect to the optical axis of the first outgoing light.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
  The invention according to claim 1 is a first light source;An optical member for transmitting the first outgoing light emitted from the first light source, an objective lens for converging the first outgoing light transmitted through the optical member, and the optical member from a direction perpendicular to the first outgoing light A second light source that emits light that enters the light and is guided on the same optical path as the first emitted light;A carriage on which the first light source and the second light source are mounted;Light intensityA first adjusting means for adjusting and a second light sourceLight intensitySecond adjusting means for adjusting,The first adjusting means and the second adjusting means are arranged on a surface located on the second light source side with respect to the optical axis of the first emitted light on the side surface of the carriage. The first light source is provided by disposing the first adjustment unit and the second adjustment unit on the side surface of the carriage that is located on the second light source side with respect to the optical axis of the first emitted light. Since the distance connecting each of the optical unit, the optical unit provided with the second light source, the first adjusting means, and the second adjusting means can be shortened, the area of the connection cable connecting them can be reduced. Can do. As a result, since the area of the connection cable exposed on the surface of the carriage facing the optical disk or on the back surface thereof can be reduced, disconnection due to the bending of the connection cable that changes as the carriage moves can be prevented. Further, by arranging the first adjusting means and the second adjusting means on the same surface, the position of the jig used when adjusting the light amount of the first adjusting means and the light amount adjustment of the second adjusting means. Since the position of the jig used when performing the adjustment can be brought closer, the jig used when adjusting the light quantity of the first adjusting means and the jig used when adjusting the light quantity of the second adjusting means are combined. And the movement distance can be shortened. As a result, the first adjustment means and the second adjustment means can be adjusted with the same small equipment, and the time for moving the jig can be shortened, so that the productivity can be improved and the equipment configuration can be simplified. Cost can be reduced. Furthermore, by adjusting the light amount of the first light source with the first adjusting means and adjusting the light amount of the second light source with the second adjusting means, the light amount adjustment of each light source can be adjusted independently, The amount of light in the first light source and the second light source can be reliably adjusted with almost no error.
[0009]
  The invention described in claim 2The surface located on the second light source side from the optical axis of the first emitted light is adjacent to at least one of the surface on which the first light source is disposed or the surface on which the second light source is disposed. It is characterized by being. The surface located on the second light source side with respect to the optical axis of the first outgoing light is adjacent to either the surface on which the first light source is disposed or the surface on which the second light source is disposed. By being a surface, at least one of the surface located on the second light source side from the optical axis of the first outgoing light, the surface on which the first light source is disposed, or the surface on which the second light source is disposed Since the surface of the light source is not the same surface, the light amount of the light source is also adjusted while adjusting the rotation direction of the optical unit (adjusting the polarization plane of the laser light emitted from the optical unit in a predetermined direction). be able to. Further, the surface located on the second light source side from the optical axis of the light emitted from the first light source is at least one of the surface on which the first light source is disposed and the surface on which the second light source is disposed. The surface adjacent to the surface of the first light source, the surface located on the second light source side from the optical axis of the first outgoing light, and the surface on which the first light source is disposed or the second light source are disposed. At least one of the two surfaces other than the same surface can be made closest, so that the optical unit provided with the first light source, the optical unit provided with the second light source, the first adjusting means, Since the distance connecting each of the two adjusting means can be shortened, the area of the connection cable connecting them can be further reduced. As a result, the area of the connection cable exposed on the surface of the carriage facing the optical disk or the back surface thereof can be reduced, so that disconnection due to the bending of the connection cable that changes as the carriage moves can be efficiently prevented. .
[0010]
  The invention according to claim 3The surface on which the first adjusting means and the second adjusting means are arranged isIt is different from both the surface on which the first light source is disposed and the surface on which the second light source is disposed.It is characterized by. ThisDuring the adjustment of the rotation direction of the optical unit, the output of the semiconductor laser can be adjusted. That is, since two operations can be performed simultaneously at the same time, the operation time required for assembling the optical pickup can be shortened, and the manufacturing cost can be reduced.
[0011]
  According to a fourth aspect of the present invention, there is provided a pickup capable of reproducing the first recording medium and the second recording medium having different recording densities, a first light source for irradiating light on the first recording medium, A first optical unit comprising a first light receiving means for receiving light emitted from one light source and reflected by a first recording medium; a first optical unit comprising a first light source and a first light receiving means;An optical member for transmitting the first outgoing light emitted from the first light source, an objective lens for converging the first outgoing light transmitted through the optical member, and the optical member from a direction perpendicular to the first outgoing light A second light source that emits light that enters the light and is guided on the same optical path as the first emitted light;A second optical unit comprising a second light receiving means for receiving light emitted from the second light source and reflected by the second recording medium; a second optical unit comprising a second light source and a second light receiving means; A carriage on which the first optical unit and the second optical unit are mounted; a first adjustment unit that adjusts the first light source; and a second adjustment unit that adjusts the second light source.The first adjusting means and the second adjusting means are arranged on a surface located on the second light source side with respect to the optical axis of the first emitted light on the side surface of the carriage. The first light source is provided by disposing the first adjustment unit and the second adjustment unit on the side surface of the carriage that is located on the second light source side with respect to the optical axis of the first emitted light. Since the distance connecting each of the optical unit, the optical unit provided with the second light source, the first adjusting means, and the second adjusting means can be shortened, the area of the connection cable connecting them can be reduced. Can do. As a result, since the area of the connection cable exposed on the surface of the carriage facing the optical disk or on the back surface thereof can be reduced, disconnection due to the bending of the connection cable that changes as the carriage moves can be prevented. Further, by arranging the first adjusting means and the second adjusting means on the same surface, the position of the jig used when adjusting the light amount of the first adjusting means and the light amount adjustment of the second adjusting means. Since the position of the jig used when performing the adjustment can be brought closer, the jig used when adjusting the light quantity of the first adjusting means and the jig used when adjusting the light quantity of the second adjusting means are combined. And the movement distance can be shortened. As a result, the first adjustment means and the second adjustment means can be adjusted with the same small equipment, and the time for moving the jig can be shortened, so that the productivity can be improved and the equipment configuration can be simplified. Cost can be reduced. Furthermore, by adjusting the light amount of the first light source with the first adjusting means and adjusting the light amount of the second light source with the second adjusting means, the light amount adjustment of each light source can be adjusted independently, The amount of light in the first light source and the second light source can be reliably adjusted with almost no error.
  According to a fifth aspect of the present invention, there is provided a first connection unit that electrically connects a first terminal group provided in the first optical unit and the first adjustment unit, and the second optical unit. A second connecting means provided in the unit for electrically connecting the second terminal group and the second adjusting means, wherein the first connecting means and the second connecting means are one flexible; By forming the printed circuit, it is possible to suppress the occurrence of bending or bending of the FPC due to the operation of the carriage, so that a highly reliable optical pickup with less occurrence of malfunction such as disconnection or winding can be obtained.
[0012]
  The invention described in claim 6The surface located on the second light source side with respect to the optical axis of the first outgoing light is adjacent to either the surface on which the first light source is disposed or the surface on which the second light source is disposed. It is a surface. The surface located on the second light source side with respect to the optical axis of the first outgoing light is adjacent to either the surface on which the first light source is disposed or the surface on which the second light source is disposed. By being a surface, at least one of the surface located on the second light source side from the optical axis of the first outgoing light, the surface on which the first light source is disposed, or the surface on which the second light source is disposed Since the surface of the light source is not the same surface, the light amount of the light source is also adjusted while adjusting the rotation direction of the optical unit (adjusting the polarization plane of the laser light emitted from the optical unit in a predetermined direction). be able to. Further, the surface located on the second light source side from the optical axis of the light emitted from the first light source is at least one of the surface on which the first light source is disposed and the surface on which the second light source is disposed. The surface adjacent to the surface of the first light source, the surface located on the second light source side from the optical axis of the first outgoing light, and the surface on which the first light source is disposed or the second light source are disposed. At least one of the two surfaces other than the same surface can be made closest, so that the optical unit provided with the first light source, the optical unit provided with the second light source, the first adjusting means, Since the distance connecting each of the two adjusting means can be shortened, the area of the connection cable connecting them can be further reduced. As a result, the area of the connection cable exposed on the surface of the carriage facing the optical disk or the back surface thereof can be reduced, so that disconnection due to the bending of the connection cable that changes as the carriage moves can be efficiently prevented. .
[0013]
  The invention described in claim 7The surface on which the first adjusting means and the second adjusting means are arranged isIt is different from both the surface on which the first light source is disposed and the surface on which the second light source is disposed.It is characterized by. ThisDuring the adjustment of the rotation direction of the optical unit, the output of the semiconductor laser can be adjusted. That is, since two operations can be performed simultaneously at the same time, the operation time required for assembling the optical pickup can be shortened, and the manufacturing cost can be reduced.
[0014]
In the invention described in claim 8, by setting the distance between the first adjusting means and the second adjusting means to be within 10 mm, the jig operating distance can be further shortened and the adjusting equipment can be further downsized.
[0015]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a front view of an optical pickup according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a disk. In this embodiment, a disk 1 is a high-density disk 1a such as a digital video disk (hereinafter abbreviated as DVD) or a low-density disk 1b such as a compact disk (hereinafter abbreviated as CD). Used. Here, the high-density disk 1a is, for example, a disk having a structure in which two substrates having a recording layer are prepared and the two substrates are bonded together. A spindle motor unit 2 for rotating the disk 1 will be described in detail later, and has a mechanism for clamping the disk 1. Reference numeral 3 denotes an optical pickup unit for recording / reproducing on / from the disk 1, which will be described in detail later. A feed unit 4 moves the optical pickup unit 3 to the inner periphery and the outer periphery. Reference numeral 5 denotes a module base on which a spindle motor unit, an optical pickup unit, and a feed unit are mounted. Reference numerals 6 and 7 denote flexible substrates that supply power to the spindle motor and the optical pickup unit.
[0016]
FIG. 2 is a front view of a spindle motor unit according to an embodiment of the present invention, FIG. 3 is a cross-sectional view taken along line AA of FIG. 2 in the embodiment of the present invention, and FIG. FIG. 5 is a front view of the pickup, FIG. 5 is a BB sectional view of FIG. 4 in one embodiment of the present invention, and FIG. 6 is a CC sectional view of FIG. 4 in one embodiment of the present invention.
[0017]
2 to 3, 8 is a disk-shaped turntable for accurately positioning the disk 1, 9 is a ring-shaped permanent magnet, and the permanent magnet 9 alternately forms N magnetic poles and S magnetic poles on the circumference. ing. For example, S magnetic poles are arranged between four N magnetic poles, and the angles between the magnetic poles are arranged at intervals of about 45 degrees. In this case, there are eight magnetic poles. In the present embodiment, the number of magnetic poles is set to 8, but it is preferable that the number of magnetic poles is in the range of 4 to 16. If the number of magnetic poles is 3 or less, stable rotation cannot be obtained. If the number of magnetic poles is 13 or more, the magnetic force when magnetized becomes too small, and it is difficult to obtain stable rotation.
[0018]
A sheet metal 10 is used as a yoke for the permanent magnet 9. The sheet metal 10 is fixed to the turntable 8 by means such as adhesion or integral molding. At this time, a plate-like body made of a ferromagnetic material may be used instead of the sheet metal 10. In this embodiment, the sheet metal 10 is provided to increase the magnetic force of the permanent magnet 9, but the sheet metal 10 may not be provided if the magnetic force of the permanent magnet 9 is not so much required.
[0019]
Further, the permanent magnet 9 and the sheet metal 10 may be formed integrally, or the turntable 8, the permanent magnet 9, and the sheet metal 10 may be formed integrally. By integrating the three members in this way, the members can be reduced in size and the apparatus can be reduced in thickness.
[0020]
Reference numeral 11 denotes a spindle coil configured by arranging a plurality of coil groups in an annular shape. The spindle coil 11 is formed of a number of coils facing the permanent magnet 9 and different from the number of magnetic poles of the permanent magnet 9. At this time, it is preferable to make the number of coils smaller than the number of magnetic poles of the permanent magnet 9. Each of the coil groups has a substantially triangular shape, and the opposing coils are connected in series. In the present embodiment, since the number of magnetic poles of the permanent magnet 9 is 8, the spindle coil 11 is configured by arranging six coils in an annular shape. In the present embodiment, six coils are arranged in a ring shape, but it is preferable that the coils are configured in the range of 4 to 12.
[0021]
Reference numeral 12 denotes a base sheet metal used as a counter yoke of the permanent magnet 9, and a diaphragm having a partially tapered surface is provided near the center. Further, a metal housing 13 is fixed to the aperture portion by means such as caulking, and the metal housing 13 stands upright with respect to the base sheet metal 12. At this time, the base sheet metal 12 is made of sheet metal, but may be made of a plate-like body made of a ferromagnetic material. A spindle coil 11 is disposed on the base sheet metal 12 via a flexible printed board (not shown). This flexible printed circuit board (not shown) has a predetermined wiring structure, and this wiring and the spindle coil 11 are electrically connected, and a current flows through the spindle coil 11 so that the turntable 8 rotates.
[0022]
14 is an impregnated metal, and the impregnated metal 14 is fixed inside the metal housing 13 by means such as thick insertion. Since the impregnated metal 14 is small in size and has very good lubricity and low friction, the impregnated metal 14 is particularly suitable for a thin drive. In this embodiment, the impregnated metal 14 is disposed at both ends inside the metal housing 13, but at least one impregnated metal or three or more impregnated metals are disposed in the metal housing 13 in consideration of the use environment. May be. Furthermore, although the impregnated metal is used in the present embodiment, other bearings may be used.
[0023]
Reference numeral 15 denotes a spindle shaft. The spindle shaft 15 has an end surface on a spherical surface and the other end surface is thickly fixed to the turntable 8.
[0024]
Reference numeral 16 denotes a deformed ball for clamping the disk 1, and the deformed ball 16 is always urged toward the outer periphery of the disk 1 by a clamp spring 17. Due to this urging force, the disk 1 is always clamped by applying a pressure ga to the turntable 8 side. Further, when the disk 1 is removed, the deformed ball 16 is removed while compressing the clamp spring 17 toward the inner peripheral side of the disk 1.
[0025]
The module base 5 is formed with a substantially circular module base hole 5a into which the narrowed portion of the base sheet metal 12 is inserted. The base sheet metal 12 is tangential within the module base hole 5a within the range of the module base hole 5a. And can be skewed in the radial direction. That is, the spindle shaft 15 is erected at a predetermined angle with respect to the module base 5 at the time of manufacture. With this configuration, the disk 1 can be skewed in the tangential and radial directions. That is, by performing the adjustment as described above, the distance between the disk 1 and the optical pickup can be made substantially constant, and good reproduction can be performed.
[0026]
Reference numeral 18 denotes a skew spring, and 19 denotes a fixing screw through which the skew spring 18 is inserted and fixed to the module base 5 through the base sheet metal 5. The skew spring 18 is fixed to a fixing screw 19 so as to sandwich the base sheet metal 12 together with the module base 5, and the skew spring 18 biases the base sheet metal 12 toward the module base 5.
[0027]
Reference numerals 20a and 20b denote adjustment screws for skewing the base metal plate 12 in the radial direction and the tangential direction with respect to the module base 5, and the skew adjustment is performed by tightening or loosening the adjustment screws. The adjusting screws 20 a and 20 b penetrate the module base 5 and are screwed into the base metal plate 12. In the skew adjustment, first, the skew spring 18 is inserted into the fixing screw 19, and the fixing screw 19 is passed through the base metal plate 12 to fix the fixing screw 19 to the module base 5. With this configuration, the skew spring 18 biases the base sheet metal 12 toward the module base 5 as described above. Next, the skews of the sheet metal base 12 with respect to the module base 5 in the radial direction and the tangential direction are adjusted by rotating the adjusting screws 20a and 20b. At this time, since the base sheet metal 12 is fixed to the module base 5 with the fixing screw 19, it seems that the base sheet metal 12 does not displace by rotating the adjusting screws 20a and 20b. Therefore, the base sheet metal 12 can be displaced within a certain range.
[0028]
In the following, an optical pickup capable of reproducing a plurality of different types of discs will be described by taking a DVD as the high-density disc 1a and a CD as the low-density disc 1b.
[0029]
4 to 6, reference numeral 21 denotes an optical unit. The optical unit 21 receives a semiconductor laser that emits a laser beam 22 having a wavelength of 635 to 650 nm for reproducing the high-density disk 1a, and reflected light from the high-density disk 1a. A diffraction grating (not shown) that leads to a detector and a photodetector (not shown) that includes a plurality of light receiving elements that receive light from the diffraction grating are integrally configured.
[0030]
Reference numeral 23 also denotes an optical unit, which includes a semiconductor laser that emits a laser beam 24 having a wavelength of 780 nm for reproducing the low-density disc 1b, a diffraction grating that generates three beams from the laser beam 24, and a low-density disc 1b. A diffraction grating (not shown) that guides reflected light from the detector to a detector and a photodetector (not shown) that includes a plurality of light receiving elements that receive light from the diffraction grating are integrated. is there.
[0031]
By using the optical unit 21 and the optical unit 23 integrated in this way for the optical pickup, the optical axis adjustment and the like that have been performed for each optical member until now can be performed on a unit basis. The number and time can be greatly reduced. Unlike the adjustment of each small optical member, it can be adjusted in units, so that handling during adjustment is greatly improved, and more accurate installation is possible, and positional deviation during installation is possible. The occurrence of can also be greatly reduced.
[0032]
In addition, since one optical unit is provided for each semiconductor laser, each optical unit can be optimally arranged according to each semiconductor laser, and further, each can perform optimum focus / tracking adapted to the disc to be reproduced. Separate diffraction gratings having different shapes can be provided for each unit, and in addition, the detection means is formed in advance so as to form an RF signal and a focus tracking signal that are used as the optimum method for each disk. Therefore, it is possible to realize an optical disc apparatus with good performance capable of detecting a signal and controlling a pickup with very high accuracy.
[0033]
The light source unit 21 and the light source unit 23 are arranged so that the optical axis of the laser light 22 emitted from the optical unit 21 and the laser light 24 emitted from the optical unit 23 are substantially orthogonal to each other. The center of the beam splitter 25 that substantially reflects the laser beam 22 and substantially transmits the laser beam 24 is the intersection of the optical axis of the laser beam 22 from the optical unit 21 and the optical axis of the laser beam 24 from the optical unit 23. It arrange | positions on the plane which contains, and is comprised so that the light radiate | emitted from the different position may be guide | induced on the substantially same optical axis.
[0034]
Since the light from the semiconductor lasers arranged at different positions is arranged on substantially the same optical axis, the optical member after being guided on the same optical axis can be shared. It is possible to reduce the number of parts of the optical members such as productivity, and to improve productivity and reduce production costs. In addition, since the optical path is shared, there are almost common factors that deteriorate optical characteristics such as aberration generated in the light emitted from each semiconductor laser. The magnitudes of aberrations and the like before the light enters the objective lens 29 can be made substantially equal. Accordingly, the light from the plurality of semiconductor lasers can be more easily converged on the optical disc 1 by the single objective lens 29.
[0035]
Further, a wavelength filter 26 is disposed on the light exit surface 25 a side of the beam splitter 25. The wavelength filter 26 has a transmission region that transmits light of any wavelength and a selective transmission region that blocks light of a specific wavelength. In particular, in the present embodiment, the transmission region is a region that transmits both the laser light 22 irradiated to the high-density disk and the laser light 24 irradiated to the low-density disk, and the selective transmission region is the high-density disk 1a. The laser beam 22 to be irradiated is substantially transmitted and the laser beam 24 to be irradiated to the low density disk 1b is hardly transmitted. The shape of the selective transmission region is that the laser beam 24 to be irradiated to the low density disk 24 is the objective lens. It is formed so as to realize a shape required when entering the light 29. In the present embodiment, specifically, the objective lens is formed to have a numerical aperture of 0.43 to 0.45.
[0036]
The wavelength filter 26 is formed using a dielectric material, and is formed of a separate member from the beam splitter 25 by alternately combining a dielectric material having a high refractive index and a dielectric material having a low refractive index. In some cases, it is often formed on a base material such as optical glass. And it fixes to the light-projection surface 25a of the beam splitter 25 by means, such as adhesion | attachment. It is also conceivable to form in advance on the beam splitter 25. In this case, the surface which becomes the light emitting surface 25a of the substrate at the stage of the substrate before forming the prism having the light emitting surface 25a of the beam splitter 25. A dielectric film is directly formed in advance by a method such as sputtering or vapor deposition.
[0037]
In particular, when the optical filter is formed in advance, the optical member mounting process can be reduced, so that an optical pickup with high productivity can be obtained, and an adhesive layer formed when the wavelength filter 26 is provided on the beam splitter 25. Since the deterioration of the optical characteristics due to the presence of can be suppressed, particularly good optical characteristics can be realized.
[0038]
The wavelength filter 26 can be disposed anywhere between the beam splitter 25 and the objective lens 29, and the desired effect can be obtained.
[0039]
The laser beam 22 and the laser beam 24 that have passed through the wavelength filter 26 are incident on a collimator lens 27 that is provided as necessary, and the divergent light is converted into light having a smaller divergence or substantially parallel light and is provided in the suspension holder 40. The optical axis direction is changed by the rising mirror 28 and is focused on the optical disc 1 by the objective lens 29. Here, the objective lens 29 condenses the light on the recording surface of the high-density disk 1a when the laser light 22 is incident, and records the light on the recording surface of the low-density disk 1b when the laser light 24 is incident. It is formed so as to be condensed. In the present embodiment, the objective lens 29 has a numerical aperture of 0.6 so that the laser beam 22 having a wavelength of 635 to 650 nm is condensed on the recording surface of a DVD formed with a substrate thickness of 0.6 mm. Thus, the laser beam 22 is condensed to about 1 μm. The objective lens 29 is set so that the laser beam 24 having a wavelength of about 780 nm transmitted through the wavelength filter 26 is condensed on the recording surface of the CD formed with a substrate thickness of 1.2 mm. As a result, the laser beam 24 is condensed to about 1.2 to 1.5 μm.
[0040]
Thus, by using the wavelength filter 26 and the objective lens 29 in combination, the shape of the incident light at the objective lens 29 is optimized, and the condensing position and the size of the condensing spot corresponding to each optical disc 1 are set. Since it is realizable, it becomes possible to condense the light of a several semiconductor laser on the optical disk 1 from which a kind differs using one objective lens.
[0041]
The arrangement of the optical unit 21 is set so that the position of the semiconductor laser provided for reproduction of the high-density disk 1a provided in the unit becomes substantially parallel light after passing through the collimator lens 27, and the arrangement of the optical unit 23 is A laser light source having a wavelength of 780 nm is disposed at a position closer to the objective lens 29 than the semiconductor laser having a wavelength of 635 to 650 nm. For example, if the optical path distances at the air lengths of the semiconductor lasers with wavelengths of 635 to 650 nm and 780 nm and the objective lens 29 are L1 and L2, respectively, a semiconductor laser with a wavelength of 780 nm is mounted in the range of 0.55 ≦ L2 / L1 ≦ 0.75. The arrangement of the optical unit 23 is set.
[0042]
By disposing the semiconductor laser in such a range, the amount of aberration generated in the laser beam 22 and the laser beam 24 when the objective lens 29 is incident can be reduced to an allowable limit value or less. This is a preferable configuration because good optical characteristics can be obtained and good recording / reproducing characteristics can be realized for both the high-density disk 1a and the low-density disk 1b.
[0043]
Here, although not shown, the diffraction grating of the optical unit 21 is divided into three regions, and the diffraction grating of the optical unit 23 is formed of two divided regions. Further, the optical unit 21 includes a photodetector having a structure in which a four-divided light receiving element is disposed in the center and light receiving elements are provided on both sides thereof, and the optical unit 23 is configured by a photodetector having a five-divided light receiving element. The direction of the semiconductor laser in the optical unit 21 is attached so that the long axis direction of the far field pattern of the laser light 22 is parallel to the radial direction of the high-density disk 1. Thereby, the crosstalk generated between adjacent pits can be efficiently prevented. The direction of the optical unit 23 is arranged so that the three beams are substantially orthogonal to the radial direction of the disk 1 when the three-beam method is used as a tracking method.
[0044]
Which of the two semiconductor lasers existing in the optical system in the present embodiment emits light is switched depending on whether the disk 1 to be recorded / reproduced is the high-density disk 1a or the low-density disk 1b. That is, when the high-density disk 1 a is placed as the optical disk 1, the semiconductor laser provided in the optical unit 21 is operated to irradiate the laser beam 22, and the low-density disk 1 b is placed as the optical disk 1. In this case, the semiconductor laser provided in the optical unit 23 is operated and the laser beam 24 is irradiated.
[0045]
Next, playback operations on optical disks having different recording densities and substrate thicknesses, particularly operations when playing a DVD having a substrate thickness of 0.6 mm and a CD having a substrate thickness of 1.2 mm will be described.
[0046]
When reproducing the signal of the high-density disk 1 a having a thickness of 0.6 mm, the laser light 22 having a wavelength of 635 to 650 nm from the semiconductor laser provided in the optical unit 21 is transmitted through the diffraction grating and reflected by the beam splitter 25. Thereafter, the light passes through the wavelength filter 26, the collimator lens 27, and the rising mirror 28 and enters the objective lens 29. The laser beam 22 incident on the objective lens 29 is imaged on the recording surface of the high-density disk 1a (positioned approximately 0.6 mm from the substrate surface) by the focusing action of the objective lens 29. The reflected light from the high-density disk 1a passes through the objective lens 29, the rising mirror 28, the collimator lens 27, and the wavelength filter 26 again, is reflected by the beam splitter 25, and then enters the diffraction grating. The light incident on the diffraction grating is diffracted by the three divided regions of the diffraction grating and reaches the photodetector. In the above operation, the RF signal is detected from the sum obtained by converting the current output detected by the six-divided light receiving element into a voltage signal, and the focus error signal uses the first-order diffracted light from the semicircular region of the diffraction grating. Detect by hologram Foucault method. The tracking error signal is obtained by converting the voltage output of the first-order diffracted light in each of the two divided regions of the diffraction grating into a digital waveform by a comparator, and converting a pulse corresponding to the phase difference into an analog waveform through an integration circuit. To detect.
[0047]
When reproducing the signal of the low-density disk 1b, particularly when the tracking error signal is performed by the three-beam method, the laser beam 24 having a wavelength of about 780 nm from the semiconductor laser provided in the optical unit 23 is a diffraction grating (not shown). 3), the light beam is transmitted through the diffraction grating, transmitted through the beam splitter 25, and transmitted through the substantially circular portion at the center of the wavelength filter 26, and then to the collimator lens 27, the rising mirror 28, and the objective lens 29. Incident light is focused on the recording surface (positioned approximately 1.2 mm from the substrate surface) of the low-density disk 1b by the focusing action of the objective lens 29.
[0048]
The reflected light from the low-density disk 1b passes through the objective lens 29, the rising mirror 28, the collimator lens 27, the substantially circular portion at the center of the wavelength filter 26, and the beam splitter 25, and enters the diffraction grating. The light incident on the diffraction grating is diffracted and reaches a photodetector to detect a signal. The RF signal is detected from the sum obtained by converting the current output detected by the five-divided light receiving element into a voltage signal, and the focus error signal is detected by using a first-order diffracted light from a half region of the diffraction grating or by a holographic Foucault method. . The tracking error signal is detected by the three beam method.
[0049]
The above is the method used in the present embodiment. However, the method is not limited to this, and a known method can be used for any of the RF signal, the focus error signal, and the tracking error signal.
[0050]
Further, in the present embodiment, the case where two semiconductor lasers are used has been described. For example, a case where a plurality of three or more different types of discs such as a high density disc, a medium density disc, and a low density disc are reproduced. The case where three or more are arranged is also conceivable. In that case, an optical unit may be formed for each semiconductor laser, or a plurality of semiconductor lasers may be allocated to two optical units. In this case, the wavelength filter 26 preferably further has second and third selective transmission regions corresponding to the wavelengths of the respective semiconductor lasers in addition to the transmission region and the selective transmission region.
[0051]
In this embodiment, the wavelength of the semiconductor laser to be used is 635 to 650 nm and 780 nm in consideration of DVD and CD, but may be 400 to 430 nm and 635 to 650 nm, for example, and 780 nm. 635 to 650 nm and 400 to 430 nm, and may be increased as necessary.
[0052]
Further, the arrangement of the optical unit 21 and the optical unit 23 may be exchanged under a condition satisfying the range of 0.55 ≦ L2 / L1 ≦ 0.75. Further, instead of the beam splitter 25, a deflecting beam splitter that reflects the s-deflection component of the laser beam 22 with a wavelength of 635 to 650 nm and transmits the p-deflection component of the laser beam 24 with a wavelength of 780 nm may be used. Further, the laser light wavelength of the optical unit 21 may be changed to a short wavelength laser light corresponding to recording / reproducing of a high-density disk.
[0053]
Next, a volume for adjusting the amount of light emitted from the semiconductor laser according to one embodiment of the present invention will be described.
[0054]
Reference numeral 30 denotes a volume. The volume 30 is for adjusting the laser light amount of the semiconductor laser in the optical unit 21 and is provided on the side surface 41a of the carriage 41. The volume 30 is a resistance by rotating a + or-screw or a knob. It is often formed of something like a variable resistor that changes the value. Among the plurality of terminals 21a provided for power supply and signal extraction provided at the bottom of the optical unit 21, those related to the control of the semiconductor laser, the circuit board 21b and the flexible printed board 53 (hereinafter referred to as FPC53). Are electrically connected to each other.
[0055]
Reference numeral 31 denotes a volume. The volume 31 adjusts the laser light amount of the semiconductor laser in the optical unit 23, and is provided on the side surface 41a of the carriage 41 so as to be adjacent to the volume 30 described above. In many cases, it is formed of a variable resistor that changes a resistance value by rotating a screw or a knob. Among the plurality of terminals 23a provided for power supply and signal extraction provided at the bottom of the optical unit 23, those related to the control of the semiconductor laser, the circuit board 23b and the flexible printed board 53 (hereinafter referred to as FPC 53). Are abbreviated).
[0056]
Thus, by providing one volume for one semiconductor laser, the output adjustment of each semiconductor laser can be reliably performed with almost no error as compared with the case where they are also used. Further, by providing the volume 30 and the volume 31 close to each other, the operation distance of the volume jig can be shortened in the output adjustment work of the semiconductor laser, so that the working time can be shortened. As for the adjusting equipment for operating the volume adjusting jig, a small equipment with a small operating distance is improved. Therefore, productivity can be improved, the equipment configuration can be simplified, and the production cost can be reduced.
[0057]
In particular, it is preferable to set the distance between the volume 30 and the volume 31 close to each other within 10 mm because the jig operating distance can be further shortened and the adjustment equipment can be further downsized.
[0058]
In particular, since the volume 30 and the volume 31 are provided on the side of the carriage 41, for example, compared to the case where the volume is provided on the surface of the carriage 41 close to the recording medium or on the opposite surface, the protrusions of the volume are Since it does not exist in the thickness direction, it contributes to thinning of the entire optical pickup, and it becomes easy to realize a thin drive device that is a market need.
[0059]
Furthermore, by providing it in parallel with the longitudinal direction of the side surface portion 41a of the carriage 41 (the carriage movement direction), the operation distance of the volume jig can be shortened in the semiconductor laser output adjustment work. The time can be shortened, and the adjustment equipment for operating the volume adjustment jig can be a small equipment with a small operating distance. Therefore, it is possible to improve the productivity, simplify the equipment configuration and reduce the production cost, and the effect of reducing the production cost is particularly noticeable and contributes to the thinning of the entire optical pickup. The effect of facilitating realization of a thin drive device can also be obtained.
[0060]
In addition, as shown in the present embodiment, the volume 30 and the volume 31 are carriage side portions that are closer to the optical unit 21 than the optical axis of the laser light 24 emitted from the optical unit 23, and are as much as possible. 21 and the optical unit 23 are preferably provided at a short distance.
[0061]
By disposing the volume 30 and the volume 31 on the side surface satisfying such conditions, the distance between each optical unit and each volume can be shortened, so the size of the FPC 53 connecting between them can be reduced. In particular, since the area exposed on the surface of the carriage 41 facing the optical disk 1 or the back surface thereof can be reduced, the breakage of the FPC that may occur in the carriage 41 due to the operation is broken. The possibility can be greatly reduced.
[0062]
Furthermore, it is preferable that the volume 30 and the volume 31 are disposed on the same surface that is different from both the surface on which the optical unit 21 is disposed and the surface on which the optical unit 23 is disposed.
[0063]
With this arrangement, the output of the semiconductor laser can be adjusted while adjusting the rotation direction of the optical unit (adjusting the polarization plane of the laser light emitted from the optical unit in a predetermined direction). It can be carried out. That is, since two operations can be performed simultaneously at the same time, the operation time required for assembling the optical pickup can be shortened, and the manufacturing cost can be reduced.
[0064]
Next, the electrical connection between the volume 30 and the volume 31 and the semiconductor laser will be described with reference to the drawings. FIG. 9 is a diagram showing the configuration of the FPC in one embodiment of the present invention. FIG. 10 is a diagram showing the relationship between the FPC and the carriage in one embodiment of the present invention.
[0065]
Of the plurality of terminals 21a provided at the bottom of the optical unit 21, as the terminals related to the control of the semiconductor laser, at least a terminal for supplying power to the semiconductor laser and a light receiving section for monitoring light emitted from the semiconductor laser And a terminal for taking out a signal from the terminal. Electrical connection between the terminals 21a and the circuit board 21b is performed by joining the contact points between the terminals 21a and the printed electrodes formed on the circuit board 21b with solder, conductive epoxy or the like.
[0066]
The contact described above may be formed by an electrode formed around a through hole provided in the circuit board 21b and a terminal 21a penetrating the through hole, or an electrode printed on the circuit board 21b. And the end of the terminal 21a.
[0067]
And the electrode provided in the circuit board 21b and the electrode 53a provided in the FPC 53 are joined. The electrode provided on the circuit board 21b may be used for connection to the terminal 21a, or may be formed at another position and electrically connected to the terminal 21a. good. In the present embodiment, the electrode 53a of the FPC 53, the terminal 21a, and the electrode formed on the circuit board 21b are simultaneously soldered at the same position.
[0068]
Further, the electrode 53b of the FPC 53 and the electrode portion of the volume 30 are joined by solder or conductive epoxy, so that the semiconductor laser and the light receiving portion for monitoring and the volume 30 can be electrically connected.
[0069]
Of the plurality of terminals 23a provided at the bottom of the optical unit 23, the terminal for controlling the semiconductor laser includes at least a terminal for supplying power to the semiconductor laser and a light receiving for monitoring light emitted from the semiconductor laser. And a terminal for taking out a signal from the unit. The electrical connection between the terminals 23a and the circuit board 23b is performed by joining the contact points between the terminals 23a and the printed electrodes formed on the circuit board 23b with solder or conductive epoxy. The contact described above is formed by an electrode formed around a through hole provided in the circuit board 23b and a terminal 23a penetrating the through hole, or printed on the circuit board 23b. It may be formed by the electrode and the end of the terminal 23a.
[0070]
And the electrode provided in the circuit board 23b and the electrode 53c provided in the FPC 53 are joined. The electrode provided on the circuit board 23b may be used for connection to the terminal 23a, or may be formed at a different position and electrically connected to the terminal 23a. good. In the present embodiment, the electrode 53c of the FPC 53, the terminal 23a, and the electrode formed on the circuit board 23b are simultaneously soldered at the same position.
[0071]
Further, the electrode 53d of the FPC 53 and the electrode portion of the volume 31 are joined by solder or conductive epoxy, so that the semiconductor laser and the light receiving portion for monitoring and the volume 31 can be electrically connected.
[0072]
As described above, since a plurality of semiconductor lasers and a volume corresponding to each of them are configured by one FPC, the occurrence of bending or bending of the FPC due to the operation of the carriage is generated as compared with the case of configuring by a plurality of elongated FPCs. Therefore, it is possible to provide a highly reliable optical pickup with less occurrence of malfunction such as disconnection or entrainment.
[0073]
Further, since the FPC 53 is arranged so as to cover the carriage 41 on which the optical members are arranged, it also has a function of suppressing entry of dust, dirt, etc. into the carriage. Therefore, it is possible to provide an optical pickup in which dust or the like is hardly attached to each optical member and optical characteristics are hardly deteriorated.
[0074]
Reference numeral 32 denotes a superimposing circuit for superposing the semiconductor laser in the optical unit 21, and an electrode 53 e of the FPC 53 is connected from the terminal 21 a through the volume 30.
[0075]
It is also possible to provide a circuit for superposing a high frequency on the semiconductor laser of the optical unit 23 as necessary.
[0076]
On the contrary, the volume 30 and the volume 31 are used for adjusting the laser light amount of the semiconductor laser in the optical unit 23 on the volume 30 side, and adjusting the laser light amount of the semiconductor laser in the optical unit 21 on the volume 31 side. It may be a volume. When three or more semiconductor lasers are provided, it is preferable to provide the same number of volumes as the number of semiconductor lasers.
[0077]
In this embodiment, the case where a plurality of optical units and volumes are connected by one FPC has been described. However, a predetermined effect can be obtained even when a plurality of FPCs are used, and lead can be used instead of FPC. A line may be used.
[0078]
Next, an actuator for driving the objective lens 29 will be described.
Reference numeral 33 denotes an objective lens holding cylinder, and the objective lens 29 is fixed to the objective lens holding cylinder 33 by means such as adhesion. The objective lens holding cylinder 33 is elastically held by a wire 39 described later, and is movable within a predetermined range.
[0079]
Reference numeral 34 denotes a permanent magnet magnetized to the north pole on the objective lens 29 side, and reference numeral 35 denotes a yoke of the permanent magnet 34. The permanent magnet 34 and the yoke 35 are fixed and are not movable like the objective lens holding cylinder 33.
[0080]
Reference numeral 36 denotes a focus coil for driving the objective lens holding cylinder 33 in the focus direction, and reference numeral 37 denotes a tracking coil for driving the objective lens 29 in the tracking direction. Each of the coils 36 and 37 is fixed to the objective lens holding cylinder 33 by means such as adhesion. The permanent magnet 34, the focus coil 36 and the tracking coil 37 can always follow the focus direction and the tracking direction with respect to the disk 1 in the magnitude and direction of the current flowing through the permanent magnet 34 and the tracking coil 37.
[0081]
Reference numeral 38 denotes a relay substrate that supplies power to the focus coil 36 and the tracking coil 37, and the relay substrate 38 is attached to both side surfaces of the objective lens holding cylinder 33. The relay substrate 38 is also used to hold the objective lens holding cylinder 33 in the neutral position with the wire 39. One end of the wire 39 is fixed to the relay board 38 by means such as soldering, and the other end is fixed to the flexible board fixed to one end of the suspension holder 40 by means such as bonding by means such as soldering.
[0082]
The carriage 41 includes a screw shaft 42 on the optical unit 23 side with respect to the objective lens 29 and a guide shaft 43 on the opposite side so that the carriage 41 can move on the screw shaft 42 and the guide shaft 43 from the inner periphery to the outer periphery of the disk 1. It has become. At this time, the screw shaft 42 and the guide shaft 43 are arranged substantially parallel to each other. Further, a suspension holder 40, a permanent magnet 34, and a yoke 35 are fixed to the carriage 41. Since the objective lens holding cylinder 33 is attached to the suspension holder 40 via the wire 39 as described above, the objective lens holding cylinder 33 is held movably with respect to the carriage 40 by the elasticity of the wire 39.
[0083]
Furthermore, a guide portion 41 c formed integrally with the carriage 41 is engaged with the screw shaft 42, and a guide portion 41 d provided on the carriage 41 is also engaged with the guide shaft 43. By providing these guide portions 41 c and 41 d, the carriage 41 moves smoothly in the radial direction of the disk 1. Furthermore, a spiral groove is formed in the screw shaft 42, and a rack 52 having a protrusion that fits into the groove is attached to the carriage 40 via elasticity. Accordingly, when the rack 52 is guided by the spiral groove of the screw shaft 42 by the rotation of the screw shaft 42, a driving force is generated in the carriage 41 along the axial direction of the screw shaft 42, and the carriage is driven by the driving force. 41 moves along the axial direction of the screw shaft 42.
[0084]
In FIGS. 1 and 6, the flexible substrate 7 for supplying power to the optical units 21 and 23, the superimposing circuit 32, the focus coil 36, and the tracking coil 37 is drawn between the carriage 41 and the protective cover 44 and the disk. 1 is taken out from the carriage 41 in the outer circumferential direction of the disk 1, is drawn around so as to have an arm bend on the disk 1 side, passes again between the carriage 41 and the protective cover 44, and is fixed by the fixing block 45 and the thrust spring 46. 5 has been put out. Here, a reinforcing plate is fixed to a portion of the flexible substrate 7 that is routed after the carriage 41 by a means such as adhesion to a portion that does not bend, adheres to the side surface of the carriage 41 of the protective cover, and hangs down to the carriage side. I am trying not to. Further, the reinforcing plate of the flexible substrate 7 is always overlapped without the tip of the reinforcing plate being detached from the carriage 41 even when the optical pickup 3 is moved to the outermost diameter position of the disk 1.
[0085]
Next, the feed unit 4 will be described.
Reference numeral 47 denotes a feed motor with motor shafts protruding at both ends. A motor gear 48 is attached to one end, and an encoder 49 having a slit in the circumferential direction is attached to the other end by means such as thick insertion. A train gear 50 is used to decelerate the rotation of the feed motor 47. A screw shaft gear 51 is also used to decelerate the rotation speed of the feed motor 47 and is fixed to the screw shaft 42 by means such as thick insertion to transmit the rotation.
[0086]
【The invention's effect】
  As described above, according to the present invention, the volume for adjusting the amount of semiconductor laser light can be arranged on a surface different from the surface on which the plurality of optical units are arranged, and the interval between the adjustment volumes can be reduced. Miniaturization is possible. In addition, since the equipment with the function to adjust each adjustment volume is close, the equipment configurationofSimplification is possible.Further, by arranging the first adjusting means and the second adjusting means on the side surface of the carriage that is located on the second light source side with respect to the optical axis of the first outgoing light, the first light source is Since the distance connecting the optical unit provided, the optical unit provided with the second light source, the first adjusting means, and the second adjusting means can be shortened, the area of the connection cable connecting them can be reduced. can do. As a result, since the area of the connection cable exposed on the surface of the carriage facing the optical disk or on the back surface thereof can be reduced, disconnection due to the bending of the connection cable that changes as the carriage moves can be prevented. Further, by arranging the first adjusting means and the second adjusting means on the same surface, the position of the jig used when adjusting the light amount of the first adjusting means and the light amount adjustment of the second adjusting means. Since the position of the jig used when performing the adjustment can be brought closer, the jig used when adjusting the light quantity of the first adjusting means and the jig used when adjusting the light quantity of the second adjusting means are combined. And the movement distance can be shortened. As a result, the first adjustment means and the second adjustment means can be adjusted with the same small equipment, and the time for moving the jig can be shortened, so that the productivity can be improved and the equipment configuration can be simplified. Cost can be reduced. Furthermore, by adjusting the light amount of the first light source with the first adjusting means and adjusting the light amount of the second light source with the second adjusting means, the light amount adjustment of each light source can be adjusted independently, The amount of light in the first light source and the second light source can be reliably adjusted with almost no error.
[Brief description of the drawings]
FIG. 1 is a front view of an optical pickup according to an embodiment of the present invention.
FIG. 2 is a front view of a spindle motor unit according to an embodiment of the present invention.
3 is a cross-sectional view taken along line AA in FIG. 2 according to an embodiment of the present invention.
FIG. 4 is a front view of an optical pickup according to an embodiment of the present invention.
5 is a BB cross-sectional view of FIG. 4 in an embodiment of the present invention.
6 is a cross-sectional view of CC in FIG. 4 in one embodiment of the present invention.
FIG. 7 is a front view of a conventional optical pickup unit.
8 is a DD cross-sectional view of the conventional optical pickup unit in FIG.
FIG. 9 is a diagram showing a configuration of an FPC according to an embodiment of the present invention.
FIG. 10 is a diagram illustrating a relationship between an FPC and a carriage according to an embodiment of the present invention.
[Explanation of symbols]
1 Optical disc
1a high density disc
1b Low density disc
2 Spindle motor section
3 Optical pickup section
4 Feed section
21 Optical unit
21a terminal
21b Circuit board
22 Laser light
23 Optical unit
23a terminal
23b circuit board
24 Laser light
30, 31 volumes
41 Carriage
41a Side surface
53 FPC
53a, 53b, 53c, 53d Electrode

Claims (8)

A first light source; an optical member that transmits the first emitted light emitted from the first light source; an objective lens that converges the first emitted light transmitted through the optical member; and the first output. A second light source that enters the optical member from a direction perpendicular to the incident light and emits light guided on the same optical path as the first emitted light, and the first light source and the second light source are mounted. a carriage for a first adjustment means adjusts the amount of light of the first light source, and a second adjusting means adjusts the amount of light of the second light source, the first adjusting means and the second The adjusting means is disposed on a side surface of the carriage that is located on the second light source side with respect to the optical axis of the first emitted light . The surface located closer to the second light source than the optical axis of the first emitted light is at least one surface of the surface on which the first light source is disposed or the surface on which the second light source is disposed. The optical pickup according to claim 1, wherein the optical pickup is a surface adjacent to the surface . The surface on which the first adjustment unit and the second adjustment unit are disposed is different from both the surface on which the first light source is disposed and the surface on which the second light source is disposed. The optical pickup according to claim 1 . A pickup capable of reproducing a first recording medium and a second recording medium having different recording densities, a first light source that irradiates light to the first recording medium, and an irradiation from the first light source, A first optical unit including a first light receiving unit configured to receive light reflected by the first recording medium, the first light source, and the first light receiving unit; and the first light source. An optical member that transmits the first outgoing light emitted from the optical lens, an objective lens that converges the first outgoing light that has passed through the optical member, and the optical member from a direction perpendicular to the first outgoing light. A second light source that emits light and emits light guided on the same optical path as the first outgoing light, and receives light emitted from the second light source and reflected by the second recording medium A second light receiving means; the second light source; and the second light receiving means. A second optical unit comprising a carriage for mounting the first optical unit and the second optical unit, a first adjusting means adjusts the amount of light of the first light source, the second light source A second adjusting unit that adjusts the amount of light , and the first adjusting unit and the second adjusting unit are arranged on the side surface of the carriage from the optical axis of the first emitted light. An optical pickup which is disposed on a side surface . First connection means for electrically connecting the first terminal group provided in the first optical unit and the first adjustment means; and second terminals provided in the second optical unit A second connecting means for electrically connecting a group and the second adjusting means, wherein the first connecting means and the second connecting means are formed by one flexible printed circuit; The optical pickup according to claim 4. The surface located closer to the second light source than the optical axis of the first emitted light is either the surface on which the first light source is disposed or the surface on which the second light source is disposed. 6. The optical pickup according to claim 4, wherein the optical pickup is a surface adjacent to the surface . The surface on which the first adjustment unit and the second adjustment unit are disposed is different from both the surface on which the first light source is disposed and the surface on which the second light source is disposed. The optical pickup according to claim 4 or 5, wherein: 8. The optical pickup according to claim 1, wherein a distance between the first adjusting unit and the second adjusting unit is set to 10 mm or less.

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