JP2000207797A - Pickup device and its manufacture as well as magnetooptical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily ensure the light path of a laser beam, and at the same time to radiate heat to be generated by a magnetic filed generation coil. SOLUTION: A magnetooptical head part 25 is equipped with lenses 41 and 42 for focusing light from a light source to a magnetooptical recording layer 2a of a magnetooptical disk 2 and a coil support substrate 44, a coil part 46 that is arranged on an opposite surface that opposes the magnetooptical disk 2 on the coil support substrate 44 mounted onto a surface opposite to the magnetooptical disk 2 of the lens 41 and generates a magnetic filed by supplying current, and a wiring member 51 that is apart from the coil part 46 by specific distance for mounting to the coil support substrate 44, does not interfere with the light path of light L by an end part at a light-axis side, and is used as a cooling member being positioned inside the outer-periphery end of the coil support substrate 44.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup device used in a magneto-optical disk device for recording or reproducing an information signal on or from a magneto-optical recording medium such as a disk, a method of manufacturing the optical pickup device, and a disk. Related to the device.

[0002]

2. Description of the Related Art In recent years, with the development of technology for digitally recording video data such as moving images and still images, a large amount of data has been handled, and a conventionally used floppy disk or the like has been used. Instead of a magnetic disk,
Magneto-optical disks using magneto-optical recording, which have a higher recording density, are becoming widespread.

In such a device for recording data on a magneto-optical disk, power saving and reduction in size and weight have been promoted with the recent spread of portable personal computers and the like.

When recording data on a magneto-optical disk, a laser beam is applied to a position on the disk where data is to be recorded, and the temperature of the magnetic material (magneto-optical recording layer) at that position is raised to the Curie temperature. The coercive force corresponding to the data recorded at that position is eliminated, and a magnetic field corresponding to the data to be newly recorded is applied to the position (the position where the temperature is the Curie temperature) to obtain the data. Record

As described above, the magnetic field generating coil (magnetic head) for applying a magnetic field at the time of data recording is arranged on the opposite side of the optical pickup device that irradiates laser light with the disk interposed therebetween. Then, the magnetic field generating coil and the optical pickup device respectively move to a position where data is recorded, apply a magnetic field to a predetermined position, and irradiate a laser beam.

[0006]

By the way, the near-field optical recording technique (the distance between the recording medium and the optical lens is set to an optical contact state, the numerical aperture NA is set to 1 or more,
The recording layer is formed on the optical lens side of the substrate of the optical recording medium as a means for securing an optical skew margin and a substrate thickness margin as the numerical aperture NA increases as well as the technique for increasing the recording density. There is a way to do that. When the position of the recording layer on the magneto-optical disk is on the optical lens side, when the magneto-optical disk is used, the magnetic field generating coil must be arranged on the same side.

In the case where the optical lens and the magnetic field generating coil are arranged on the same side, the optical path of the light condensed by the optical lens must not interfere with the magnetic field generating coil. Since an opening for emitting laser light is provided at the center, a core material made of a magnetic material cannot be arranged on the entire surface.
Providing the center hole in the magnetic field generating coil in order to secure the optical path of the laser light in this way is disadvantageous for concentrating the generated magnetic field, and increases the current applied to the magnetic field generating coil.

Further, when the numerical aperture NA of the optical lens increases, the diameter of the center hole of the magnetic field generating coil must be increased. Therefore, the electric resistance value of the magnetic field generating coil increases, and the amount of heat generated from the magnetic field generating coil decreases. The problem that the number increases. For example, when the temperature rises due to the generated heat, the magnetic field generating coil formed on the optical lens may be peeled off.

As a substrate material for forming the magnetic field generating coil, there is a substrate material such as an optically transparent glass material.
For example, there is a case where a magnetic field generating coil is formed on the surface of the focusing lens facing the magneto-optical disk.

As described above, when the magnetic field generating coil is formed on the glass material, the optical path can be provided in the substrate material on which the magnetic field generating coil is formed. Can be narrowed to the vicinity of the optical path, but glass materials and the like generally have a drawback that heat dissipation is poor because of low thermal conductivity. That is, the glass material is not suitable for dissipating heat generated from the magnetic field generating coil.

In view of the above, it is conceivable to provide a magnetic field generating coil on a substrate material having excellent heat conduction properties. However, a hole is formed in an optically opaque material at a portion serving as an optical path, and the alignment is performed. Since errors must be included in the calculation, compared to forming a magnetic field generating coil on a substrate material such as an optically transparent glass material, the inner diameter of the coil must be increased, A problem arises in that the amount of current supplied to the coil is required.

The present invention has been made in view of the above circumstances, and an optical pickup device capable of radiating heat generated from a magnetic field generating coil while easily securing an optical path of laser light. It is another object of the present invention to provide a method of manufacturing an optical pickup device and a magneto-optical disk device.

[0013]

In order to solve the above-mentioned problems, an optical pickup device according to the present invention has a lens for converging light from a light source to a magneto-optical recording layer of an optical recording medium, and an optical recording device for the lens. A magnetic field generating element that is arranged on the facing surface facing the medium and receives a current to generate a magnetic field; and a lens that is attached to the lens at a predetermined distance from the magnetic field generating element and has an optical axis side end. A cooling unit that does not hinder the optical path and is located inside the outer peripheral end of the lens.

In the optical pickup device having such a configuration, the cooling member is attached to the lens at a short distance from the magnetic field generating element without obstructing the optical path. Thereby, the heat generated by the magnetic field generating element
The light is transmitted to the cooling member via the lens.

Further, in order to solve the above-mentioned problems, a method for manufacturing an optical pickup device according to the present invention includes a method for manufacturing a magnetic field generating element provided on an optical member provided with a magnetic field generating element. A step of attaching cooling means for attaching the cooling means such that the end portion on the optical axis side does not obstruct the optical path and is located inside the outer peripheral end of the lens; Is attached to a lens member on which light from a light source is incident, and a supporting substrate is attached to form a lens.

In such a method of manufacturing the optical pickup device, the cooling member is attached to the lens at a short distance from the magnetic field generating element without obstructing the optical path.

Further, in order to solve the above-mentioned problems, a magneto-optical disk drive according to the present invention has a lens for converging light from a light source on a magneto-optical recording layer of an optical recording medium, and a lens for the optical recording medium. It is arranged on the facing surface that is opposed,
A magnetic field generating element that generates a magnetic field when a current is supplied, and is attached to the lens at a predetermined distance from the magnetic field generating element, so that the optical axis side end does not obstruct the optical path and is higher than the outer peripheral end of the lens. And an optical element having a cooling means located inside.

In the magneto-optical disk drive having such a configuration, the cooling member is attached to the lens at a short distance from the magnetic field generating element without obstructing the optical path. Thereby, the heat generated by the magnetic field generating element is transmitted to the cooling member via the lens.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. The present embodiment is applied to a recording and / or reproducing apparatus (hereinafter, referred to as a magneto-optical disk device) for recording and / or reproducing data on a magneto-optical disk as an optical recording medium.

This magneto-optical disk device has a magneto-optical head 25 having a configuration as shown in FIG. The magneto-optical disk device 1 shown in FIG. 2 records and reproduces information signals on and from the magneto-optical disk 2 using the magneto-optical head unit 25.

As shown in FIG. 1, the magneto-optical head unit 25 irradiates the light from the light source with the magneto-optical recording layer 2 of the magneto-optical disk 2.
a and the coil support substrate 41 for converging to a, and a coil support substrate 44 attached to the surface of the lens 41 facing the magneto-optical disk 2 on the surface facing the magneto-optical disk 2 The coil unit 4 is a magnetic field generating element that is supplied with a current to generate a magnetic field.
6 and a predetermined distance from the coil portion 46, and is attached to the coil support substrate 44 so that the optical axis side end does not obstruct the optical path of the light L and is located inside the outer peripheral end of the coil support substrate 44. And a wiring member 51 which is a cooling member to be positioned.

The magneto-optical disk drive 1 achieves a high NA with the magneto-optical head 25 having the above-described configuration, and efficiently applies a magnetic field to the magneto-optical recording layer 2a of the magneto-optical disk 2 with low power consumption. It can be applied, and the heat generated from the coil portion 46 can be radiated by the wiring member 51.

FIG. 2 shows a specific example of the magneto-optical disk drive 1. The magneto-optical disk drive 1 includes a spindle motor 3 for driving the magneto-optical disk 2 to rotate, and a magneto-optical disk 2 rotationally driven by the spindle motor 3.
And a head 4 for recording a predetermined signal to the optical disk 2 and reading a signal recorded on the magneto-optical disk 2 to output a light receiving signal for generating an MO reproduction signal and a control signal.
A control signal generator 5 for receiving a light receiving signal output from the head 4 to generate a control signal; and controlling the head 4 in the radial direction of the magneto-optical disk 2 based on the control signal supplied from the control signal generator 5. Or a drive actuator 6 for moving the optical disc 2 in the direction of coming and going.

The spindle motor 3 is connected to a power supply (not shown). When a driving current is supplied from the power supply, the spindle motor 3 rotates the held magneto-optical disk 2 at a predetermined speed.

When a recording signal is supplied from a predetermined device (not shown), the head 4 irradiates the light to the magneto-optical recording layer 2a of the magneto-optical disk 2 and generates a magnetic field corresponding to the recording signal to generate a light. A predetermined signal is recorded on the portion of the magnetic recording layer 2a where the light is irradiated. The head 4 irradiates the magneto-optical recording layer 2a of the magneto-optical disk 2 with light, detects the return light, reads data recorded on the magneto-optical disk 2 and outputs the data as an MO reproduction signal. Then, the light receiving signal is supplied to the control signal generator 5.

The control signal generator 5 includes a focus matrix circuit 8, a tracking matrix circuit 11,
Phase compensation circuits 9 and 12 and amplifiers 7, 10 and 13 are provided.

The focus matrix circuit 8 generates a focus error signal based on the light receiving signal supplied from the head 4 via the amplifier 7, and supplies the focus error signal to the phase compensation circuit 9.

The phase compensating circuit 9 performs phase compensation of the focus error signal supplied from the focus matrix circuit 8, and supplies the phase-compensated signal to the driving actuator 6 via the amplifier 10.

The tracking matrix circuit 11 generates a tracking error signal based on the light receiving signal supplied from the head 4 via the amplifier 7, and supplies the tracking error signal to the phase compensation circuit 12.

The phase compensation circuit 12 compensates for the phase of the tracking error signal supplied from the tracking matrix circuit 11 and supplies the phase-compensated signal to the driving actuator 6 via the amplifier 13.

The drive actuator 6 moves the head 4 in the direction of coming into contact with and separating from the magneto-optical disk 2 based on a focus error signal supplied from the focus matrix circuit 8 via the phase compensation circuit 9 and the amplifier 10.
Performs focusing control. Further, the driving actuator 6 moves the head 4 in the radial direction of the magneto-optical disk 2 based on the tracking error signal supplied from the tracking matrix circuit 11 via the phase compensation circuit 12 and the amplifier 13 to perform tracking control. Do.

Here, the details of the head 4 will be described.

As shown in FIG. 3, the head 4 includes a semiconductor laser 21 for emitting a predetermined laser beam. The laser beam emitted from the semiconductor laser 21 is first made to enter the collimator lens 22. I have.

The collimator lens 22 is connected to the semiconductor laser 2
The laser light emitted from 1 is arranged into parallel rays.
The laser light transmitted through the collimator lens 22 is incident on the first beam splitter 24 via the shaping prism 23 in a state where the laser light is adjusted to parallel light.

The first beam splitter 24 transmits the laser beam from the shaping prism 23 toward an optical element (magneto-optical head) 25 having an objective lens composed of two lenses and a thin-film coil, and also transmits the laser beam. The light is reflected by the magneto-optical recording layer 2a of the magnetic disk 2 and
The laser beam (return light) passing through is reflected toward the second beam splitter 26.

In the magneto-optical head section 25, the objective lens converges the laser beam from the first beam splitter 24 and irradiates the magneto-optical recording layer 2a of the magneto-optical disk 2 with a thin film. Coil is amplifier 3
A magnetic field having an intensity corresponding to the recording signal supplied via the laser beam 6 is applied to the laser beam irradiation position of the magneto-optical recording layer 2a.

The magneto-optical head unit 25 is designed to make the laser beam (return light) reflected by the magneto-optical recording layer 2a of the magneto-optical disk 2 enter the first beam splitter 24. The return light that has entered the first beam splitter 24 is reflected by the first beam splitter 24 as described above, and enters the second beam splitter 26.

The second beam splitter 26 reflects the return light reflected by the first beam splitter 24 toward the first condensing lens 27 at a predetermined ratio, and controls the half-wave plate 30 The light is transmitted toward the second condensing lens 31 through the light source.

The first condenser lens 27 converts the return light of the parallel light beam reflected by the second beam splitter 26 into convergent light, and converts the converged light into a first light through a cylindrical lens 28 that gives astigmatism. To the photodetector 29.

The first photodetector 29 has four divided light receiving sections, converts return light incident on each of the light receiving sections into an electric signal (light receiving signal), and outputs the electric signal (light receiving signal). It is supplied to the amplifier 7.

The second condenser lens 31 converts the return light of the parallel light beam supplied from the second beam splitter 26 via the half-wave plate 30 into convergent light, and makes it incident on the third beam splitter 32. It has been made like that.

The third beam splitter 32 converts a part of the return light converged by the second condenser lens 31 into a second light.
And the other part of the return light is reflected toward the third photodetector 34.

The second photodetector 33 and the third photodetector 3
Numeral 4 converts the return light incident from the third beam splitter 32 into an electric signal corresponding to the light amount, and supplies the electric signal to the differential amplifier 35.

The differential amplifier 35 calculates a difference between the electric signal supplied from the second photodetector 33 and the electric signal supplied from the third photodetector 34, and uses the calculation result as an MO reproduction signal. Are supplied to a predetermined device (not shown).

With the above configuration, the magneto-optical disk device 1 can record a predetermined information signal on the magneto-optical disk 2 or read a predetermined information signal from the magneto-optical disk 2. It has been.

The magneto-optical disk device 1 is not limited to a magneto-optical disk, but can be applied to a phase-change optical disk utilizing a phase change, a read-only optical disk, and the like. When recording an information signal on a phase-change optical disc, the head 4 irradiates the recording layer of the phase-change optical disc with laser light, and the magneto-optical disc apparatus 1 uses the phase change of the recording layer to convert the information signal. When recording and reading an information signal from the phase-change optical disc, the head 4 irradiates the recording layer of the phase-change optical disc with laser light to obtain a reproduction signal from a difference in return light depending on the state of the recording layer.

When reading information signals from a read-only optical disk, the magneto-optical disk device 1
The head 4 irradiates the signal recording layer of the read-only optical disk with laser light, and detects the return light to obtain a reproduction signal.

Next, the magneto-optical head 25 of the head 4 which is a main part of the present invention will be described.

As shown in FIG. 1, the magneto-optical head unit 25 includes two lenses 41 and 42 disposed on the optical path of the laser beam transmitted through the first beam splitter 24. , 42 are configured as objective lenses that converge the laser light emitted from the semiconductor laser 21. In the following description, of the two lenses, the lens disposed on the magneto-optical disk 2 side is referred to as a front lens 41, and the other lens is referred to as a rear lens 42.

The front lens 41 and the rear lens 42 are each formed of a white plate glass, a blue plate glass, a quartz glass, or the like which is transparent to the transmitted light used in a predetermined shape.
Supported by the respective lens holders 43a and 43b,
It is arranged on the optical path of the laser beam transmitted through the first beam splitter 24. In particular, the front lens 41 is formed in a hemispherical shape, and is supported by the lens holders 43a and 43b such that a circular plane faces the magneto-optical disk 2. The spherical shape of the front lens 41 depends on the shape and arrangement of the rear lens 42 and the refractive index of the substrate thickness of the magneto-optical disk 2. Optimized so as not to be affected by aberration.

A front lens 41 and a rear lens 42
Are supported by the lens holders 43a and 43b,
The drive actuator 6 integrally moves the disk in the radial direction of the magneto-optical disk 2 and in the direction in which it comes into contact with and separates from the magneto-optical disk 2, so that tracking control and focusing control can be performed. When performing the focusing control, the front lens 41 or the rear lens 42 is moved in a direction in which the front lens 41 or the rear lens 42 comes into contact with or separates from the other lens, thereby correcting spherical aberration.

The magneto-optical head 25 has a front lens 41
Of the coil support substrate 44
Is provided.

The coil support substrate 44 is provided for the magneto-optical disk 2
A coil portion 46 is provided on a surface facing the light emitting device, and a central portion thereof is an emission surface 44d for emitting light. That is, a coil portion 46 having a center hole 46a is provided on the surface of the coil supporting substrate 44 facing the magneto-optical disk 2 so as to secure an optical path of light emitted from the emission surface 44d.

A projection 44e is formed on the back side of the coil support board 44, and a wiring member 51 is attached to a wiring member mounting surface 44f on the outer peripheral portion of the projection 44e. Here, the convex portion 44e has, for example, a substantially circular cross section in the radial direction of the optical axis of the laser beam L, and has a diameter such that an optical path of the laser beam L can be secured. The height of the convex portion 44e in the optical axis direction is
The thickness of the wiring member 51 in the optical axis direction is higher than that of the wiring member 51. That is, when the wiring member 51 is attached to the coil support substrate 44, a slight space is provided between the wiring member 51 and the front lens 41. The height is as high as possible.

The coil support substrate 44 is formed of, for example, the same material as the above-mentioned front lens 41,
That is, it is formed of a glass material such as white plate glass, blue plate glass, and quartz glass.

The wiring member 51 is formed in a substantially flat plate shape.
It is configured as a so-called double-sided substrate having conductive patterns 51a and 51b on the surface facing the magneto-optical disk 2 and the back surface. This wiring member 51 has an outer diameter of
It is formed larger than the outer diameters of the coil support substrate 44 and the front lens 41, and has a center hole 44h substantially at the center.
Are formed. In the wiring member 51, the above-described convex portion 44e having substantially the same diameter as the center hole 44h is located inside, and
It is attached to a coil support substrate 44.

When the conductive patterns 51a and 51b are attached to the lens supporting substrate, a part thereof is formed on the wiring member 51 so as to be located outside the outer peripheral ends of the coil supporting substrate 44 and the front lens 41. ing. That is, the conductive patterns 51 a and 51 b are configured such that the inner portion is in contact with the back surface of the coil support substrate 44 and the outer portion is located in the outer peripheral direction from the outer peripheral ends of the coil support substrate 44 and the front lens 41. . This conductive pattern 51a,
51b is used at least for supplying current to the coil unit 46, and the like. Also, the conductive patterns 51a, 51b
Is formed using a material having good heat conduction properties, for example, using Cu.

The conductive pattern 51a formed on the front surface facing the magneto-optical disk 2 and the conductive pattern 51b formed on the back surface are electrically connected to each other. Insertion hole 51 provided
c and are electrically connected. This wiring member 51
Supplies the above-described current to the coil portion 46. Specifically, the conductive pattern 51a is connected to the terminal 50 from the coil portion 46, whereby the conductive pattern 51b on the back surface is The supplied current is supplied to the coil unit 46 via the conductive pattern 51a on the surface. The connection of the terminal 50 to the conductive pattern 51a is made by, for example, a solder 52.

The supply of the current to the wiring member 51 is performed by a current supply wiring 53 extending from a current supply means (not shown) connected to the conductive pattern 51b on the back surface. Here, the connection of the power supply wiring 53 to the conductive pattern 51b is made by, for example, solder 54.

The coil supporting substrate 44 is attached to the front lens 41 so as to sandwich the wiring member 51 attached to the outer peripheral portion of the back surface. Specifically, the front lens 4 of the convex portion 44e of the coil support substrate 44
The incident surface 44g on which the laser light from the lens 1 is incident and the laser light emitting surface 41a of the front lens 41 are opposed to each other. A matching oil 55 having a refractive index of? The coil support substrate 44 and the front lens 41 are optically integrated by the matching oil 55.

The coil support substrate 44 and the front lens 41, which are thus optically integrated, are mounted on the lens holder 43a. Specifically, the wiring member 5
The back surface ₁ and the mounting surface 43a1 provided at the end of the lens holder 43a facing the magneto-optical disk 2 are adhered by an adhesive 56.

[0062] Then, the mounting surface 43a ₂ of the other end of the lens holder 43a is by being attached to the outer peripheral portion 42a of the facing surface of the magneto-optical disc 2 of the rear lens 42, the rear lens 42 and the front lens 41 An integrated objective lens is configured. Here, the mounting portion 43a ₂ of the lens holder 43a is by an adhesive 57, is attached to the rear lens 42. Then, a lens holder 43b is provided on an outer peripheral portion 42b of the rear surface where the laser beam of the rear
Are attached by an adhesive 58 or the like.

As shown in FIG. 4, the coil portion 46 is formed on the main surface of the coil support substrate 44 facing the magneto-optical disk 2 and around the emission surface 44d. And a spiral-shaped thin-film coil 48 formed on the magnetic core 47. here,
The magnetic core 47 is provided adjacent to the thin film coil 48 because the magnetic field efficiency of the coil portion 46 is improved.

The magnetic core 47 has a center hole 47a and is formed on a ring. The center hole 47a of the magnetic core 47 is provided to allow the laser light converged by the rear lens 42 and the front lens 41 to pass through and irradiate the magneto-optical recording layer 2a of the magneto-optical disk 2. . That is, the diameter of the center hole 47a allows the laser light converged by the rear lens 42 and the front lens 41 to pass,
It is determined as a requirement to irradiate the magneto-optical recording layer 2a of the magneto-optical disk 2, and is, for example, about 110 μm. The coil section 46 will be described later in detail.

The magneto-optical head 2 constructed as described above
Reference numeral 5 denotes a position at which data is recorded on the magneto-optical disk 2 which is irradiated with laser light converged by the rear lens 42 and the front lens 41 to record the temperature of the magnetic material at that position. To the Curie temperature, eliminate the coercive force corresponding to the data recorded at that position,
Further, a magnetic field corresponding to the data to be newly recorded can be applied to the position (the position where the temperature is the Curie temperature) to record the data.

The magneto-optical head unit 25 includes a wiring member 51 on the back surface of the coil supporting substrate 44 on which the coil unit 46 is formed.
Since a and 51 b are made of a member having high thermal conductivity, heat generated by applying an electric field to the coil portion 46 can be radiated through the wiring member 51. That is, in the magneto-optical head section 25, the wiring member 51 functions as a cooling member that supplies current to the coil section 46 and radiates heat generated in the coil section 46.

Here, it is conceivable to attach a wiring portion serving as a cooling member to the side surface of the coil support substrate 44. However, the wiring member 51 formed by applying the present invention is mounted on the back surface of the coil support member 44. With this arrangement, it is possible to dispose the wiring member 51 at a position close to the coil portion 46 even if the coil support substrate 44 is provided with the coil portion 46 forming portion on the opposing surface of the magneto-optical disk 2. Therefore, the heat radiation efficiency via the coil support substrate 44 is improved.

The wiring member 51 is formed of the coil supporting substrate 4.
Although it is conceivable to attach to the front lens 41, it is possible to efficiently dissipate heat because it is attached to (contacted with) the coil support substrate 44. It is possible.
For example, by attaching the wiring member 51 to the front lens 41,
When the lens support substrate 44 is attached to the front lens 41, there is a possibility that a gap is formed between the front lens 41 and the coil support substrate 44. This is because the efficiency of heat transfer to the heat exchanger is reduced.

Furthermore, since the conductive pattern 51a on the magneto-optical disk 2 side is connected to the conductive pattern 51b on the back surface, it is possible to radiate heat also in the direction of the back surface of the coil support substrate 44. And heat is efficiently dissipated. Further, the wiring member 51 is connected to the coil support substrate 44.
The heat radiation characteristics are further improved by forming the outer diameter larger than the outer diameter.

Further, when the wiring member 51 is a double-sided board,
Since the current supply wiring 53 is disposed on the back surface of the wiring member 51 and is located far from the magneto-optical disk 2, there is a danger that the current supply wiring 53 touches the magneto-optical disk 2. It decreases significantly. Moreover,
By providing the current supply wiring 53 on the back surface of the wiring member 51, when the current supply wiring 53 is electrically connected to the wiring member 51 by soldering, no problem occurs even if the connection portion such as solder swells. .

Further, by making the wiring member 51 larger than the outer diameter of the front lens 41, a space at the connection position on the back surface can be obtained, and the conductive pattern 5
A space for connection to 1b is obtained, and electrical connection is facilitated.

The coil unit 46 for generating a magnetic field as described above
Is provided on the surface opposing the magneto-optical disk 2, and the coil support substrate 44 provided with the wiring member 51 for supplying a current to the coil portion 46 on the back is provided.
5 can obtain the effect as described above.

Next, a method of manufacturing (assembling) the magneto-optical head 25 will be described. As shown in FIG. 5, the manufacturing process of the magneto-optical head unit 25 described here includes the manufacturing process of the coil support substrate 44 and the assembly of the coil support substrate 44, the wiring member 51, the front lens 41, and the rear lens 42. Process.

The manufacturing process of the coil support substrate 44 is performed according to the following procedure.

In step S1, the coil portion 46 is formed on the substrate (base material of the coil supporting member 44). The coil portion 46 is formed by patterning, film formation by a vacuum process, film plating, and the like, and is easily performed by a wafer process.

In step S2, a protruding portion (convex portion 44e) is formed on the back surface (on the side where the coil portion 46 is not formed) of the substrate on which the coil portion 46 is formed. That is, a depression for attaching the wiring member 51 is generated. The projection is formed by patterning, etching, or the like. Further, as means for etching, there are ion milling, powder beam etching and the like. For example, by using powder beam etching, it is possible to make the protrusion deep (thick). This step can also be easily formed by performing a wafer process.

Further, by processing the etching depth to be larger than the thickness of the wiring member 51, it is possible to prevent the number of steps from increasing. For example, as described above, by making the protrusion 44 e thicker than the thickness of the wiring member 51, after attaching the wiring member 51 to the coil support member 44, these protrusions 44 e are simply brought into contact with the front lens 41. A member can be attached, so that the surface processing of the front lens 41 for positioning is not required.

In step S3, the substrate on which the coil portions 46 and the protrusions 44e are formed as described above is divided to form the coil support substrate 44. As a forming means, there is a dicing step or the like, but it is also possible to use a means such as forming a coil portion 46 having a curved outer shape using powder beam edging.

With the above configuration, the coil supporting substrate 4
4 is produced. Then, the wiring member 51, the front lens 41, and the rear lens 42 are assembled on the coil supporting substrate 44 thus manufactured. This assembly process
The following procedure is performed.

In step S4, the wiring member 51 is attached to the coil support board 44. Specifically, the inner peripheral portion of the surface on which the conductive pattern 51 a of the wiring member 51 is formed is attached to the back surface 44 f of the coil support substrate 44 by the adhesive 5.
Adhere with 6.

In step S5, the wiring member 51 and the coil section 46 are electrically connected. Specifically, the terminal 50 of the coil portion 46 is connected to the conductive pattern 5 by the solder 52.
1a. The order of this step and the previous step (step S4) does not matter.

In step S 6, the member in which the wiring member 51 and the coil support substrate 44 are integrated is moved to the front lens 41.
Glue to Specifically, the back surface of the wiring member 51 to the mounting portion 43a ₁ of the lens holder 43a is bonded by an adhesive 56. At this time, alignment is also performed. In addition,
In this step, it is assumed that the front lens 41 and the lens holder 43a are bonded in advance.

Here, the convex portion 44e of the lens support substrate 44
The liquid 55 is filled between the light incident surface 44g and the light outgoing surface 41a of the front lens 41, so that the lens support substrate 44 and the front lens 41 are optically integrated. . By using the liquid 55 having the same refractive index as the lens support substrate 44 and the front lens 41, the lens support substrate 44 and the front lens 41 are in the same state as when they are optically integrated. In particular,
A matching oil can be used for the liquid 55. However, the present invention is not limited to this. For example, if a liquid having an adhesive property is used, the bonding process between the lens support substrate 44 and the front lens 41 can be easily performed. Become. Further, after the alignment step is completed, the liquid does not need to be a liquid, and a liquid that solidifies may be used.

The lens support substrate 44 and the front lens 4
By performing the optical connection with the liquid 1 by filling the liquid 55, the liquid 55 is also resistant to dust. For example, when dust enters the liquid 55, the dust will be present on the optical path. However, when the reflection of light due to dust when the liquid 55 is present and when the dust is not present is compared, As a result, the reflection of light due to dust is negligible, and the influence of dust can be reduced.

Further, by adjusting the thickness of the liquid portion, the thickness of the coil support substrate 44 and the error of the front lens 41 can be adjusted.

In step S7, the coil support substrate 4
4. A member in which the wiring member 51 and the front lens 41 are integrated is attached to the rear lens 42. Specifically, the mounting portion 43a ₂ of the lens holder 43a, the laser beam of the rear lens 42 is adhesively bonded 57 to the outer peripheral portion 42a of the surface to be emitted. At this time, the alignment is performed by adjusting the thickness of the adhesive 57.

In step S8, the wiring member 51 is electrically connected to the outside. That is, the current supply wiring 53 from the current supply means (not shown) is soldered to the conductive pattern 51 b on the back surface of the wiring member 51. Here, since the wiring member 51 functions as a buffer member, the risk of affecting the alignment accuracy of the optical member is reduced.

Steps S1 to S8 as described above
By the above-described process, the coil portion 46 is formed, and the coil support substrate 44 is manufactured. The coil support substrate 44, the wiring member 51, the front lens 41, and the rear lens 52 are assembled. The manufacturing process ends.

The following effects can be obtained by manufacturing the magneto-optical coil unit 25 through the above-described steps.

A liquid 55 is filled between the coil support substrate 44 on which the coil portion 46 is formed and the front lens 41 to assemble them, thereby assembling the coil support substrate 44 and the front lens 4.
1 can be treated optically uniformly. Also,
By using a matching oil as the liquid 55,
Paralleling can be performed with high accuracy just by pressing.

For example, when the liquid 55 is not filled, if parallelization is performed by pressing and bonding is performed in that state, Fresnel reflection is required unless the entire optical path is brought into optically uniform contact. The unevenness occurs in the laser light, and the intensity of the laser light becomes uneven. Therefore, the surface accuracy of the exit surface 41a and the entrance surface 44g at the contact surface between the front lens 41 and the coil support substrate 44 is significantly improved. Therefore, it is necessary to consider the danger of dust and the like entering.

Further, by disposing the wiring member 51 at the periphery of the protrusion 44 e on the coil support substrate 44, that is, at the recessed portion, the depth of the recess may be larger than the thickness of the wiring member 51. The accuracy of the recess forming process can be reduced. Further, since the management of the substrate thickness (t) of the coil support substrate 44 can be managed in a wafer state, the number of management steps is remarkably reduced as compared with the case where the individual coil support substrates 44 are managed.

The electrical connection between the wiring member 51 and the coil portion 46 is made after the coil supporting substrate 44 and the wiring member 41 are bonded (after the above-described steps (4) and (5)), that is, optically. Because it can be done before
For example, there is no concern about displacement or the like in an electrical connection step of electrically connecting the coil portion 46 and the wiring member 51.
For example, before performing optical alignment, the coil unit 46
By soldering the terminal 50 and the wiring member 51 to each other, optical displacement due to heat shock does not occur.

Further, before attaching the front lens 41 to the rear lens 42, the front lens 41 and the coil supporting substrate 44 are assembled into an integrated member.
The thickness error of the coil support substrate 44 and the front lens 41
By adjusting the thickness of the adhesive 57 in the step of bonding the lens holder 43a to the rear lens 42, it is possible to cancel the error (spherical aberration) obtained by adding the thickness error of the lens unit 43 to the rear lens 42. Therefore, the management becomes easier as compared with the case where the thickness is individually managed. Further, the liquid 55 is inserted between the coil support substrate 44 and the front lens 41, and the thickness thereof is adjusted.
The adjustment can be performed even when the thicknesses of the fourth lens and the first lens are largely shifted.

The current supply wiring 53 to the wiring member 51
Is performed on the back surface of the wiring member 51, so that dirt due to dust and the like generated in the electrical connection process is removed from the optical surface (the light exit surface 44 of the coil support substrate 44).
d) and adhesion on the coil portion 46 or the like can be prevented.

Also, since the portions requiring optical alignment, such as the coil portion 46, are not attached to the wiring member 51, the connection step of the current supply wiring 53 is replaced by the optical alignment step. Even after completion, there is little danger of optical misalignment. For example, even if a soldering process or the like is performed to cause residual stress due to heat shrinkage or the like, the residual stress mainly occurs in the wiring member 51. Therefore, the coil portion 46, the front lens 41, the rear lens 42, etc. The degree of influence on the optical components is small.

Also, the coil support substrate 44 on which the coil portion 46 is formed and the front lens 41 are separately molded and optically integrated, so that, for example, the coil portion 46 and the laser beam It is not necessary to perform two processes for forming the incident surface at the same time, and the processes can be performed individually, which facilitates manufacturing.

Next, the recording / reproducing operation of the magneto-optical disk device 1 having the above-described magneto-optical head 25 will be described.

When recording predetermined data on the magneto-optical disk 2, the magneto-optical disk drive 1 rotates the magneto-optical disk 2 on which the spindle motor 3 is mounted, and drives the semiconductor laser 21 from the semiconductor laser 21 of the head 4. Light is emitted.

The laser light emitted from the semiconductor laser 21 enters the magneto-optical head 25 via the collimator lens 22, the shaping lens 23, and the first beam splitter 24. The laser beam incident on the magneto-optical head 25 is converged by the rear lens 42 and the front lens 41 of the magneto-optical head 25, passes through the center hole of the coil 46, and The light is applied to the magneto-optical recording layer 2a.

By irradiating the magneto-optical recording layer 2a of the magneto-optical disk 2 with a laser beam in this way, the magneto-optical disk device 1 reduces the magnetic material at the location irradiated with the laser beam to a temperature higher than the Curie temperature or the compensation temperature. And the magnetization at that point disappears.

The magneto-optical disk device 1 outputs the recording signal modulated in accordance with the data to be recorded to the amplifier 36.
Is supplied to the magneto-optical head section 25 via the thin film coil 48, the thin-film coil 48 generates a magnetic field corresponding to the recording signal, and this magnetic field is applied to a portion of the magneto-optical recording layer 2a of the magneto-optical disk 2 where the laser light is irradiated. Is applied.

Thus, the magneto-optical disk drive 1
Records predetermined data (recording signal) on the magneto-optical disk 2. Then, during this recording operation, the heat generated by the thin film coil 48 is radiated by the wiring member 51 on the back surface of the coil support substrate 44. The magneto-optical disk drive 1 performs the focusing control and the tracking control at the time of recording as well as at the time of reproduction, which will be described later.

When reading the data recorded on the magneto-optical disk 2, the magneto-optical disk device 1 rotates the magneto-optical disk 2 on which the spindle motor 3 is mounted, as in the case of the recording operation. The laser light is emitted from the fourth semiconductor laser 21.

The laser light emitted from the semiconductor laser 21 enters the magneto-optical head 25 via the collimator lens 22, the shaping lens 23, and the first beam splitter 24. The rear lens 42 of the magneto-optical head 25
Then, the light is converged by the front lens 41 and passes through the center hole of the coil portion 46, and the magneto-optical recording layer 2a
Is irradiated. The return light reflected by the magneto-optical recording layer 2a is transmitted to the second beam splitter 26, the half-wave plate 30,
Second condenser lens 31 and third beam splitter 32
Through the second photodetector 33 and the third photodetector 34
And is detected. The polarization planes of the return light from the magneto-optical recording layer 2a are rotated in directions opposite to each other by the direction of magnetization (corresponding to the value of recorded data) of the magneto-optical recording layer 2a due to the Kerr effect. Then, the return light from the magneto-optical recording layer 2a is incident on the second photodetector 33 and the third photodetector 34 via the third beam splitter 32, so that the direction of the polarization plane is changed. A change in the rotation angle (Kerr rotation angle) seen between the direction of the polarization plane of the light applied to the magneto-optical recording layer 2a is converted into a change in the light intensity, and the change in the intensity is detected.

The second photodetector 33 and the third photodetector 3
4 outputs the electric signal corresponding to the intensity of the incident return light to the differential amplifier 35, and the differential amplifier 35 calculates the difference between the outputs of the second photodetector 33 and the third photodetector 34. Calculate and M
Output as an O reproduction signal.

A part of the return light reflected by the magneto-optical recording layer 2a is reflected by the second beam splitter 26, and the first condenser lens 27 and the cylindrical lens 2
The light enters the first photodetector 29 through 8.

The first photodetector 29 converts the incident return light into an electric signal, and supplies the electric signal to the focus matrix circuit 8 and the tracking matrix circuit 11 via the control signal generator 5 and the amplifier 7. I do.

The focus matrix circuit 8 and the tracking matrix circuit 11 generate a focus error signal and a tracking error signal based on the signals, and drive the focus error signal and the tracking error signal via the amplifiers 10 and 13 for driving. It is supplied to the actuator 6.

The driving actuator 6 moves the magneto-optical head unit 25 in the direction of coming into contact with or separating from the magneto-optical disk 2 or in the radial direction of the magneto-optical disk 2 in response to the focus error signal and the tracking error signal. Focusing control and tracking control are performed.

As described above, the magnetic head unit 25 used in the magneto-optical disk device 1 has the coil unit 46.
Since the wiring member 51 is provided on the back surface of the coil support substrate 44 provided with the wiring member 51 so as to function as a heat radiator, heat generated when the magnetic field of the coil portion 46 is generated can be radiated.

The coil section 46 has the following structure.

As shown in FIGS. 4 and 6, the coil portion 46 is formed on the main surface of the coil support substrate 44a facing the magneto-optical disk 2 and around the emission portion 44d. And a spiral-shaped thin-film coil 48 formed on the magnetic core 47.

The material of the magnetic core 47 is, for example, Ni
-Fe alloy, Co-based amorphous alloy, Fe-Al-Si alloy, Fe-C
A wide range of materials can be used, such as a laminate of an alloy and a Ni-Fe alloy, an Fe-Ta-N alloy, a Mn-Zn ferrite, and it is also possible to use a combination of two or more of them. If the magnetic core 47 is formed of a conductive material, the thin film coil 48 can be connected to one of the electrodes via the magnetic core 47. The thin film coil 48 can be formed by separately providing an extraction electrode. There is no need to connect to one electrode.

The coil supporting substrate 4 of the magnetic core 47
An adhesive layer such as a Cr film is formed on the main surface of the coil support substrate 44 to improve the adhesion to the coil support substrate 4, and the magnetic core 47 on the coil support substrate 44a is formed via the adhesive layer. You may.

The thin-film coil 48 generates a magnetic field corresponding to a recording signal supplied from a predetermined device, and applies the magnetic field to a position of the magneto-optical recording layer 2a of the magneto-optical disk 2 where the laser beam is irradiated. Thus, it is formed on the magnetic core 47 so as to form a spiral shape having a center hole.

The thin film coil 48 is made of, for example, Cu, Ag,
It is made of a material having conductivity such as one selected from Au, or an alloy containing at least one or more of them, and is formed in a spiral shape having a central hole on the magnetic core 47 by using a photolithography technique. After being grown to a predetermined thickness by plating, or after being formed into a predetermined thickness on the magnetic core 47, the conductive material is formed into a spiral shape having a center hole by using photolithography technology. It is formed by being etched.

The thin-film coil 48 is embedded in an insulating layer 49 made of an insulating material to protect the thin-film coil 48, and a driving current is applied to the thin-film coil 48 from the outer periphery of the spiral shape. The one electrode 50a for supplying is drawn out.

When the magnetic core 47 is formed using a conductive material, the thin film coil 48
The inner peripheral portion of the spiral shape is connected to the other electrode 50b via the magnetic core 47. Here, the electrodes 50a,
The end of 50b becomes the above-described terminal 50 connected to the wiring member 51.

As the material of the insulating layer 49 for protecting the thin-film coil 48, for example, a resist material, polyimide, acrylic resin, or the like is used. Then, the insulating layer 49
Also, a center hole is provided at the center according to the shape of the thin film coil 48, and the laser light converged by the rear lens 42 and the front lens 41 passes through the center hole.

The thin-film coil 48 is mounted on the magneto-optical disk 2
Is formed on the magnetic core 47 on the coil support substrate 44 so as to be substantially parallel to the magneto-optical recording layer 2a. Therefore, the direction of the current flowing through the thin-film coil 48 is substantially parallel to the magneto-optical recording layer 2a of the magneto-optical disk 2, so that the thin-film coil 48 passes through the center hole and A magnetic field substantially perpendicular to the layer 2a is generated, and this magnetic field is applied to the magneto-optical recording layer 2a.

A magnetic field is generated by such a coil portion 46, and the heat generated at that time is radiated by the wiring member 51.

[0123]

The optical pickup device according to the present invention has the following features.
A lens for converging light from a light source on the magneto-optical recording layer of the optical recording medium, a magnetic field generating element disposed on the surface of the lens facing the optical recording medium and supplied with current to generate a magnetic field, A cooling unit that is attached to the lens with a predetermined distance from the generating element and that does not obstruct the optical path at the optical axis end and that is located inside the outer peripheral end of the lens. Heat generated by the magnetic field generating element is transmitted to the cooling member via the lens. Therefore, it is possible to prevent the temperature from increasing due to the magnetic field generating element.

Further, in the method of manufacturing an optical pickup according to the present invention, the portion of the magnetic field generating element supporting substrate, which is an optical member provided with the magnetic field generating element, having a predetermined distance from the magnetic field generating element, A cooling means for attaching the cooling means so that the side end does not obstruct the optical path and is located inside the outer peripheral end of the lens; and a lens on which the light from the light source enters the magnetic field generating element support substrate. Since the cooling member is attached to the member and has a supporting substrate attaching step of forming the lens, the cooling member is attached to the lens at a short distance from the magnetic field generating element without obstructing the optical path. Accordingly, it is possible to provide an optical pickup device in which heat generated by the magnetic field generating element is transmitted to the cooling member via the lens, and a rise in temperature due to the magnetic field generating element is prevented.

Further, the magneto-optical disk drive according to the present invention has a lens for converging light from a light source on the magneto-optical recording layer of the optical recording medium, and a lens disposed on a surface facing the optical recording medium. A magnetic field generating element to which a current is supplied to generate a magnetic field, and which is attached to the lens at a predetermined distance from the magnetic field generating element, so that the optical axis side end does not obstruct the optical path and the outer peripheral end of the lens The heat generated by the magnetic field generating element is transmitted to the cooling member via the lens. Therefore, it is possible to prevent the temperature from increasing due to the magnetic field generating element.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an optical element included in a magneto-optical disk device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of the magneto-optical disk device.

FIG. 3 is a diagram showing a configuration of a head of the magneto-optical disk device.

FIG. 4 is a plan view showing a coil portion of the optical element.

FIG. 5 is a flowchart showing a manufacturing process of the magneto-optical lens unit.

FIG. 6 is a view showing the coil unit,
FIG. 4 is a cross-sectional view taken along a line A.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Magneto-optical disk drive, 41 front lens, 44 coil support board, 46 coil part, 51 wiring member

Continuation of the front page (72) Inventor Akira Suzuki 6-35 Kita Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F-term (reference) 5D075 AA03 CF03 CF10 EE03 5D119 AA50 BA01 JA43 JA49 MA30 NA01 NA03

Claims (30)

[Claims] 1. A lens for converging light from a light source to a magneto-optical recording layer of an optical recording medium, and a lens is disposed on a surface of the lens facing the optical recording medium, and a current is supplied to generate a magnetic field. A magnetic field generating element to be mounted, attached to the lens at a predetermined distance from the magnetic field generating element, an end on the optical axis side does not obstruct the optical path, and is located inside the outer peripheral end of the lens An optical pickup device comprising: a cooling unit. 2. The optical pickup device according to claim 1, wherein said cooling means comprises a wiring member having a wiring for supplying a current to at least said magnetic field generating element. 3. The optical pickup device according to claim 2, wherein at least a part of the wiring is provided outside an outer peripheral surface of the lens. 4. The wiring member is provided with the wiring on a front surface of the substrate which is close to the optical recording medium and a back surface which is far from the optical recording medium, and the wiring on the front surface is connected to the wiring on the back surface. The optical pickup device according to claim 2, wherein 5. The optical pickup device according to claim 4, wherein a current supply wiring for supplying a current to the magnetic field generating element is connected to the wiring on the back surface. 6. The optical pickup device according to claim 1, wherein said cooling means is made of a high heat conductive member having a value larger than the heat conductivity of said lens. 7. The lens comprises: a magnetic field generating element support substrate formed of an optical member provided with the magnetic field generating element; and a lens member to which light from the light source is incident. 2. The optical pickup device according to claim 1, wherein the generating element supporting substrate is attached to a back surface side of the optical recording medium that is farther than the opposing surface. 8. An optically transparent liquid is filled between the magnetic field generating element supporting substrate and the lens member, and the magnetic field generating element supporting substrate and the lens member are optically joined. The optical pickup device according to claim 7, wherein 9. The cooling means has a substantially flat plate shape, and the thickness of the portion of the magnetic field generating support substrate forming an optical path located inside the inner peripheral end of the cooling means has a thickness in the optical axis direction. ,
8. The optical pickup device according to claim 7, wherein said cooling means is formed to be thicker than the thickness in the optical axis direction. 10. The optical pickup device according to claim 9, wherein said cooling means is mounted in contact with said magnetic field generating element support substrate. 11. The optical pickup device according to claim 2, wherein an outer diameter of the wiring member is larger than an outer diameter of the lens. 12. The lens comprises a plurality of lens members arranged on an optical path of light for irradiating the optical recording medium, and the cooling means is arranged on the optical recording medium among the plurality of lens members. The optical pickup device according to claim 1, wherein the optical pickup device is attached to a close lens member. 13. A lens for converging light from a light source on a magneto-optical recording layer of an optical recording medium, and a magnetic field generating means for supplying a current to a surface of the lens facing the optical recording medium to generate a magnetic field. A method for manufacturing an optical pickup device for manufacturing an optical pickup including an element, wherein a portion of the magnetic field generating element support substrate, which is an optical member provided with the magnetic field generating element, has a predetermined distance from the magnetic field generating element A cooling means attaching step of attaching a cooling means such that the end on the optical axis side does not obstruct the optical path and is located inside the outer peripheral end of the lens; and removing the magnetic field generating element support substrate from the light source. A step of attaching the supporting substrate to the lens member on which the light is incident to constitute the lens. Law. 14. The method of manufacturing an optical pickup device according to claim 13, wherein said cooling means comprises a wiring member having a wiring for supplying a current to at least said magnetic field generating element. 15. The cooling means has a substantially flat plate shape, and in the cooling means attaching step, a thickness of a portion forming an optical path located inside an inner peripheral end of the cooling means in an optical axis direction. 2. The cooling device according to claim 1, wherein the cooling device is attached to the magnetic field generating element support substrate formed to be thicker than the thickness of the cooling device in the optical axis direction.
4. The method for manufacturing the optical pickup device according to item 3. 16. The method of manufacturing an optical pickup device according to claim 13, wherein in the supporting substrate attaching step, the magnetic field generating element supporting substrate is optically integrally attached to the lens member. . 17. An optically transparent liquid is filled between the magnetic field generating element support substrate and the lens member to optically integrate the magnetic field generating element and the lens member. A method for manufacturing the optical pickup device according to claim 16. 18. The method according to claim 18, wherein the lens includes a plurality of lens members disposed on an optical path of light for irradiating the optical recording medium. In the supporting substrate attaching step, the optical recording medium among the plurality of lens members is provided. Attaching the cooling means to the lens member closest to the lens member, and after the supporting substrate attaching step, attaching the lens member to which the magnetic field generating element supporting substrate is attached to another optical lens member. 14. A method for manufacturing an optical pickup device according to item 13. 19. A rotation driving means for driving an optical recording medium to rotate, a light source for emitting light toward the optical recording medium, and a lens for converging light from the light source to a magneto-optical recording layer of the optical recording medium. A magnetic field generating element which is disposed on a surface of the lens facing the optical recording medium and is supplied with current to generate a magnetic field, and which is attached to the lens at a predetermined distance from the magnetic field generating element. An optical element having an optical axis side end that does not obstruct the optical path and cooling means positioned inside the outer peripheral end of the lens; and a light receiving element that receives return light reflected by the optical recording medium. And a signal processing means for generating a predetermined signal based on the return light received by the light receiving means. 20. The magneto-optical disk drive according to claim 19, wherein said cooling means comprises a wiring member provided with a wiring for supplying a current to at least said magnetic field generating element. 21. The magneto-optical disk drive according to claim 20, wherein at least a part of the wiring is provided outside an outer peripheral surface of the lens. 22. The wiring member, wherein the wiring is provided on a front surface of the substrate that is close to the optical recording medium and a back surface that is far from the optical recording medium. 21. The magneto-optical disk drive according to claim 20, wherein: 23. The magneto-optical disk drive according to claim 22, wherein a current supply wiring for supplying a current to the magnetic field generating element is connected to the wiring on the back surface. 24. The magneto-optical disk drive according to claim 19, wherein said cooling means is made of a high heat conductive member having a value larger than the heat conductivity of said lens. 25. The lens, comprising: a magnetic field generating element support substrate made of an optical member provided with the magnetic field generating element; and a lens member to which light from the light source is incident. 20. The magneto-optical disk device according to claim 19, wherein the magneto-optical disk device is mounted on a back surface of the generating element supporting substrate farther from the optical recording medium than the opposing surface. 26. An optically transparent liquid is filled between the magnetic field generating element supporting substrate and the lens member, and the magnetic field generating element supporting substrate and the lens member are optically joined. 26. The magneto-optical disk device according to claim 25, wherein: 27. The cooling means has a substantially flat plate shape, and the thickness of the portion of the magnetic field generating support substrate forming an optical path located inside the inner peripheral end of the cooling means has a thickness in the optical axis direction. ,
26. The magneto-optical disk device according to claim 25, wherein the thickness of the cooling means is greater than the thickness in the optical axis direction. 28. The magneto-optical disk drive according to claim 27, wherein said cooling means is mounted in contact with said magnetic field generating element support substrate. 29. The magneto-optical disk drive according to claim 20, wherein an outer diameter of the wiring member is larger than an outer diameter of the lens. 30. The lens, comprising: a plurality of lens members arranged on an optical path of light for irradiating the optical recording medium; wherein the cooling means is disposed on the optical recording medium among the plurality of lens members. 20. The magneto-optical disk device according to claim 19, wherein the magneto-optical disk device is attached to a near lens member.