WO2005057570A1 - Magnetooptic head - Google Patents

Abstract

A magnetooptic head comprising a lens member (1) for forming a light spot on a disc (D) and provided with a coil (12) having a surface opposite to the disc (D) and forming a magnetic field perpendicular to the disc (D), characterized in that the opposite surface of the lens member (1) has a central region (13a) and a circumferential region (13b) retracting from the central region (13a) in the direction of the optical axis (L2) of the lens member (1), and a cushion material (14) is laid at least in the circumferential region (13b) and composed of a material having a thermal conductivity higher than that of the air.

Description

 Specification

 Magneto-optical head Technical field

 The present invention relates to a magneto-optical head used for recording / reproducing data on / from a magneto-optical disk. Background art

 There is a magnetic field modulation recording method for recording data on a magneto-optical disk (hereinafter simply referred to as a “disk”). A conventional magneto-optical head employing this magnetic field modulation recording system has a configuration as shown in FIG. 10 as an example. The magneto-optical head shown in the figure includes a lens member 100 that forms a laser spot on the recording layer 88 of the disk D. On the surface of the lens member 100 facing the disk D, there is a central area 100a through which the laser beam passes, and below the central area 100a, the recording layer 88 of the disk D is located. Thus, a coil 120 for applying a vertical magnetic field is formed. The coil 120 is formed on the substrate 110 and is covered with the dielectric film 130. The outer surface of the dielectric film 130 is formed on the opposing surface 100 0 of the lens member 1. a. A lens 111 is provided on a surface of the substrate 110 opposite to the disk D side.

According to the magneto-optical head shown in FIG. 10, the recording layer 88 of the disk D is relatively close to the recording layer 88 on the side facing the lens member 100, and the magnetic field applying coil 12 0 is located. Therefore, the size of the coil 120 can be reduced, and the inductance of the coil can be reduced as much as possible. As a result, a sufficient magnetic field can be applied to the recording layer 88 of the disk D while suppressing the power supplied to the coil 120. Further, according to the magneto-optical head, the laser beam passes through the center 120 c of the coil 120 integrated with the lens member 100, and the laser spot is formed on the recording layer 88 of the disk D. It is formed. Therefore, the numerical aperture of the lens member 1 is restricted by the size (the inner diameter of the coil) of the center 120 c of the coil 120. Therefore, in order to reduce the laser spot regardless of the numerical aperture, the disk D and the magneto-optical The distance from the head (hereinafter, referred to as “disk-to-head distance”) is defined as an extremely small distance. In particular, for the distance g of the disturbing head formed along the optical axis L2 of the lens member 100, the laser beam reflected by the recording layer 88 of the disc D is detected during the rotation of the disc D, and based on that, By controlling the position of the magneto-optical head in the direction of the optical axis, the control is performed so as to keep a substantially minute interval. The smaller the distance g of the disturb head is, the more easily the lens member 100 and the disc D come into contact with each other. For example, while the disk D is rotating, the entire magneto-optical head is moved in the radial direction of the disk D by tracking control and seek control. At this time, as shown in FIG. 11, the facing surface force s of the lens member 100 may be inclined with respect to the surface of the disk D, and the outer peripheral edge 100 b of the facing surface may be inclined. The area near the surface of disk D is し ゃ. If the facing surface of the lens member 100 is a circle $$, its radius is 2 mm, and the disk head spacing g at the center is 30 μm, the surface of the disk D and the lens member 100 If the angle Θ with the opposing surface is 15 mrad or more, the outer peripheral end 100 b of the opposing surface comes into contact with the surface of the disk D. Such contact also occurs due to the fluctuation of the surface of the disk D rotating at a high speed, the unevenness of the insulating protective film 89 that forms the surface of the disk D, the assembly tolerance of the magneto-optical head, and the like. The opposing surface of 0 and the surface of the disc D will be scratched.

As a configuration for preventing such damage due to contact, for example, there is a configuration disclosed in Japanese Patent Application Laid-Open No. 2002-184014. In the configuration disclosed in FIG. 4 of the publication, the central region of the facing surface of the lens member protrudes toward the disk, and the peripheral region therearound is formed so as to extend in the optical axis direction to form a slope. . According to such a configuration, the opposing surface of the lens member, in particular, the vicinity of the outer periphery of the opposing surface is less likely to come into contact with the disk surface. Therefore, it is possible to prevent the opposing surface of the lens member and the surface of the disc from being damaged. Further, in the configuration disclosed in FIG. 7 of the publication, the entire opposing surface of the lens member is formed as a flat surface, and a rubber or the like which repels a parasite with the disk is provided near the outer periphery of the opposing surface. Elastic body is provided. According to such a configuration, even if the facing surface of the lens member is tilted with respect to the surface of the disk, the elastic body will be woven on the surface of the disk. It is possible to prevent the isk from being damaged.

 However, even if the configuration disclosed in the above publication is simply applied to a magneto-optical head, as described below, the heat radiation efficiency of the heat generated in the coil is reduced, and damage due to contact is sufficiently prevented. There was a disadvantage that I could not do it.

 Generally, in a magneto-optical head of the magnetic field modulation recording type, a high-frequency current flows through a coil, and a large amount of heat is generated in the coil. At this time, a high-speed airflow is generated between the facing surface of the lens member and the surface of the disk as the disk rotates. The high-speed airflow actively cools the facing surface of the lens member, and the heat generated by the coil is released to the outside (in the air) from the facing surface of the lens member. Such a high-speed air flow improves as the distance between the disk and the head decreases. In other words, the heat radiation efficiency depends on the distance between the disk and the head. The smaller the distance between the disk and the head, the higher the heat radiation efficiency.

 However, when the peripheral region on the facing surface of the lens member is an inclined surface, the head-to-disk spacing in the peripheral region becomes larger than the disk-head spacing in the central region. As a result, the heat radiation efficiency in the peripheral region was lower than that in the central region, and the heat radiation efficiency as a whole was reduced. When the heat radiation efficiency is reduced in this manner, heat is likely to be stored in the lens member, and the optical characteristics of the lens member, for example, the refractive index may be changed by the heat. Therefore, it was necessary to prevent a decrease in the heat radiation efficiency in order to reduce the laser spot as much as possible to achieve a high recording density.

 On the other hand, when the opposing surface of the lens member is formed as a flat surface and an elastic body is provided near the outer periphery of the opposing surface, the disk-head distance in the central region is extremely small. Instead, the distance between the elastic body and the disk becomes narrower. As a result, the elastic body was removed from the surface of the disk, and the frequency increased, and the elastic body was worn down, possibly resulting in damage to the lens member and the disk. Disclosure of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a magneto-optical head capable of preventing a decrease in heat radiation efficiency while sufficiently preventing damage caused by a parasite with a disk. According to the present invention, a magneto-optical head having a lens member that forms a light spot on a disk, has a surface facing the disk, and has a force and a coil for forming a perpendicular magnetic field on the disk. Wherein the facing surface of the lens member has a central region and a peripheral region extending in the optical axis direction of the lens member beyond the central region, and at least the peripheral region includes a buffer. The material is laminated, and the cushioning material is formed of a material having a higher thermal conductivity than air.

 In a preferred embodiment, the buffer material is formed of a predetermined resin so that the Vickers hardness is 30 to 35 HV.

 In a preferred embodiment, the peripheral region is provided with one or a plurality of step portions so that the peripheral region is set to β in the optical axis direction of the lens member more than the central region.

 In a preferred embodiment, the cushioning member is formed so as to have a smooth outer surface continuous with the central region while filling the step portion. In a preferred embodiment, the mild material has a smooth outer surface that fills in the stepped portion, and gradually moves in the optical axis direction of the lens member toward the outer periphery of the peripheral region. Is formed.

 In a preferred embodiment, the cushioning member is formed such that an inner peripheral portion thereof extends to a peripheral portion of the central region.

 In a preferred embodiment, the peripheral region is inclined so that the amount gradually increases as the distance from the central region increases.

 In a preferred embodiment, the mild material is formed so as to have a smooth outer surface extending in the optical axis direction of the lens member toward the outer periphery of the peripheral region.

Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings. Brief Description of Drawings

 FIG. 1 is a sectional view showing a first embodiment of a magneto-optical head according to the present invention. FIG. 2 is an enlarged sectional view of a main part of FIG.

 FIG. 3 is a cross-sectional view of a main part for describing the operation of the magneto-optical head according to the first embodiment.

 FIG. 4 is a cross-sectional view of a principal part showing a second embodiment of the magneto-optical head according to the present invention. FIG. 5 is a fragmentary cross-sectional view showing a manufacturing step of the magneto-optical head according to the second embodiment.

 FIG. 6 is a fragmentary cross-sectional view showing a manufacturing step of the magneto-optical head according to the second embodiment.

 FIG. 7 is a sectional view of a principal part showing a third embodiment of the magneto-optical head according to the present invention. FIG. 8 is a sectional view of a principal part showing a fourth embodiment of the magneto-optical head according to the present invention. FIG. 9 is a cross-sectional view of a principal part showing a fifth embodiment of the magneto-optical head according to the present invention. FIG. 10 is a sectional view of a main part showing a conventional magneto-optical head.

 FIG. 11 is a cross-sectional view of a main part for describing the operation of a conventional magneto-optical head. BEST MODE FOR CARRYING OUT THE INVENTION

Figure:! 1 to 3 show the first embodiment of the magneto-optical head according to the present invention. The magneto-optical head of this embodiment is for recording data on a magneto-optical disk (hereinafter, simply referred to as a “disk”) D by a magnetic field modulation recording method and for reproducing the data. This is for applying a perpendicular magnetic field to the recording layer 88 while forming a laser spot on the recording layer 88 of the disk D. As shown in FIG. 1, the magneto-optical head H includes a first lens member 1 facing a surface of the disk D on which the recording layer 88 is provided (the lower surface of the disk D in FIG. 1). And a second lens member 2 located on the opposite side of the first lens member 1 from the disk D side. These first and second lens members 1 and 2 are held in a lens holder 30 so as to overlap in the thickness direction of the disc D. The lens holder 30 is a carriage 7 having a built-in mirror 7 1 built-in. Mounted on 0. Among the first and second lens members 1 and 2, the first lens member 1 includes a plano-convex lens 10 and a substrate 1 1, a magnetic field applying coil 12, a dielectric film 13, and a squeezing material 14 are integrated. The other second lens material 2 is composed of a biconvex lens. The surface of the recording layer 88 of the disk D is covered with an insulating protective film 89 having a light-transmitting property. The Vickers hardness on the surface of the insulating protective film 89 is about 35 to 40 HV. The disk D and the magneto-optical head H are arranged such that a very small specified interval (hereinafter referred to as “disk-to-head interval”) is formed between the disk D and the disk D during rotation. Be placed.

 As shown in FIG. 1, the lens holder 30 is supported by the carriage 70 via supporting means (not shown) that can be displaced in the tracking direction (radial direction) of the disk D indicated by the arrow Tg. It is possible to displace in the same direction. The lens holder 30 can be displaced in the focus direction indicated by an arrow Fc by, for example, the driving force of the electromagnetic driving means 31. The first lens member 1 is held on the disk D side of the lens holder 30 that can also be displaced in the tracking direction, and the second lens member 2 is placed on the lower rising mirror 7 1 side. Is held.

The carriage 70 is movable in the tracking direction Tg by, for example, a driving force of a voice coil motor (not shown). By the movement of the carriage 70, a seek operation for disposing the lens holder 30 near the target track is performed. The laser light travels from the fixed optical section, which is shown in the figure and has a laser diode, a collimator lens, etc., toward the carriage 70, and reaches a rising mirror 71 mounted on the carriage 70. The laser light reflected upward by the rising mirror 71 is focused by being incident on the second lens member 2 and the first lens member 1 in this order. This forms a laser spot on the recording layer 88 of the disk D. The fixed optical section is also provided with a beam splitter / photodetector, and when the laser light is reflected by the recording layer 88, the The reflected light is detected by the photodetector The control microcomputer (not shown) controls the tracking error signal and the focus error signal from the photodetector while the disk D is rotating. The position of the magneto-optical head H is finely adjusted in the tracking direction T g and the focus direction F c based on the optical axis L 2 of the first lens member 1. The disk head spacing g formed along During the rotation of the disk D, the distance is generally kept at a specified value, and the laser spot is positioned on a predetermined track to maintain the track state (see FIG. 2). The disc head gap g on the optical axis L2 is specified to be, for example, about 30 μm. However, the distance between the disk and the head at a position shifted from the optical axis L2 fluctuates due to the relative inclination between the rotating disk D and the magneto-optical head H.

 As best shown in FIG. 2, the first lens member 1 has a coil 12 for applying a magnetic field, a dielectric film 13, and a cushioning material 14 on the upper surface side of the substrate 11 on the disk D side. And a plano-convex lens 10 is adhered to the lower surface of the substrate 11. The substrate 11 is made of, for example, glass of the same material as the plano-convex lens 10. Such a first lens member 1 has a thickness in the up-down direction in the figure, has a diameter in the left-right direction in the figure, and is formed entirely in a disk shape.

 The magnetic field applying coil 12 is formed on the substrate 11 by patterning a metal film such as copper into a predetermined shape, and can be formed by a thin film forming process. The coil 12 has a central portion 12c through which the laser beam passes, and a central axis L1 passing through the central portion 12c is substantially equal to the optical axis L2 of the first lens member 1. It is formed as follows. The coil 12 has two layers overlapping in the direction of the central axis L1, and each layer has windings 12a and 12b formed in a spiral pattern. The windings 1 2a and 1 2b of each layer have their outermost ends drawn out to the outside of the first lens member 1, and the drawn-out portions are terminals for supplying power to the coils 1 and 2. (Not shown). The windings 12a and 12b of each layer are connected to each other via an intermediate layer so that the innermost ends of the windings are conductive (not shown). A high-frequency current flows through such a coil 12, the direction of the magnetic field generated by the coil 12 is switched accordingly, and a magnetic field is applied perpendicularly to the recording layer 88 of the disk D. At this time, in the coil 12, reheating occurs due to the application of the high-frequency current. Most of this heat is transferred to the dielectric film 13. Note that the number of layers is not limited to two, but may be only one if it can generate a magnetic field of a desired strength, or may be three or more.

The dielectric film 13 is made of a translucent silicon oxide aluminum or silicon oxide. It is made of electrical material and can be formed by a thin film forming process. The dielectric film 13 is formed on the substrate 11 so as to cover the entirety of the coil 12, and has a facing surface having a circular shape in plan view when viewed from the disk D side. The opposing surface of the dielectric film 13 is lower than the central region 13 a by providing a central region 13 a covering the upper part of the coil 12 and a step 13 c on the outer periphery of the central region 13 a. And a peripheral region 13b formed so as to form a surface. Specifically, the central region 13a on the opposing surface of the dielectric film 13 slightly protrudes toward the disk D side from the upper portion of the coil 12 and is formed as a flat surface layer facing the disk D. Have been. The peripheral region 13 b on the opposing surface of the dielectric film 13 is retracted in the direction of the optical axis L 2 of the first lens member 1 from the central region 13 a, and is annular in plan view. It is formed so as to form a step surface. The step 13c is located at the boundary between the central region 13a and the peripheral region 13b, and is formed at least outside the outermost periphery of the coil 12. On the outer surfaces of the peripheral region 13b and the stepped portion 13c, a cushioning material 14 is laminated.圣 r of the central area 13a corresponding to the dimension from the optical axis L2 of the first lens member 1 to the step 13c, and the dimension from the optical axis L2 to the outer peripheral edge of the peripheral area 13b The corresponding judgment of the entire opposing surface and the thickness t of the stepped portion 13c are formed to be, for example, r = 2 mm, R = 4 mm, and t = 15 m¾g, respectively. The refractive index of such a dielectric film 13 is preferably substantially the same as the refractive index of the plano-convex lens 10 or the substrate 11.

The buffer material 14 is made of a material softer than the insulating protective film 89 formed on the surface of the disk D, for example, a novolak resin, fluororesin, or silicone rubber used as a resist, and is formed by a thin film forming process. It is possible. The cushioning material 14 is laminated so as to cover the entire area of the peripheral area 13 b on the opposing surface of the dielectric film 13 and fill the step 13 c. The outer surface of the buffer material 14 facing the disk D is formed so as to be substantially flush with the central region 13a. Therefore, the thickness of the cushioning material 14 is almost equal to the thickness t of the step portion 13c. However, as can be seen in FIG. 2, near the outer peripheral end of the peripheral region 13b, a part of the outer surface of the cushioning material 14 is not rounded and has a rounded chamfered shape. Is formed. Such a buffer material 14 is softer than the surface of the insulating protective film 89 of the disk D, and has a Vickers hardness of, for example, 30 to 35 H @ ¾. Is formed. Also, since the buffer material 14 has an order of magnitude higher than that of air, the heat dissipation is less than that of bringing the peripheral region 13 b into direct contact with air. The surface of the disk D, that is, the surface of the insulating protective film 89 is brought into contact with the outer surface of the buffer material 14 by the relative inclination of the rotating disk D and the magneto-optical head H. It will be.

 Next, the operation of the magneto-optical head H will be described.

 When writing data to the disk D by operating the magneto-optical head H by the magnetic field modulation recording method, the laser beam is intermittently applied onto the target track in the recording layer 88 while rotating the disk D. To raise the predetermined magnetic material of the recording layer 88 to the Curie level. The laser light is guided so as to converge on the recording layer 88 of the disk D through the center 咅 12 c of the coil 12 in the first lens member 1.

 At this time, a large amount of heat is generated in the coil 12 with the passage of the high-frequency current. Further, a high-speed airflow is generated between the disk D and the first lens member 1 as the disk D rotates. The surface of the insulating protective film 89 in the disk D is constantly deprived of heat by the high-speed air flow, and the surface is kept almost constant. On the other hand, in the first lens member 1, the central region 13a of the dielectric film 13 and the outer surface of the cushioning material 14 are actively cooled by the high-speed air flow, and the coil The heat generated in 12 is efficiently released into the air through the central region 13a and the cushioning material 14.

 Here, as a model of the authors, it is assumed that the cushioning material is not laminated in the peripheral region of the dielectric film, and that the peripheral region is exposed to be directly removed by the high-speed air flow. . In this case, the heat dissipation Q per unit area in the peripheral region is theoretically expressed by the following equation (1). Here, assuming that the surface of the disk has a constant temperature and infinite heat capacity, the surface temperature of this disk is TO, the surface temperature of the peripheral region is Tl, the distance between the disk surface and the peripheral region is d, and the air is Let a be the thermal conductivity of The distance d between the surface of the disk and the peripheral region is, on average, the sum of the disk-to-head distance (g) and the thickness of the step (t).

 Q = (T 1— T O) X λ a / d (1)

On the other hand, as in the present embodiment, when the cushioning material 14 In the case of the heat transfer model described above, of the distance d between the surface of the disk D and the peripheral region 13b, the thickness t of the stepped portion 13c and the looseness of the radiative conductivity λ Can be regarded as being replaced with As a result, in the present embodiment, the heat release amount Q 'per unit area in the peripheral region 13b is expressed by the following equation (2).

 Q '= (T 1 TO) XX a / (d + (λ a / λ- 1) X t) (2) where λ is the thermal conductivity of air. The ratio is about one digit larger than λa. Therefore, comparing the above two formulas (1) and (2), the heat dissipation Q when the cushioning material 14 is present is larger than the heat dissipation Q when there is no loose goods. The heat dissipation efficiency is improved by around 30%. Even if it is assumed that a material having a thermal conductivity larger than the thermal conductivity λ of the buffer material 14 is laminated in the peripheral region, the conductivity of such a material is calculated by the above equation ( The amount of heat radiation obtained by substituting into 2) is not so different from the amount of heat radiation Q 'of ^ according to the present embodiment, and a dramatic improvement in heat radiation efficiency cannot be expected. As a result, even the cushioning material 14 having a lower thermal conductivity λ than metal or the like effectively works to increase the heat radiation efficiency of the peripheral region 13b. Therefore, the heat generated in the core 12 quickly moves toward the central region 13a and the cushioning material 14, and is efficiently released from the central region 13a and the cushioning material 14 into the air. It is. In other words, heat is not easily transmitted to the substrate 11 ゃ plano-convex lens 10.

 On the other hand, as a mechanical operation, the magneto-optical head H is moved in the tracking direction Tg by a seek operation while the disk D is rotating. At this time, as shown in FIG. 3, the surface facing the first lens member 1 with respect to the surface of the disk D; the posture becomes inclined; when the inclination angle Θ increases to some extent, the outer surface of the cushioning material 14 Contact the surface of the insulating protective film 89 on the disk D. Such contact may also be caused by the run-out of the disk D rotating at a high speed, the insulation of the disk D, the unevenness of the disk D, the assembly tolerance of the magneto-optical head H, and the like.

The mild material 14 has a thickness equal to the thickness t of the stepped portion 13 c and is substantially flush with the central region 13 a, so that the inclination angle ま で becomes a predetermined angle. The cushioning material 14 will not insult on the surface of disk D. As is well shown in FIG. 3, when the inclination angle に な る exceeds a predetermined angle, the cushioning material 14 is elastically deformed toward the surface of the disk D. At this time, on the surface of the disc D, the upper or peripheral area of the step 13c The disk D never touches the outer edge of 13b. As a result, even if the cushioning material 14 is turned to the surface of the disk D, the contact portion of the buffer 14 is elastically deformed and absorbs the impact of the parasite. The insulating film 13 and the facing surface of the first lens member 1 are not damaged by the dielectric film 13. In addition, even if the cushioning material 14 violently collides with the surface of the disk D, and a part of the outer surface of the cushioning material 14 is shaved, the shavings adhere to the surface of the disk D. The surface of the disk D is not scratched. Such shavings of the mild material 14 can be removed by cleaning the surface of the disk D. Therefore, according to the magneto-optical head の of the present embodiment, the cushioning material 14 can sufficiently prevent the disk D from being damaged by infestation. In addition, the heat generated by the coil 12 is efficiently released from the buffer material 14 and the central region 13a of the dielectric film 13 so that the heat radiation efficiency of the first lens member 1 is reduced. Can be prevented. As a result, the optical characteristics of the first lens member 1, for example, the refractive index does not change due to heat, and the recording density of the disk D is increased by making the laser spot as small as possible. Can be.

 4 to 9 show another embodiment of the magneto-optical head according to the present invention. In these figures, the same or similar elements as those of the magneto-optical head of the above embodiment are denoted by the same reference numerals as those of the above embodiment.

In the magneto-optical head of the second embodiment shown in FIG. 4, a step 13 d is further provided on the outer periphery of the peripheral region 13 b of the dielectric film 13, and the step 13 d Are formed so as to be needled up to the substrate 11. The buffer material 14 is formed so as to cover the peripheral region 13 b of the dielectric film 13 up to the peripheral region 11 a of the substrate 11. A heat radiator 40 having the same thickness as the coil 12 is formed annularly between the outer periphery of the coil 12 and the cushioning material 14. The heat radiator 40 is made of, for example, the same metal as the coil 12, and efficiently transmits heat generated by the coil 12 to the central region 13 a of the dielectric film 13 and the buffer material 14. Play a role. The first lens member 1 having such a configuration can be manufactured by a thin film forming process as follows. First, as shown in FIG. 5 (a), a resist is applied on a substrate 11 serving as a base, exposed and developed, and then covered with the resist. After growth, the resist is removed. As a result, on the substrate 11, the lower layer side winding 12 b of the coil 12, the lower layer 40 a of the radiator (the lower layer portion of the radiator 40), and the metal layer 50 for securing the formation area of the buffer material 14 are formed. a is formed.

 Next, as shown in FIG. 5 (b), the dielectric layer 13a (the dielectric material S) is sputtered so as to cover the winding Hl 2b, the heat sink lower layer 40a, the metal layer 50a, and the substrate 11. 13 lower layer). After that, these surfaces are flattened, and the same treatment is performed using the above-mentioned resist, whereby the intermediate layer 12 d of the coil 12, the radiator intermediate layer 40 b (the middle part of the radiator 40), and the region A metal layer 50b for securing is formed. The middle layer 12d of the coil 12 serves to connect the two windings 12a and 12b, which are divided into upper and lower layers.

 Next, as shown in FIG. 5 (c), a dielectric layer 13b (an intermediate portion of the dielectric film 13) is formed by sputtering, and then, as shown in FIG. The surface of the dielectric layer 13b is flattened by P treatment (chemical polishing). Further, as shown in FIG. 5 (e), by performing the same processing as described above, the winding H 12a of the upper layer j of the coil 12, the radiator upper layer 40 c (the upper layer portion of the radiator 40), and the area : A protective metal layer 50c is formed.

 Next, as shown in FIG. 6A, a dielectric layer 13c (the upper layer portion of the dielectric film 13) is formed by the same processing as described above, and a metal layer 50d for securing an area is formed. Thereafter, as shown in FIG. 6B, a dielectric layer 13d (a portion to be a surface layer of the dielectric film 13) is formed by sputtering. As shown in FIG. 6 (c), the dielectric layer 13d and the metal layer 50d are polished so that the surfaces are flattened by, for example, a CMP process and the thickness is reduced as much as possible. Finally, as shown in FIG. 6 (d), the metal layers 50 a to 50 d for storage are removed by, for example, dissolving, and the removed portions are mixed with the buffer material 14 by spin coating. (Not shown). For example, a photoresist is used as a material to be the insulating material 14, and the photoresist is heat-treated at a high temperature of, for example, about 200 ° C. After that, a plano-convex lens 10 (not shown) is bonded to one surface of the substrate 11. Thus, the first lens member 1 can be easily manufactured.

According to such a configuration, the heat generated in the coil 12 is radiated through the radiator 40 to the dielectric. It is efficiently transmitted to the central region 13 a of the body membrane 13 and the cushioning material 14. Therefore, the heat radiation efficiency of the first lens member 1 is increased, and the temperature rise of the coil 12 can be effectively prevented.

 In the magneto-optical head according to the third embodiment shown in FIG. 7, the outer surface of the loose type 4 14 is continuous with the central region 13 a, but the optical axis L 2 increases toward the outer periphery of the peripheral region 13 b. It is formed so that the amount of retreat in the direction becomes large. That is, the outer surface of the cushioning member 14 is inclined with respect to the flat central region 13a. According to such a configuration, it is possible to keep the disk D and the cushioning member 14 in contact as little as possible. In the magneto-optical head of the fourth embodiment shown in FIG. 8, three step portions 13 c to 13 e are formed in the peripheral region 13 b of the dielectric film 13 so as to form three steps. Is provided. Each section of the week region 13b is lower as it is closer to the outer periphery. In addition, the outer surface of the cushioning material 14 has a larger amount in the optical axis L2 direction toward the outer periphery of the peripheral region 13b, and forms an inclined surface with respect to the flat central region 13a. It is formed as follows. The cushioning material 14 fills the steps 13c to 13e to cover the entire peripheral region 13b, but the inner peripheral portion 14a extends to the peripheral portion of the central region 13a. It extends and slightly protrudes to the disk D side. In other words, the inner peripheral portion 14a of the cushioning material 14 covers the outer peripheral edge of the central region 13a that is likely to be a portion that is likely to damage the disk D.

 According to such a configuration, it is possible to prevent the center region 13a of the dielectric film 13 from being in contact with the disk D, and it is possible to more reliably prevent damage due to the scattering of the disk D.

In the magneto-optical head of the fifth embodiment shown in FIG. 9, the peripheral region 13 b of the dielectric film 13 has a larger amount of retreat in the direction of the optical axis L 2 toward the outer periphery, and is flat. It is formed so as to form a slope with the central area 13a. The cushioning material 14 is laminated so as to have a substantially uniform thickness with respect to the inclined peripheral region 13b. As a result, the outer surface of the cushioning material 14 increases in the amount of β in the direction of the optical axis L2 toward the outer periphery of the peripheral region 13b, and has an inclined surface like the peripheral region 13b. Has become. The inner peripheral portion 14a of the cushioning member 14 extends to the peripheral portion of the central region 13a and slightly protrudes to the disk D side. The peripheral portion of the central region 13a covered by the inner peripheral portion 14a of the cushioning material 14 is smoothly connected to the peripheral region 13b. Yes.

 According to such a configuration, when the surface of the disk D comes into contact with the inner peripheral portion 14a of the cushioning member 14, the inner peripheral portion 14a is greatly elastically deformed, and the surface of the disk D is in the central region. May be ig-T up to the periphery of 13a. Even in such a state, the surface of the disk D is scarcely scratched because there is no angular portion near the peripheral portion of the central region 13a, so that the disk D comes into contact with the disk D. Damage can be effectively prevented.

 Note that the content of the present invention is not limited to the above embodiment. The specific configuration of each part of the magneto-optical head according to the present invention can be variously changed in design.

 For example, as a modified example of each of the first and third to fifth embodiments, similarly to the configuration of the second embodiment, a configuration in which a heat radiator is provided outside the outer periphery of the coil may be used. Further, in common with each of the first to fifth embodiments, a magnetic body for strengthening a magnetic field generated by the coil may be provided between the coil and the substrate.

Claims

The scope of the claims 1. A magneto-optical head having a lens member that forms a light spot on a disk, has a surface facing the disk, and has a coil for forming a perpendicular magnetic field on the disk,  The facing surface of the lens member includes a central region, and a peripheral region that extends from the central region in the optical axis direction of the lens member.  A magneto-optical head, characterized in that a buffer material is laminated at least on the peripheral region and the buffer material is formed of a material having a higher thermal conductivity than air. 2. The magneto-optical head according to claim 1, wherein the EI mating material is formed of a predetermined resin so as to have a Vickers hardness of 30 to 35 HV. 3. The magneto-optical device according to claim 1 or 2, wherein the peripheral region is provided with one or more step portions so that the peripheral region is made to extend more in the optical axis direction of the lens member than the central region. Good. 4. The magneto-optical bead according to claim 3, wherein the loose rag is formed so as to have a smooth outer surface continuous with the central region while filling the step. 5. The buffer material is formed so as to have a smooth outer surface extending in the optical axis direction of the lens member toward the outer periphery of the peripheral region while filling the step portion. The magneto-optical head according to claim 3. 6. The magneto-optical head according to claim 5, wherein the horn material is formed so that an inner peripheral portion thereof extends to a peripheral portion of the central region. 7. The magneto-optical head according to claim 1, wherein the peripheral region is inclined so as to gradually increase in flatness as the distance from the central region increases. 8. The optical fiber according to claim 7, wherein the material is formed so that the material has a smooth outer surface which becomes β in the optical axis direction of the lens member toward the outer periphery of the peripheral region. ¼Head.