JP3207678B2 - Optical information recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording / reproducing apparatus and, more particularly, to an objective lens driving apparatus for an optical information recording / reproducing apparatus for optically writing or reading information on a disk-shaped recording medium. .

[0002]

2. Description of the Related Art An optical information recording / reproducing apparatus for optically reproducing information from a disk-shaped recording medium such as a magneto-optical disk, or optically recording information on a disk-shaped recording medium, employs a rotating recording medium. A light beam is condensed on a medium to record information at a desired position or to reproduce recorded information. When recording / reproducing information in this way, a focus shift due to the rise and fall of the warp of the disc-shaped recording medium and a tracking shift due to the eccentricity of the disc-shaped recording medium occur. In order to correct these deviations, the objective lens for converging the light beam is moved in a direction perpendicular to the recording medium surface (hereinafter, referred to as a focus direction F) and a direction parallel to the recording medium surface. It is necessary to drive the recording medium in the radial direction (hereinafter, referred to as tracking direction T).

In recent years, portable and personalized optical information recording / reproducing devices such as mini disk players and data file devices using magneto-optical disks have been strongly desired. Therefore, in order to move the objective lens in the two directions of the focus direction F and the tracking direction T as described above, it is required that the objective lens driving device be further reduced in size, in particular, thinner.

FIG. 23 is a sectional view showing an example of the configuration of a conventional objective lens driving device, and FIG. 24 is an exploded perspective view thereof.
In these figures, the objective lens 1 is held by a lens holder 2, and the optical axis of the objective lens 1 coincides with the focus direction F. Further, the position where the light beam 12 that has passed through the objective lens 1 is collected is determined from the design of the objective lens 1. Therefore, the objective lens 1 is arranged at a distance from the surface of the disk 15 by a certain distance. A magnetic yoke 3b is fixed to the base 10, and a magnet 4b is attached to the lens holder 2 at a position facing the magnetic yoke 3b. A focus coil 5b and a tracking coil 6b are wound around the magnetic yoke 3b, and form a magnetic circuit together with the magnetic yoke 3b and the magnet 4b. The lens holder 2 moves in the focus direction F or the tracking direction T by the driving force generated by the magnetic circuit. The lens holder 2 is supported by elastic members 7a to 7d. These elastic members 7a to 7d are arranged to be substantially parallel to each other, and one end of each elastic member is connected to the printed circuit board 8a,
The other end is attached to the printed circuit board 8c via the fixing member 9 via the fixing member 9. Thus, the lens holder 2 is elastically supported by the elastic members 7a to 7d, and
Fixed to

[0005] A base 10 of the objective lens driving device is mounted on an optical table 13. In addition to the objective lens driving device described above, a light source that emits a light beam 12 and a reflection mirror 11 that deflects the light beam 12 and enters the objective lens 1 are provided on the optical bench 13. Disk 1
A circuit for receiving the light beam reflected by 5 and detecting an error signal for focus control and tracking control using the light beam and information recorded on the disk 15 is also provided on the optical bench 13. .

The disk 15 is housed in a cartridge 14. The cartridge 14 has a focus direction F
A window 14 a having a length W in a direction perpendicular to both the tracking direction T and the tracking direction T is provided, and the light beam 12 is irradiated onto the disk 15 through the window 14 a.

In order to reduce the overall thickness of the optical information recording / reproducing apparatus, it is desirable that the objective lens driving device be housed in the window 14a of the cartridge 14. This is because the objective lens driving device is the thickest among the components provided on the optical bench 13 and the total thickness H3 of the optical bench 13 and the objective lens driving device (from the lower surface of the cartridge 14 to the bottom surface of the optical bench 13). This is because reducing the distance) leads to a reduction in the thickness of the entire device. However, since the length W of the window 14a is very small, for example, about 17 mm for a mini-disc, the entire objective lens driving device is mounted on the window 1a.
It is difficult to fit in 4a.

Therefore, in the conventional optical information recording / reproducing apparatus, as shown in FIG. 23, in order to reduce the thickness of the objective lens driving device and the optical table 13, the lens holder 2 is attached to the mounting portion of the objective lens 1 as shown in FIG. Make it protruding shape,
Further, the reflection mirror 11 is arranged so as to bite into the lower part of the lens holder 2, that is, the upper end thereof is located higher than the lowermost end of the lens holder 2.

The correction of the focus shift and the correction of the tracking shift are performed by moving the lens holder 2 holding the objective lens 1 and the magnet 4b in the focus direction F and the tracking direction T, respectively. A driving force can be generated by an electrodynamic converter composed of the focus coil 5b, the magnetic yoke 3b, and the magnet 4b, whereby the lens holder 2 can be moved in the focus direction F. In addition, a driving force can be generated by an electrodynamic converter composed of the tracking coil 6b, the magnetic yoke 3b, and the magnet 4b, whereby the lens holder 2 can be moved in the tracking direction T. The lens holder 2 is parallel to each other 4
Since it is supported by the elastic members 7a to 7d,
In both the focus direction F and the tracking direction T, the lens holder 2 moves while keeping the optical axis of the objective lens 1 perpendicular to the surface of the disk 15.

[0010]

However, the objective lens driving device having the structure shown in FIG. 23 has a problem that the stability of servo control such as focus control and tracking control is impaired. This is because displacement of the center of gravity of the movable portion including the objective lens 1, the lens holder 2, the magnet 4b, and the printed circuit boards 8a and 8b is displaced from the point of application of the driving force generated by the electrodynamic converter. This is because the frequency characteristics are disturbed. In order to solve such a problem, for example, as shown in FIG. 25, an electrodynamic converter is provided on both sides of the lens holder 2 in the direction in which the light beam 12 is incident on the reflection mirror 11. Therefore, the center of the driving force generated at the two positions and the center of gravity of the movable portion may be arranged so as to coincide with each other. However, in the objective lens driving device shown in FIG. 25, although stable frequency characteristics can be obtained, the reflection mirror 11 cannot be cut into the lower part of the lens holder 2 as shown in FIG. This is because if the reflection mirror 11 is cut into the lower part of the lens holder 2 where the objective lens 1 is attached, the reflection mirror 11
A part of the optical path of the light beam 12 incident on the magnetic yoke 3
a, because they are blocked by the drive coils 5a and 6a. Therefore, in the objective lens driving device having the configuration shown in FIG. 25, the thickness H2 is larger than the thickness H3, so that a reduction in thickness cannot be achieved.

When an optical information recording / reproducing apparatus provided with such an objective lens driving device is used as a portable device, an access operation to a disk is performed in a state where the tracking direction T and the gravity direction are almost coincident. Could be done. Usually, the access operation is performed in a state where the tracking control is not performed, and in such a case, the movable portion is shifted from the neutral position of the movable portion by its own weight. Therefore, in order to perform accurate tracking control,
In consideration of the displacement of the movable part, the movable range of the movable part must be large, and the beam diameter of the light beam 12 incident on the reflection mirror 11 must be large. It is a big obstacle.

SUMMARY OF THE INVENTION The present invention has been made in view of such a situation, and an objective lens driving device capable of reducing the overall thickness of an optical bench and an objective lens driving device and having a stable displacement frequency characteristic. SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical information recording / reproducing apparatus provided with:

[0013]

The invention according to claim 1 of the present application is an optical information recording / reproducing apparatus for optically writing or reproducing information on a disk-shaped recording medium, comprising: a base; An objective lens whose beam is focused on a disk-shaped recording medium and whose optical axis is arranged perpendicular to the recording medium, and an objective lens for moving the objective lens in the direction of the optical axis of the light beam and in the radial direction of the recording medium. An objective lens driving device, and an optical member that causes a light beam passing between the objective lens driving device and the base to enter a recording medium via the objective lens, and the objective lens driving device includes the objective lens. Holding means elastically held on the base, and first and second electrokinetic conversion means for driving the holding means in the direction of the optical axis of the objective lens and in the radial direction of the recording medium. And the first and second movements Type conversion unit, across the retaining means
And the first electrokinetic conversion means is provided with a second conductor.
The first conductivity type conversion is made closer to the recording medium by the type conversion means.
A light beam is configured to pass between the means and the base.
It is characterized in that the.

In the invention of claim 2 of the present application, the distance between the first electro-dynamic conversion means and the base is larger than the distance between the second electro-dynamic conversion means and the base. Things.

According to the third aspect of the present invention, the first and the second
The electrokinetic conversion means has a magnet, a magnetic yoke, and a plurality of drive coils arranged in a magnetic field generated by the magnet and the magnetic yoke.

According to the invention of claim 4 of the present application, the magnet is provided on the holding means, the magnetic yoke is fixed to the base, and the first and second electrodynamic conversion means have the first and second electrodynamic conversion means. 2
Is disposed at a position where the driving force is generated symmetrically with respect to the center of gravity of the movable part including the objective lens, the holding means, and the magnet.

According to the invention of claim 5 of the present application, the drive coil is provided on the holding means, the magnetic yoke is fixed to the base, and the first and second electrodynamic conversion means have the first and second electrodynamic conversion means. The second driving force is disposed at a position where the second driving force is generated symmetrically with respect to the center of gravity of a movable portion including the objective lens, the holding unit, and the driving coil.

According to the invention of claim 6 of the present application, the objective lens driving device further includes a fixing member fixed to the base, and a plurality of elastic members for elastically supporting the holding means. The elastic members are substantially parallel to each other;
Each has a first end attached to the holding means and a second end attached to the fixing member.

According to the seventh aspect of the present invention, the plurality of elastic members include four elastic members. Of the elastic members, two spring constants close to the recording medium and two other spring constants are set. Are different from each other.

In the invention of claim 8 of the present application, the elastic member is
The first end is closer to the recording medium than the second end,
The center of the movable portion, which is the center of the end, is aligned with the center of the driving force by the driving coil.

According to the ninth aspect of the present invention, the magnet of the first electrodynamic conversion means and the magnet of the second electrodynamic conversion means are:
The different magnetic poles are arranged so as to face each other.

According to the tenth aspect of the present invention, the length of the magnet of the first electro-dynamic conversion means in the optical axis direction is longer than the length of the magnet of the second electro-dynamic conversion means in the optical axis direction. It is small.

According to the eleventh aspect of the present invention, the holding means has a magnetic member disposed between the magnet of the first electrodynamic conversion means and the magnet of the second electrodynamic conversion means. Is what it is.

In the twelfth aspect of the present invention, the holding means has an aperture for narrowing the light beam incident on the objective lens to a predetermined diameter, and the aperture is a part of a magnetic member. is there.

According to a thirteenth aspect of the present invention, the plurality of drive coils include an optical axis direction drive coil for moving the objective lens in the optical axis direction and a radial direction drive coil for moving the objective lens in the radial direction. Drive coil.

In the fourteenth aspect of the present invention, the radial drive coil is divided in the radial direction and wound around the magnetic yoke.

In the invention according to claim 15 of the present application, the fixing member and the holding means have substrates for attaching the first and second ends of the plurality of elastic members, respectively.

In the invention according to claim 16 of the present application, the substrate is a printed circuit board, the plurality of elastic members are metal wires, and the first and second ends of the elastic member are soldered to the printed circuit board. It is.

In the seventeenth aspect of the present invention, the substrate is a metal plate, the plurality of elastic members are metal wires, and the first and second ends of the elastic member are soldered to the metal plate. It is.

According to the eighteenth aspect of the present invention, the holding means has a concave portion or a convex portion for positioning the magnet on the holding means.

According to the nineteenth aspect of the present invention, each of the plurality of elastic members has a cross section different in thickness and width.

In the twentieth aspect of the present invention, one of the first and second ends of the plurality of elastic members is bent.

In the invention of claim 21 of the present application, the plurality of elastic members are L-shaped leaf springs.

According to the invention of claim 22 of the present application, the fixing member has a groove for positioning the second end of the elastic member.

In the invention according to claim 23 of the present application, the fixing member has a substrate for attaching the second end of the elastic member, and the groove is provided in the substrate.

In the invention according to claim 24 of the present application, the groove portion is provided with a tapered portion.

In the invention according to claim 25 of the present application, the substrate is insert-molded on the holding means and the fixing member.

According to the twenty-sixth aspect of the present invention, the fixing member has a concave portion for accommodating a plurality of elastic members, and the concave portion is filled with a viscoelastic material which is cured by irradiating ultraviolet rays. Is what it is.

In the invention according to claim 27 of the present application, the concave portion of the fixing member is provided with a taper.

According to a twenty-eighth aspect of the present invention, a notch is provided near a portion of the base to which the fixing member is fixed.

According to the twenty-ninth aspect of the present invention, the elastic member has a rod shape, and the holding means has a substantially conical hole for positioning the first end of the elastic member. It is.

According to the thirtieth aspect of the present invention, the elastic member has a rod shape, and the fixing member has a substantially conical hole for positioning the second end of the elastic member. It is.

According to the invention of claim 31 of the present application, the elastic member is rod-shaped, and the holding means is provided with a substantially cylindrical hole for positioning the first end of the elastic member. The central axis of each of the holes makes a predetermined angle with respect to the longitudinal direction of the elastic member.

In the invention according to claim 32 of the present application, the second end of the elastic member has a larger diameter than other portions of the elastic member.

According to the invention of claim 33 of the present application, the material of the holding means is a liquid crystal polymer.

In the invention of claim 34 of the present application, the holding means further has an adhesive receiving portion filled with an adhesive for bonding the side surface of the objective lens to the holding means.

[0047]

In the optical information reproducing apparatus of the present invention, the first and second electrodynamic conversion means are arranged on both sides of the holding means for holding the objective lens. These electrokinetic conversion means generate driving force on both sides of the holding means,
The center of the driving force coincides with the center of gravity of the movable part including the objective lens, the holding means, and the like. For this reason, even when the objective lens is driven, the displacement frequency characteristics are not disturbed, and stable servo control can be realized. Further, the first electrokinetic conversion means is farther from the base than the second electrokinetic conversion means, and the light beam passes between the first conductivity type conversion means and the base without being interrupted. Incident on the optical member. Therefore, according to the present invention, it is possible to realize an objective lens driving device which is thinner than a conventional objective lens driving device provided with a plurality of electrokinetic conversion means.

Further, as the elastic member for fixing the holding means to the fixing member mounted on the base, a member having a flat shape whose width is larger than the thickness of its cross section is used. Here, the thickness of the cross section of the elastic member corresponds to the width of the elastic member in the focus direction, and the width of the cross section corresponds to the width of the elastic member in the tracking direction. Accordingly, even when the access operation is performed in a state where the tracking direction and the gravity direction match, the extent to which the position of the movable portion is displaced by its own weight can be suppressed. Therefore, the movable range of the movable part can be reduced, and therefore, it is not necessary to set the diameter of the light beam large in consideration of the fact that a part of the optical path of the light beam is blocked by the movable part as in the related art. As a result, the thickness of the objective lens driving device can be reduced.

[0049]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an optical information recording / reproducing apparatus according to the present invention.
Note that the same components are denoted by the same reference symbols throughout the drawings. FIG. 1 is an exploded perspective view showing a configuration of a first embodiment of an objective lens driving device, FIG. 2 is a plan view showing a positional relationship between the objective lens driving device of FIG. 1 and a window of a cartridge, and FIG. FIG. 2 is a sectional view taken along line AA of FIG. As shown in FIG. 3, the objective lens 1 has a lens holder 2 so that its optical axis is perpendicular to the surface of the disk 15, that is, the optical axis of the objective lens 1 and the focus direction F coincide. Is held in. An adhesive receiving portion 100 is provided on the upper surface of the lens holder 2.
The objective lens 1 is fixed to the lens holder 2 by the adhesive filled in the adhesive receiving portion 100. Lens holder 2
Means that the portion where the objective lens 1 is provided is the disk 15
It is formed so as to protrude to the side. As a material of the lens holder 2, for example, a liquid crystal polymer is used. When the lens holder 2 is formed by injection-molding a liquid crystal polymer, it is possible to realize a higher displacement frequency characteristic. As shown in FIGS. 1 and 2, printed circuit boards 8 a and 8 b are provided on the side surface of the lens holder 2 so as to sandwich the lens holder 2 in the tracking direction T. One ends of elastic members 7a and 7b are attached to the printed board 8a, and one ends of elastic members 7c and 7d are attached to the printed board 8b. These four elastic members 7 a to 7 d are arranged substantially parallel to each other, and the other ends thereof are attached to a fixing member 9 fixed to the base 10. Thus, the lens holder 2 is fixed to the fixing member 9 by the elastic members 7a to 7d.

The base 10 of the objective lens driving device is fixed to an optical bench 13. In addition to the objective lens driving device, the optical bench 13 includes a light source (not shown) that generates a light beam 12 such as a semiconductor laser, and a reflection mirror 11 that is an optical member that deflects the light beam 12 and makes the light beam 12 enter the objective lens 1. Installed. In addition, a circuit for receiving the light beam reflected by the disk 15 and detecting a signal for servo control such as a focus error signal and a tracking error signal based on the light beam and a signal representing information recorded on the disk 15 is also provided. , On the optical bench 13.

Now, the light beam 12 emitted from the light source is
The light enters the reflection mirror 11 via an optical system (not shown), is deflected by the reflection mirror 11, and enters the objective lens 1. The light beam 12 incident on the objective lens 1 is focused on the disk 15 through the window 14a of the cartridge 14. Thereby, the information recorded on the disk 15 is read out optically, or the information is optically written on the disk 15. Subsequently, the light beam 12 is
The reflected light is passed through the objective lens 1 and the reflecting mirror 11 in this order, and is incident on a circuit (not shown) for detecting a servo signal and an information signal. A servo signal and an information signal are detected based on the incident light beam 12. In this manner, the recording of information on the disk 15 and the reproduction of the information are performed. However, these are all performed by using a known method, and are not the subject of the present invention, so that the description thereof is omitted.

In the objective lens driving device of the present invention, the lens holder 2 is formed in such a shape that the portion where the objective lens 1 is provided protrudes toward the disk 15. A reflection mirror is provided below the portion of the lens holder 2 where the objective lens 1 is provided (hereinafter, referred to as a protruding portion) such that the upper end of the reflection mirror 11 is closer to the disk 15 than the lowermost end of the lens holder 2. 11 are arranged.

In addition to the objective lens 1, the lens holder 2
Two magnets 4a and 4b are attached to the side surface. The magnet 4a applies a light beam 12 to the reflecting mirror 11 at the protrusion.
The magnet 4b is mounted on the opposite side (the right side in FIGS. 2 and 3) of the lens holder 2 in a direction perpendicular to both the focus direction F and the tracking direction T. It is attached. Therefore, as shown in FIG. 3, the magnet 4a is displaced from the magnet 4b in the focus direction F. As the magnets 4a and 4b, two magnets made of the same material and having the same size are used. These two magnets are arranged such that the opposite poles are opposite to each other.
If it is a pole, the magnet 4b is arranged so that the objective lens 1 side is the S pole. In this way, the information is canceled at the position of the disk 15 and does not adversely affect the recording and reproduction of information.

At positions facing the magnets 4a and 4b, magnetic yokes 3a and 3b around which a focus coil and a tracking coil are respectively wound are arranged.
Both are fixed to the base 10. The base 10 has a flat plate portion fixed on an optical bench 13, and a reflection mirror 11 is disposed at the center thereof. Reflection mirror 1 of base 10
At the end opposite to the fixing member 9 with respect to 1, a U-shaped opening surrounding the optical path of the light beam 12 incident on the reflection mirror 11 is formed. Also, the light beam 12 of the base 10
Thick portions are formed on both sides of the optical path. The magnetic yoke 3a is arranged so as to straddle both thick portions. The thickness of the thick portion is determined so that the optical path of the light beam 12 is not blocked by the magnetic yoke 3a.

As described above, in the objective lens driving device according to the present invention, the electrokinetic converter including the magnetic yoke, the driving coil, and the magnet is disposed on both sides of the lens holder 2 so that the optical path of the light beam 12 is not blocked. Are provided so as to be shifted from each other. As a result, a driving force is generated on both sides of the lens holder 2. The center of these driving forces is determined by the objective lens 1, the lens holder 2, and the printed circuit board 8a.
And 8b and the center of gravity of the movable part composed of the magnets 4a and 4b. Specifically, for example, the lens holder 2
Is designed such that the center of gravity of the movable part is located at the center of a line connecting the center of the magnet 4a and the center of the magnet 4b. If the center of the movable part does not seem to coincide with the center of the driving force generated on both sides of the lens holder 2, the driving force may be reduced by increasing the weight of the lens holder 2 itself to lower the center of gravity of the movable part. And the center of gravity of the movable part.

In the objective lens driving device of the present embodiment, the correction of the focus deviation and the tracking deviation is performed in the same manner as in the conventional objective lens driving device shown in FIG. 23, by the focus coils 5a and 5b and the tracking coils 6a and 6b.
Is driven to move the lens holder 2 in the focus direction F and the tracking direction T. However, in this embodiment, unlike FIG. 23, two electrodynamic converters are provided on both sides of the lens holder 2 so that the centers of the driving forces respectively generated by the two electrodynamic converters coincide with the centers of the movable parts. Since the type converter is provided, stable displacement frequency characteristics can be obtained, and stable servo control can be performed. Further, the two electrokinetic converters are shifted from each other in the focus direction F, and the electrokinetic converter on the side where the light beam 12 is incident on the reflection mirror 11 is disposed closer to the disk 15 than the other electrodynamic converter. are doing. Therefore, the thickness (distance from the lower surface of the cartridge 14 to the bottom surface of the optical bench 13) H1 of the entire apparatus including the optical bench 13 is reduced to only one electrodynamic converter for thinning as shown in FIG. It can be the same as the thickness H3 when provided.

However, even if the centers of the driving forces generated at two points by the electrodynamic converter coincide with the center of gravity of the movable portion, if the centers of the elastic members 7a to 7d are shifted from the support center of the lens holder 2 side. In addition, the movable portion is inclined by a moment generated when the movable portion is driven. For example, when the support center of the elastic members 7a to 7d on the lens holder 2 side and the center of the driving force are shifted in the focus direction F, a moment is generated when the movable part is driven in the tracking direction T. The moment tilts the movable part and causes deterioration of optical performance. Therefore, in such a case, the center of the driving force and the center of support of the elastic members 7a to 7d must be matched.

For this reason, as shown in FIG.
7d to the lens holder 2 may be shifted closer to the disk 15 than the attachment positions of the elastic members 7a to 7d to the fixing member 9. Then, the center of support of the elastic members 7a to 7d can be matched with the center of gravity of the movable part. In this case, simply use the elastic members 7a to 7d.
It is only necessary to adjust the mounting position of the movable member on the lens holder 2, so that the center of gravity of the movable portion and the support center of the elastic members 7a to 7d can be matched without affecting the thickness of the entire device.

In order to prevent the inclination of the movable portion due to the moment, the relative relationship between the spring constants of the elastic members 7a to 7d may be changed. Elastic members 7a to 7d
When the center of the support center and the driving force is shifted in the focusing direction F, the relative relationship between the spring constant of the elastic member 7a and 7b, as well as to change the relative relationship between the spring constant of the elastic member 7c and 7d Set . For example, the elastic member 7a
Disk 1 is closer to the center of the driving force than the support center
5, the upper elastic member 7a,
The spring constant of 7c is set to be larger than the spring constants of the lower elastic members 7b and 7d, respectively . By adjusting the spring constant of the elastic member in this manner, it is possible to cancel the inclination of the movable part when the movable part is driven, and maintain stable optical performance.

As described above, by adjusting the spring constants of the elastic members 7a to 7d or the mounting positions thereof, the thickness of the entire optical information recording / reproducing apparatus including the objective lens driving device and the optical table 13 is increased. In addition, the center of gravity of the movable portion including the objective lens 1, the lens holder 2, the magnets 4a and 4b, and the printed boards 8a and 8b, the center of the driving force, and the support centers of the elastic members 7a to 7d can be easily matched. . Therefore, when the movable part is driven, the optical performance is not degraded due to the inclination of the movable part, and a stable displacement frequency characteristic is obtained, so that stable servo control can be performed.

In the first embodiment, the magnets 4a and 4
b are arranged so that different poles face each other. Therefore, although the distance between the magnet 4a and the disk 15 is shorter than the distance between the magnet 4b and the disk 15, the magnet 4a
The effect of the magnetic field generated by the magnetic field on the disk 15 can be suppressed to some extent. However, the magnetic force of the magnet 4b farther from the disk 15 is made larger than that of the magnet 4a closer thereto, and the magnetic flux generated by both magnets is
In the vicinity of the recording surface, the magnets 4
The effect of the magnetic field generated by a on the disk 15 can be further reduced. As an example, FIG. 5 shows a case where the size of the magnet 4b is larger than that of the magnet 4a.
If the materials of the magnets used as the magnets 4a and 4b are the same, the magnetic field generated by the magnet 4b can be increased by increasing the size of the magnet 4b farther from the disk 15 as shown in FIG. . as a result,
The magnetic fluxes of the magnets 4a and 4b cancel each other in the vicinity of the recording surface of the disk 15, so that the magnets 4a and 4b do not affect the light spot formed on the disk 15.

FIG. 5 shows an example in which magnets of the same material are used as the magnets 4a and 4b. However, when magnets of different materials are used, the magnet having the larger magnetic force is used as the magnet 4b and the disk 15 is used. Needless to say, the same effect can be obtained by arranging it farther from the camera.

The effect of the magnetic field generated by the magnets 4a and 4b on the disk 15 can also be reduced by attaching the magnetic material 16 to the lens holder 2 at a position between the magnets 4a and 4b as shown in FIG. Can be. The shape of the magnetic material 16 is not limited to the shape shown in FIG. 6, but can reduce the influence of the magnetic field generated by the two magnets 4a and 4b on the disk 15 and reduce the influence of the reflecting mirror 11
Any shape may be used as long as it does not block the optical path of the light beam incident on the objective lens 1 from. FIG. 6 shows, as an example of the shape of the magnetic material 16, a case where the magnetic material 16 is used as an aperture for reducing the diameter of a light beam incident on the objective lens 1. In this case, the diameter of the light beam can be reduced with strict accuracy without providing an aperture separately from the magnetic material 16. Also, without using the magnetic material 16 as an aperture, a part of the lens holder 2 is formed into a shape that functions as an aperture,
It is also possible to provide an aperture in the lens holder 2 separately from the magnetic material 16. Further, by changing the weight and shape of the magnetic material 16, the center of gravity of the movable portion can be easily adjusted.

As described above, in the first embodiment, two electrokinetic converters are provided on both sides of the lens holder 2, and the electrokinetic converter on the side where the light beam 12 enters the reflecting mirror 11 is the other. Is closer to the disk 15 than the electro-dynamic type converter. Therefore, it is possible to reduce the thickness of the objective lens driving device and the entire optical bench without interrupting the optical path of the light beam 12 and securing stable displacement frequency characteristics.

Next, consider further reducing the thicknesses of the objective lens driving device and the optical bench as a whole. In the first embodiment, the magnetic yoke 3 in which the focus coil 5a and the tracking coil 6a are wound above the light beam 12
Since a is located, the distance between the center of the light beam 12 and the lower surface of the magnetic yoke 3a needs to be secured by a predetermined distance t1, as shown in FIG. However, the first
As shown in FIG. 8, in a magnet drive type objective lens driving device in which a magnet is attached to a movable portion and a coil is wound directly around a fixed magnetic yoke as shown in the embodiment of FIG. 8, a tracking coil 6a is connected to coils 6x and 6y. The magnetic yoke 3a may be divided, and each may be wound in half by leaving the center part of the magnetic yoke 3a. By doing so, the distance between the center of the light beam 12 and the lower surface of the magnetic yoke 3a can be reduced to t2, and the thickness can be further reduced. As described above, the tracking coil 6a is divided into the coils 6x and 6y, and the electrodynamic converter located above the optical path of the light beam 12 is divided into the magnet 4a, the focus coil 5a, and the tracking coil 6a.
x and a converter composed of a magnetic yoke 3a and a converter composed of a magnet 4a, a focus coil 5a, a tracking coil 6y and a magnetic yoke 3a. Can be further reduced.

In the first embodiment, the elastic members 7a to 7a
As d, a metal wire made of a copper compound such as phosphor bronze is used. FIG. 9 shows an example of the shape of the ends of the elastic members 7a to 7d on the fixing member 9 side. The ends of the elastic members on the side of the fixing member 9 are crushed so that the flat stopper portions 2 are formed.
Let it be 2 . If the elastic members 7a to 7d having such stoppers 22 are dropped from the holes through which the elastic members 7a to 7d of the printed circuit board 8c pass at the time of manufacturing the objective lens driving device, the ends of the stoppers 22 are formed as holes. Each of the elastic members 7a to 7d is positioned with respect to the printed board 8c in the longitudinal direction.

As the printed circuit boards 8a to 8c to which the elastic members 7a to 7d are directly attached, a metal plate made of a copper compound such as phosphor bronze may be used.
Then, the elastic members 7a to 7d and the printed circuit boards 8a to 8
c can be fixed by soldering. This makes it easier to assemble the objective lens driving device, simplifies the manufacturing process, and at the same time improves reliability.

Further, if the printed boards 8a and 8b are insert-molded on the lens holder 2 and the printed board 8c is insert-molded on the fixing member 9, the ease of assembling the objective lens driving device is further improved. When the lens holder 2 is formed by injection molding using a liquid crystal polymer, insert molding of the substrate becomes easier. Note that the ease of assembly can be further improved by simultaneously molding the protrusions or grooves for positioning the magnets 4a and 4b on the lens holder 2.

In the first embodiment and its modified examples, a magnet driven type objective lens driving device in which a magnet is attached to a movable portion and a focus coil and a tracking coil are directly wound around a fixed magnetic yoke is taken as an example. As described above, the same effect as that described in the present embodiment can be obtained in a coil drive type objective lens driving device in which a focus coil and a tracking coil are attached to a movable portion and a magnet and a magnetic yoke are fixed.

Next, a second embodiment of the objective lens driving device of the optical information recording / reproducing device of the present invention will be described with reference to the drawings. FIG. 10 is a perspective view showing a configuration of the objective lens driving device, and FIG. 11 is an exploded perspective view for explaining an assembling state thereof. FIG. 12 is a plan view of the objective lens driving device of FIG. 10, and FIG. 13 is a sectional view taken along line BB of FIG. The objective lens driving device according to the present embodiment is a magnet driving type in which a magnet is attached to a movable part and a focus coil and a tracking coil are wound around a fixed magnetic yoke, as in the first embodiment described above. Since it is almost the same as the first embodiment, a detailed description is omitted.

In the objective lens driving device of the present embodiment, the correction of the focus shift due to the warpage of the disk moving up and down with the rotation of the disk and the correction of the tracking shift due to the eccentricity of the disk are the same as those in the first embodiment. Similarly, this is performed by driving the objective lens 1 in the focus direction F and the tracking direction T. That is, in the focus direction F, the objective lens 1 is composed of the first yoke 3a, the magnet 4a, and the focus coil 5a.
Of the lens holder 2 having the magnets 4a and 4b attached thereto by using the driving force generated by the electrokinetic converter of the above and the second electrokinetic converter including the magnetic yoke 3b, the magnet 4b and the focus coil 5b. It is driven by translation. In the tracking direction T, the magnetic yokes 3a and 3b, the magnets 4a and 4b, and the tracking coil 6
By moving the movable portion in parallel with the driving force generated by the electro-dynamic converter composed of
Is driven.

What is different from the first embodiment in the objective lens driving device of the present embodiment is the shape of the metal wire used as the elastic members 7a to 7d. As described above, in the conventional objective lens driving device, when an access operation to the disc is performed in a state where the tracking direction T and the gravity direction are almost coincident, the movable part is shifted from the neutral position by its own weight. There is. On the other hand, in the objective lens driving device of the present embodiment, in order to suppress the displacement of the movable portion, the spring constant in the tracking direction T is set to such an extent that the metal wire as the elastic member is not largely bent by the weight of the movable portion. Up to.

To increase the spring constant of the elastic members 7a to 7d, it is conceivable to increase the diameter of the elastic members as one method. However, when the diameter of the elastic member is increased, not only the spring constant in the tracking direction T but also the spring constant in the focus direction F is increased, and the sensitivity of the focus control that requires higher sensitivity and precision than the tracking control is required. Will fall. Therefore, in this embodiment, a metal wire in which only the spring constant in the tracking direction T is increased is used as the elastic member without changing the spring constant in the focus direction F from that of the first embodiment.

FIGS. 14 to 16 show the elastic member 7 of this embodiment.
The example of the shape of the cross section of a-7d is shown. 14 shows a rectangular shape, FIG. 15 shows an elliptical shape, and FIG. 16 shows a cross-sectional shape obtained by rolling a circular wire, for example. As shown in FIGS. 14 to 16, in this embodiment, the elastic members 7 a to 7 d
Since the width w (width in the tracking direction T) is somewhat larger than the thickness t (width in the focus direction F) and a metal wire having a flat cross section is used, the tracking direction T almost coincides with the gravity direction. Even when the access operation is performed in the state, the displacement of the movable portion due to its own weight can be suppressed. Therefore, it is not necessary to increase the movable range of the movable part in consideration of the displacement of the position of the movable part in the tracking direction T, or to increase the diameter of the light beam 12 incident on the reflection mirror 11. It is possible to reduce the thickness.

The cross-sectional shapes of the elastic members 7a to 7d are shown in FIG.
4, the ellipse shown in FIG. 15, or the rectangle shown in FIG.
It is not limited to any of the shapes shown in the above, and the width of the cross section w is larger than the thickness t to such an extent that the elastic member can realize a spring constant that does not bend significantly due to the weight of the movable portion. If so, the same effects as those described above can be obtained.

Specifically, how much the width a of the cross section of the elastic members 7a to 7d is larger than the thickness w is determined by various factors such as the weight of the movable part. Actually, the thickness t is set to about 100 μm, and the width w is set to be twice or less the thickness t, that is, the width w and the thickness t are set so as to satisfy the relationship of t ≦ w ≦ 2t. For example, when a metal wire having a cross section thickness t of 0.07 mm and a width w of 0.11 mm is used as the elastic members 7a to 7d, the displacement of the movable portion in the focus direction F due to its own weight is 0.28 mm. On the other hand, the displacement of the movable portion due to its own weight in the tracking direction T can be suppressed to 0.12 mm.

However, by increasing the spring constant of the elastic member in the tracking direction T, the displacement of the movable member in the tracking direction T due to its own weight is reduced, but the movable member is moved when the elastic member itself moves in the hole of the printed circuit board 8c. In the tracking direction T. Therefore, it is necessary to position the elastic members 7a to 7d so that each of the elastic members 7a to 7d does not move in the tracking direction T in the corresponding hole of the printed circuit board 8c.

FIG. 17 shows the elastic members 7a to 7a in this embodiment.
FIG. 9 is a perspective view illustrating a method of attaching 7d to a fixing member 9. In this embodiment, as shown in FIG.
Each end of 7d is bent in the focus direction F to form a bent portion 17. The elastic member is positioned by sandwiching the bent portions 17 of the elastic members 7a to 7d in a groove portion 18 having a width substantially equal to the width of the bent portion 17 provided on the fixed member 9 in the tracking direction. Groove 18
Is formed with a tapered portion 19 from the opening to the middle of the groove. If only the elastic members 7a to 7d are dropped into the holes of the printed circuit board 8c with a certain degree of accuracy while the longitudinal directions of the elastic members 7a to 7d and the direction of gravity coincide with each other, the respective bent portions 17 fall into the groove portions 18. The elastic members 7a to 7d are fixed to the printed circuit board 8c by the engagement between the groove 18 and the bent portion 17. By such a method, the positioning of the elastic members 7a to 7d in the tracking direction T can be performed very easily.

As the elastic members 7a to 7d, instead of a metal wire having one end bent as shown in FIG.
The same effect can be obtained by using a leaf spring molded into a hook shape by etching, pressing or the like. As shown in FIG. 17, instead of providing the groove 18 on the side surface of the fixing member 9 on which the printed circuit board 8c is mounted, the printed circuit board 8c is provided.
A similar effect can be obtained also when a metal plate is used as the material and the groove is formed integrally with the metal plate.

FIG. 19 shows that the elastic members 7 a to 7
The state of attachment of 7d is shown. In this embodiment, the fixing member 9 is used.
Is provided with a space 23. The elastic members corresponding to each of the space portions 23 are inserted, and the elastic members 7a to 7d protruding from the space portion 23 are sandwiched by the groove portions 18.
7d is positioned and fixed. The space 23 is filled with an ultraviolet-curable viscoelastic agent in order to reduce the Q value at the primary resonance frequency. The viscoelastic agent in the space 23 is
Notch 2 provided near fixing member 9 of base 10
The resin is cured by the ultraviolet light irradiated from Step 4. If the space 23 is provided with a taper as shown in FIG. 22, the elastic members 7 a to 7 d do not come into contact with the fixed member 9 even when the movable portion is moved in the focus direction F.

Further, as shown in FIG.
When the tapered guide portion 20 is provided at the opening of the positioning hole 21 into which the elastic members 7a to 7d are inserted, the attachment of the elastic members 7a to 7d to the lens holder 2 becomes easier. In the case where such a guide portion 20 is provided, if each of the elastic members 7a to 7d is dropped into the guide portion 20 in a state where the longitudinal direction and the direction of gravity coincide, the respective ends of the elastic members 7a to 7d are The corresponding positioning hole 21 is recessed. Thereby, the ends of the elastic members 7 a to 7 d are fixed to the lens holder 2.

The axis of the cylindrical positioning hole 21 is shown in FIG.
As shown in FIG. 1, it does not have to coincide with the longitudinal direction of each elastic member. For example, as shown in FIG.
May be provided on the lens holder 2 such that its axis forms a predetermined angle with the longitudinal direction of each elastic member. In this case, the clearance between each of the elastic members having the diameter a and the positioning hole 21 having the diameter b becomes smaller than the clearance ba in FIG. 21 and becomes b′-a. Thereby, the elastic members 7a to 7
The positioning accuracy of d is improved.

[0083]

As described above, in the optical information recording / reproducing apparatus according to the present invention, a plurality of electrokinetic conversion means in the objective lens driving apparatus are replaced by the driving force generated by these electrokinetic conversion means. They are arranged on both sides of the movable part so that the center and the center of the movable part coincide. As a result, the displacement frequency characteristics are not disturbed, and stable servo control can be performed. Further, the electrokinetic conversion means on the side where the light beam is incident on the reflection mirror is arranged closer to the recording medium than other electrokinetic conversion means. Therefore, the optical path of the light beam is not interrupted by the electrokinetic conversion means, and the thickness of the objective lens driving device and the entire optical bench is reduced despite the provision of a plurality of electrokinetic conversion means. be able to.

According to the seventh aspect of the present invention, the elastic member is made of four elastic members, and the spring constant close to the recording medium is made different from other spring constants, so that the support center of the elastic member is shifted from the center of the driving force. In this case, the inclination of the moment generated when the motor is driven can be canceled.

According to the invention of claim 8, the center of support of the elastic member on the movable portion side is made to coincide with the center of the driving force. For this reason, there is obtained an effect that a tilt due to a moment does not occur and stable optical performance can be maintained.

According to the ninth aspect of the present invention, since the different magnetic poles of the magnets of the first and second drive type conversion means are opposed to each other, the influence of the magnetic field generated by the magnet on the disk can be reduced.

According to the tenth aspect, the influence of the magnet on the disk can be further reduced. Further, according to the twelfth aspect, it is possible to reduce the influence of the magnetic material on the magnet. In the invention of claim 13, 2
Since two coils are provided and the radial driving coil is divided, the light beam passage position can be closer to the movable part, and the thickness of the optical information recording / reproducing device can be reduced as a whole. It becomes possible.

According to the nineteenth aspect of the present invention, since a metal wire or a leaf spring having a flat cross section is used as the elastic member, the access operation is performed in a state where the tracking direction matches the gravity direction. However, the position of the movable part does not displace in the tracking direction due to its own weight. Therefore, the movable range of the movable part can be set large,
It is not necessary to increase the diameter of the light beam, and as a result, the objective lens driving device and the entire optical bench can be reduced in thickness.

Further, according to the present invention, the elastic member and the holding member can be easily attached.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a first embodiment of an objective lens driving device according to the present invention.

FIG. 2 is a plan view showing a positional relationship between the objective lens driving device of FIG. 1 and a cartridge.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a diagram showing how the center of gravity is supported in the first embodiment.

FIG. 5 is a diagram showing a configuration of a modified example of the present invention.

FIG. 6 is a diagram showing a configuration of another modification of the present invention.

FIG. 7 is a diagram showing a positional relationship between a light beam and a magnetic yoke according to the first embodiment of the present invention.

FIG. 8 is a diagram showing a positional relationship between a light beam and a magnetic yoke in another modification of the present invention.

FIG. 9 is a perspective view of a main part showing an example of an elastic member of the objective lens driving device according to the first embodiment.

FIG. 10 is a perspective view showing the configuration of a second embodiment of the objective lens driving device according to the present invention.

FIG. 11 is a perspective view showing the configuration of the objective lens driving device shown in FIG. 10 in an assembled state.

FIG. 12 is a plan view showing a configuration of the objective lens driving device of FIG.

FIG. 13 is a sectional view taken along the line BB of FIG. 12;

FIG. 14 is a sectional view of an elastic member according to the second embodiment.

FIG. 15 is a sectional view of an elastic member according to the second embodiment.

FIG. 16 is a sectional view of an elastic member according to the second embodiment.

FIG. 17 is a perspective view of a main part showing a state of positioning an elastic member in the second embodiment.

FIG. 18 is a plan view showing an elastic member according to the second embodiment.

FIG. 19 is a plan view showing a state of a base in the second embodiment.

FIG. 20 is a front view showing a state of a fixing member according to the second embodiment.

FIG. 21 is a plan view of relevant parts showing a state of positioning of an elastic member in the second embodiment.

FIG. 22 is a main part plan view showing a state of positioning of an elastic member in the second embodiment.

FIG. 23 is a front view showing a configuration of a conventional objective lens driving device and a positional relationship with a cartridge.

FIG. 24 is an exploded perspective view showing a configuration of a conventional objective lens driving device.

FIG. 25 is a front view showing a configuration of a conventional objective lens driving device and a positional relationship with a cartridge.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Objective lens 2 Lens holder 3a, 3b Magnetic yoke 4a, 4b Magnet 5a, 5b Focus coil 6a, 6b Tracking coil 7a-7d Elastic member 8a-8c Printed circuit board 9 Fixing member 10 Base 11 Reflection mirror 12 Light beam 13 Optical table 14 Cartridge 14a Cartridge window 15 Disk 16 Magnetic material 17 Bent part 18 Groove part 19 Taper part 20 Guide part 21 Positioning hole 22 Stopper part 23 Space part 24 Notch 100 Adhesive receiving part F Focusing direction T Tracking direction

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroyuki Nakamura 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-6-349088 (JP, A) 149126 (JP, U) Hikaru 1-146315 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G11B ^7/ 09-7/095

Claims (34)

(57) [Claims] 1. An optical information recording / reproducing apparatus for optically writing information on or reproducing information from a disc-shaped recording medium, comprising: a base and a light beam focused on the disc-shaped recording medium; an objective lens for the optical axis is disposed perpendicular to the recording medium, the objective lens driving device for moving the objective lens in the radial direction of the direction and the recording medium of the optical axis of said light beam, said objective lens An optical member for causing a light beam passing between a driving device and the base to enter a recording medium via the objective lens, wherein the objective lens driving device has the objective lens mounted thereon, and the base has A holding means elastically held; and first and second electrokinetic conversion means for driving the holding means in a direction of an optical axis of the objective lens and in a radial direction of the recording medium. ,Previous First and second electrodynamic converter is disposed across the holding means, wherein
The first electrokinetic conversion means is the same as the second conductivity type conversion means.
And said first conductivity type conversion means is brought close to said recording medium.
An optical information recording / reproducing apparatus, wherein a light beam passes between said base and said base . 2. The apparatus according to claim 1, wherein a distance between said first electro-mechanical converter and said base is greater than a distance between said second electro-mechanical converter and said base. Optical information recording and reproducing apparatus. Wherein said first and said second electrodynamic conversion means, respectively, and the magnet, and the magnetic yoke, and a plurality of drive coils arranged in a magnetic field generated by the magnet and the magnetic yoke The optical information recording / reproducing apparatus according to claim 1, wherein the apparatus has: 4. The magnet is provided on the holding means, the magnetic yoke is fixed to the base, and the first and second electrokinetic conversion means have first and second electrokinetic conversion means. driving force, the objective lens, the holding means, and optical information recording reproducing apparatus according to claim 3, characterized in that arranged at a position which occurs symmetrically about the center of gravity of the movable portion consisting of the magnet. 5. The driving coil is provided on the holding means, the magnetic yoke is fixed to the base, and the first and second electrodynamic conversion means are provided in the first and second electrodynamic conversion means. the driving force, the objective lens, the holding means, and before
4. The optical information recording / reproducing apparatus according to claim 3, wherein the optical information recording / reproducing apparatus is disposed at a position symmetrically generated with respect to the center of gravity of the movable portion including the driving coil. 6. The objective lens driving device further includes a fixing member fixed to the base, and a plurality of elastic members for elastically supporting the holding unit, wherein the plurality of elastic members are Substantially parallel to each other, each having a first end attached to said holding means and a second end attached to said securing member,
The optical information recording / reproducing apparatus according to claim 1. 7. The plurality of elastic members include four elastic members, wherein two spring constants of the elastic members close to the recording medium are different from the other two spring constants. The optical information recording / reproducing apparatus according to claim 6, wherein: 8. The elastic member according to claim 1, wherein the first end is closer to the recording medium than the second end, and the movable coil supporting center, which is the center of the first end, is driven by the drive coil. 7. The optical information recording / reproducing apparatus according to claim 6, wherein the center of the force is coincident with the center of the force. 9. The optical system according to claim 4, wherein the magnets of the first electrokinetic conversion means and the magnets of the second electrokinetic conversion means are arranged such that different magnetic poles face each other. Information recording and playback device. Wherein said first of said length of the optical axis direction of the magnet electro-dynamic conversion means, said second electrodynamic converter of claim wherein the optical axis direction less than the length of the magnet 3 Or the optical information recording / reproducing apparatus according to 9. 11. The holding means has a magnetic member disposed between a magnet of the first electrokinetic conversion means and a magnet of the second electrokinetic conversion means. 5. The optical information recording / reproducing device according to 4. 12. The method of claim 11, wherein the holding means has an aperture for narrowing said light beam to a predetermined diameter incident on the objective lens, the aperture Claim 11 which is a part of the magnetic member Optical information recording and reproducing apparatus. Wherein said plurality of drive coils, wherein the optical axis direction driving coil for moving the objective lens in the optical axis direction, the radial direction driving coil for moving the objective lens in the radial direction The optical information recording / reproducing apparatus according to claim 3, comprising: 14. The optical information recording / reproducing apparatus according to claim 13, wherein the radial drive coil is divided in the radial direction and wound around the magnetic yoke. 15. The optical information recording / reproducing apparatus according to claim 6, wherein said fixing member and said holding means respectively have substrates for attaching said first and second ends of said plurality of elastic members. apparatus. 16. The substrate is a printed circuit board, the plurality of resilient members is a metal wire, said first and second ends of said elastic member to claim 15 which is soldered to the printed circuit board The optical information recording / reproducing apparatus according to claim 1. 17. The substrate is a metal plate, the plurality of resilient members is a metal wire, the elastic first and second end the claims are soldered to the metal plate member 15
An optical information recording / reproducing apparatus according to claim 1. 18. The optical information recording / reproducing apparatus according to claim 4, wherein said holding means has a concave portion or a convex portion for positioning said magnet on said holding means. 19. The optical information recording / reproducing apparatus according to claim 6, wherein each of the plurality of elastic members has a cross section different in thickness and width. 20. The optical information recording / reproducing apparatus according to claim 6, wherein one of the first and second ends of the plurality of elastic members is bent. 21. The optical information recording / reproducing apparatus according to claim 6, wherein the plurality of elastic members are L-shaped leaf springs. 22. The fixing member has a groove for positioning the second end of the elastic member.
22. The optical information recording / reproducing apparatus according to 0 or 21. 23. The fixing member has a substrate for mounting said second end of said elastic member, said groove is an optical information recording according to claim 22 which is provided on the substrate Playback device. 24. The optical information recording / reproducing apparatus according to claim 22, wherein a tapered portion is provided in the groove. 25. The optical information recording / reproducing apparatus according to claim 16, wherein said substrate is insert-molded on said holding means and said fixing member. 26. The fixing member has a recess for accommodating the plurality of resilient members, said recess to claim 6 viscoelastic material which is cured by irradiation with ultraviolet rays is filled The optical information recording / reproducing apparatus as described in the above. 27. The optical information recording / reproducing apparatus according to claim 26, wherein the concave portion of the fixing member is provided with a taper. 28. The optical information recording / reproducing apparatus according to claim 26, wherein a notch is provided near a portion of the base to which the fixing member is fixed. 29. The elastic member is a rod-shaped, the said holding means, substantially as described in claim 6 in which the conical bore is provided for positioning the first end of the elastic member Optical information recording and reproducing apparatus. 30. The elastic member is a rod-shaped, the fixing member is claimed in claim 6 substantially conical holes are provided for positioning said second end of said elastic member Optical information recording and reproducing apparatus. 31. The elastic member is a rod-shaped, the said holding means, said for positioning the first end of the elastic member, is provided with a substantially cylindrical bore, the bore The optical information recording / reproducing device according to claim 6, wherein each central axis forms a predetermined angle with respect to a longitudinal direction of the elastic member. Said second end of claim 32 wherein said resilient member is an optical information recording and reproducing apparatus according to claim 6 having a larger diameter than other portions of the <br/> elastic member. 33. The optical information recording / reproducing apparatus according to claim 1, wherein the material of the holding means is a liquid crystal polymer. 34. The optical information recording / reproducing apparatus according to claim 1, wherein said holding means further includes an adhesive receiving portion filled with an adhesive for bonding a side surface of said objective lens to said holding means. .