JP2003187461A - Optical pickup - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical pickup easy to adjust its optical axis without fail by using simple facilities and tools. <P>SOLUTION: The configuration of this optical pickup consists of a laser diode, a hologram laser 1 formed in one body with a hologram element and a photodiode, a collimator lens 2 to make the above laser beam parallel, a mirror 3 to change the direction of the collimated beam, a dichroic prism 4 to separate the forward beam and the backward beam, a wavelength separation filter 5 to separate the waves of a CD and a DVD, an objective lens 6 to focus the beam spot on a medium not illustrated in Fig., a laser diode 10 to emit a beam of 650 nm wavelength for the DVD, a collimator lens 9 to make the above beam parallel, a beam forming prism 8 to separate the forward beam and the backward beam of the laser diode 10, a lens 11 to focus the return beam separated by the beam forming prism 13, and a photodiode IC12 to photoelectrically convert the beam. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup, and more particularly to an optical axis adjusting mechanism for an optical pickup using a hologram laser.

[0002]

2. Description of the Related Art An optical pickup is a laser diode,
It is equipped with an optical system, an objective lens, and a photodetector, and is used for recording and reproducing information such as video, audio, or data at high density. An optical disc used as a recording medium is composed of a plastic or glass medium having a constant thickness on which light from a laser diode is incident, and a signal recording surface which is positioned on the plastic or glass medium and on which information is recorded. Also called a digital multi-function disc, the recently announced digital video disc (DVD) has a substrate thickness of 0. 0, as compared with existing CDs and CD-Rs having a substrate thickness of 1.2 mm.
It is as thin as 6 mm, but has a high recording density. An optical pickup has been proposed which can share this DVD with an existing CD. In particular, in a pickup using a hologram laser, if an offset occurs in the track error signal output from the hologram for track control, the center of the focused spot of the objective lens and the center of the track groove are deviated, causing an obstacle in track control and recording signal detection. Remarkably, the reliability is lowered. The cause of the offset in the track error signal is the tilt of the mirror, the collimator lens, and the objective lens, and the positional deviation with respect to the optical axis. These vary depending on the component accuracy and the assembly accuracy, and can be reduced to some extent by increasing the accuracy, but this causes a cost increase. In addition, it is generally practiced to compensate for the shortage by adjusting while maintaining the accuracy of the components to some extent. However, there is a problem that the equipment for adjusting the objective lens and the optical axis of the laser and the adjusting time become large, and only a trained worker can do it.

[0003]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide an optical pickup capable of easily and surely adjusting the optical axis with simple equipment and tools.

[0004]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides an optical housing for holding a hologram laser optical component in an optical pickup having a mechanism for correcting an optical axis shift of a hologram laser. When,
A holder that holds and fixes the hologram laser and a hologram laser that is held and fixed by the holder are provided, and the holder moves in the X-axis, Y-axis, and Z-axis directions with respect to the optical housing and the X-axis and Y-axis. It is characterized in that it can be moved in a rotation angle direction around the axis and the Z axis. The hologram laser refers to a device in which a laser diode, a hologram element, and a photodiode are integrally formed and packaged. The principle of this device is that a laser spot emitted from a laser diode irradiates a CD pit, and the reflected light is deflected by a hologram element and detected by a photodiode. If an offset occurs in the track error signal output during tracking control in this hologram laser, the center of the focused spot of the objective lens and the track groove will be displaced, and the track control and recording signal detection will be hindered, significantly reducing the reliability. Will end up. The main cause of this is a positional shift of the laser spot with respect to the optical axis. This misalignment varies depending on the component accuracy and the assembly accuracy, and can be reduced to some extent if the accuracy is increased, but it causes a cost increase. Therefore, it is preferable to prepare in advance a jig capable of adjusting the optical axis when the hologram laser is assembled to the optical housing. As this jig, a hologram laser is clamped, and the X-axis, Y-axis, and
A clamper having a function of moving in the Z-axis direction and moving in the rotation angle direction around the X-axis, Y-axis, and Z-axis is effective. According to this invention, the holder can be moved in the X-axis, Y-axis, and Z-axis directions with respect to the optical housing and can be moved in the rotation angle direction around the X-axis, Y-axis, and Z-axis. This makes it possible to adjust the optical axis easily and reliably with simple equipment and tools.

According to a second aspect of the present invention, the holder is integrally formed with a heat sink that radiates heat generated from the hologram laser. The holder and the hologram laser must be fixed integrally. Further, heat is generated from the hologram laser, and if the heat exceeds a predetermined temperature, the reliability of the device may be impaired. Therefore, by making the holder itself a heat sink having a heat radiating function, the role of the holder and the role of heat radiation can be fulfilled at the same time. According to this technical means, since the holder is integrally formed with the heat sink that radiates the heat generated from the hologram laser, the number of parts can be reduced and the heat radiation effect can be enhanced. According to a third aspect of the present invention, it is an effective means of the present invention that the holder is adhered to the optical housing with an ultraviolet curing resin after the adjustment of the holder. After adjusting the optical axis of the hologram laser, it is necessary to fix it in that state. If mechanically fixed with screws or the like, the stress may cause distortion and the adjustment position may be displaced. Therefore, as a method of fixing without applying mechanical stress, an air bonding method in which a gap is provided between the housing and the holder and the gap is filled with an adhesive is preferable. However, the problem with adhesives is that it takes time to solidify. As a means for solving this, there is an ultraviolet curable resin. This is because the resin cures when it is exposed to UV light.
The curing time is about tens of seconds, which is significantly faster than that of general adhesives. According to such technical means,
Since the holder is adhered to the optical housing with the ultraviolet curable resin, the adjustment position does not shift due to stress, and the adhesion time can be shortened.

According to a fourth aspect of the present invention, in an optical pickup having a mechanism for correcting the optical axis shift of the hologram laser, an optical housing for holding the hologram laser optical component, and a first holder having an opening at the approximate center of the concave spherical surface. , The first
A second holder having an opening at approximately the center of a convex spherical surface that fits with the holder, and a hologram laser fixed to the second holder, wherein the first holder is X-shaped relative to the optical housing. The second holder is movable relative to the optical housing in the X-axis and Y-axis directions.
It is characterized in that it can be moved in a rotation angle direction around the axis and the Z axis. In the case of the air bonding of claim 1, it is necessary to provide a gap for adjustment between the optical housing and the holder. Therefore, after the adjustment, the gap had to be filled in some way. Therefore, a first holder that can move the holder in the X-axis and Y-axis directions with respect to the optical housing and a second holder that can move in the rotation angle direction around the X-axis, Y-axis, and Z-axis are provided. A method is considered in which they are separated and the adhesion in the air is eliminated. According to this method, first, the first holder and the second holder are temporarily fixed and the X-axis and Y-axis are fixed.
Complete the axial adjustment, then use the second holder to
Adjust the rotation angle direction around the axis, Y axis, Z axis,
Then fix it. Here, the shapes of the first and second holders are preferably such that they can fit in each other and move in three directions. According to this invention, the first holder having the opening at the approximate center of the concave spherical surface, the second holder having the opening at the approximate center of the convex spherical surface fitted with the first holder, and the second holder And a hologram laser fixed to the holder of the first housing, wherein the first holder has an X-axis and a Y-axis with respect to the optical housing.
The second holder is movable in the axial direction, and the second holder is movable in the rotation angle direction around the X axis, the Y axis, and the Z axis with respect to the optical housing. The gap can be eliminated.
According to a fifth aspect, after the adjustment of the first and second holders, the first holder is adjusted.
It is also an effective means of the present invention that the holder is adhered to the optical housing with an ultraviolet curable resin and the second holder is adhered to the first holder with an ultraviolet curable resin. Since the first holder and the second holder are individually adjusted and fixed, if it becomes necessary to readjust them later, one of the adhesives is removed and only that portion is removed. It can be completed if readjusted. According to this technical means, the first holder is adhered to the optical housing with the ultraviolet curable resin, and the second holder is adhered to the first holder with the ultraviolet curable resin. Can be reduced.

According to a sixth aspect of the present invention, in an optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, an optical housing holding a hologram laser optical component and a stem portion forming a structure of the hologram laser are the same or the same. A holder having an opening at substantially the center of a concave spherical surface having a larger diameter than the stem portion and a hologram laser having the stem portion are provided, and the holder moves in the X-axis and Y-axis directions with respect to the optical housing. The stem portion is movable with respect to the holder in a rotation angle direction around the X axis, the Y axis, and the Z axis. According to the fourth aspect, the first holder and the second holder are brought into close contact with each other to eliminate the gap by air bonding, but the cost is increased because two holders are required. Therefore,
It is conceivable to reduce the number of holders by using the stem portion, which is the structure of the hologram laser, instead of the holders. According to such an invention, a holder having an opening substantially at the center of a concave spherical surface having a diameter equal to or larger than the stem portion forming the structure of the hologram laser,
A hologram laser having the stem portion, wherein the holder is movable in the X-axis and Y-axis directions with respect to the optical housing, and the stem portion is relative to the holder in the X-axis, Y-axis and Z-axis. Since it is movable in the rotation angle direction around the axis, the number of parts can be reduced and the cost can be reduced. According to a seventh aspect of the present invention, after adjusting the holder and the stem portion, the holder is adhered to the optical housing with an ultraviolet curable resin, and the stem portion is adhered to the holder with an ultraviolet curable resin. is there. According to this technical means, the same operational effect as that of claim 5 is achieved. According to claim 8 in an optical pickup having a mechanism for correcting an optical axis shift of a hologram laser,
An optical housing for holding a hologram laser optical component, and a hologram laser having a stem portion forming a structure of the hologram laser are provided, and an opening of an optical path entrance of the optical housing is formed into a concave spherical surface, and the opening is formed. On the other hand, it is characterized in that the stem portion is movable in a rotation angle direction around the X axis, the Y axis, and the Z axis. Claim 6
Then, I reduced the number of holders by one to reduce the cost, but X
When the adjustment in the axis and Y-axis directions is not necessary, the opening of the optical path entrance of the optical housing is formed into a concave spherical surface to serve as one holder, and the stem portion is closely attached to the holder. It can be adjusted in the rotation angle direction about the X axis, the Y axis, and the Z axis. According to this invention, the opening portion of the optical path entrance of the optical housing is formed in a concave spherical shape, and the stem portion is moved with respect to the opening portion in the rotational angle direction about the X axis, the Y axis, and the Z axis. By making it possible, the number of parts can be further reduced.

According to a ninth aspect of the present invention, it is an effective means of the present invention that after the adjustment of the stem portion, the stem portion is adhered to the opening portion of the optical housing with an ultraviolet curable resin. According to such a technical means, the stem portion is bonded to the opening of the optical housing by the ultraviolet curable resin,
There is no adjustment position shift due to stress, and the bonding time can be shortened. According to a tenth aspect of the present invention, in an optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, an optical housing holding a hologram laser optical component, a holder having a hole for an adjustment pin for adjusting the inclination of the hologram laser, A hologram laser fixed to the holder, wherein the holder is movable in a rotation angle direction around the X-axis, Y-axis, and Z-axis with respect to the optical housing, and after the movement, the ultraviolet-curing resin is used to The holder is bonded to the optical housing. If holes having the same spacing as the adjustment pins are formed in the holder in advance, the adjustment pins can be inserted into the holes for adjustment. The angle in the X-axis direction can be adjusted by tilting the adjustment pin back and forth, the angle in the Y-axis direction can be adjusted by tilting it left and right, and the angle in the Z-axis direction can be adjusted by rotating it. After that, it is bonded and fixed in that state. According to this invention, an optical housing for holding the hologram laser optical component, a holder having an adjustment pin hole for adjusting the inclination of the hologram laser, and a hologram laser fixed to the holder are provided, and the holder is With a simple jig, the optical housing can be moved in a rotation angle direction around the X axis, the Y axis, and the Z axis, and after the movement, the holder is bonded to the optical housing with an ultraviolet curable resin. The angle can be easily adjusted.

According to a tenth aspect of the present invention, in an optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, an optical housing for holding a hologram laser optical component,
A third holder having a movable structure with respect to the optical housing and having an opening at substantially the center; a fourth holder fixed to the third holder and having a U-shaped elastic structure; And a hologram laser fixed to the holder of
Holder allows movement in the X-axis and Y-axis directions with respect to the optical housing, and the fourth holder rotates about the X-axis, Y-axis, and Z-axis with respect to the third holder. It is characterized by being movable in the angular direction. The method of adjusting the rotation angle direction is generally a method using a jig, but there is also a method of simply adjusting without using a jig. That is a method in which a hologram laser is fixed to a spring-shaped member and stress is applied to the spring by a screw to incline it. This method is effective as a rough adjustment as a step before the final adjustment. According to this invention, the third holder having a movable structure with respect to the optical housing and having an opening at substantially the center, and the fourth holder fixed to the third holder and having a U-shaped elastic structure And a hologram laser fixed to the fourth holder,
The third holder has an X axis with respect to the optical housing,
Since it is possible to move in the Y-axis direction and the fourth holder can move in the rotational angle direction around the X-axis, Y-axis, and Z-axis with respect to the third holder, a simple structure is provided. Allows coarse adjustment in the direction of the rotation axis, shortening the total adjustment time.

According to a twelfth aspect of the present invention, in an optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, an optical housing for holding a hologram laser optical component,
A fifth holder in which a part of the housing is formed in a shape having a U-shaped elastic structure and a hologram laser fixed to the fifth holder are provided, and the fifth holder is provided with respect to the optical housing. It is characterized in that it is movable in a rotation angle direction around the X axis, the Y axis and the Z axis. The optical housing is generally made of resin. Therefore, a U-shaped holder is formed in advance at the stage of manufacturing the mold, and the elasticity of the resin can be used to adjust the rotation angle direction. However, in this case, adjustment in the X-axis and Y-axis directions is impossible.
According to this invention, the housing includes a fifth holder in which a part of the housing has a U-shaped elastic structure, and a hologram laser fixed to the fifth holder. X-axis, Y-axis with respect to the optical housing,
The number of parts can be minimized by being movable in the rotation angle direction around the Z axis.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the embodiments shown in the drawings. However, the constituent elements, types, combinations, shapes, relative arrangements, and the like described in this embodiment are merely explanatory examples, not the gist of limiting the scope of the present invention thereto, unless specifically stated. .. FIG. 1 is a schematic configuration diagram of an optical pickup using a hologram laser according to an embodiment of the present invention. This configuration has a hologram laser 1 in which a laser diode, a hologram element, a photodiode, etc. are integrally formed, a collimating lens 2 for collimating the beam spot of the hologram laser 2, a mirror 3 for bending the collimated beam, and a forward path and a backward path. Dichroic prism 4 for separating beams
And a wavelength selection filter 5 for separating the wavelengths of CD and DVD
An objective lens 6 that focuses a beam spot on a medium (not shown), a DVD laser diode 10 that emits a laser beam of 650 nm wavelength for DVD, a collimator lens 9 that makes the beam parallel light, and a DVD. A beam shaping prism 8 for separating the forward and backward beams from the laser diode 10; a lens 11 for focusing the backward beam separated by the beam shaping prism 13;
It is composed of a photodiode IC12 that photoelectrically converts the beam. In addition, the hologram laser 1 is 7 for a CD.
It is a laser with a wavelength of 80 nm.

Next, the general operation of this optical pickup will be described. For example, when reading data on a CD, an operation called focusing for focusing a laser spot on a recording medium and tracking for moving the spot to a track position are performed. Although there are various types of these methods, detailed description thereof will be omitted in the present invention. In the case of the focusing and tracking operations, the hologram laser 1
A laser beam having a wavelength of 780 nm is emitted from the laser diode therein. The laser beam is collimated by the collimator lens 2 and is bent at a right angle by the mirror 3. The mirror 3 may not be necessary depending on the configuration of the optical system. The bent beam passes through the dichroic prism 4, the wavelength selection filter 5 removes unnecessary wavelengths, and the objective lens 6 irradiates the CD with a beam spot. The reflected light from the CD passes through the same optical axis and returns in the order of the objective lens 6, the wavelength selection filter 5, the dichroic prism 4, the mirror 3, the collimator lens 2, and the hologram laser 1. There is a hologram element (not shown) in the hologram laser 1, and the hologram element is deflected by the hologram element 1 to be separated from the emission beam and detected by a photodiode (not shown). Here, if the beam is not focused, the beam detected by the photodiode becomes large. Therefore, although not shown, an actuator that moves the objective lens 6 in the thickness direction of the CD causes the beam detected by the photodiode to be a predetermined beam. Controlled until size.
This series of operations is similarly performed in tracking control.

In the case of a DVD, the DVD laser diode 10 emits a beam having a wavelength of 650 nm.
The laser beam is collimated by a collimator lens 9, obliquely enters a beam shaping prism 8, passes through a prism 13 and is bent at a right angle by a dichroic prism 4, and an unnecessary wavelength is removed by a wavelength selection filter 5, and an objective lens. At 6, the beam spot is applied to the DVD. The reflected light from the DVD passes through the same optical axis and reaches the objective lens 6, the wavelength selection filter 5, the dichroic prism 4 and the prism 13, is bent at a right angle by the prism 13 and is focused by the lens 11, and the photodiode I
It is detected by C12. As described above, the hologram laser means a device in which a laser diode, a hologram element, and a photodiode are integrally formed and packaged. According to this principle, a laser spot emitted from a laser diode irradiates a pit of a CD, and the reflected light is deflected by a hologram element and detected by a photodiode. If an offset occurs in the track error signal output during tracking control in this hologram laser, the center of the focused spot of the objective lens and the track groove will be displaced, and the track control and recording signal detection will be hindered, significantly reducing the reliability. Will end up.
The main cause of this is a positional shift of the laser spot with respect to the optical axis. This misalignment varies depending on the component accuracy and the assembly accuracy, and can be reduced to some extent if the accuracy is increased, but it causes a cost increase. Therefore, it is preferable to prepare in advance a jig capable of adjusting the optical axis when the hologram laser is assembled to the optical housing.

FIG. 2 is a perspective view of an optical pickup and a jig according to the first embodiment of the present invention. This is a holder 16 formed integrally with the heat sink in the optical housing 15.
When installing. The hologram laser 24 is previously fixed to the holder 16. First, the protrusion 18 of the clamper 22 is aligned with the recess 17 of the holder 16, and the pin 19 is tightened to clamp the holder 16. In that state, the X, Y, and Z axis directions are adjusted by observing the waveform by an adjusting jig (not shown). Next, the rotation directions of the X, Y, and Z axes are adjusted to adjust the respective angles. During this adjustment, the housing 15 and the adjustment jig are firmly fixed. In addition, a slight gap is provided between the housing 15 and the holder 16 for adjustment. Then, after the adjustment is completed, an ultraviolet effect resin is filled in the gap and ultraviolet rays are applied to cure the resin (in-air adhesion). After confirming the hardening, the jig is removed from the holder to complete. As described above, the hologram jig is clamped as the adjustment jig, and the X axis and Y
A clamper having a function of moving in the directions of the axis and the Z axis and moving in the direction of the rotation angle around the X axis, the Y axis, and the Z axis is effective. In addition, the holder 16 and the hologram laser 24
Must be fixed together. Further, heat is generated from the hologram laser 24, and if the heat exceeds a predetermined temperature, the reliability of the device may be impaired. Therefore, by making the holder 16 itself a heat sink having a heat radiating function, the role of the holder and the role of heat radiation can be fulfilled at the same time. As a result, the number of parts can be reduced and the heat radiation effect can be enhanced. Further, after adjusting the optical axis of the hologram laser 24, it is necessary to fix it in that state. If mechanically fixed with screws or the like, the stress may cause distortion and the adjustment position may be displaced. Therefore, as a method of fixing without applying mechanical stress, an air bonding method in which a gap is provided between the housing 15 and the holder 16 and the gap is filled with an adhesive is preferable. However, the problem with adhesives is that it takes time to solidify. As a means for solving this, there is an ultraviolet curable resin. This is because the resin cures when it is irradiated with ultraviolet rays, and the curing time is several tens of seconds, which is much faster than ordinary adhesives, so there is no misalignment due to stress, and the adhesive time Can be shortened.

FIG. 3 is a view showing a holder portion of an optical pickup according to the second embodiment of the present invention. (A) is a perspective view, (b) is a side sectional view. This is done in order to eliminate the gap with the housing due to air adhesion in FIG.
It is an embodiment in which the gap between the holder and the housing is eliminated by the type of holder. In the holder 30, a concave spherical surface is formed at the opening of the optical path, and the convex spherical holder 3 is fitted completely with the concave spherical surface.
The hologram laser 32 is fixed to the holder 31 in advance. As shown in FIG. 3B, the holder 30 and the holder 31 are temporarily fixed to the housing 34. This temporary fixing method is performed by a jig not shown. In that state, first, the X and Y axis directions are adjusted, and only the holder 30 is fixed with an adhesive. Next, the holder 31 is adjusted in the rotational directions of the X, Y, and Z axes to adjust the respective angles. Then, the holder 31 is fixed to the holder 30 with an adhesive. As mentioned above,
In the case of the air-bonding in FIG. 2, it was necessary to provide a gap for adjustment between the optical housing and the holder. Therefore, after the adjustment, the gap had to be filled in some way. Therefore, the holder 30 that can move the holder in the X-axis and Y-axis directions with respect to the optical housing, the X-axis,
A method may be considered in which the air-bonding is eliminated by separating the Y-axis and the holder 31 that can move in the rotation angle direction around the Z-axis. According to this method, first, the holder 30 and the holder 3
1 is temporarily fixed to complete the adjustment in the X-axis and Y-axis directions, then the holder 31 is used to adjust the rotation angle direction around the X-axis, Y-axis, and Z-axis, and then fixed. To do. Here, the shapes of the holder 30 and the holder 31 are preferably such that they can fit in each other and can move in three directions. This makes it possible to eliminate the gap between the optical housing and the hologram laser. Further, since the holder 30 and the holder 31 are individually adjusted and fixed, if it is necessary to readjust afterwards, either one of the adhesives should be removed and only that portion should be readjusted. Can be completed. This can reduce the trouble of readjustment.

FIG. 4 is a view showing a holder portion of an optical pickup according to the third embodiment of the present invention. This is X,
A holder 35 made of a spring material is fixed on a holder 36 for adjusting the Y-axis direction, and a hologram laser 38 is fixed to the holder in advance. Further, the holder 35 is fixed at three places by screws 37, and the rotating directions of the X, Y, and Z axes can be adjusted by individually moving these screws. FIG. 5 is a diagram showing a holder portion of an optical pickup according to the fourth embodiment of the present invention. This is provided with a convex spherical holder 41 which forms a concave spherical surface in the opening of the holder 40 and which fits perfectly with the concave spherical surface.
The hologram laser 43 is fixed in advance. Further, there are screws 42, 44, 45 at three locations, and by individually moving each screw, the rotation directions of the X, Y, and Z axes can be adjusted. FIG. 6 is a diagram showing a holder portion of an optical pickup according to the fifth embodiment of the present invention. (A) is a perspective view, (b) is a side sectional view.
This has a structure in which a concave spherical surface is formed in the holder 51 at the opening of the optical path, and the X and Y axis directions can be adjusted. The configuration is such that the stem portion 53 of the hologram laser is brought into close contact with the concave spherical surface. As for the adjustment method, as shown in FIG. 6B, the holder 51 and the stem portion 53 are temporarily fixed to the housing 50. This temporary fixing method is performed by a jig not shown.
In that state, first, the holder 51 is moved to adjust the X and Y axis directions, and only the holder 51 is fixed with an adhesive. Next, the stem portion 53 is adjusted in the rotation directions of the X, Y, and Z axes to adjust the respective angles. Then, the stem portion 53 is attached to the holder 5
Fix to 1 with adhesive. As described above, although the holder 30 and the holder 31 are brought into close contact with each other in FIG. 3 to eliminate the gap due to the air bonding, the cost is increased because two holders are required. Therefore, it is conceivable to reduce the number of holders by using the stem portion 53, which is the structure of the hologram laser, instead of the holders. As a result, the number of parts can be reduced and the cost can be reduced. Also,

FIG. 7 is a view showing a holder portion of an optical pickup according to the sixth embodiment of the present invention. (A) is a perspective view, (b) is a side sectional view. This is a configuration in which a concave spherical surface is formed in the opening of the optical path in the housing 60, and the stem portion 62 of the hologram laser is brought into close contact with the concave spherical surface. As for the adjusting method, as shown in FIG. 7B, the stem portion 62 is temporarily fixed to the housing 60. This temporary fixing method is performed by a jig not shown. In that state, first, the stem portion 62 is adjusted in the rotational directions of the X, Y, and Z axes to adjust the respective angles. Then, the stem portion 62 is fixed to the housing 60 with an adhesive. As described above, in FIG. 6, the number of holders is reduced by one to reduce the cost. However, when the adjustment in the X-axis and Y-axis directions is not necessary, the opening of the optical path entrance of the optical housing has a concave spherical surface. By forming it as one holder, the stem portion can be brought into close contact therewith and adjusted in the rotational angle direction around the X-axis, Y-axis, and Z-axis. Can be reduced.
FIG. 8 is a diagram showing a holder portion of the optical pickup according to the seventh embodiment of the present invention. (A) is a perspective view,
(B) is a perspective view using the adjustment pin. This is a holder 72 with holes 74 spaced between the adjustment pins.
In addition, the hologram laser 73 is fixed in advance. The adjustment method is as shown in FIG.
By inserting the adjusting pin 75 into 4 and rotating the shaft 76, the rotation directions of the X, Y, and Z axes are adjusted to adjust the respective angles. Then, the adjustment pin is removed and fixed to the recesses on both sides of the holder 72 with the adhesive 77. As described above, if holes having the same spacing as the adjustment pins are made in the holder in advance, the adjustment pins can be inserted into the holes for adjustment. The angle in the X-axis direction can be adjusted by tilting the adjustment pin back and forth, the angle in the Y-axis direction can be adjusted by tilting it left and right, and the angle in the Z-axis direction can be adjusted by rotating it. After that, it is bonded and fixed in that state. Thereby, the angle can be easily adjusted with a simple jig.

FIG. 9 is a view showing a holder portion of an optical pickup according to the eighth embodiment of the present invention. This is a structure in which a U-shaped holder 86 made of an elastic material is fixed to the holder 85, and the hologram laser 89 is previously fixed thereto. In this adjusting method, it is possible to adjust the amount of deflection in a hole formed in two places of the holder 86 with a screw, and then rotate the screw 87 to adjust the rotation directions of the X, Y, and Z axes. As described above, the method of adjusting the rotation angle direction is generally a method using a jig, but there is also a method of simply adjusting without using a jig. That is a method in which a hologram laser is fixed to a spring-shaped member and stress is applied to the spring by a screw to incline it. This method is effective as a rough adjustment as a step before the final adjustment. This makes it possible to perform coarse adjustment in the direction of the rotation axis with a simple structure,
The total adjustment time can be shortened. Figure 10
FIG. 13 is a diagram showing a holder portion of an optical pickup according to a ninth embodiment of the present invention. This is provided with a holder part 91 formed integrally with a part of the housing 90, and the holder part 91
Part of this is to utilize the elasticity of the resin. When adjusting, the rotation directions of the X, Y, and Z axes can be adjusted with the screw 92 in the hole formed in the holder portion 91. As described above, the optical housing is generally made of resin. Therefore, the U-shaped holder can be formed in advance at the stage of manufacturing the mold, and the elasticity of the resin can be used to adjust the rotation angle direction. However, in this case, adjustment in the X-axis and Y-axis directions is impossible. Thereby, the number of parts for adjustment can be minimized.

[0019]

As described above, according to the present invention, in claim 1, the holder is attached to the optical housing in an X direction.
By the movement in the axis, Y-axis, and Z-axis directions and the movement in the rotation angle direction around the X-axis, Y-axis, and Z-axis,
The optical axis can be adjusted easily and reliably with simple equipment and tools. According to the second aspect, since the holder is integrally formed with the heat sink that radiates the heat generated from the hologram laser, the number of parts can be reduced and the heat radiation effect can be enhanced. According to the third aspect, since the holder is bonded to the optical housing with the ultraviolet curable resin, there is no adjustment position shift due to stress, and the bonding time can be shortened. According to a fourth aspect of the present invention, there is provided a first holder having an opening at substantially the center of the concave spherical surface, a second holder having an opening at the substantially center of the convex spherical surface fitted with the first holder, and the second holder. And a hologram laser fixed to the holder, the first holder is movable in the X-axis and Y-axis directions with respect to the optical housing, and the second holder is with respect to the optical housing. Since it is movable in the rotation angle direction around the X axis, the Y axis, and the Z axis, the gap between the optical housing and the hologram laser can be eliminated. According to a fifth aspect of the present invention, the first holder is adhered to the optical housing with an ultraviolet curable resin, and the second holder is adhered to the first holder with an ultraviolet curable resin. can do. According to a sixth aspect of the present invention, there is provided a holder having an opening portion substantially at the center of a concave spherical surface having a diameter equal to or larger than the stem portion forming the structure of the hologram laser, and a hologram laser having the stem portion. The holder is capable of moving in the X-axis and Y-axis directions with respect to the optical housing, and the hologram laser is in a rotation angle direction around the X-axis, Y-axis, and Z-axis with respect to the holder. Since it is movable, the number of parts can be reduced and the cost can be reduced. Further, the seventh aspect has the same effect as the fifth aspect.

According to another aspect of the present invention, the opening portion of the optical path entrance of the optical housing is formed in a concave spherical shape, and the stem portion is rotated about the X-axis, Y-axis, and Z-axis with respect to the opening portion. The number of parts can be further reduced by making it movable in the direction. According to the ninth aspect, since the stem portion is adhered to the opening of the optical housing by the ultraviolet curable resin, there is no displacement of the adjustment position due to the stress and the adhering time can be shortened. According to a tenth aspect of the invention, an optical housing for holding a hologram laser optical component, a holder having a hole for an adjustment pin for adjusting the inclination of the hologram laser, and a hologram laser fixed to the holder are provided, and the holder is provided. With a simple jig, the optical housing can be moved in a rotation angle direction around the X axis, the Y axis, and the Z axis, and after the movement, the holder is bonded to the optical housing with an ultraviolet curable resin. The angle can be easily adjusted. In addition, claim 11
A third holder having a movable structure with respect to the optical housing and having an opening at substantially the center, and U fixed to the third holder.
A fourth holder having a V-shaped elastic structure and a hologram laser fixed to the fourth holder are provided, and the third holder moves in the X-axis and Y-axis directions with respect to the optical housing. Since the fourth holder can move in the rotation angle direction around the X axis, the Y axis, and the Z axis with respect to the third holder, the coarse adjustment in the rotation axis direction can be performed with a simple structure. It is possible to shorten the total adjustment time. A twelfth aspect of the present invention is a fifth holder in which a part of the housing is formed in a shape having a U-shaped elastic structure,
A hologram laser fixed to the fifth holder, wherein the fifth holder is X-axis relative to the optical housing.
The number of parts can be minimized by making it movable in the rotation angle direction around the axis, the Y axis, and the Z axis.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an optical pickup using a hologram laser according to an embodiment of the present invention.

FIG. 2 is a perspective view of an optical pickup and a jig according to the first embodiment of the present invention.

3A and 3B are diagrams showing a holder portion of an optical pickup according to a second embodiment of the present invention, FIG. 3A being a perspective view and FIG.
FIG.

FIG. 4 is a diagram showing a holder portion of an optical pickup according to a third embodiment of the present invention.

FIG. 5 is a diagram showing a holder portion of an optical pickup according to a fourth embodiment of the present invention.

6A and 6B are views showing a holder portion of an optical pickup according to a fifth embodiment of the present invention, in which FIG. 6A is a perspective view and FIG.
FIG.

7A and 7B are views showing a holder portion of an optical pickup according to a sixth embodiment of the present invention, in which FIG. 7A is a perspective view and FIG.
FIG.

8A and 8B are views showing a holder portion of an optical pickup according to a seventh embodiment of the present invention, in which FIG. 8A is a perspective view and FIG.
FIG. 6 is a perspective view using an adjustment pin.

FIG. 9 is a diagram showing a holder portion of an optical pickup according to an eighth embodiment of the present invention.

FIG. 10 is a diagram showing a holder portion of an optical pickup according to a ninth embodiment of the present invention.

[Explanation of symbols]

1 hologram laser, 2 collimator lens, 3 mirror, 4 dichroic prism, 5 wavelength selection filter, 6 objective lens

Claims (12)

[Claims] 1. An optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, an optical housing holding a hologram laser optical component, a holder holding and fixing the hologram laser, and a hologram held and fixed by the holder. A laser, wherein the holder has an X-axis, a Y-axis with respect to the optical housing,
An optical pickup characterized by being movable in a Z-axis direction and movable in a rotation angle direction around the X-axis, Y-axis and Z-axis. 2. The optical pickup according to claim 1, wherein the holder is integrally formed with a heat sink that radiates heat generated from the hologram laser. 3. The optical pickup according to claim 1, wherein after the position of the holder is adjusted, the holder is adhered to the optical housing with an ultraviolet curable resin. 4. An optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, an optical housing for holding a hologram laser optical component, a first holder having an opening at substantially the center of a concave spherical surface, A second holder having an opening at substantially the center of a convex spherical surface that fits with the first holder; and a hologram laser fixed to the second holder, the first holder being relative to the optical housing. X axis,
An optical pickup which is movable in the Y-axis direction and is movable in a rotation angle direction around the X-axis, the Y-axis, and the Z-axis with respect to the optical housing. . 5. After adjusting the positions of the first and second holders,
The optical pickup according to claim 4, wherein the first holder is adhered to the optical housing with an ultraviolet curable resin, and the second holder is adhered to the first holder with an ultraviolet curable resin. 6. An optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, wherein an optical housing holding a hologram laser optical component and a stem portion forming a structure of the hologram laser are equal to or more than the stem portion. A concave laser having a large diameter is provided with a holder having an opening at substantially the center thereof, and a hologram laser having the stem portion, and the holder is movable in the X-axis and Y-axis directions with respect to the optical housing. An optical pickup, wherein the stem portion is movable with respect to the holder in a rotation angle direction around the X axis, the Y axis, and the Z axis. 7. The holder is adhered to the optical housing with an ultraviolet curable resin after the position adjustment of the holder and the stem portion, and the stem part is adhered to the holder with an ultraviolet curable resin. The optical pickup according to item 6. 8. An optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, comprising: an optical housing holding a hologram laser optical component; and a hologram laser having a stem portion forming a structure of the hologram laser. An opening at the optical path entrance of the optical housing is formed in a concave spherical shape, and the stem portion is provided with respect to the opening in the X axis, Y axis, and Z
An optical pickup characterized by being movable in a rotation angle direction around an axis. 9. The optical pickup according to claim 8, wherein after the position of the stem portion is adjusted, the stem portion is adhered to the opening of the optical housing with an ultraviolet curable resin. 10. An optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, an optical housing for holding a hologram laser optical component, and a holder having a hole for an adjusting pin for adjusting the inclination of the hologram laser. A hologram laser fixed to the holder, wherein the holder is an X-axis, a Y-axis with respect to the optical housing,
An optical pickup characterized in that it is movable in a rotation angle direction around the Z axis, and after the movement, the holder is bonded to the optical housing with an ultraviolet curable resin. 11. An optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, comprising an optical housing for holding a hologram laser optical component, a movable structure with respect to the optical housing, and an opening at substantially the center. A third holder, a fourth holder fixed to the third holder and having a U-shaped elastic structure, and a hologram laser fixed to the fourth holder, wherein the third holder is X axis with respect to the optical housing,
The fourth holder is movable in the Y-axis direction, and the fourth holder is movable with respect to the third holder in a rotation angle direction around the X-axis, the Y-axis, and the Z-axis. Optical pickup. 12. An optical pickup having a mechanism for correcting an optical axis shift of a hologram laser, wherein an optical housing holding a hologram laser optical component and a part of the housing are formed in a shape having a U-shaped elastic structure. A fifth holder and a hologram laser fixed to the fifth holder are provided, and the fifth holder has an X axis with respect to the optical housing,
An optical pickup characterized by being movable in a rotation angle direction around the Y axis and the Z axis.