JP2003151170A - Optical integrated unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To offer the constitution of a hologram laser unit and the arrangement of optical elements and to obtain an optical integrated unit which is small-size, lightweight and excellent in the environmental resistance and which can be easily assembled as an optical pickup. SOLUTION: The optical integrated unit comprises a light emitting element 26 to emit a beam to irradiate an optical disk, a light receiving element 20 to receive the beam of the light emitting element 26 reflected on the optical disk, a hologram element 22 to diffract the reflected beam from the optical disk, and a collimator lens 12 to receive the beam of the light emitting element 26 transmitting through the hologram element 22. The unit is equipped with the light emitting element 26, light receiving element 20, hologram element 22 and collimator lens 12 as an integrated device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk used for recording / reproducing information signals to / from an optical disk such as a compact disk (CD), a mini disk (MD), a digital versatile disk (DVD) and a magneto-optical disk (MO). The present invention relates to pickup technology, and more particularly to the optical integrated unit thereof.

[0002]

2. Description of the Related Art An optical pickup device records and reproduces information on and from a disc as a recording medium, and includes a light source, an objective lens for focusing a light beam from the light source on the disc, and reflected light from the disc. A light receiving element for detecting
It consists of a hologram element and various other optical components provided in the optical path from the light source to the disc. It has already been performed to package or unitize the optical components, particularly the light emitting element, the hologram element, and the light receiving element, which constitute the optical pickup device. By doing so, the hologram laser unit can be configured and handled as one component by performing assembly and adjustment in advance, so that it is possible to obtain an optical pickup device that is easy to assemble and adjust and is small in size and excellent in environmental resistance. The technical development of such an optical pickup device initially started with a pickup for a CD, particularly for a pickup for reproduction, followed by a development for a recording pickup for a CD and a pickup for a DVD reproduction, and so on. There is.

In order to reduce the size and weight of an optical pickup, it has been proposed to integrate a tracking beam generating function, an optical branching function, and an error signal generating function, which are conventionally composed of a plurality of optical components, into one hologram element. ing. Then, the semiconductor laser (laser diode) as the light emitting element and the photodiode as the light receiving element are arranged in one package, and the optical arrangement is such that the influence of the wavelength fluctuation of the laser diode can be completely compensated. As a result, compact and lightweight optical pickups with excellent environmental resistance have been developed. Sharp Technical Report (19
The holographic pickup for CD using the three-beam method described in No. 42 of 1989) is an example, and it has been confirmed to have excellent performance as an optical pickup for CD.

Certainly, the optical pickup using the hologram laser unit as described above is smaller in size, lighter in weight, superior in environmental resistance, and easier to assemble and adjust as compared with the optical pickup not using the hologram laser unit. There is an advantage. However, in recent years, with the progress of development of a hologram laser unit for an optical pickup which is compatible with a DVD recording system and a medium having a higher recording density than that,
Multi-functionalization, high accuracy of assembly adjustment, further miniaturization,
The requirements for weight reduction and environmental resistance are becoming strict, and the configuration of the conventional hologram laser unit is insufficient to satisfy the above requirements.

For example, there is a problem of relative distance between the light emitting element and the collimator lens. At present, there is no light emitting element that can obtain a sufficient output as a light source of a pickup for recording system of DVD media. Therefore, a pickup optical system for performing beam shaping has been proposed and put into practical use in order to compensate for insufficient output of the light emitting element. The optical system of the optical pickup having the beam shaping means is required to have higher accuracy in the relative distance between the light emitting element and the collimator lens than the optical system which does not need the beam shaping means.

In such a case, even if the conventional hologram laser unit is used, a highly accurate adjusting and assembling step of the light emitting element and the collimator lens is required at the time of assembling the optical pickup, and this portion is packaged. Since it has not been made into a product, there is still a problem in environmental resistance. After all, it is considered that the original meaning or effect of the hologram laser unit will be secured by packaging an optical element that requires highly accurate adjustment and assembly as one component and putting it in the assembly process of the optical pickup.

FIG. 15 shows a configuration example of a conventional optical pickup. 15A shows an example in which the optical integrated unit is not used, FIG. 15B shows an example in which the optical integrated unit is used, and FIG. 15C shows an example in the optical integrated unit. Figure 15
In (a), the light beam emitted from the semiconductor laser 10 as a light emitting element passes through the grid 11 and is made into a parallel light beam or a substantially parallel light beam by the collimator lens 12, and the beam shape is shaped by the beam shaping prism 13, and the polarization beam splitter is used. 14 reflects upwards in the figure. The reflected light passes through the quarter-wave plate 15 and the aperture limiting filter 16, is focused as a light spot on the recording surface of the optical disc 18 by the objective lens 17, and is reflected by the recording surface of the optical disc 18. The light reflected by the optical disc 18 is reflected by the objective lens 17, the aperture limiting filters 16, 1
Returning to the quarter wave plate 15 in order, the polarization beam splitter 14
And is focused by the detection lens 19 on the light receiving surface of the light receiving element 20. As is well known, the light receiving surface of the light receiving element 20 is divided into a plurality of parts, and a focus error signal and a tracking error signal can be obtained by observing the detection output balance of each light receiving surface.

In the example of the optical pickup using the optical integrated unit shown in FIG. 15B, the optical integrated unit 21
As shown in FIG. 15C, a light emitting element 26 made of a semiconductor laser and a light receiving element 20 made of a photodiode are mounted on a common stem, and a hologram element 22 is joined to a cap in the light emitting direction. Are arranged by A collimator lens 12 and a beam shaping prism 1 are provided on the optical path of light emitted from the integrated optical unit 21.
3. The objective lens 17 is arranged so as to be focused on the optical disc 18 as a light spot. The reflected light from the optical disk 18 follows the above path in the opposite direction and is diffracted by passing through the hologram 22 of the optical integrated unit 21, and the diffracted light is received by the light receiving element 20. The light receiving element 20 is also divided into a plurality of light receiving surfaces, and the focus error signal and the tracking error signal can be obtained from the detection signals of the respective light receiving surfaces.

As is clear from FIG. 15 (b), the optical pickup using the optical integrated unit has a reduced number of parts and a simple structure as compared with the optical pickup not using the optical integrated unit. Can be realized.

FIG. 16 shows an actual configuration example of an optical pickup using an optical integrated unit. The area inside the chain line is the optical pickup device. In order to prevent the optical pickup device from becoming bulky, the optical integrated unit 21 is oriented horizontally so that the light beam is emitted in the horizontal direction, and the raising mirror 23 is arranged between the collimator lens 12 and the objective lens 17 to emit the light beam. It is configured to stand up in a vertical direction, and an objective lens 17 forms a light spot on an optical disc 18 rotating in a horizontal plane. This conventional example has no beam shaping means.

The rising mirror 23 is arranged in front of the objective lens 17 in view of the structure and space requirement of a general optical disk drive, but the optical integrated unit 21 has an optical function related to recording and reproduction. And a collimator lens 12 and an objective lens 17 embedded in an actuator 25 movable in the focal direction.

The position of each optical element that requires high precision adjustment on the order of microns is the relative position of the light emitting element 26, the light receiving element 20, and the hologram element 22. The light beam from the light emitting element 26 passes through the hologram element 22, passes through the optical system of the optical pickup device including the objective lens 17 and is reflected by the optical disc 18, and then travels backward through the same optical system as the forward path to produce the hologram. The optical integrated unit 21 is packaged in advance so that a predetermined light spot is formed on the light receiving element 20 by being diffracted by the element 22. According to this optical pickup, the optical integrated unit 21, the collimator lens 12, the objective lens 17, and the raising mirror 23 can be assembled relatively easily without requiring strict accuracy. Further, since the optical element that needs to maintain a highly accurate positional relationship is packaged, it is not easily affected by a disturbance or the like and has excellent environment resistance. It also has the advantage of being small and lightweight.

However, since the DVD recording system pickup was put into practical use in recent years, an optical system to which a beam shaping means for compensating the output shortage of the light emitting element was added has been proposed and implemented. FIG. 17 shows an example of the configuration of an optical pickup device using an optical integrated unit and having a beam shaping function. The beam shaping means 13 is added between the collimator lens 12 and the rising mirror 23 to the configuration shown in FIG.

[0014]

A problem that arises when assembling this optical pickup device is the L shown in FIG.
The distance between D and CL, that is, the distance between the light emitting element 26 made of a semiconductor laser and the collimator lens 12.
In the case of an optical system having a beam shaping means, the above LD-CL
The accuracy of the distance is strictly required as compared with the non-beam shaping optical system.

Therefore, even if the optical integrated unit 21 is used,
In the optical system in which the beam shaping means for compensating for the insufficient output of the light emitting element is added as in the example shown in FIG.
As in the example shown in FIG. 6, the optical pickup device cannot be easily assembled, and the light emitting element 26 and the collimator lens 12 which require a highly accurate space are not packaged as one body, so that the environment resistance is high. Also deteriorates. In this way, some advantages of the optical integrated unit are lost.

In view of the problems of the prior art as described above, the present invention proposes the configuration of the hologram laser unit and the arrangement relationship of each optical element, and is small in size, light in weight, excellent in environmental resistance, and assembled as an optical pickup. An object is to provide an easy optical integrated unit.

[0017]

In order to solve the above problems, the present invention provides a light emitting element which emits a light beam for irradiating an optical disk, and a light receiving element which receives a light beam from the light emitting element reflected by the optical disk. In an optical integrated unit having a hologram element for diffracting a light flux reflected from an optical disc and a collimator lens for receiving a light flux from a light emitting element that has passed through the hologram element, the light emitting element, the light receiving element, the hologram element and the collimator lens are integrated. It is provided as a device of.

The integrated device may have beam shaping means for shaping the light beam from the collimator lens. The collimator lens may have a beam shaping function.

The light emitting element may have a plurality of light sources. A single collimator lens is arranged for the light emitting element having a plurality of light sources, and the light flux from the collimator lens emitted from the light emitting element and guided through the hologram element is emitted to the light emitting element light source on the shortest wavelength side. It is advisable to arrange the collimator lens so that parallel light or substantially parallel light is obtained.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an optical integrated unit according to the present invention will be described below with reference to the drawings.
It should be noted that parts having the same functions as those of the conventional functional parts shown in FIGS. 15 to 17 are designated by common reference numerals. Figure 1
At the one end side of the cylindrical holder 27, the light emitting element 2
6 and a light emitting / receiving unit in which the light receiving elements 20 are arranged side by side in the vicinity thereof are fitted. The light emitting element 26 is made of, for example, a semiconductor laser, and the light receiving element 20 is made of, for example, a photodiode divided into a plurality of light receiving surfaces. The collimator lens 12 is fitted into the other end of the holder 27. A hologram element 22 is arranged between the light emitting / receiving unit and the collimator lens 12. Thus, the optical integrated unit 30 is configured.

The light emitting element 26 emits a light beam for illuminating an optical disk (not shown). The light receiving element 20 receives the light flux from the light emitting element 26 reflected by the optical disc. The hologram element 22 diffracts the reflected light beam from the optical disc and makes it enter the light receiving element 20. The collimator lens 12 receives the light flux from the light emitting element 26 that has passed through the hologram element 22 and converts it into a parallel light flux or a substantially parallel light flux. The components of the optical integrated unit 30 include at least the light emitting element 26, the light receiving element 20, the hologram element 22,
The collimator lens 12. Depending on the application, a functional component such as a wave plate may be added, but basically it is composed of the above-mentioned four types of optical functional components.

With respect to the positional relationship between the above optical components, the light flux from the light emitting element 26 passes through the hologram element 22, passes through the collimator lens 12, and then exits the optical integrated unit 30, and the objective lens of the optical pickup device. Is reflected by the optical disc after passing through the optical system such as, and then returns to the optical integrated unit 30 by following the same optical system as the forward path.
The light passes through the collimator lens 12, is diffracted by the hologram element 22, and is guided to the light receiving element 26.
It is arranged so that a predetermined light spot is formed on the surface 6. Regarding the light emitting element 26 and the collimator lens 12, the collimator lens 12 with respect to the light emitting element 26 is so arranged that the light flux emitted from the light emitting element 26, transmitted through the hologram element 22, and transmitted through the collimator lens 12 becomes parallel light or substantially parallel light. Set the position of. Therefore, a parallel light flux or a substantially parallel light flux is emitted from this optical integrated unit 30.

The optical integrated unit 31 shown in FIG. 2 is of a type in which the beam shaping means 13 is added to the embodiment shown in FIG. The beam shaping means 13 includes a collimator lens 12
Is fixed to the end surface of the cylindrical holder 27 in close proximity to, and is arranged at a position where the collimator lens 12 receives a light flux that has become a parallel light flux or a substantially parallel light flux, and shapes the beam shape. Therefore, a beam-shaped parallel light beam or a substantially parallel light beam is emitted from the optical integrated unit 31,
This luminous flux is guided to the objective lens.

The optical integrated unit 32 shown in FIG. 3 and the optical integrated unit 33 shown in FIG.
The holding mode of the collimator lens 12 and the beam shaping means 13 is changed. In the embodiment shown in FIGS. 1 and 2,
Although each optical component is fixed to the cylindrical holder 27, in the embodiment shown in FIGS. 3 and 4, the holder 28 that cantileverly holds the lower portion of each optical component is used. The configuration and arrangement of the optical components of the embodiment shown in FIG. 3 are the same as those of the embodiment shown in FIG. 1, and are of a type that does not have beam shaping means. The configuration and arrangement of the optical parts of the embodiment shown in FIG. 4 are the same as those of the embodiment shown in FIG. The functions of the embodiment shown in FIGS. 3 and 4 are equivalent to those of the embodiment shown in FIGS.

The optical integrated unit 34 shown in FIG.
The beam shaping means of the embodiment shown in FIG. 4 is changed from a transmission type to a reflection type. The embodiment shown in FIG.
Similar to the embodiment shown in FIG. 4, a holder 28 that holds the lower portion of each optical component in a cantilever manner is used. This holder 2
A beam shaping means 29, which also functions as a rising mirror, which fixes a light beam which is transmitted through the hologram element 22 and transmitted through the collimator lens 12 to be parallel or approximately parallel at a right angle, is fixed at 8. An objective lens is arranged on the optical path reflected by the beam shaping means 29 so that the light beam whose cross-sectional shape is shaped is focused on the optical disc as a light spot.

In all the embodiments shown in FIGS. 1 to 5,
Light emitting element 26, light receiving element 20, and hologram element 22
Is generated by the hologram element 22 diffracting the light flux emitted from the light emitting element 26 and reflected by the optical disc.
The light receiving elements 20 are arranged in a relative positional relationship so that a predetermined light spot is formed. If a collimator lens with a beam shaping function is used, it is possible to configure an optical integrated unit including the beam shaping function with the configuration shown in FIGS. 1 and 3.

FIG. 6 shows a structural example of an optical pickup using the optical integrated unit 30 shown in FIG. The inside of the one-dot chain line is the optical pickup device. In FIG. 6, it comprises only an optical integrated unit 30, a beam shaping unit 13, a raising mirror 23, and an objective lens 17 embedded in an actuator 25 movable in the focal direction and the tracking direction. The cross-sectional shape of the parallel light flux or the substantially parallel light flux emitted from the optical integrated unit 30 is shaped by the beam shaping means 13, is raised by the raising mirror 23, and a light spot is formed on the recording surface of the optical disc 18 by the objective lens 17. To be done. The reflected light from the recording surface of the optical disc 18 follows the above path in reverse, returns to the optical integrated unit 30, passes through the collimator lens 12, is diffracted by the hologram element 22, and forms a light spot on the light receiving element 20.
A focus error signal and a tracking error signal can be obtained from the detection output of the light receiving element 20 having a plurality of light receiving surfaces, and these error signals are fed back to the actuator 25 to control the position of the objective lens. Tracking control can be performed.

According to this optical pickup device, the optical integrated unit 30, the beam shaping means 13, the objective lens 17,
Since the raising mirror 23 can be easily assembled without requiring strict accuracy, and the elements that need to maintain a highly accurate positional relationship are packaged,
It is possible to maintain the original meaning or effect of the optical integrated unit, which is excellent in environmental resistance such as disturbance.

FIG. 7 shows a structural example of an optical pickup using the optical integrated unit 31 shown in FIG. In FIG.
Since the optical integrated unit 31 has the beam shaping means 13, the optical pickup device has a configuration in which the objective lens embedded in the optical integrated unit 31, the raising mirror 23, and the actuator 25 movable in the focus direction and the tracking direction. It is composed of only 17.

FIG. 8 shows a configuration example of an optical pickup device using the optical integrated unit 34 shown in FIG. This optical pickup device is composed only of an optical integrated unit 34 and an objective lens 17 embedded in an actuator 25 that is movable in the focus direction and the tracking direction. 7,
Even with the two configuration examples shown in FIG. 8, it is possible to maintain the original meaning or effect of the optical integrated unit that is excellent in environmental resistance against disturbances and the like.

Next, an example of an optical integrated unit having a plurality of light sources will be described. An optical pickup device having a plurality of light sources performs recording / reproduction while performing high-speed recording / reproduction by multi-beams or switching between recording media (optical disks) having different recording densities with the same optical pickup device having compatibility. Required in some cases. In the former case, a plurality of light emitting elements are made to emit light simultaneously and used. In the latter case,
Using a light emitting element with a wavelength compatible with the target recording medium,
The light emitting element to be used will be selected according to the recording medium.

FIG. 13 shows a structural example of an optical integrated unit having a plurality of light emitting elements as described above. The components of this optical integrated unit are a plurality of light emitting elements 41 and 42, a light receiving element 20, a hologram element 22, a collimator lens 12, and a beam shaping member 13. The configuration is substantially the same as that of the embodiment shown in FIG. 1, except that a plurality of light emitting elements are provided. Depending on the application, a functional component such as a wave plate may be added, but basically, the optical functional component is used.

As for the positional relationship of the above-mentioned respective components, the light beams from the respective light emitting elements 41 and 42 pass through the hologram element 22, pass through the collimator lens 12, and then exit the optical integrated unit 35. 35 and an optical system of an optical pickup device having an objective lens and the like to form a light spot on the optical disc, and the reflected light from the optical disc follows the same optical system as the outward path and enters the optical integrated unit 35. Then, the light is passed through the collimator lens 12 and diffracted by the hologram element 22 so that a predetermined light spot is formed on the light receiving element 20.

Regarding the light emitting element and the collimator lens 12, when there are a plurality of light emitting elements 41 and 42 of the same wavelength, the collimator lens is emitted from all the light emitting elements 41 and 42 and is guided through the hologram element 22. The position of the collimator lens 12 is set so that the light flux from the light beam 12 is parallel light or substantially parallel light on average.
Place against. When there are a plurality of light emitting elements that emit light of different wavelengths, the light flux emitted from the light emitting element of the shortest wavelength and transmitted through the hologram element 22 and guided from the collimator lens 12 becomes parallel light or substantially parallel light. As described above, the position of the collimator lens 12 is set to the light emitting element 41,
42.

9 to 12 show various examples of a light emitting device having a plurality of light sources. In the optical pickup device, when a plurality of normal light emitting elements 26 are mounted side by side as in the example shown in FIG. 9, the distance between the optical axes becomes about 300 μm or more, and a plurality of light emitting elements among the optical components including the objective lens are emitted. If there is an optical component commonly used for the element, the optical axis shift of the light emitting element with respect to the optical system becomes large, which hinders the performance of the optical pickup device.

As a technique for solving this problem, a configuration example of the light emitting element shown in FIGS. 10 to 12 can be considered. Figure 10
The example shown in (1) is an example of a light emitting element having a monolithic structure in which a single light emitting element 36 has two light emitting points. Figure 1
In the example shown in 1, the two light emitting elements 3 whose light emitting points are biased toward the ends
This is an example in which the light emitting points 7 and 37 are arranged close to each other and are arranged side by side. In the example shown in FIG. 12, two normal light emitting elements 26, 26 are arranged with their light emitting surfaces facing each other, and a micromirror 38 is arranged between them, so that the light emitting elements 26, 26 emit light in the horizontal direction. The light beams are reflected by the micromirrors 38 at right angles so as to be parallel to each other.

By devising the structure as shown in FIGS. 10 to 12, the distance between the optical axes can be reduced to about 100 μm or less, and an optical pickup device having no optical axis deviation can be constructed. It is possible to provide an optical integrated unit capable of performing the above.

FIG. 14 shows such an optical integrated unit 35.
An example of the configuration of an optical pickup device using is shown. The optical pickup device shown in FIG. 14 is provided with an optical integrated unit, a rising mirror, an objective lens, and the like, like the example of the optical pickup device shown in FIGS. 6, 7, and 8. The only difference is that an optical integrated unit 35 having a plurality of light emitting elements 41, 42 is used. As described above, even in an optical pickup device having a plurality of light emitting elements, the original meaning or effect of the optical integrated unit, which is excellent in environmental resistance such as disturbance, can be maintained.

[0039]

In the optical integrated unit according to the first aspect of the present invention, a light emitting element that emits a light beam for irradiating the optical disk, a light receiving element that receives the light beam from the light emitting element reflected by the optical disk, and a reflected light beam from the optical disk are provided. By providing a hologram element that diffracts and a collimator lens that receives the light flux from the light emitting element that has passed through the hologram element as an integrated device, elements that require maintaining a highly accurate relative positional relationship are packaged. Thus, it is possible to realize an optical pickup device which is excellent in environmental resistance against disturbances and the like and which is easy to assemble and adjust.

In the structure of the optical integrated unit according to the second aspect, a light emitting element that emits a light beam for irradiating the optical disk, a light receiving element that receives the light beam from the light emitting element reflected by the optical disk, and a reflected light beam from the optical disk are provided. By providing a hologram element for diffracting, a collimator lens that receives a light beam from the light-emitting element that has passed through the hologram element, and a beam shaping unit that shapes the light beam from the collimator lens as an integrated device, a highly accurate relative position can be obtained. The elements that need to maintain the relationship are packaged, and an optical pickup device having excellent environmental resistance against disturbances can be realized. Further, it is possible to realize an optical pickup device that is easy to assemble and adjust.

According to the optical integrated unit of claim 3,
A light emitting element that emits a light beam that irradiates the optical disc, a light receiving element that receives the light beam from the light emitting element that is reflected by the optical disc, a hologram element that diffracts the reflected light beam from the optical disc, and a light emitting element that transmits the hologram element. By equipping a collimator lens with a beam shaping function that receives the light flux as an integrated device, the elements that need to maintain a highly accurate relative positional relationship are packaged, and they have excellent environmental resistance against external disturbances and are assembled. It is possible to realize an optical pickup device that is easy to adjust.

According to the invention of claim 4, claim 1,
In the invention described in 2 or 3, the hologram device diffracts a light beam emitted from the light emitting element and reflected by the optical disc by the hologram element so that a predetermined light spot is formed on the light receiving element. By arranging so as to be formed, it is possible to realize an optical integrated unit having excellent environmental resistance against disturbances and the like and having easy assembly and adjustment, as described in claim 1, 2, or 3. .

According to the optical integrated unit of claim 5,
The elements that need to maintain a highly accurate positional relationship are packaged, so they have excellent environmental resistance against disturbances, etc.
By providing two or more light sources of the light emitting element, it is possible to realize a recording medium having a different recording density, and it is possible to realize an optical pickup device for multi-wavelength which is easy to assemble and adjust. . Then, it is possible to realize an optical pickup device compatible with multi-beams.

According to the invention of claim 6, in the invention of claim 5, when a single collimator lens is arranged for a plurality of light emitting elements, the collimator is for the light source of the light emitting element on the shortest wavelength side. By arranging the collimator lens so that the light flux from the lens becomes parallel light or substantially parallel light, the adjustment with the one having the highest required positional accuracy with the collimator lens among the light emitting elements is optimized,
It is possible to realize an optical integrated unit applicable to a multi-wavelength compatible optical pickup device capable of supporting recording media having different recording densities.

[Brief description of drawings]

FIG. 1 is a sectional view in an optical axis direction showing an embodiment of an optical integrated unit according to the present invention.

FIG. 2 is a sectional view in the optical axis direction showing another embodiment of the optical integrated unit according to the present invention.

FIG. 3 is a sectional view in the optical axis direction showing yet another embodiment of an optical integrated unit according to the present invention.

FIG. 4 is a sectional view in the optical axis direction showing yet another embodiment of an optical integrated unit according to the present invention.

FIG. 5 is a sectional view in the optical axis direction showing yet another embodiment of an optical integrated unit according to the present invention.

FIG. 6 is an optical layout diagram showing an example of an optical pickup device using the optical integrated unit according to the present invention.

FIG. 7 is an optical layout diagram showing another example of an optical pickup device using the optical integrated unit according to the present invention.

FIG. 8 is an optical layout diagram showing still another example of an optical pickup device using the optical integrated unit according to the present invention.

FIG. 9 is a perspective view showing an example of a light emitting element having a plurality of light sources applicable to the present invention.

FIG. 10 is a perspective view showing another example of a light emitting element having a plurality of light sources applicable to the present invention.

FIG. 11 is a perspective view showing still another example of a light emitting element having a plurality of light sources applicable to the present invention.

FIG. 12 is a perspective view showing still another example of a light emitting element having a plurality of light sources applicable to the present invention.

FIG. 13 is a sectional view in the optical axis direction showing yet another embodiment of an optical integrated unit according to the present invention.

FIG. 14 is an optical layout diagram showing still another example of an optical pickup device using the optical integrated unit according to the present invention.

FIG. 15 shows an example of a conventional optical pickup device, (a) is a perspective view showing an example in which a light emitting element, a light receiving element and the like are not unitized, and (b) is a light emitting element, a light receiving element, etc. A perspective view showing an example of an integrated unit,
(C) is a perspective view showing a portion of the optical integrated unit.

FIG. 16 is an optical layout diagram showing an example of a conventional optical pickup device.

FIG. 17 is an optical layout diagram showing another example of a conventional optical pickup device.

[Explanation of symbols]

12 Collimator lens 13 Beam shaping means 17 Objective lens 18 optical disc 20 Light receiving element 22 Hologram element 26 Light-emitting element 30 Optical integrated unit

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01S 5/022 H01L 31/02 B 5F088 (72) Inventor Yusuke Taneda 1-3 Nakamagome, Ota-ku, Tokyo No. 6 F-Term in Ricoh Co., Ltd. (Reference) 2H049 CA05 CA09 CA15 CA20 2H087 KA13 LA25 RA44 RA45 RA46 5D119 AA01 AA36 AA38 AA41 BA01 BB01 BB03 BB05 EC45 EC47 FA05 FA08 FA30 JA02 A06 A41 BA01 A01 A41 BA01 AA36 A01 AA36 BA01 A38 A01 A41 A01 AA36 AA38 A01 FA05 FA08 FA30 JA02 JA06 JA14 5F073 AB06 AB27 BA04 EA29 FA23 FA30 5F088 AA01 BA15 BA16 BB10 EA09 EA20 JA12 JA20

Claims (6)

[Claims] 1. A light emitting element that emits a light beam to illuminate an optical disk, a light receiving element that receives the light beam from the light emitting element reflected by the optical disk, a hologram element that diffracts a light beam reflected from the optical disk, and the hologram. An optical integrated unit comprising a collimator lens that receives a light flux from the light emitting element that has passed through the element as an integrated device. 2. A light emitting element that emits a light beam to illuminate an optical disk, a light receiving element that receives the light beam from the light emitting element reflected by the optical disk, a hologram element that diffracts a light beam reflected from the optical disk, and the hologram. An optical integrated unit comprising a collimator lens that receives a light beam from the light emitting element that has passed through the element and a beam shaping unit that shapes the light beam from the collimator lens as an integrated device. 3. A light emitting element that emits a light beam to irradiate an optical disk, a light receiving element that receives the light beam from the light emitting element reflected by the optical disk, a hologram element that diffracts a reflected light beam from the optical disk, and the hologram. An optical integrated unit comprising a collimator lens with a beam shaping function that receives a light beam from the light emitting element that has passed through the element as an integrated device. 4. The light emitting element, the light receiving element, and the hologram element form a predetermined light spot on the light receiving element by diffracting the light beam emitted from the light emitting element and reflected by the optical disk by the hologram element. The optical integrated unit according to claim 1, 2 or 3, wherein the optical integrated units are arranged in such a relative positional relationship. 5. The optical integrated unit according to claim 1, wherein the light emitting element includes a plurality of light sources. 6. A single collimator lens is arranged for a light emitting element having a plurality of light sources, and the light emitting element is emitted to the light emitting element light source on the shortest wavelength side,
6. The optical integrated unit according to claim 5, wherein the collimator lens is arranged so that a light beam from the collimator lens that is guided through the hologram element becomes parallel light or substantially parallel light.