JP2002358789A - Optical memory element and its reproducing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable adjusting (alignment of incident light) easily and surely the irradiation state of incident light (reproduction light) for an optical memory element. SOLUTION: This element is optical memory element 10 constituted as a laminated body which comprises resin core layers 2A, 2B, resin clad layers 3A, 3B laminated on both surfaces of resin core layers and in which a plurality of optical waveguide members having ruggedness part in at least either of boundary of the resin core layer and the resin clad layer are laminated, and a plurality of optical waveguide members are constituted of optical waveguide members 323A for data of one or plurality and optical waveguide members 323B for servo used for adjusting an irradiation state of incident light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical memory device and a method for reproducing the same, and more particularly, to a method suitable for manufacturing an optical memory device using an optical waveguide device.
The present invention relates to an optical memory device and a reproducing method thereof.

[0002]

2. Description of the Related Art In recent years, a technique has been proposed in which light is introduced into a planar (card-shaped) optical waveguide in which a pattern is cut in advance so as to generate predetermined scattered light, and an image is formed outside the optical waveguide surface. (IEEE Photon.Technol.Lett., Vol.9, p
p.958-960, JULY1997, etc.). That is, as schematically shown in FIG. 10, for example, a core (layer) 101 whose refractive index and film thickness are adjusted so as to function as an optical waveguide, and both sides (both sides) sandwiching the core layer 101 In the card-type slab-type optical waveguide device 100 including the (first and second) claddings (layers) 102 provided on the substrate, fine irregularities are present at the interface between the core layer 101 and the cladding layer 102. In this case, when light (laser light) is introduced into the core layer (optical waveguide) 101 through the lens 103, a part of the introduced light is scattered at the uneven portion, and the scattered light exits through the cladding layer 102 to the outside. come.

Therefore, the scattering intensity and the phase of light that can form a specific image at a predetermined distance from the optical waveguide surface (optical waveguide 101) are calculated, and a fine uneven pattern corresponding to the calculation is previously formed in the core layer 101. In this case, a desired image can be formed outside the optical waveguide surface. That is, the core layer 101 functions as an information recording layer.

[0004] For example, the scattered light coming out of the optical waveguide surface is set at the above-mentioned predetermined distance to the CCD receiver 104.
To form a two-dimensional digital pattern (for example, a binary pattern of light and dark or a multi-valued pattern based on lightness (gray scale)) to generate a digital signal. A desired image processing can be performed on the formed image by a processing device (not shown).

Further, as schematically shown in FIG. 11, for example, when a plurality of optical waveguides (recording layers) 101 are laminated by repeatedly laminating the cladding layer 102 and the core layer 101, a certain optical waveguide is formed. The light scattered at 101 crosses another optical waveguide 101, but usually,
Since the refractive index difference between the optical waveguide 101 and the cladding layer 102 is extremely small, the scattered light hardly re-scatters due to the unevenness formed on another optical waveguide 101, and the image formed is not disturbed.
Therefore, many images and patterns can be formed in proportion to the number of layers.

That is, the optical waveguide device 100 can be used as an optical memory element (a recording medium such as a ROM) having a capacity proportional to the number of layers. It is said that this optical memory element can theoretically have a capacity of about 1 gigabyte in one layer, and can be stacked up to about 100 layers. It is expected to be used as a large-capacity ROM that can sufficiently cope with recording and the like.

The above-mentioned fine concavo-convex pattern in the core layer 101 of the optical waveguide device 100 is formed, for example, by the following method. That is, first, as schematically shown in FIG. 12A, a photoresist is applied on a flat glass or the like to be the (first) cladding layer 102, and exposure with light or an electron beam is performed. By development, pits (concavo-convex pattern) corresponding to the image to be formed are formed on the glass (cladding layer 102).

Thereafter, the core layer 10 is formed on the uneven pattern.
Form one. As a result, the core layer 101 on which the concavo-convex pattern is formed is manufactured, and by further forming the second cladding layer 102 on the core layer 101, an optical waveguide device (optical memory element) for one layer is manufactured. . Then, in the same manner as described above, an uneven pattern is formed on the cladding layer 102 by exposure and development, and the core layer 101 is formed thereon.
By repeatedly performing the formation of FIG.
As schematically shown in FIG. 1, an optical memory element 100a having a multilayer structure (hereinafter, sometimes referred to as "multilayer optical memory") 100a is manufactured.

However, in such a method using exposure and development, it takes a very long time and cost to fabricate the optical memory element 100 for one layer. Therefore, it is necessary to fabricate a large-capacity multilayer optical memory 100a. It takes enormous time and cost. For this reason, by making the core layer and the clad layer made of resin, the above-mentioned concave and convex pattern can be easily formed, and an optical memory element capable of holding a larger volume of information in a limited volume is easily and inexpensively manufactured. (Japanese Patent Application No. 11-1315).
12, Japanese Patent Application No. 11-131513).

[0010]

By the way, in order to reproduce information recorded in the optical memory element, incident light (reproducing light; for example, laser light) which is incident on the optical memory element is used.
(For example, focal length, irradiation position, irradiation angle, inclination of reproduction light, etc.) are adjusted so as to be in an optimum state for reproducing the optical memory element (alignment of incident light incident on the optical memory element is performed). )There is a need.

In this case, the reproduced image from the optical memory element is represented by C
Reading is performed by a CD receiver, and alignment of incident light is performed using the reproduced image. However, there are a variety of reconstructed images, some of which are not suitable for aligning incident light. For example, if the reproduced image is entirely dark (low luminance) or has little difference in brightness (no difference in luminance), it is difficult for the CCD receiver to read the reproduced image. It is difficult, and it is difficult to use this to align the incident light.

On the other hand, even if the reproduced image is bright overall (high luminance), if the irradiation state of the incident light (irradiation position, irradiation angle, focal length, inclination) is not good,
Only part of the incident light is incident on the core layer of the optical memory element,
The reproduced image may be dark (low brightness) or only a part of the image may be reproduced.
It is difficult to read a reproduced image by a CD receiver, and it is difficult to align incident light using the reproduced image.

[0013] Even if a reproduced image can be read by a CCD receiver, the reproduced image often does not have a uniform brightness (brightness). It is difficult to align light.
The present invention has been made in view of such a problem, and is capable of easily and reliably adjusting the irradiation state (alignment of incident light) of incident light (reproducing light) on an optical memory element. And an optical memory device and a method for reproducing the same.

[0014]

An optical memory device according to the present invention comprises a resin core layer and a resin clad layer laminated on both sides of the resin core layer. An optical memory element configured as a laminated body formed by laminating a plurality of optical waveguide members each having an uneven portion on at least one of the interfaces with the resin clad layer, wherein the plurality of optical waveguide members include one or more data optical waveguides. It is characterized by comprising a wave member and a servo optical waveguide member that can be used for adjusting the irradiation state of incident light.

Preferably, the servo uneven portion of the servo optical waveguide member is configured to output a servo pattern extending over substantially the entire length in a width direction orthogonal to the waveguide direction of the incident light. ). It is preferable that the optical waveguide member for servo is provided on the outermost side of the laminate.

Furthermore, it is preferable that the servo irregularities of the servo optical waveguide member are formed at positions different from the data irregularities of the data optical waveguide member. Further, it is preferable that the image formed by the servo irregularities of the servo optical waveguide member is formed at a position different from the image formed by the data irregularities of the data optical waveguide member. Item 5).

Further, a plurality of data optical waveguide members are laminated,
It is preferable that the interval between the resin core layer of the servo optical waveguide member and the resin core layer of the adjacent data optical waveguide member is larger than the interval between the resin core layers of the adjacent data optical waveguide members. (Claim 6). Further, it is preferable that the maximum luminance of the servo pattern from the optical waveguide member for servo be higher than the maximum luminance of the reproduced image from the optical waveguide member for data.

Here, the "maximum luminance" refers to the luminance of a portion set to have the highest luminance when the servo pattern or the reproduced image is set to have a plurality of gradations. Preferably, the refractive index of the resin core layer of the optical waveguide member for servo is larger than the refractive index of the resin core layer of the optical waveguide member for data.

Further, it is preferable that the refractive index of the resin clad layer of the optical waveguide member for servo is smaller than the refractive index of the resin clad layer of the optical waveguide member for data. In addition, it is preferable that the height of the servo unevenness of the servo optical waveguide member is higher than the height of the data unevenness of the data optical waveguide member. Further, it is preferable that the resin core layer of the servo optical waveguide member is thicker than the resin core layer of the data optical waveguide member.
1).

Further, it is preferable that the servo uneven portion of the servo optical waveguide member is configured to have only intensity information. According to a thirteenth aspect of the present invention, there is provided a method for reproducing an optical memory element according to any one of the first to twelfth aspects, wherein information obtained by reproducing a servo optical waveguide member is provided. After adjusting the irradiation state of the incident light based on the above, the data optical waveguide member is reproduced.

The optical memory device according to the present invention comprises a resin core layer and a resin clad layer laminated on both sides of the resin core layer. An optical memory element configured as a laminated body formed by laminating a plurality of optical waveguide members each having an uneven portion on at least one of the interfaces, and a reproduced image obtained by an outermost optical waveguide member laminated on the outermost side of the laminate. It is characterized in that the maximum luminance is higher than the maximum luminance of a reproduced image obtained by another optical waveguide member.

Here, the "maximum luminance" refers to the luminance of a portion set to have the highest luminance when the servo pattern or the reproduced image is set to have a plurality of gradations. Preferably, the uneven portions of the outermost optical waveguide member are formed at positions different from the uneven portions of the other optical waveguide members.

Also, the image formed by the concave and convex portions of the outermost optical waveguide member is formed at a position different from the image formed by the concave and convex portions of the other optical waveguide members. . Also, a plurality of other optical waveguide members are laminated,
It is preferable that the distance between the resin core layer of the outermost optical waveguide member and the resin core layer of another adjacent optical waveguide member is larger than the distance between the adjacent resin core layers of the other optical waveguide members. (Claim 17).

Further, it is preferable that the refractive index of the resin core layer of the outermost optical waveguide member is larger than the refractive index of the resin core layer of the other optical waveguide members. It is preferable that the refractive index of the resin clad layer of the outermost optical waveguide member is smaller than the refractive index of the resin clad layer of the other optical waveguide members. Furthermore, it is preferable that the height of the concave and convex portions of the outermost layer optical waveguide member is higher than the height of the concave and convex portions of the other optical waveguide members.

It is preferable that the resin core layer of the outermost optical waveguide member is thicker than the resin core layers of the other optical waveguide members. Further, it is preferable that the concave and convex portions of the outermost layer optical waveguide member are configured to have only the intensity information (claim 22). An optical memory element reproducing method according to claim 23 is the optical memory element reproducing method according to any one of claims 14 to 22, wherein the light is incident on the basis of information obtained by reproducing the outermost optical waveguide member. After the adjustment of the light irradiation state, the reproduction of another optical waveguide member is performed.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical memory device (optical memory, multilayer optical memory) and a reproducing method according to an embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 9, the basic configuration of the optical memory device [laminated (planar) optical memory device; laminated waveguide hologram device, MWH device] according to the present embodiment is as shown in FIG. It is configured as a laminate in which a plurality of optical waveguide members 323 each composed of a core layer 2 and a resin clad layer 3 are laminated. Here, it is assumed that the resin film 4 is also attached.

Here, the optical waveguide member 323 is composed of a resin core layer 2 and a resin clad layer 3 laminated on both surfaces of the resin core layer 2. At least one of the interfaces with the layer 3 has an uneven portion (information uneven portion) 5. Hereinafter, such an optical memory device 1
The method for manufacturing the laminate constituting No. 0 will be described.

First, as shown in FIG. 8 (A), a predetermined pattern (concavo-convex shape; pit) corresponding to an image (information) to be formed on the surface is stamped on a stamper 1. A core material (liquid core resin) 2 'is applied to a thickness. In the present embodiment, the core material 2 ′ is made of an ultraviolet-curable resin agent that is cured by irradiating ultraviolet light (UV light). And completely cured to form a resin core layer 2 '.

Next, after the core material 2 'is completely cured as described above, as shown in FIG. 8B, an ultraviolet curable resin material having a smaller refractive index than the core layer 2' is further formed thereon. (A liquid clad resin) 3a 'is applied and cured by ultraviolet irradiation to form a resin clad layer 3a' having a lower refractive index than the core layer 2 '. Then, FIG.
As shown in (C), the same clad material 3b 'as the clad material 3a' is applied on the clad layer 3a ', and a resin film (resin film member) 4 serving as a support is formed on the clad material 3b', for example. Adhesion (lamination) is performed while applying pressure using a roller or the like. That is, the resin film 4 is laminated on the clad layer 3a 'via the clad material 3b'.

In this state, if the clad material 3b 'is cured by irradiating ultraviolet rays, the clad layer 3b' made of the same material as the clad layer 3a 'is formed, and the resin film 4 is bonded. Here, the cladding layers 3a ', 3
Since b 'is made of the same clad material, it functions as one clad layer 3'. Then, as shown in FIG. 8 (D), a member 2′3′4 composed of the core layer 2 ′, the cladding layers 3 ′ (3a ′, 3b ′) and the resin film 4 is integrally formed from the stamper 1. Peel (separate).

Next, as shown in FIG. 8E, a core layer 2 "and a clad layer 3a" are similarly coated on a stamper 1 "having a desired concavo-convex pattern of the next layer, respectively, and irradiated with ultraviolet rays. Thereafter, as shown in FIG. 8F, the clad material 3 is formed on the clad layer 3a ″.
The same clad material 3b "as that of a" is applied, and the members 2'3'4 are adhered thereon. After the clad material 3b ″ is cured by ultraviolet irradiation, as shown in FIG.
From the stamper 1 ″, the above-mentioned core layer 2 ″ and cladding layer 3 ″
(3a ", 3b") and the members 2'3'4 are integrally peeled off.

By repeating the above process, a resin clad layer 3 and a resin core layer 2 are formed on at least one surface of a resin film 4 as a support (substrate) as shown in FIG. An optical memory element 1 as a laminate in which two or more clad / core members each having an uneven portion 5 at an interface between a resin clad layer 3 and a resin core layer 2 are laminated.
0 is formed.

Here, as shown in FIG.
Since the core member is fragile, the resin film 4
Two or more clad / core members are laminated on top,
Further, the resin film 4 is adhered to the two resin films 4.
The structure is sandwiched between. This is the optical memory device 1
0 is because the effect of protection between the two resin films 4 is higher when the resin film 4 is manufactured (in particular, when the optical memory element 10 is cut). Note that the structure does not have to be sandwiched between the resin films. For example, the resin film may be attached to only one surface, or the resin film may not be attached.

As described above, the optical memory element 10 can be reliably protected by using the two support members as the two resin films 4, and the resin film 4 has an appropriate flexibility (flexibility). Is also preferable from the viewpoint of handling during production. The two supports need not necessarily be made of the same material, but may be made of different materials.

Here, the resin core layer 2 and the resin clad layers 3 laminated on both surfaces of the resin core layer 2 are used.
And a plurality of slab-type optical waveguide devices (optical waveguide members) 323 provided with an uneven portion 5 on at least one of the interfaces between the resin core layer 2 and the resin clad layer 3. It can also be seen as forming a body.

In this case, a plurality of laminated optical waveguide members 3
Reference numeral 23 also serves as one clad layer between two adjacent optical waveguide members. Therefore, when five clad layers and core layers are laminated, for example, clad layer / core layer / cladding layer / core layer / cladding layer, two optical waveguide members 323 are laminated to form an optical memory as a laminate. Element 1
0 has been formed.

In this embodiment, the adjacent cladding layer is commonly used as one layer. However, the present invention is not limited to this, and a three-layer laminate (cladding layer / core layer / cladding layer) (optical waveguide) may be used. The member 323 may have a basic configuration, and a plurality of optical waveguide members 323 may be laminated with or without a support such as the resin film 4 interposed therebetween. Further, the optical waveguide members can be laminated with an adhesive. Here, as the adhesive, for example, a clad material that functions as a clad layer after curing can be used.

Further, the curl of the laminated body may be suppressed by laminating a clad / core member or providing another resin layer on the back side of the resin film 4 as a support in the same manner. it can. In the above description, any resin may be used as the core material 2 as long as it is a liquid at the time of application and can be cured thereafter. Examples thereof include a photo-curable resin such as a resin and a thermosetting resin. However, when the transfer is performed by the stamper as described above, it is preferable to use a photocurable resin, for example, an acrylic resin, an epoxy resin, or a thiol resin.

The clad material 3 may be any material (resin) that is transparent and has a refractive index slightly smaller than that of the core material 2. However, it is convenient to apply a clad material 3 made of various resins. The clad material 3 made of a photocurable resin, a thermosetting resin, or the like has excellent adhesiveness to the resin film 4 and is suitable. The method of applying the core material 2 and the clad material 3 includes:
For example, there are a spin coating method, a blade coating method, a gravure coating method, a die coating method and the like, and any coating method may be used as long as the coating film thickness and the uniformity are satisfied.

Here, it is preferable that the thickness of the laminate formed by laminating the optical waveguide members 323 is about 0.3 mm or more in order to obtain strength. More preferably, it is about 0.5 mm or more. However, optical memory (information recording medium) such as optical card
In consideration of the portability as described above, it is preferable that the thickness be about 5 mm or less. More preferably, it is about 3 mm or less. In the present embodiment, as the support, various materials such as resin and metal are used as long as they can function as a support for holding the laminate (optical memory element 10). If you need flexibility, such as doing
It is preferable to use a resin support. Various types of curable resins may be cured after being applied, or the resin may be dissolved in a solvent and applied and dried to form a resin support. This is preferable in terms of productivity and workability.

Specifically, the resin film 4 is made of polycarbonate, amorphous polyolefin such as ARTON (manufactured by JSR), PET (polyethylene terephthalate), P
It is preferable to use a thermoplastic resin film having excellent optical properties such as EN (polyethylene naphthalate) (PEN is further excellent in heat resistance) (particularly, PET or PE described above).
N is preferable because it is easy to obtain a film having a uniform thickness), and it is preferable that any of these is made to have a thickness of, for example, 100 μm or less by a method such as hot stretching or solvent casting.

Generally, in the manufacturing process of the resin film 4, an optically scattering material such as inorganic particles is mixed into the film. If scattering of light by scatterers in the film becomes a problem when reading signals,
If the clad / core member is laminated only on one side of the film, it is preferable to use a light-shielding film as the film or to provide a light-shielding film between the film and the clad / core member. Accordingly, it is possible to prevent light from propagating into the resin film or interference of scattered light within the film with the signal light.

In this case, it is more preferable to make the support itself light-shielding, because the size of the optical memory element 10 can be reduced and the manufacturing process can be simplified. Here, examples of the light-shielding film and the light-shielding film include a PET film produced by kneading carbon into a resin or adding a dye. The light-shielding film or the wavelength region in which the light-shielding film acts is sufficient if the wavelength of the introduced light (incident light, reproduction light) used for reproduction can be shielded, and it is not necessary to shield the entire visible light region. Absent. Regarding the light-shielding performance, it is sufficient that 90% or more of the light can be blocked in the film thickness direction, but it is more preferable that 99% or more of the light can be blocked.

The thickness of the core layer 2 and the cladding layer 3 may be any thickness as long as the core layer 2 and the cladding layer 3 can function as an optical waveguide. In the wavelength region, the core layer 2 is approximately 0.5 to
It is considered to be about 3.0 μm. In this case, the thickness of the cladding layer 3 is not particularly limited, but is preferably 100 μm or less in consideration of reducing the overall thickness. If the lower limit is stipulated, it will be 0.1 μm or more.

The cladding layer 3 is preferably formed in two layers as described above, since the film thickness is preferably stable, but may be formed as one layer. In the above description, the resin film 4
Although a method using a single-wafer film has been described as an example, implementation using a continuous film is also possible. By combining processes such as coating the core and clad material on the film with a die coater, microgravure, bar coater, etc., and curing the core and clad material while pressing the stamper, the clad / core member is formed on the support. Can be manufactured. Further, by using a roll stamper processed into a form that can be wound up into a roll as the stamper, it is possible to improve the productivity of the transfer process from the stamper.

The optical memory device 10 constructed as described above
For example, when light is introduced into the core layer 2 as an optical waveguide through the incident end face, the introduced light is propagated while being scattered at the uneven portion of the interface. The scattered light at this time propagates (transmits) in the vertical direction (intersecting direction) with respect to the introduced light, and is finally emitted to the outside from both sides of the optical memory element, and an image corresponding to the uneven pattern is formed. An image will be formed.

As described above, according to this embodiment, both the laminated core layer 2 and clad layer 3 are made of resin,
In addition, since the curable resin that can be cured by light, heat, or the like is used for the core layer (core material) 2 on which the unevenness is formed, it is not necessary to use the photoresist exposure and development processing as in the related art. By the transfer from the stamper, it is possible to easily form the uneven portion 5 having a desired shape at the interface between the core layer 2 and the clad layer 3.

The cladding layer 3 has a thickness of, for example, 10 μm.
By setting it to about m, the film thickness of the element can be suppressed to about 1 mm even when 100 layers are stacked, and a practical optical memory element 10 having a multilayer structure can be manufactured. Accordingly, mass production of the optical memory element 10 having a multilayer structure becomes possible, and the optical memory element 10 can be provided more easily (in a shorter time) and at lower cost than before.

Incidentally, in order to reproduce information recorded in such an optical memory element 10, incident light (reproducing light; for example, laser light or the like) incident on the optical memory element 10 is used.
(For example, the focal length, the irradiation position, the irradiation angle, the inclination of the reproduction light, etc.) are adjusted so as to be in an optimum state for reproducing the optical memory element 10 (the alignment of the reproduction light incident on the optical memory element 10). Take).

In this embodiment, as shown in FIG. 2, incident light from a light source is converted into a lens (for example, a cylindrical lens;
The optical waveguide 12 is formed into an oval shape extending in the width direction of the optical memory element 10 by the optical system 12 and is incident on the resin core layer 2 of the optical waveguide member 323 constituting the optical memory element 10.
The information recorded in the optical memory element 10 is reproduced by reading the scattered light scattered by the 23 uneven portions 5 with the CCD receiver 13. FIG. 2 shows only one layer of the optical waveguide member 323 of the optical memory element 10 configured by laminating a plurality of layers.

In this embodiment, the lens 12 with respect to the optical memory element 10 is adjusted to adjust the irradiation state (for example, focal length, irradiation position, irradiation angle, inclination of the incident light, etc.) of the incident light (reproducing light) to the optical memory element 10. The position, angle, and tilt are controlled. Here, the position, angle,
As the control of the inclination, there is the following control (see FIG. 2).
reference). Vertical position control of lens 12 (Z-direction position control) Remote-direction position control of lens 12 (Y-direction position control; distance control between optical memory element 10 and lens 12, position control in the direction along the incident direction of incident light) ) Horizontal position control of lens 12 (X position control; position control in a direction orthogonal to the incident direction of incident light) Elevation angle control of lens 12 (angle control, rotation direction position control) Vertical tilt control of lens 12 The vertical irradiation position of the incident light is adjusted by the horizontal tilt control of the lens 12 and the vertical position control. Further, the distance (focal length) of the focal point of the incident light is adjusted by the separation direction position control (distance control). Further, the horizontal irradiation position of the incident light is adjusted by the horizontal position control. The elevation angle control adjusts the irradiation angle of the incident light. Further, the inclination of the incident light is adjusted by the vertical inclination control. Further, the horizontal tilt control controls the focal length (focal length) of the incident light.

It should be noted that it is not always necessary to perform all the above-mentioned controls (1) to (3) for controlling the position, angle, and inclination of the lens 12. For example, if the optical memory element (medium) 10 has sufficient mechanical accuracy (for example, the positional relationship between the optical memory element 10 and the lens 12) when it is loaded into a drive, the remote position control, the horizontal position control, etc. It is not necessary to perform the fine adjustment by the elevation angle control and the horizontal tilt control, and it is sufficient to perform at least the vertical position control and the fine adjustment by the vertical tilt control.

However, the mechanical accuracy is not sufficient and the lens 12
When it is necessary to adjust the focal length of the incident light to be made incident through the, it is necessary to perform fine adjustment by controlling the position in the separation direction. If the mechanical accuracy is not sufficient and the angle (orientation) or inclination of the lens 12 may be shifted, the elevation angle control, the vertical inclination control,
It is necessary to make fine adjustments by horizontal tilt control.

Further, in the horizontal position control, since it is sufficient if the width of the incident light covers the entire uneven portion 5 provided on the optical waveguide member 323, it is necessary to perform fine adjustment by this control. Is considered low. When the lens 12 has an integral structure with the light source as the incident light irradiation device, the position of the incident light irradiation device,
The irradiation state of the incident light may be adjusted by controlling the angle and the inclination.

In this embodiment, the position, angle, and inclination of the lens 12 and the incident light irradiation device are controlled to adjust the irradiation state of the incident light. However, the present invention is not limited to this. By controlling the position, angle, and inclination of the holding mechanism that holds the optical memory element 10 in order to change the relative positional relationship between the optical memory element 10 and the lens 12, the incident light irradiation device, and the like, the light incident on the optical memory element 10 is changed. The light irradiation state may be adjusted.

As described above, when reproducing the optical memory element 10, it is necessary to align the incident light to be incident on the optical memory element 10. Therefore, in this embodiment, in order to facilitate the alignment of the incident light. As shown in FIG. 1, the optical memory element 10 is used for one or a plurality of data optical waveguide members (data layer, information optical waveguide member, information layer) 323A for recording desired data (information) and a servo. And at least one servo optical waveguide member (servo layer) 323B for recording obtained servo information (which can be used for alignment of incident light).

Here, apart from one or a plurality of data optical waveguide members 323A for recording desired data, a servo optical waveguide member 323B designed to facilitate alignment of incident light is provided. Optical memory device 10
This makes it easy to align the incident light to be incident on the. As shown in FIG. 1, the optical memory element 10 has an uneven portion 5 (provided at the interface between the resin core layer 2 (2A, 2B) and the resin clad layer 3 (3A, 3B, 3AB)). 5A, 5B), an incident end face (incident light introduction end face) 11 for guiding the incident light (reproducing light) for reading the information to the resin core layers 2A, 2B of the optical waveguide members 323A, 323B.

Here, the end face of each optical memory element 10 cut into a desired size at 90 degrees (the angle formed with the surface of the optical waveguide member is 90 degrees) is defined as an incident end face (90-degree incident end face) 11. . The incident light is applied to the resin core layer 2.
The incident end face 11 for guiding to A and 2B is not limited to this, and various types can be considered. For example, one end face of the optical memory element 10 is cut at 45 degrees (an angle made with the surface of the optical waveguide member is 45 degrees), and a reflection film is formed as necessary to form a mirror end face (inclined end face, micro mirror). Alternatively, this mirror end face may be used as the incident end face (45 ° incident end face). In this case, light is incident on the 45 ° incident end face from a direction perpendicular to the surface of the optical memory element 10 and is reflected by the 45 ° incident end face to guide the incident light to the resin core layers 2A and 2B. Will be.

When the optical memory element 10 is reproduced, first, the alignment of the incident light with respect to the optical memory element 10 is performed based on the servo pattern (reproduction pattern) obtained by reproducing the servo optical waveguide member 323B. The light irradiation state is adjusted), and thereafter, the data optical waveguide member 323A is reproduced (a method of reproducing an optical memory element).

Hereinafter, the optical memory device 1 according to this embodiment will be described.
A specific configuration of the servo optical waveguide member 323B of No. 0 will be described. First, in the present embodiment, in order to quickly perform coarse positioning in a servo operation described later,
The servo optical waveguide member 323B is laminated on the outermost side of the optical memory element 10. That is, as shown in FIG. 1, the servo optical waveguide member 323B is replaced with the data optical waveguide member 323B.
A is provided above the uppermost layer or below the lowermost layer. For this reason, the optical waveguide member for servo 323B is also referred to as an outermost optical waveguide member.

As described above, the servo optical waveguide member 323B
Is provided on the outermost side of the optical memory element 10, even if the thickness of the cladding layer 3AB is increased in order to suppress crosstalk, as described later,
Since only the thickness of B is increased, the optical memory element 10
The overall thickness can be reduced. That is, when the servo optical waveguide member 323B is provided between the data optical waveguide member 323A, it is preferable to increase the thickness of the cladding layers 3 on both sides of the servo optical waveguide member 323B in order to suppress crosstalk. Preferably, the thickness of the entire optical memory element 10 is increased, whereas the optical waveguide member 323 for servo is used.
If B is provided on the outermost side, it is only necessary to increase the thickness of one clad layer 3 in order to suppress crosstalk,
The thickness of the entire optical memory device 10 can be reduced.

If the rough positioning in the servo operation can be quickly performed by another method and the crosstalk can be suppressed by another method, the servo optical waveguide member 323 can be used.
B need not be provided on the outermost side of the optical memory element 10.
Further, in the present embodiment, the optical memory element 10B reads the reproduced image formed by the scattered light scattered by the data unevenness portion 5A and the servo unevenness portion 5B and emitted from one side to the outside to read the data. It may be configured as a single-sided optical memory element for reproducing information on the uneven portion 5A or the servo uneven portion 5B, or may be scattered by the data uneven portion 5A or the servo uneven portion 5B and emitted from both sides to the outside. A double-sided reproduction optical memory element that reads a reproduced image formed by the scattered light and reproduces information of the data uneven portion 5A and the servo uneven portion 5B may be used.

In particular, in the present embodiment, the servo concavo-convex portion 5B of the servo optical waveguide member 323B is provided with a servo optical waveguide member so that alignment of incident light in a servo operation described later can be performed easily and reliably. The servo pattern from 323B is formed so as to be brighter (brighter) than the reproduced image from the data optical waveguide member 323A.

More specifically, the servo optical waveguide member 323B
Of the servo optical waveguide member 323B
The brightness of the servo pattern from the optical waveguide member 32 for data
It is formed so as to be higher than the maximum luminance of the reproduced image from 3A. That is, in the present embodiment, the data optical waveguide member 3
The data unevenness portion 5A of 23A is formed by setting a data pattern of an image to be formed into a set of pixels having a square of several microns square as a basic pixel, and setting the luminance for each pixel, Since the reproduced image is displayed at a predetermined gradation (a plurality of gradations), the servo uneven portion 5B of the servo optical waveguide member 323B forms the data uneven portion 5A of the data optical waveguide member 323A. Therefore, the luminance is formed to be higher than the highest luminance (the luminance of a portion set to have the highest luminance) among the luminances set for the above.

For example, when the reproduced image from the data concave and convex portion 5A of the data optical waveguide member 323A is expressed by four gradations, the portion of the servo pattern where the brightness is set to be the brightest among the four levels ( The servo concavo-convex portion 5B of the servo optical waveguide member 323B is formed so as to have a higher luminance than that of a portion set to have the highest luminance. When the servo pattern is represented by a predetermined gradation (a plurality of gradations), the highest luminance of the servo pattern from the servo optical waveguide member 323B (the luminance of the portion set to have the highest luminance) is obtained. The servo concavo-convex portion 5B of the servo optical waveguide member 323B is formed so as to be higher than the maximum luminance of the reproduced image from the data optical waveguide member 323A.

Preferably, the servo optical waveguide member 323B
Is set to be 1.1 times or more (more preferably 1.2 times or more) the maximum brightness of the reproduced image from the data optical waveguide member 323A. Unless this difference is made, it cannot be said that the servo pattern by the servo optical waveguide member 323B is brightened, and it is difficult to perform servo adjustment easily and quickly. However, it is preferable to set it to three times or less. If it is made too bright, other data optical waveguide members 323 may be used.
This is because crosstalk increases when A is reproduced.

In this way, the optical waveguide member 323 for servo is used.
When the servo uneven portion 5B of B is configured, the evaluation of the optical memory element 10 including the servo optical waveguide member 323B can be performed, for example, as follows. In other words, only the luminance (maximum luminance) of the portion set to have the highest luminance of the reproduced image from the data uneven portion 5A of the data optical waveguide member 323A represented by the predetermined gradation is picked up. , And compare the average luminance of the reproduced image with the luminance (maximum luminance) of the servo pattern.
The optical memory element 10 can be evaluated by determining whether or not the luminance (maximum luminance) of the servo pattern is higher than the average luminance of the reproduced image.

In this case, since the evaluation is performed using the average luminance of the portion set to have the highest luminance of the reproduced image, the maximum luminance of the reproduced image is not affected by the noise in the reproduced image. The optical memory element 10 can be evaluated based on (the luminance of the portion where the luminance of the reproduced image is set to be the highest) and the luminance of the servo pattern (the highest luminance).

Specifically, the servo optical waveguide member 323B
The servo optical waveguide member 323B is configured such that the refractive index of the core 2B of the data optical waveguide member 323A is larger than the refractive index of the core 2A of the data optical waveguide member 323A. This makes it possible to increase the scattering of the incident light (guided light) on the servo uneven portion 5B of the servo optical waveguide member 323B, and as a result, the output from the servo optical waveguide member 323B increases (scattered light). And the servo pattern becomes brighter.

In particular, the refractive index of the core 2B of the servo optical waveguide member 323B is determined by the core 2B of the data optical waveguide member 323A.
It is preferable to make the refractive index of A larger than 0.001 or more. On the other hand, if the brightness is too high, crosstalk in reproducing the data optical waveguide member 323A increases, so that the refractive index of the core 2B of the servo optical waveguide member 323B and the core 2A of the data optical waveguide member 323A. Is preferably 0.1 or less.

On the other hand, on the contrary, the servo optical waveguide member 323B
Of the optical waveguide member 323 for data
The optical waveguide member 323B for servo may be configured to be smaller than the refractive index of the cladding 3A of A. Thereby, the servo irregularities 5B of the servo optical waveguide member 323B are formed.
In this case, the scattering of the incident light can be increased, and as a result, the output from the servo optical waveguide member 323B increases (the luminance of the scattered light increases), and the servo pattern becomes bright. In this case, two clad layers having different refractive indices are laminated between the servo optical waveguide member 323B and the data optical waveguide member 323A.

In particular, the refractive index of the core 2B of the servo optical waveguide member 323B is determined by the core 2B of the data optical waveguide member 323A.
It is preferable to make the refractive index of A larger than 0.001 or more. On the other hand, if the brightness is too high, crosstalk in reproducing the data optical waveguide member 323A increases, so that the refractive index of the core 2B of the servo optical waveguide member 323B and the core 2A of the data optical waveguide member 323A. Is preferably 0.1 or less.

As described above, the servo optical waveguide member 323B
If the difference in the refractive index between the core 2B and the cladding 3B is larger than the difference in the refractive index between the core 2A and the cladding 3A of the data optical waveguide member 323A, the servo of the servo optical waveguide member 323B can be realized. The scattering of the incident light at the concave / convex portion 5B can be increased, and as a result, the output from the servo optical waveguide member 323B increases (the luminance of the scattered light increases), and the servo pattern becomes bright.

When the difference in the refractive index between the core 2B and the clad 3B of the servo optical waveguide member 323B is increased,
If the thickness of the resin core layer 2B is the same, multi-mode is likely to occur. Therefore, when a single mode is desired, it is necessary to increase the difference in the refractive index between the core 2B and the cladding 3B of the servo optical waveguide member 323B, and at the same time, to reduce the thickness of the resin core layer 2B.

Generally, the thickness of the resin core layer 2B is 2 μm
The following is the single mode. For example, by setting the thickness of the core 2A of the servo optical waveguide member 323A to about 1.4 μm, the waveguide mode can be made a single mode. However, if a complete multi-mode is desired, the thickness of the resin core layer 2B may be increased as described later.

In the present embodiment, as shown in FIG. 1, the servo irregularities 5B of the servo optical waveguide member 323B are formed.
Is made higher than the height of the data uneven portion 5A of the data optical waveguide member 323A. This makes it possible to increase the scattering at the servo uneven portion 5B of the servo optical waveguide member 323B, and as a result, the servo optical waveguide member 32
The output from 3B increases (the brightness of the scattered light increases), and the servo pattern becomes bright.

The height of the servo uneven portion 5B of the servo optical waveguide member 323B can be changed by changing the pit depth of the stamper. In particular, the optical waveguide member for servo 323
The height of the servo uneven portion 5B of B is preferably 1.1 times or more (more preferably 1.2 times or more) the height of the data uneven portion 5A of the data optical waveguide member 323A.
On the other hand, if the brightness is too high, the crosstalk when reproducing the other data optical waveguide member 323A increases, so that the height of the servo uneven portion 5B of the servo optical waveguide member 323B is reduced. It is preferable that the height is not more than three times the height of the data uneven portion 5A of the wave member 323A.

Further, in the present embodiment, as shown in FIG. 1, in order to make incident light easily enter the resin core layer 2B of the servo optical waveguide member 323B (ie, to make coupling easy). , Servo optical waveguide member 323B
The thickness of the resin core layer 2B is changed to the data optical waveguide member 323.
The thickness is larger than the thickness of the resin core layer 2A. When the resin core layer 2B is thickened as described above, a multimode is formed. However, the multimode is easier to optically couple (coupling) than the single mode, and scattered light is also easily emitted to the outside. Because the servo pattern is also bright,
Servo (alignment of incident light) can be performed easily and reliably.

As described above, when the thickness of the resin core layer 2B is increased, the mode becomes multi-mode. Therefore, even if the servo uneven portion 5B of the servo optical waveguide member 323B is formed so as to form a hologram image. Although scattered light is not formed and a hologram image is not formed, there is no problem even if scattered light is not formed because it is only used for servo (alignment of incident light).

In particular, the thickness of the resin core layer 2B of the servo optical waveguide member 323B is 1.1 times or more (more preferably, 2 times or more) the thickness of the resin core layer 2A of the data optical waveguide member 323A. ) Is preferable. On the other hand, in consideration of increasing the storage capacity while reducing the thickness (film thickness) of the entire optical memory element 10, the thickness of the resin core layer 2B of the servo optical waveguide member 323B is preferably set to 100 μm or less.

In the present embodiment, as described above, in order to make the servo pattern from the servo optical waveguide member 323B brighter (having a higher brightness) than the reproduced image from the data optical waveguide member 323A, various types are used. Although it is assumed that the conditions are satisfied, it may be configured that any one of these conditions is satisfied. As described above, in the present embodiment, the servo optical waveguide member 323B is configured to be multi-mode,
The servo uneven portion 5B of 3B is formed as a grating having only intensity information.

That is, the data projection / recess portion 5A of the data optical waveguide member 323A is formed to have intensity information and phase information, and the hologram is scattered by the data projection / recess portion 5A of the data optical waveguide member 323A. An image (reproduced image) is formed, which is read by the CCD receiver 13 to reproduce data (information) recorded on the data optical waveguide member 323A. Servo uneven portion 5B of member 323B
Has only intensity information and does not have phase information. The scattered light scattered by the servo irregularities (grating, diffraction grating) 5B of the servo optical waveguide member 323B is formed outside the optical memory element 10. By not reading the image (ie, not forming a hologram image) and reading the mere scattered light by the CCD receiver 13, the servo optical waveguide member 323 is read.
The servo pattern recorded in B is reproduced. In this case, the scattered light scattered by the servo uneven portion 5B of the servo optical waveguide member 323B does not form an image, but there is no problem in using it for servo (alignment of incident light).

In this embodiment, since the resin optical core layer 2B of the servo optical waveguide member 323B is thickened so as to be in the multi-mode, the servo optical waveguide member 323B is formed.
The servo uneven portion 5B of B is configured to have only intensity information, but is not limited to this. The thickness of the resin core layer 2B of the servo optical waveguide member 323B is reduced to reduce the single mode. And the optical waveguide member 32 for servo
The 3B servo concavo-convex portion 5B may be configured to have intensity information and phase information. In this case, the servo pattern (reproduced pattern) is formed as a hologram image (reproduced image, output image) by the scattered light scattered by the servo concavo-convex portion 5B of the servo optical waveguide member 323B and emitted to the outside. Become.

Here, there are various multi-modes from a single mode to a complete multi-mode, and the degree to which phase information is not used gradually increases as the mode becomes a single mode. An image close to the single mode is slightly more blurred than the reproduced image in the single mode, but in a complete multi mode, it is merely scattered light, and the entire image is blurred and no image is formed.

The servo optical waveguide member 323B
Are used for alignment of incident light, and as described above, the servo pattern is formed so as to scatter the incident light as much as possible to make the servo pattern as bright as possible. ) Has a great effect on the reproduced image (crosstalk increases).

For this reason, in the present embodiment, as shown in FIG. 1, the servo concavo-convex portion 5B of the servo optical waveguide member 323B is provided with the data concavo-convex portion 5B of the data optical waveguide member 323A.
It is formed at a position different from the position where A is formed. As a result, as shown in FIG. 3A, the data optical waveguide member 323A read by the CCD
3 is displayed as a hologram image in a substantially central area, while the reproduction image 14 is obtained as shown in FIG.
The servo pattern 15 from the servo optical waveguide member 323B read by the D receiver 13 is a servo pattern having uniform brightness with respect to the background, and is located in a region different from the region where the data optical waveguide member 323A is displayed. Will be displayed. FIG. 3B shows a servo pattern obtained as a hologram image.

Thus, at the time of servo (alignment of incident light), the scattered light scattered by the servo uneven portion 5B of the servo optical waveguide member 323B is reflected by the data optical waveguide member 32.
Since the light is emitted to the outside of the optical memory element 10 without passing through the optical waveguide 3A, the servo optical waveguide 3 is not affected by the data optical waveguide 323A (ie, the crosstalk is suppressed).
The servo pattern 15 recorded in 23B can be reproduced. As a result, the alignment of the incident light is reliably performed without causing an alignment error.

When reproducing the information recorded on the data optical waveguide member 323A, the scattered light scattered by the data uneven portion 5A of the data optical waveguide member 323A passes through the servo optical waveguide member 323B. Therefore, the information recorded on the data optical waveguide member 323A is reproduced without being affected by the servo optical waveguide member 323B (ie, suppressing crosstalk). Can be.

Here, the servo optical waveguide member 32 is used.
The servo uneven portion 5B of 3B is connected to the optical waveguide member 32 for data.
Although formed at a position different from the position where the data uneven portion 5A of 3A is formed, the present invention is not limited to this. If the crosstalk can be suppressed, the servo optical waveguide member 323B is formed. The servo concavo-convex portion 5B may be formed at the same position as the data concavo-convex portion 5A of the data optical waveguide member 323A. This is preferable because the reproduced image from the data optical waveguide member 323A and the servo pattern from the servo optical waveguide member 323B can be read without changing the imaging range of the CCD receiver 13.

In the present embodiment, the servo pattern 15 read by the CCD receiver 13 includes a square portion (bright portion, high brightness portion) having uniform brightness (brightness) and a portion near the periphery (dark portion). , Low-luminance part; background), so that the servo optical waveguide member 32
A 3B servo uneven portion 5B is formed. In other words, a square part that is uniformly bright (high in luminance) is obtained as the servo pattern 15 with respect to the background with low luminance.
The servo irregularities 5B of the servo optical waveguide member 323B are formed.

Here, the servo pattern 15 corresponds to FIG.
As shown in (B), a band-shaped pattern extending substantially the entire length of the imaging range of the CCD receiver 13 in the width direction (vertical direction in the figure) set according to the size of the optical memory element 10 is provided. The servo irregularities 5B of the servo optical waveguide member 323B are formed. When the output (luminance of the scattered light) from the entire surface of the optical memory element 10 is read by the CCD receiver 13, when processing the signal read by the CCD receiver 13, the area of the servo pattern 15 (or the servo pattern) is processed. If signals from regions other than the region including the vicinity of the pattern 15) are not processed,
The time required for reading the servo pattern 15 can be reduced, and servo (alignment of incident light) can be performed in a short time.

Further, a detector (for example, a CCD receiver) is provided separately from the CCD receiver for reading the output from the data optical waveguide member 323A, and the servo irregularities of the servo optical waveguide member 323B are provided by the detector. The output from the area where 5B is formed (or the area including the vicinity thereof) may be read. Preferably, the servo pattern 15 from the servo optical waveguide member 323B and the reproduced image 14 from the data optical waveguide member 323A (the square part of the servo pattern 15 having a high luminance and the reproduced image 14) are 50.
The data concave / convex portion 5A of the data optical waveguide member 323A and the servo concave / convex portion 5B of the servo optical waveguide member 323B are formed so as to be separated by at least μm. This is because if the servo pattern 15 and the reproduced image 14 are too close, an alignment error is likely to occur.

On the other hand, if the distance between the servo pattern 15 and the reproduced image 14 is too long, the CCD receiver (CC
Since the D camera 13 needs to be moved, the thickness is preferably 500 μm or less. Here, the servo uneven portion 5B of the servo optical waveguide member 323B is formed so that the servo pattern 15 is a band-shaped pattern extending over substantially the entire width of the imaging range of the CCD receiver 13 in the width direction. , But is not limited to this.

For example, as shown in FIG. 4, the servo pattern is provided on both sides in the short direction of the imaging range of the CCD receiver 13 and includes two strip-shaped patterns extending in the long direction. The servo uneven portion 5 of the optical waveguide member 323B may be formed. Further, for example, as shown in FIG. 5, the servo uneven portion 5 of the servo optical waveguide member 323B may be formed such that the servo pattern is composed of a plurality of circular patterns. In this case, a CCD for reading an output from the data optical waveguide member 323A.
A plurality of detectors (for example, photodiodes or the like) may be provided separately from the receiver, and alignment of incident light may be performed based on information on how many circular patterns are detected by these detectors.

Further, in this embodiment, in order to suppress crosstalk, as shown in FIG. 1, the resin core layer of the data optical waveguide member 323A adjacent to the resin core layer 2B of the servo optical waveguide member 323B. The distance (distance) from 2A is
The distance (distance) between the resin core layers 2A, 2A of the data optical waveguide member 323A adjacent to each other is set to be larger.

Here, the data optical waveguide member 323 adjacent to the resin core layer 2B of the servo optical waveguide member 323B is used.
The thickness of the cladding layer 3AB between the resin core layer 2A and the resin core layer 2A of the data optical waveguide member 323A adjacent to each other is made larger than the thickness of the cladding layer 3A between the resin optical core layers 2A. Preferably, the servo optical waveguide member 323B
Optical waveguide member 32 adjacent to the resin core layer 2B of FIG.
The thickness of the clad layer 3AB between the resin core layer 2A and the resin core layer 2A of the data optical waveguide member 323A adjacent to each other is 1.times.
It is 5 times or more (more preferably, 2 times or more). This makes it possible to reliably suppress crosstalk.

However, the thickness of the cladding layer 3AB between the resin core layer 2B of the servo optical waveguide member 323B and the resin core layer 2A of the adjacent data optical waveguide member 323A is 2
The thickness is preferably not more than 00 μm. This is to increase the storage capacity while reducing the thickness (total film thickness) of the entire optical memory element 10. If the crosstalk can be sufficiently suppressed by another method, the distance between the resin core layer 2B of the servo optical waveguide member 323B and the resin core layer 2A of the adjacent data optical waveguide member 323A can be reduced. The thickness of the cladding layer 3AB does not have to be greater than the thickness of the cladding layer 3A between the resin core layers 2A of the optical waveguide member for data 323A.

Hereinafter, the optical memory element 1 in the case where the servo optical waveguide member 323B is formed on the basis of the above-described conditions.
An example of 0 will be described. For example, the optical memory element 10
Is configured by laminating 20 layers of the optical waveguide member 323A for data and one layer of the optical waveguide member 323B for servo.
It may be designed as follows.

That is, the data optical waveguide member 323A is
The refractive index of the clad is 1.51, its thickness is 10 μm, the refractive index of the core is 1.52, its thickness is 1.4 μm, and the shape of the data uneven portion 5A in the waveguide is its depth. Is 160 nm and the width is 200 nm. On the other hand, the optical waveguide member for servo 323B has a cladding refractive index of 1.51,
The film thickness is 10 μm, the refractive index of the core is 1.53, and the film thickness is 1.4 μm.
The shape of B has a depth of 160 nm and a width of 200 nm. The servo pattern from the servo concavo-convex portion 5B has a uniform brightness (luminance), and the size is 2.7 in length.
mm and a width of 100 μm.

In this case, the cladding layer 3AB between the data optical waveguide member 323A and the servo optical waveguide member 323B.
May be 50 μm. In this manner, the data optical waveguide member 323A and the servo optical waveguide member 323B have the same refractive index of the cladding 3 and the data optical waveguide member 323A.
Optical waveguide member 3 for servo than the refractive index of core 2A of 23A
By increasing the refractive index of the core 2B of the 23B, the output (luminance) of the servo optical waveguide member 323B can be made twice as large as the output (luminance) of the data optical waveguide member 323A.

Since the servo optical waveguide member 323 according to the present embodiment is configured as described above, the servo (servo operation) by the drive when reproducing the information recorded in the optical memory element 10 is as follows. For example, it is performed in the following order (1) and (2). The servo by the drive is not limited to this. (1) First, the incident light (for example, laser light) is scanned along the incident end face of the optical memory element 10, and the reproduced light is scanned so that the output of the CCD 13 is not saturated particularly at the servo optical waveguide member 323 </ b> B. Adjust the output. (2) Next, in order to align the incident light with respect to the optical memory element 10, the position, angle, and tilt of the lens 12 are controlled (the above-mentioned control (1)).

Here, alignment of incident light is performed based on the length and brightness (brightness) of the servo pattern read by the CCD receiver 13. For example, in order to align incident light, the position, angle,
When the vertical position control and the vertical direction control are performed as tilt control, the control is performed in the following order.

First, after the irradiation position of the incident light is aligned with the edge of the incident end face of the optical memory element 10, vertical position control is performed, so that the edge of the incident end face 11 of the optical memory element 10 is moved vertically (Z direction). (Thickness direction) to scan the optical waveguide member 323B for rough positioning of the irradiation position of the incident light. Next, based on the length of the servo pattern 15 read by the CCD receiver 13 (the length of the bright square portion of the servo pattern 15), vertical tilt control is performed to align the incident light.

Specifically, the incident light is shifted in the vertical direction (Z direction).
To detect a change in the servo pattern 15 (a change in a bright square portion of the servo pattern 15).
In this case, the manner of change of the servo pattern 15 is different depending on the degree of inclination of the incident light in the vertical direction. Adjust the deviation at.

Next, after the vertical tilt control is completed, the vertical position based on the brightness of the servo pattern 15 read by the CCD receiver 13 (the brightness of the bright square portion of the servo pattern 15; the brightness). Control is performed to align the incident light. Specifically, the vertical position control is performed to precisely scan the incident light in the vertical direction (Z direction) along the incident end face 11 of the optical memory element 10, where the output of the CCD 13 becomes maximum. By searching for the optical waveguide member 32 for servo.
Precise positioning of the irradiation position of the incident light on 3B is performed.

Here, the above control is performed, but based on the brightness (brightness) of the servo pattern 15 read by the CCD receiver 13,
The position of the incident light may be controlled to align the incident light. In this case, the separation direction position control of
After performing the above-described vertical position control and performing precise positioning, the lens 12 is moved to the optical memory element 10.
, And the focal length may be adjusted by searching for a location where the output of the CCD receiver 13 is maximized.

Further, the horizontal position control may be performed based on the length of the servo pattern 15 read by the CCD receiver 13 to align the incident light. In this case, the horizontal position control is performed after the above-described vertical position control is performed and fine positioning is performed, and then the irradiation position of the lens 12 is moved.
By searching for a place where the output of the CD receiver 13 is maximized,
The irradiation position may be adjusted.

Further, based on the brightness (brightness) of the servo pattern 15 read by the CCD receiver 13, elevation control and horizontal tilt control are also performed.
The incident light may be aligned. In this case, the elevation angle control and the horizontal tilt control are performed after the above-described vertical position control is performed and fine positioning is performed, and the angle and the focal length of the lens 12 are changed so that the output of the CCD receiver 13 is changed. The irradiation state (for example, irradiation angle and focal length) of the incident light may be adjusted by searching for a position where the maximum value is obtained.

Therefore, according to the optical memory device and the reproducing method of the present embodiment, the servo optical waveguide member 3
The provision of 23B has an advantage that alignment of incident light (reproducing light) with respect to the optical memory element 10 can be performed easily and reliably. In particular, the servo pattern from the servo optical waveguide member 323B is brighter (has a higher brightness) than the reproduced image from the data optical waveguide member 323A.
As a result, there is an advantage that the alignment of incident light can be performed more easily and more reliably.

Since the servo optical waveguide member 323B is provided on the outermost layer, there is an advantage that the alignment of the incident light with respect to the optical memory element 10 can be performed quickly. In particular, since the thickness of the core layer 2B of the optical waveguide member for servo 323B is large, it is easy to make incident light incident (coupling is easy) and alignment of the incident light becomes easy.

Further, a servo optical waveguide member 323B is provided, and the servo uneven portion 5B of the servo optical waveguide member 323B is provided at a position different from the data uneven portion 5A of the data optical waveguide member 323A. Has been
There are advantages that alignment of incident light with respect to the optical memory element 10 can be easily and reliably performed, and that crosstalk (interlayer crosstalk) can be suppressed.

Further, a servo optical waveguide member 323B is provided, and the core layer 2B of the servo optical waveguide member 323B is provided.
Since the cladding layer 3AB between the optical waveguide member 323A and the core layer 2A of the data optical member 323A is thick, the optical memory element 1
There is an advantage that alignment of incident light with respect to 0 can be performed easily and reliably, and that crosstalk (interlayer crosstalk) can be suppressed.

[0113]

According to the optical memory element and the reproducing method of the present invention described in claims 1 to 23, since the servo optical waveguide member is provided, the irradiation state of incident light (reproducing light) to the optical memory element can be reduced. Adjustment (alignment of incident light)
There is an advantage that it can be performed easily and reliably.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an overall configuration of an optical memory device according to one embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining alignment of incident light of the optical memory element according to one embodiment of the present invention.

3A and 3B are diagrams showing outputs from an optical memory element according to an embodiment of the present invention, wherein FIG. 3A shows a reproduced image from a data layer, and FIG. 3B shows a servo pattern from a servo layer. .

FIG. 4 is a view showing a modified example of a servo pattern from a servo layer of the optical memory element according to the embodiment of the present invention.

FIG. 5 is a diagram showing another modified example of the servo pattern from the servo layer of the optical memory device according to the embodiment of the present invention.

FIG. 6 is a diagram showing a servo pattern in the case where the optical memory element according to the embodiment of the present invention is aligned.

FIG. 7 is a diagram showing a servo pattern when the optical memory element according to one embodiment of the present invention is not aligned.

FIGS. 8A to 8G are schematic cross-sectional views for explaining a method of manufacturing a laminated body constituting the optical memory element according to one embodiment of the present invention.

FIG. 9 is a schematic cross-sectional view for explaining an example of a laminated structure of a laminated body constituting the optical memory element according to one embodiment of the present invention.

FIG. 10 is a schematic perspective view for explaining the operation principle of a conventional optical memory element.

FIG. 11 is a schematic perspective view for explaining the operation principle of a conventional optical memory element.

12A and 12B are schematic perspective views for explaining the operation principle of a conventional optical memory device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stamper 2, 2A, 2B Core layer 3, 3A, 3B Cladding layer 4 Resin film (support) 5 Uneven part 5A Uneven part for data 5B Uneven part for servo 10 Optical memory element 11 Incident end face 12 Lens 13 CCD receiver 14 Reproduction Image 15 Servo pattern (reproduction pattern) 323 Optical waveguide member 323A Optical waveguide member for data 323B Optical waveguide member for servo

Claims (23)

[Claims] 1. A resin core layer comprising: a resin core layer; and a resin clad layer laminated on both surfaces of the resin core layer, and at least one of interfaces between the resin core layer and the resin clad layer has an uneven portion. An optical memory device configured as a laminate formed by laminating a plurality of optical waveguide members having a plurality of optical waveguide members, wherein the plurality of optical waveguide members are one or a plurality of data optical waveguide members, and for adjusting the irradiation state of incident light. An optical memory element comprising: a servo optical waveguide member that can be used. 2. The servo uneven portion of the servo optical waveguide member is configured to output a servo pattern extending over substantially the entire length in a width direction orthogonal to a waveguide direction of incident light. The optical memory device according to claim 1, wherein 3. The optical memory device according to claim 1, wherein the optical waveguide member for servo is provided on an outermost side of the laminated body. 4. The servo optical waveguide member according to claim 1, wherein the servo uneven portion is formed at a position different from the data uneven portion of the data optical waveguide member. Item 2. The optical memory device according to item 1. 5. An image formed by the servo unevenness portion of the servo optical waveguide member is formed at a position different from an image formed by the data unevenness portion of the data optical waveguide member. Claim 1 characterized by the following:
4. The optical memory device according to any one of items 3 to 3. 6. A plurality of the data optical waveguide members are stacked, and a distance between a resin core layer of the servo optical waveguide member and an adjacent resin core layer of the data optical waveguide member is adjacent to each other. The optical memory device according to claim 1, wherein the distance is larger than a distance between resin core layers of the data optical waveguide member. 7. The apparatus according to claim 1, wherein a maximum brightness of a servo pattern from the optical waveguide member for servo is higher than a maximum brightness of a reproduced image from the optical waveguide member for data. The optical memory device according to any one of claims 1 to 6. 8. The servo optical waveguide member according to claim 1, wherein a refractive index of the resin core layer of the servo optical waveguide member is larger than a refractive index of the resin core layer of the data optical waveguide member. The optical memory device according to claim 1. 9. The servo optical waveguide member according to claim 1, wherein a refractive index of a resin clad layer of the servo optical waveguide member is smaller than a refractive index of the resin clad layer of the data optical waveguide member. The optical memory device according to claim 1. 10. The servo optical waveguide member according to claim 1, wherein a height of the servo uneven portion is higher than a height of the data uneven portion of the data optical waveguide member. The optical memory device according to claim 1. 11. The servo optical waveguide member according to claim 1, wherein a resin core layer of the servo optical waveguide member is thicker than a resin core layer of the data optical waveguide member. Optical memory device. 12. The optical memory device according to claim 1, wherein the servo uneven portion of the servo optical waveguide member has only intensity information. 13. The method for reproducing an optical memory device according to claim 1, wherein an irradiation state of incident light is based on a servo pattern obtained by reproducing the servo optical waveguide member. After adjusting the
A method for reproducing an optical memory element, comprising reproducing the data optical waveguide member. 14. A resin core layer and a resin clad layer laminated on both surfaces of the resin core layer, and at least one of the interfaces between the resin core layer and the resin clad layer has an uneven portion. An optical memory device configured as a laminate obtained by laminating a plurality of optical waveguide members having the following structure, wherein the highest luminance of the reproduction pattern obtained by the outermost layer optical waveguide member laminated on the outermost side of the laminate has another value. An optical memory device characterized in that it is configured to be higher than the maximum brightness of a reproduced image obtained by an optical waveguide member. 15. The optical memory device according to claim 14, wherein the uneven portion of the outermost optical waveguide member is formed at a position different from the uneven portion of the other optical waveguide member. 16. An image formed by the uneven portion of the outermost optical waveguide member is formed at a position different from an image formed by the uneven portion of the other optical waveguide member. The optical memory device according to claim 14, characterized in that: 17. The optical waveguide member according to claim 17, wherein a plurality of the other optical waveguide members are stacked, and a distance between the resin core layer of the outermost optical waveguide member and the adjacent resin core layer of the other optical waveguide member is the other. 17. The optical waveguide member according to claim 14, wherein the distance between the adjacent resin core layers is larger than a distance between the adjacent resin core layers.
An optical memory device according to item 1. 18. The optical waveguide according to claim 14, wherein the refractive index of the resin core layer of the outermost optical waveguide member is larger than the refractive index of the resin core layer of the other optical waveguide member. The optical memory device according to claim 1. 19. The optical waveguide member according to claim 14, wherein a refractive index of the resin clad layer of the outermost optical waveguide member is smaller than a refractive index of the resin clad layer of the other optical waveguide member.
19. The optical memory element according to any one of items 18 to 18. 20. The method according to claim 14, wherein the height of the uneven portion of the outermost optical waveguide member is higher than the height of the uneven portion of the other optical waveguide member. An optical memory device according to claim 1. 21. The optical waveguide member according to claim 14, wherein a resin core layer of the outermost optical waveguide member is thicker than a resin core layer of the other optical waveguide member. Optical memory device. 22. The optical memory device according to claim 14, wherein the uneven portion of the outermost layer optical waveguide member is configured to have only intensity information. 23. The reproducing method for an optical memory device according to claim 14, wherein the irradiation state of the incident light is based on a reproduction pattern obtained by reproducing the outermost optical waveguide member. Reproducing the optical waveguide member after performing the adjustment of (1).