WO2005119669A1 - 光記録再生装置用光ヘッド - Google Patents
光記録再生装置用光ヘッド Download PDFInfo
- Publication number
- WO2005119669A1 WO2005119669A1 PCT/JP2005/009946 JP2005009946W WO2005119669A1 WO 2005119669 A1 WO2005119669 A1 WO 2005119669A1 JP 2005009946 W JP2005009946 W JP 2005009946W WO 2005119669 A1 WO2005119669 A1 WO 2005119669A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- light
- optical
- optical head
- light source
- recording medium
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
- G11B7/135—Means for guiding the beam from the source to the record carrier or from the record carrier to the detector
- G11B7/1356—Double or multiple prisms, i.e. having two or more prisms in cooperation
Definitions
- the present invention relates to an optical head used for optical information processing or optical communication, and more particularly, to an optical head for an optical recording / reproducing device.
- DVDs digital 'versatile' disks
- CDs compact 'disks'
- NA numerical aperture
- Patent Document 1 discloses an optical head that reproduces and records digital information using a blue laser light source.
- FIG. 12 is a schematic diagram showing a configuration of a conventional optical head.
- 91 is a polarizing beam splitter
- 92 is a 1Z4 wavelength plate
- 93 is an optical element for correcting spherical aberration
- 94 is an objective lens
- 95 is an optical recording medium
- 96 is a focusing lens
- 97 is a multi-lens
- 98 is light. It is a detector.
- the incident laser light is, for example, blue light having a wavelength of 450 nm or less, which is emitted from a GaN-based laser and converted into parallel light.
- the polarization beam splitter 91 is an optical element having different transmittance and reflectance depending on the incident polarization.
- the polarizing beam splitter 91 is used for splitting light.
- the 1Z4 wave plate 92 is an optical element formed of a birefringent material. The 1Z4 wave plate 92 is used to convert linearly polarized light to circularly polarized light.
- the spherical aberration correcting optical element 93 is an optical element for correcting spherical aberration that occurs when the base material thickness of the optical recording medium 95 deviates from a predetermined optimum base material thickness.
- the spherical aberration can be corrected by changing the distance between the concave lens and the convex lens.
- the objective lens 94 is a lens that focuses light on the recording layer of the optical recording medium 95, and is composed of two groups and two lenses.
- the focusing lens 96 is a lens that condenses the light reflected on the recording layer of the optical recording medium to the photodetector 98.
- the multi-lens 97 has a cylindrical incident surface and a rotationally symmetric surface with respect to the optical axis of the lens.
- the multi-lens 97 has an astigmatic difference to enable detection of a focus error signal by a so-called astigmatism method.
- the photodetector 98 receives the light reflected by the recording layer of the optical recording medium 95 and converts the light into an electric signal.
- the operation of the optical head thus configured will be described.
- the blue parallel light having a wavelength of 450 nm or less emitted from the GaN laser passes through the polarizing beam splitter 91, enters the quarter-wave plate 92, and converts linearly polarized light into circularly polarized light.
- the circularly polarized light transmitted through the 1Z4 wavelength plate 92 is incident on the spherical aberration correcting optical element 93.
- the incident parallel light is converted into a concave lens and a convex lens constituting the spherical aberration correcting optical element 93.
- the optical recording medium 95 By changing the interval of the light, it is converted into divergent light or convergent light.
- the converted light enters the objective lens 94, is given a spherical aberration according to the degree of divergence or convergence of the incident light, and is condensed on the optical recording medium 95.
- the light to which the wavefront aberration has been given is incident on the objective lens 94 and collected. . Therefore, on the optical recording medium 95, a light spot having no aberration, that is, a light spot narrowed to the diffraction limit is formed.
- the circularly polarized light reflected from the optical recording medium 95 passes through the spherical aberration correcting optical element 93 and enters the 1Z4 wavelength plate 92.
- This reflected light is converted by the quarter-wave plate 92 into linearly polarized light having a polarization direction orthogonal to the polarization direction of the laser light propagating toward the optical recording medium 95.
- the linearly polarized light converted by the 1Z4 wavelength plate 92 is reflected by the polarization beam splitter 91 and enters the focusing lens 96. This light is converged by a focusing lens 96, given astigmatism by a multi-lens 97, and collected by a photodetector 98.
- the photodetector 98 outputs a focus error signal indicating the focus state of the light on the optical recording medium 95, and outputs a tracking error signal indicating the irradiation position of the light on the optical recording medium 95.
- the focus error The difference signal and the tracking error signal are detected by a known technique, for example, by an astigmatism method and a three-beam method.
- the focus control means controls the position of the objective lens 94 in the optical axis direction based on the focus error signal so that the light is always focused on the optical recording medium 95 in a focused state.
- the tracking control means controls the position of the objective lens 94 based on the tracking error signal so that the light is focused on a desired track on the optical recording medium 95. Further, information recorded on the optical recording medium 98 is also obtained from the photodetector 98. With such a configuration, the spherical aberration caused by the deviation of the substrate thickness of the optical recording medium 95 from the optimum substrate thickness can be corrected using the spherical aberration correcting optical element 93.
- the optical head having such a configuration can reproduce and record digital information even when light having a wavelength of 450 nm or less is used as a light source.
- Patent document 1 JP-A-2000-131603
- the laser light emitted from the light source and converted into parallel light passes through the polarization beam splitter 91 on the outward path of the optical path, and the optical recording is performed.
- Head to medium 95 That is, a very large amount of blue light for recording and reproducing information passes through the polarizing beam splitter 91. Therefore, the layer of adhesive material (adhesive layer) included in the polarization beam splitter 91 is irradiated with a large amount of blue light and gradually deteriorates, and the transmittance and aberration of the polarization beam splitter itself deteriorates, and A problem arises in that the recording characteristics and reproduction characteristics of the head deteriorate.
- An object of the present invention is to use a prism (polarizing beam splitter) having an adhesive layer that causes light deterioration due to light emitted from a light source while preventing the optical characteristics of the prism from deteriorating with time due to the light deterioration.
- An object is to provide a highly reliable optical head.
- the light source power also acts on the optical recording medium 95.
- the optical path of the laser beam is referred to as the outward path.
- the optical path of the laser beam after being reflected by the optical recording medium 95 is referred to as a return path.
- an aspect of the present invention in one aspect, is an optical head for recording or reproducing a signal on or from an optical recording medium, wherein a light source and light emitted from the light source are transmitted to the optical recording medium.
- the optical head is characterized in that the light separating means includes a first glass, a multilayer film laminated on the first glass, and a second glass fixed to the multilayer film.
- the second glass is adhered and fixed to the multilayer film by an adhesive layer disposed on the multilayer film, and the light separating means also has a first glass force. It is preferable that the emitted light be incident. As a result, since the light emitted from the light source does not pass through the adhesive layer, deterioration due to irradiation with blue light does not occur and the reliability of the optical head is increased. In addition, a special adhesive material that does not deteriorate due to irradiation with blue light is not used, which leads to low cost.
- the second glass may be tightly fixed to the multilayer film. Accordingly, since there is no adhesive layer, deterioration due to irradiation with blue light does not occur, and the reliability of the optical head is improved.
- the nZ4 wave plate includes a first birefringent member and a second birefringent member, and has a crystal axis of the first birefringent member and a crystal axis of the second birefringent member.
- first birefringent member and the second birefringent member are provided at least at a part of the peripheral portion of the first birefringent member and the second birefringent member.
- a spherical aberration correcting unit disposed between the light source and the objective lens on the optical path of the emitted light. This enables stable recording or reproduction even when the substrate thickness of the optical recording medium deviates from the design value.
- the light source preferably emits light having a wavelength of 450 nm or less. This enables high-density information recording and reproduction.
- the multilayer film is preferably formed over the first glass by an evaporation method.
- an optical element is provided between the light source and the objective lens on the optical path of the emitted light, and converts the divergent light into substantially parallel light. It is preferable to be disposed between the light source and the optical element on the optical path of the emitted light. This makes it possible to reduce the size of the optical head.
- an optical head for recording or reproducing a signal on or from an optical recording medium, comprising a light source and an objective lens for condensing light emitted from the light source on the optical recording medium.
- An optical head, wherein the first birefringent member and the second birefringent member are adhered to at least a part of the periphery of the first birefringent member and the second birefringent member. is there.
- an optical recording / reproducing apparatus for recording or reproducing a signal on or from an optical recording medium
- the recording / reproducing apparatus for recording or reproducing a signal on or from an optical recording medium.
- An optical recording and reproducing apparatus comprising an optical head according to an aspect.
- an optical head using a laser light source it is possible to configure so that light does not pass through the adhesive layer of the polarizing beam splitter, which is a light separating means, on the outward path. Does not occur. Therefore, an optical head capable of performing high-density recording with high reliability can be realized.
- the configuration of the present invention can realize a highly reliable optical head.
- the light separating means in the divergent light in which the light density is expected to increase locally. Therefore, an optical head having high reliability and suitable for miniaturization can be realized.
- FIG. 1 is a schematic view showing an example of an optical head according to the present invention.
- FIG. 2 is a configuration diagram of a polarizing beam splitter mounted on the optical head of the present invention.
- FIG. 3 is a schematic view showing another example of the optical head of the present invention.
- FIG. 4 is a configuration diagram showing another example of the polarization beam splitter mounted on the optical head of the present invention.
- FIG. 5 is a configuration diagram of a 1Z4 wavelength plate mounted on the optical head of the present invention.
- FIG. 6 is a plan view showing crystal directions of two birefringent members of a 1Z4 wavelength plate.
- FIG. 7A is a sectional view showing an arrangement position of an adhesive layer of a 1Z4 wavelength plate.
- FIG. 7B is a sectional view showing an arrangement position of an adhesive layer of the 1Z4 wavelength plate.
- FIG. 8 is a schematic view showing another example of the optical head of the present invention.
- FIG. 9 is a cross-sectional view showing an example of a spherical aberration correction unit having a phase change layer.
- FIG. 10 is a diagram showing an example of an electrode pattern of a spherical aberration correction unit having a phase change layer.
- FIG. 11 is a schematic view showing an example of the optical recording / reproducing apparatus of the present invention.
- FIG. 12 is a schematic view showing an example of a conventional optical head.
- Processing circuit 84 Light intensity monitor
- FIG. 1 is a configuration diagram of the optical head according to the first embodiment.
- an optical head includes a light source 1, a light amount attenuating element 2, a polarizing beam splitter 3, a collimator lens 4, a mirror 5, a quarter-wave plate 6, an objective lens 7, a cylindrical lens 9, It has a photodetector 10, a condenser lens 11, and a photodetector 12 for controlling the amount of light from a light source.
- the collimator lens 4 and a one-axis actuator constitute spherical aberration correcting means.
- the polarization beam splitter 3 constitutes a light separating unit.
- the laser light emitted from the light source 1 passes through the light intensity attenuating element 2, enters and reflects on the polarizing beam splitter 3, passes through the collimator lens 4, reflects on the mirror 5, 1Z4 wavelength plate 6, and the objective lens 7 And is incident on the optical recording medium 8.
- the optical path up to this point will be referred to as the outward path.
- a part of the laser light that has entered the optical recording medium 8 is reflected and enters the polarization beam splitter 3 in the reverse direction.
- the light that enters the polarization beam splitter 3 passes through the polarization beam splitter 3, passes through the cylindrical lens 9, and enters the detector 10.
- the optical path from the optical recording medium 8 to the detector 10 is called a return path.
- the polarization beam splitter 3 is configured so that the amount of light that enters the polarization beam splitter 3 from the light source 1 and passes through the polarization beam splitter 3 is several percent to about 10 percent of the total light amount. .
- This light further goes straight upward in the figure, passes through the condenser lens 11, and enters the light source light amount control detector 12.
- the light amount of the light source 1 can be controlled based on the light amount of the light incident on the light source light amount control detector 12.
- the condenser lens 11 and the light source light amount control detector 12 are not essential elements. If the light source light quantity control detector 12 is omitted, the polarization beam splitter 3 should be used so that all the light is reflected by the polarization beam splitter 3 on the outward path.
- the splitter 3 may be configured.
- the light source 1 is composed of, for example, a GaN-based semiconductor laser device (wavelength: 405 nm), and outputs a coherent light for recording and reproduction to the recording layer of the optical recording medium 8.
- the light amount attenuating element 2 is an optical element for reducing the noise of the light source 1 as disclosed in Japanese Patent Application Laid-Open No. 2000-195086, and a light attenuating film (for example, a Cr film) is formed on a part of the glass substrate. ) Is formed, and is movable in the direction of the arrow in the figure.
- the configuration of the polarization beam splitter 3 will be described later in detail, but has a transmittance of 5% and a reflectance of 95% for a certain linearly polarized light (for example, S-polarized light), and is orthogonal to the linearly polarized light. It has a transmittance of 100% for linearly polarized light (P-polarized light).
- the collimator lens 4 is an optical element (lens) that converts divergent light emitted from the light source 1 into substantially parallel light.
- the spherical aberration correcting means is for correcting spherical aberration that occurs when the substrate thickness of the optical recording medium 8 is different from the optimum substrate thickness, and is constituted by a collimator lens 4 and a uniaxial actuator not shown.
- the spherical aberration can be corrected by changing the position of the collimator lens 4 using a negative-axis actuator.
- the mirror 5 is an optical element that reflects incident light and directs it toward the optical recording medium 8, and has a characteristic of reflecting 100% of incident light.
- the configuration of the 1Z4 wavelength plate 6 is an optical element that includes a birefringent material, which will be described in detail later, and has a function of converting linearly polarized light to circularly polarized light.
- the objective lens 7 is a lens that emits light to the recording layer of the optical recording medium 10, and has a numerical aperture (NA) of 0.85.
- the cylindrical lens 9 has a cylindrical incident surface and a rotationally symmetric surface with respect to the lens optical axis.In order to enable detection of a focus error signal by the so-called astigmatism method, the incident light is This gives astigmatism.
- the photodetector 10 receives the light reflected on the recording layer of the optical recording medium 8 and converts the light into an electric signal.
- the condensing lens 11 focuses the light transmitted through the polarization beam splitter 3 to a light source light quantity control photodetector 12, and the light source light quantity control photodetector 12 receives the light transmitted through the polarization beam splitter 3. This converts the light into an electric signal and outputs a signal for detecting the light amount of the light source 1.
- the linearly polarized light emitted from the light source 1 passes through the light attenuating element 2 and almost all of it is Reflects and transmits only a small portion.
- the amount of reflected light and the amount of transmitted light at the polarization beam splitter 3 on the outward path may be about 95 and 5, respectively, assuming that the amount of incident light is 100.
- the reflected light then enters the collimator lens 4 and is converted into one of divergent light, parallel light, and convergent light depending on the position of the collimator lens 4.
- the light whose degree of convergence has been changed enters the mirror 5 and is reflected 100%, so that the traveling direction can be changed toward the optical recording medium 8.
- the circularly polarized light Depending on the degree of divergence of the circularly polarized light incident on the objective lens 7 or the degree of convergence, the circularly polarized light has a spherical aberration, and is condensed in the optical recording medium 8.
- the wavefront aberration generated when the substrate thickness from the surface of the optical recording medium 8 to the recording layer deviates from the optimum substrate thickness is the wavefront generated by the objective lens 7 according to the degree of divergence or the degree of convergence.
- the circularly polarized light reflected from the optical recording medium 8 that is, the light on the return path, passes through the objective lens 7, is incident on the 1Z4 wavelength plate 6, and is orthogonal to the linearly polarized light emitted from the light source 1. It is converted to linearly polarized light having a plane of polarization. All the linearly polarized light converted by the 1Z4 wave plate 6 is reflected by the mirror 5, passes through the collimator lens 4, passes through the polarizing beam splitter 3, that is, enters the cylindrical lens 9 without returning to the light source 1.
- the photodetector 10 outputs a focus error signal indicating a focus state of light on the recording layer of the optical recording medium 8, and outputs a tracking error signal indicating a light irradiation position.
- the focus error signal and the tracking error signal are detected by a known technique, for example, by an astigmatism method and a push-pull method.
- Focus control means (not shown) controls the position of the objective lens 7 in the optical axis direction based on the focus error signal so that light is always focused on the optical recording medium 8 in a focused state.
- the tracking control means controls the position of the objective lens 7 based on the tracking error signal so that the light is focused on a desired track on the optical recording medium 8. Further, information recorded on the optical recording medium 8 can be obtained from the photodetector 10.
- the light that enters from the light source 1 and passes through the polarization beam splitter 3 is condensed by the condenser lens 11 to the light-source-light-quantity control photodetector 12, and The control photodetector 12 outputs an electric signal corresponding to the amount of light emitted from the light source 1.
- FIG. 2 shows a configuration diagram of the polarization beam splitter 3. Referring to FIG.
- the polarizing beam splitter 3 includes a first glass 21, a multilayer film 22, an adhesive layer 23, and a second glass 24.
- the glass material of the first glass 21 and the second glass 24 is, for example, BK7, and the multilayer film 22 is formed by alternately laminating about 20 layers of thin films of silicon dioxide and tantalum pentoxide. It is laminated on the first glass 21 by vapor deposition.
- the adhesive layer 23 is, for example, a UV curable resin.
- the adhesive layer 23 is a resin, it absorbs light having a short wavelength and absorbs a very small amount of light at a blue wavelength (wavelength of 450 nm or less). The resin deteriorates due to its characteristics.
- the optical head described above light is incident from the first glass 21 on the outward path to the polarizing beam splitter 3 configured as described above.
- the adhesive layer 23 gradually deteriorates due to the incidence of blue light. The rate of this deterioration is much faster as the amount of incident light (light density at the adhesive layer) is larger.
- the light on the outward path needs a considerably large amount of light in order to record information on the optical recording medium 8.
- the light reflected by the optical recording medium 8 has a small reflectance of the optical recording medium 8, and therefore the amount of light incident on the polarization beam splitter 3 is very small compared to the amount of light on the outward path.
- the reflectance of the optical recording medium 8 is about 5 to 10%
- the amount of light on the return path is about (1Z20) to (1Z10) of the amount of light on the forward path. Therefore, by configuring the adhesive layer 23 so that light is not transmitted on the outward path and light is transmitted only on the return path, a highly reliable optical head can be configured without deterioration of the adhesive layer 23 constituting the polarization beam splitter 3. .
- the outer shape of the polarizing beam splitter 3 itself can be reduced by disposing the polarizing beam splitter 3 in the diverging light and reducing the size of the light incident on the polarizing beam splitter 3. This is advantageous for downsizing the optical head.
- the light density of the light incident on the polarizing beam splitter 3 increases, so that the structure in which the adhesive layer 23 does not transmit light in the above-described forward path increases the reliability of the optical head. .
- the configuration of the present invention is also advantageous when recording and reproducing a multilayer optical recording medium in which the optical recording medium 8 has many recording layers. When information is recorded on a multilayer optical recording medium having many recording layers, it is necessary to record information on all recording layers.
- the amount of light emitted from 1 is greater than when recording only on a single-layer optical recording medium having only one recording layer. Accordingly, the amount of light incident on the polarization beam splitter 3 itself becomes large, so that a more reliable optical head can be realized by adopting the configuration of the present invention. Similarly, even when the speed of recording and reproducing on the optical recording medium 8 is increased, it is necessary to increase the amount of light irradiating the optical recording medium 8, and the amount of light emitted from the light source 1 increases. With this configuration, a highly reliable optical head can be realized.
- the light source 1 and the polarization beam splitter 3 may be integrated by using a connection mounting member 31.
- the light source 1 and the polarizing beam splitter 3 can be handled as a single body by the connection mounting member 31 which is a connecting portion between the light source 1 and the polarizing beam splitter 3.
- the polarizing beam splitter 3 is configured so that the second glass 24 is tightly fixed to the multilayer film 22 (optical contact) as shown in FIG. 4, deterioration of the adhesive material is not considered. Therefore, a highly reliable optical head can be realized. Furthermore, it is possible to use either reflection or transmission on the outward path.
- FIG. 5 shows a configuration diagram of the 1Z4 wavelength plate 6 used in the optical head of the present invention.
- the 1Z4 wavelength plate 6 has a first birefringent member 41, a second birefringent member 42, and an adhesive layer 43.
- the first and second birefringent members 41 and 42 are made of, for example, quartz.
- a portion between the first birefringent member 41 and the second birefringent member 42 and sandwiched by the adhesive layer 43 Is a void (air layer).
- FIG. 6 is a plan view of the 1Z4 wavelength plate 6 viewed from above. As shown in FIG.
- FIGS. 7A and 7B are examples of arrangement patterns of the adhesive layer 43.
- the adhesive layer 43 may be arranged in a band shape continuous with a predetermined width around the periphery of the 1Z4 wavelength plate 6. Further, as shown in FIG. 7B, the adhesive layers 43 may be discretely arranged at the corners of the 1Z4 wavelength plate 6.
- the adhesive layer 43 is made of, for example, a UV curable resin, and the adhesive layer 43 is provided outside the effective diameter and does not transmit light.
- the dependence of the retardation of the 1Z4 wavelength plate 6 on the incident angle is reduced. This is particularly effective when used in an optical head that performs spherical aberration correction based on the degree of divergence and convergence of light incident on the objective lens 7. Further, since the adhesive layer 43 degraded by blue light is provided at a location where light does not transmit, the adhesive layer 43 does not deteriorate due to blue light. This makes it possible to realize a highly reliable 1Z4 wavelength plate 6 having good incident angle dependence of the 1Z4 wavelength plate 6 and realizing an optical head with good performance and high reliability. Further, by increasing the mounting accuracy of the 1Z4 wavelength plate 6 on the optical head, it becomes possible to use the 1Z4 wavelength plate 6 composed of one crystal. In this case, an optical head with high reliability can be realized because there is no adhesive layer.
- the adhesive layer of the polarizing beam splitter which is the light separating means, is provided on the outward path of the light from the light source. Is configured not to pass through. Thereby, strong light is prevented from being irradiated to the adhesive layer. Since the adhesive layer does not deteriorate, it is possible to realize a light head capable of performing high-density recording with high reliability.
- the light separation means can be arranged in the divergent light where the light density is locally increased and the deterioration of the adhesive layer may be promoted locally, so it is highly reliable and suitable for miniaturization. Optical head can be realized.
- the configuration of the present invention achieves high reliability and realizes an optical head. it can.
- the light separating means is a polarization hologram and this polarization hologram is used.
- the only difference is that there is a photodetector that receives the light diffracted by the gram, and the rest is the same as the first embodiment. Therefore, in the present embodiment, components that are not particularly described are the same as those in the first embodiment, and the components denoted by the same reference numerals as those in the first embodiment are the same as those in the first embodiment unless otherwise described. It has the same function as 1.
- FIG. 8 is a configuration diagram of an optical head according to Embodiment 2 of the present invention.
- the present optical head has a polarization hologram 51, a first photodetector 52, and a second photodetector 53.
- the polarization hologram 51 is disclosed in JP-A-6-27322 and will not be described in detail.
- a predetermined part of a birefringent lithium niobate substrate is proton-exchanged, and the proton-exchange portion is formed.
- This is an optical element that is formed by etching, and has a transmittance of 100% for extraordinary rays and acts as a diffraction grating for ordinary rays.
- the polarization hologram 51 constitutes a light separating means.
- the operation of the optical head thus configured will be described.
- the linearly polarized light emitted from the light source 1 passes through the light quantity attenuating element 2 and is transmitted 100% by the polarization hologram 51.
- This transmitted light enters the collimator lens 4 and is converted into any of divergent light, parallel light, and convergent light depending on the position of the collimator lens 4.
- the light whose degree of convergence has been converted enters the mirror 5, is reflected 100%, and changes its traveling direction toward the optical recording medium 8.
- This reflected light is incident on the quarter-wave plate 6 and is converted from linearly polarized light to circularly polarized light.
- the circularly polarized light is incident on the objective lens 7 and generates spherical aberration according to the degree of divergence or convergence of the incident light. Then, the light is focused on the optical recording medium 8.
- Light having a wavefront aberration that cancels out a wavefront aberration generated when the substrate thickness, which is the distance between the surface of the optical recording medium 8 and the recording layer, is deviated by the optimum substrate thickness force is collected by the objective lens 7. Therefore, on the recording layer of the optical recording medium 8, a light spot having no aberration, that is, a light spot narrowed to the diffraction limit is formed.
- the circularly polarized light reflected from the optical recording medium 8 passes through the objective lens 7, enters the 1Z4 wavelength plate 6, and has a linear direction having a polarization direction orthogonal to the polarization direction of the linearly polarized light emitted from the light source 1.
- Converted to polarized light All the linearly polarized light converted by the 1Z4 wavelength plate 6 is reflected by the mirror 5, passes through the collimator lens 4, and 100% of the transmitted light is diffracted by the polarization hologram 51, and the + 1st-order diffracted light is converted into the first light.
- the light is received by the detector 52, and the first-order diffracted light is received by the second photodetector 53.
- the second photodetectors 52 and 53 output a force error signal indicating the focus state of the light on the optical recording medium 8 and a tracking error signal indicating the irradiation position of the light.
- the focus error signal and the tracking error signal are detected by a known technique, for example, an SSD method and a push-pull method.
- the focus control means controls the position of the objective lens 7 in the optical axis direction based on the focus error signal so that the light is always focused on the optical recording medium 8 in a focused state.
- the tracking control means controls the position of the objective lens 7 based on the tracking error signal so that the light is focused on a desired track on the optical recording medium 8. Further, information recorded on the optical recording medium 8 can be obtained from the first and second photodetectors 52 and 53.
- the 1Z4 wavelength plate 6 has the configuration described in the first embodiment (see FIG. 5), deterioration with respect to blue light does not occur, and a highly reliable optical head can be realized. Become possible
- the 1Z4 wavelength plate used is such that the crystal axes of the two birefringent members are orthogonal in plan view. Degradation of the adhesive layer because it is bonded and the layer of adhesive material (adhesive layer) that bonds the two birefringent members is provided at a place where light does not transmit. There is no. Therefore, it is possible to realize an optical head capable of performing high-density recording with high reliability by using an adhesive material that may cause light deterioration.
- an optical head having spherical aberration correcting means will be described! However, an optical head having no spherical aberration correcting means may be used!
- a method of moving a collimator lens is used as the spherical aberration correcting means.
- a positive lens group and a negative lens group disclosed in Patent Document 1 may be used. No problem.
- a method without using a lens may be adopted as the spherical aberration correcting means.
- a method using a phase change layer disclosed in Japanese Patent Application No. 2001-221927 Japanese Unexamined Patent Application Publication No. 2002-109776 (P2002-109776A)
- the optical elements used in this method are briefly described.
- Figure 9 shows a cross-sectional view of an optical element using liquid crystal as the phase change layer.
- the optical element is substantially parallel to the first substrate 61 and the first substrate 61.
- the liquid crystal 67 disposed between the electrodes 66 (between the voltage application electrode 63 and the counter electrode 64), and the sealing resin 68 disposed between the translucent resin films 65 and 66 so as to surround the liquid crystal 67.
- the first substrate 61 and the second substrate 62 include, for example, glass and have a light-transmitting property.
- the voltage application electrode 63 is an electrode for applying a desired voltage to the liquid crystal 67.
- the voltage application electrode 63 is formed on the main surface inside the first substrate 61 (the liquid crystal 67 side).
- the counter electrode 64 is an electrode for applying a desired voltage to the liquid crystal 67 together with the voltage applying electrode 63.
- the counter electrode 64 is formed on the main surface inside the second substrate 62 (on the liquid crystal 67 side).
- the counter electrode 64 is translucent, and for example, has an ITO force.
- the counter electrode 64 is formed substantially uniformly on at least a portion of the inner main surface of the second substrate 62 which faces the segment electrode.
- the translucent resin films 65 and 66 are alignment films for aligning the liquid crystal 67 in a predetermined direction, and are made of, for example, a polybutyl alcohol film. By subjecting the translucent resin film 65 or 66 to a rubbing treatment, the liquid crystal 67 can be oriented in a predetermined direction. In addition, the liquid crystal 67 functions as a phase change layer that changes the phase of the incident light.
- the liquid crystal 67 is, for example, a nematic liquid crystal color. By changing the voltage difference between the voltage application electrode 63 and the counter electrode 64, the refractive index of the liquid crystal 67 can be changed, and thereby the phase of the incident light can be changed.
- the sealing resin 68 is for sealing the liquid crystal 67, and is made of, for example, epoxy resin.
- the voltage application electrode 63 is constituted by concentric segment electrodes.
- This segment electrode is translucent, and for example, has ITO power.
- a description will be given of the operation of the optical element configured as described above.
- a control voltage is applied from the outside to each of the segment electrodes of the voltage application electrodes of the optical element to give a phase of a power component to light incident on the optical element of the present invention.
- the incident plane wave can be converted into a spherical wave, and the spherical wave enters the objective lens 7, causing spherical aberration.
- the spherical aberration reduces the thickness of the optical recording medium 8.
- the spherical aberration generated when the thickness deviates from the designed base material thickness is corrected.
- a liquid crystal whose refractive index changes according to the voltage is used as the phase change layer, but PLZT whose thickness (volume) changes according to the voltage is PLZT (oxidized lead, lanthanum, oxidized zirconium, oxidized zirconium).
- PLZT oxidized lead, lanthanum, oxidized zirconium, oxidized zirconium
- a transparent crystal having a lobskite structure containing titanium may be used.
- PLZT is a solid, there is no need for a substrate or sealing resin like liquid crystal, so that the optical element can be made thinner.
- the optical element using the phase change layer corrects the aberration caused by the substrate thickness of the optical recording medium 8, so that it is suitable for downsizing the optical head.
- the spherical aberration is corrected using convergent light and divergent light, so that the spherical aberration correction performance does not deteriorate even if the objective lens 7 shifts.
- the prism is applied to the linearly polarized light in the polarization direction of the light emitted from the light source 1 so that the directional light to the objective lens 7 becomes 95% of the light emitted from the light source 1.
- the reflectance is 95% and the transmittance is 5%.
- the transmittance is desirably 50% or less. Further, in order to stably detect the output of the light source 1 without largely losing the light traveling toward the objective lens 7, the transmittance is more preferably 20% or less.
- the 1Z4 wavelength plate 6 is used as the nZ4 wavelength plate, but n may be an odd number.
- the objective lens 7 may be a single lens using a single lens! /, But may be a group lens having NA.
- a finite optical head may be used instead of using the force collimator lens 4 showing an infinite optical head.
- the optical head of the polarization optical system is described in the above embodiment, the optical head may be a non-polarization optical system.
- Embodiment 3 describes an example of the optical recording / reproducing apparatus of the present invention.
- the optical recording / reproducing apparatus according to the third embodiment is an apparatus that performs only recording and reproducing or reproducing of a signal on the optical recording medium 8.
- FIG. 11 schematically shows a configuration of an optical recording / reproducing device 80 according to the third embodiment.
- the optical recording / reproducing device 80 includes an optical head 81, a motor 82, and a processing circuit 83.
- the optical head 81 is as described in the first embodiment.
- the processing circuit 83 includes a light amount monitoring unit 84, a signal processing unit 85, a light amount control unit 86, and an objective lens driving unit 87, and the above-described units included in the processing circuit 83 are connected to each other.
- the optical head 81 is the same as that described in the first embodiment, and a duplicate description will be omitted.
- the operation of the optical recording / reproducing device 80 will be described.
- the motor 82 starts.
- a light amount control unit 86 included in the processing circuit 83 drives the light source 1 to emit light.
- Light emitted from the light source 1 is reflected by the optical recording medium 8 and enters the photodetector 10.
- the photodetector 10 outputs a focus error signal indicating a focused state of light on the optical recording medium 8 and a tracking error signal indicating a light irradiation position to a signal processing unit 85 included in the processing circuit 83.
- the signal processing unit 85 Based on these signals, the signal processing unit 85 outputs information for controlling the objective lens 7 to the objective lens driving unit 87, and the objective lens driving unit 87 controls the objective lens 7 sent from the signal processing unit 85. Based on the information for control, the objective lens is moved by a predetermined amount in a desired direction, and the light emitted from the light source 1 is focused on a desired track on the optical recording medium 8. Further, the signal processing unit 85 reproduces information recorded on the optical recording medium 8 based on a signal output from the photodetector 10.
- a signal output from the light source light amount control photodetector 12 is input to a light amount monitor unit 84 included in the processing circuit 83, and the light amount monitor unit 84 sends information based on this signal to the light amount control unit 86, and The light amount control unit 86 included in the circuit 83 controls the output power of the light source 1 so that the information has a desired value, thereby setting the light amount of the light emitted from the objective lens 7 to a desired value.
- the present optical recording / reproducing device 80 since the optical head of the first embodiment is used as the optical head, the light separating means does not deteriorate with blue light. Therefore, the present optical recording / reproducing device 80 has high reliability, and this reliability does not decrease over time. As described above, the present invention is not limited to the above-described embodiment, but can be applied to other embodiments based on the technical idea of the present invention. .
- the optical recording medium 8 for recording information only by light has been described.
- the same effect can be obtained for an optical recording medium for recording information by light and magnetism. , It doesn't matter.
- the optical recording medium is an optical disk
- the present invention can be applied to an optical information recording / reproducing apparatus that realizes a similar function, such as a card-shaped optical recording medium.
- the optical head and the optical recording / reproducing apparatus according to the present invention are arranged such that light does not pass through the adhesive layer of the polarizing beam splitter, which is a light separating means, on the outward path in an optical head using a light source having a wavelength of 450 nm or less.
- the adhesive layer is not degraded, and is effective as an optical head capable of performing highly reliable high-density recording.
Landscapes
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Head (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006514096A JP4970032B2 (ja) | 2004-06-03 | 2005-05-31 | 光記録再生装置用光ヘッド |
US11/597,996 US7889622B2 (en) | 2004-06-03 | 2005-05-31 | Optical head for optical recorder/reproducer |
US12/983,427 US8184522B2 (en) | 2004-06-03 | 2011-01-03 | Optical head for optical recorder/reproducer |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2004-165267 | 2004-06-03 | ||
JP2004165267 | 2004-06-03 |
Related Child Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/597,996 A-371-Of-International US7889622B2 (en) | 2004-06-03 | 2005-05-31 | Optical head for optical recorder/reproducer |
US12/983,427 Division US8184522B2 (en) | 2004-06-03 | 2011-01-03 | Optical head for optical recorder/reproducer |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2005119669A1 true WO2005119669A1 (ja) | 2005-12-15 |
Family
ID=35463103
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2005/009946 WO2005119669A1 (ja) | 2004-06-03 | 2005-05-31 | 光記録再生装置用光ヘッド |
Country Status (3)
Country | Link |
---|---|
US (2) | US7889622B2 (ja) |
JP (2) | JP4970032B2 (ja) |
WO (1) | WO2005119669A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008001636A1 (fr) * | 2006-06-26 | 2008-01-03 | Asahi Glass Co., Ltd. | composant optique pour faisceau laser |
JP2011232481A (ja) * | 2010-04-27 | 2011-11-17 | Disco Abrasive Syst Ltd | 光学素子 |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9084260B2 (en) | 2005-10-26 | 2015-07-14 | Intel Corporation | Systems for communicating using multiple frequency bands in a wireless network |
US8340071B2 (en) * | 2005-10-26 | 2012-12-25 | Intel Corporation | Systems for communicating using multiple frequency bands in a wireless network |
KR101172364B1 (ko) * | 2006-11-02 | 2012-08-08 | 삼성코닝정밀소재 주식회사 | 질화갈륨 단결정 기판 및 표면 가공방법 |
CN104380160B (zh) * | 2013-05-27 | 2017-12-05 | 华为技术有限公司 | 滤波器、滤波器的制造方法和激光波长监控装置 |
US9678821B2 (en) * | 2015-05-06 | 2017-06-13 | International Business Machines Corporation | Operating a trace procedure for a computer program |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06231506A (ja) * | 1992-12-09 | 1994-08-19 | Omron Corp | 光学的情報記録再生装置及びビームスプリッタ、立ち上げミラー |
JPH08278407A (ja) * | 1995-04-05 | 1996-10-22 | Olympus Optical Co Ltd | ビームスプリッター及び光ピックアップ用ビームスプ リッター |
JPH09245369A (ja) * | 1996-03-11 | 1997-09-19 | Fujitsu Ltd | 光ディスク装置用光学ヘッド |
JPH10112055A (ja) * | 1996-10-02 | 1998-04-28 | Sony Corp | 光学ピックアップ,これを利用した光ディスク・ドライブ及び光磁気ディスク・ドライブ並びに光学ピックアップのレーザビーム整形方法 |
JPH10143904A (ja) * | 1996-11-01 | 1998-05-29 | Matsushita Electric Ind Co Ltd | 光ガイド部材の製造方法 |
JP2001110082A (ja) * | 1999-10-04 | 2001-04-20 | Sony Corp | 光学ピックアップ及び光ディスク装置 |
JP2002092925A (ja) * | 2000-09-13 | 2002-03-29 | Sony Corp | 光学ピックアップ装置 |
JP2002170256A (ja) * | 2000-11-30 | 2002-06-14 | Mitsubishi Electric Corp | 光ヘッド装置、記録及び/又は再生装置並びに記録及び/又は再生方法 |
JP2003187486A (ja) * | 2001-10-12 | 2003-07-04 | Pioneer Electronic Corp | 光ピックアップ |
Family Cites Families (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4627688A (en) * | 1983-07-01 | 1986-12-09 | Sano Kiko Co., Ltd. | Beam splitter |
JPH0810496B2 (ja) | 1986-11-17 | 1996-01-31 | ソニー株式会社 | 光学ヘツドの製造方法 |
JPH02151801A (ja) * | 1988-12-05 | 1990-06-11 | Fujitsu Ltd | 光学部品及びそれを使用した光磁気ディスク用2ビーム型光ヘッド |
EP0601862A1 (en) | 1992-12-09 | 1994-06-15 | Omron Corporation | An optical device formed of multiple film layers |
JPH0727906A (ja) * | 1993-07-09 | 1995-01-31 | Omron Corp | ビームスプリッタ及びこれを用いた光学的情報記録再生装置 |
US6049518A (en) * | 1995-08-31 | 2000-04-11 | Sanyo Electric Co., Ltd. | Optical disc recording/reproducing apparatus recording/reproducing information to/from optical discs according to different standards |
JP3062099B2 (ja) * | 1996-02-06 | 2000-07-10 | 日本電気株式会社 | 光ヘッド装置 |
KR100449458B1 (ko) * | 1996-07-31 | 2004-09-21 | 도또리 상요 덴기 가부시끼가이샤 | 광 디스크 장치 |
DE69722951T2 (de) * | 1996-10-31 | 2004-05-19 | Sanyo Electric Co., Ltd., Moriguchi | Optische abtastvorrichtung |
JPH1164630A (ja) * | 1997-08-21 | 1999-03-05 | Toyo Commun Equip Co Ltd | 偏光ビームスプリッタ |
JPH1186317A (ja) * | 1997-09-12 | 1999-03-30 | Toshiba Corp | 光ピックアップ装置 |
JPH11110773A (ja) | 1997-10-01 | 1999-04-23 | Matsushita Electric Ind Co Ltd | 光ピックアップ |
JP2000131603A (ja) | 1998-10-22 | 2000-05-12 | Sony Corp | 光学ヘッド及び記録再生装置 |
JP4488482B2 (ja) | 1999-01-22 | 2010-06-23 | コニカミノルタホールディングス株式会社 | 光ピックアップ装置 |
ATE216119T1 (de) * | 1999-01-22 | 2002-04-15 | Konishiroku Photo Ind | Optische abtastvorrichtung und verfahren zur informationsaufzeichnung und informationswiedergabe |
US6411587B1 (en) * | 1999-10-08 | 2002-06-25 | Konica Corporation | Optical pickup optical system, optical pickup apparatus, coupling optical system, coupling optical system lens and recording/reproduction apparatus |
EP1102250A3 (en) * | 1999-11-17 | 2003-03-26 | Konica Corporation | Optical pickup apparatus and objective lens |
DE60227854D1 (de) * | 2001-10-01 | 2008-09-04 | Sony Corp | Polarisationsselektives Prisma für einen Projektor |
JP4046580B2 (ja) * | 2002-09-06 | 2008-02-13 | 三洋電機株式会社 | 光ピックアップ装置 |
JP4464830B2 (ja) * | 2002-12-03 | 2010-05-19 | パナソニック株式会社 | 光ヘッド装置、光記録装置及び光記録方法 |
US7193955B2 (en) * | 2003-03-20 | 2007-03-20 | Matsushita Electric Industrial Co., Ltd. | Optical head device and optical information reproducing device |
JP2003331459A (ja) | 2003-05-01 | 2003-11-21 | Ricoh Co Ltd | 光ヘッド |
KR100940205B1 (ko) * | 2003-07-01 | 2010-02-10 | 삼성전자주식회사 | 호환형 광픽업 |
-
2005
- 2005-05-31 US US11/597,996 patent/US7889622B2/en active Active
- 2005-05-31 JP JP2006514096A patent/JP4970032B2/ja active Active
- 2005-05-31 WO PCT/JP2005/009946 patent/WO2005119669A1/ja active Application Filing
-
2010
- 2010-12-24 JP JP2010287045A patent/JP5042352B2/ja active Active
-
2011
- 2011-01-03 US US12/983,427 patent/US8184522B2/en active Active
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06231506A (ja) * | 1992-12-09 | 1994-08-19 | Omron Corp | 光学的情報記録再生装置及びビームスプリッタ、立ち上げミラー |
JPH08278407A (ja) * | 1995-04-05 | 1996-10-22 | Olympus Optical Co Ltd | ビームスプリッター及び光ピックアップ用ビームスプ リッター |
JPH09245369A (ja) * | 1996-03-11 | 1997-09-19 | Fujitsu Ltd | 光ディスク装置用光学ヘッド |
JPH10112055A (ja) * | 1996-10-02 | 1998-04-28 | Sony Corp | 光学ピックアップ,これを利用した光ディスク・ドライブ及び光磁気ディスク・ドライブ並びに光学ピックアップのレーザビーム整形方法 |
JPH10143904A (ja) * | 1996-11-01 | 1998-05-29 | Matsushita Electric Ind Co Ltd | 光ガイド部材の製造方法 |
JP2001110082A (ja) * | 1999-10-04 | 2001-04-20 | Sony Corp | 光学ピックアップ及び光ディスク装置 |
JP2002092925A (ja) * | 2000-09-13 | 2002-03-29 | Sony Corp | 光学ピックアップ装置 |
JP2002170256A (ja) * | 2000-11-30 | 2002-06-14 | Mitsubishi Electric Corp | 光ヘッド装置、記録及び/又は再生装置並びに記録及び/又は再生方法 |
JP2003187486A (ja) * | 2001-10-12 | 2003-07-04 | Pioneer Electronic Corp | 光ピックアップ |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008001636A1 (fr) * | 2006-06-26 | 2008-01-03 | Asahi Glass Co., Ltd. | composant optique pour faisceau laser |
JP2011232481A (ja) * | 2010-04-27 | 2011-11-17 | Disco Abrasive Syst Ltd | 光学素子 |
Also Published As
Publication number | Publication date |
---|---|
US20080013414A1 (en) | 2008-01-17 |
US20110096645A1 (en) | 2011-04-28 |
JP2011060422A (ja) | 2011-03-24 |
JP4970032B2 (ja) | 2012-07-04 |
JPWO2005119669A1 (ja) | 2008-04-03 |
US8184522B2 (en) | 2012-05-22 |
JP5042352B2 (ja) | 2012-10-03 |
US7889622B2 (en) | 2011-02-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7352664B2 (en) | Optical element, optical head, optical recording reproducing apparatus and optical recording/reproducing method | |
JP5042352B2 (ja) | 光記録再生装置用光ヘッド | |
KR100483129B1 (ko) | 광헤드및광디스크장치 | |
JP2004355790A (ja) | ホログラム結合体およびその製造方法、ホログラムレーザユニットならびに光ピックアップ装置 | |
WO2005124749A1 (ja) | 光情報装置及び光情報装置の制御方法 | |
JP4733868B2 (ja) | 光ヘッドと光記録再生装置 | |
KR100782813B1 (ko) | 능동형 보정소자 및 이를 채용한 호환형 광픽업 및 광 기록및/또는 재생기기 | |
JP4792910B2 (ja) | 液晶デバイスおよび光ピックアップ | |
JP2007305254A (ja) | 光ピックアップ及び光ディスク装置。 | |
JP5424329B2 (ja) | 光路切替素子、光路切替装置、光ヘッド装置、及び光学式情報記録再生装置 | |
JPH10222856A (ja) | 光学式情報記録再生装置 | |
JP2009009617A (ja) | 光ヘッドと光情報装置とコンピュータと映像記録再生装置と映像再生装置とサーバーとカーナビゲーションシステム | |
JP4568653B2 (ja) | 光ピックアップおよび光情報処理装置 | |
JP3570139B2 (ja) | 光ピックアップ | |
JP2004296082A (ja) | 光記録媒体 | |
JP2002352470A (ja) | 光記録媒体 | |
JP2011227944A (ja) | 光ヘッド装置 | |
JP4041114B2 (ja) | 光学ピックアップ装置 | |
JPH10228664A (ja) | 光ピックアップ装置 | |
JP2005141839A (ja) | 光ヘッド装置 | |
JP2009009615A (ja) | 光ヘッドと光ヘッドの組立方法と光記録再生装置とコンピュータと映像記録再生装置と映像再生装置とサーバーとカーナビゲーションシステム | |
JP2005332519A (ja) | 液晶収差補正素子・光ピックアップ装置および光ディスクドライブ装置 | |
JP2008112576A (ja) | 光記録再生装置、光ヘッド、光記録再生方法及び処理回路 | |
WO2013183439A1 (ja) | 光ピックアップ装置 | |
JP2001126294A (ja) | 光学素子および光ヘッド装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KM KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
DPEN | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed from 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2006514096 Country of ref document: JP |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWW | Wipo information: withdrawn in national office |
Country of ref document: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 11597996 Country of ref document: US |
|
122 | Ep: pct application non-entry in european phase | ||
WWP | Wipo information: published in national office |
Ref document number: 11597996 Country of ref document: US |