[go: up one dir, main page]

WO2006031643A1 - Element optique de diffraction, systeme optique comportant cet element et procedes associes - Google Patents

Element optique de diffraction, systeme optique comportant cet element et procedes associes Download PDF

Info

Publication number
WO2006031643A1
WO2006031643A1 PCT/US2005/032125 US2005032125W WO2006031643A1 WO 2006031643 A1 WO2006031643 A1 WO 2006031643A1 US 2005032125 W US2005032125 W US 2005032125W WO 2006031643 A1 WO2006031643 A1 WO 2006031643A1
Authority
WO
WIPO (PCT)
Prior art keywords
diffractive
doe
wavelength
corrector
features
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2005/032125
Other languages
English (en)
Inventor
Michael R. Feldman
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
DigitalOptics Corp East
Original Assignee
Tessera North America Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US10/949,807 external-priority patent/US7773143B2/en
Application filed by Tessera North America Inc filed Critical Tessera North America Inc
Publication of WO2006031643A1 publication Critical patent/WO2006031643A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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
    • G11B7/135—Means for guiding the beam from the source to the record carrier or from the record carrier to the detector
    • G11B7/1353—Diffractive elements, e.g. holograms or gratings
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/18—Diffraction gratings
    • G02B5/1866—Transmission gratings characterised by their structure, e.g. step profile, contours of substrate or grooves, pitch variations, materials
    • G02B5/1871—Transmissive phase gratings
    • 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
    • G11B7/125—Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for controlling the size or intensity of optical spots or optical traces
    • G11B7/127—Lasers; Multiple laser arrays
    • G11B7/1275—Two or more lasers having different wavelengths
    • 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
    • G11B2007/0003—Recording, reproducing or erasing systems characterised by the structure or type of the carrier
    • G11B2007/0006—Recording, reproducing or erasing systems characterised by the structure or type of the carrier adapted for scanning different types of carrier, e.g. CD & DVD

Definitions

  • the present invention is directed to a diffractive optical element (DOE).
  • DOE diffractive optical element
  • FIGS. 5A-5C illustrate the different requirements for the three different systems.
  • FIG. 5A illustrates a schematic side view of the blue-ray system
  • FIG. 5B illustrates a schematic side view of the blue-ray system
  • FIG. 5C illustrates a schematic side view of the blue-ray system.
  • cover portions of the media are shown for ease of illustration, so the beam will be focused beyond these cover portions.
  • the different systems use the same objective lens 50 and the same DOE corrector 58, while requiring different numerical apertures (NAs) and having different media thicknesses. To get the NAs correct while maintaining reasonable working distances and minimizing differences in the focal lengths, the beam diameter may be changed across the systems.
  • NAs numerical apertures
  • the blue-ray system has a beam 51 that is roughly 3 mm which is to be focused onto a blue-ray media 52
  • the DVD system has a beam 53 that is roughly 2.5 mm which is to be focused onto a DVD media 54
  • CD system has a beam 55 that is roughly 2 mm which is to be focused onto a CD media 56.
  • DOE correctors do not provide very high diffraction efficiency for all three wavelengths, especially when the input beams are collimated, are sensitive to temperature changes and are difficult to manufacture.
  • SUMMARY OF THE INVENTION [0005] The present invention is therefore directed to a diffractive optical element
  • DOE DOE
  • DOE corrector an optical system using the DOE corrector and methods of making the DOE, DOE corrector and system, which substantially overcome one or more of the problems due to the limitations and disadvantages of the related art.
  • DOE DOE
  • DOE corrector having multiple levels.
  • DOE corrector having which is relatively insensitive to changes in temperature.
  • FIG. 1A is a schematic side view of a DOE corrector in accordance with a first embodiment of the present invention
  • FIG. 1 B is a schematic side view of a DOE corrector in accordance with a second embodiment of the present invention
  • FIG. 1C is a schematic side view of a DOE corrector in accordance with a third embodiment of the present invention
  • FIG. 1 D is a schematic side view of a DOE corrector in accordance with a fourth embodiment of the present invention.
  • FIG. 2 is a plot of the structure of the diffractive element for red light on the fused silica side, from the center of the element outwards;
  • FIG. 3 is a schematic side view of a DOE corrector of the present invention aligned with a lens to be corrected according to an embodiment of the present invention
  • FIG. 4 is a schematic perspective view of a DOE corrector of the present invention aligned with a lens to be corrected according to another embodiment of the present invention.
  • FIG. 5A-5C are schematic side views illustrating a problem to be solved by the present invention.
  • a DOE corrector 3 has first diffractive element 2 on a single surface 1 thereof.
  • the diffractive element 2 includes a first phase function providing a high first order efficiency for red light and a second phase function providing a high first order efficiency for IR light, while providing high zeroth order efficiency for blue light.
  • a thick DOE needs to be used. For example, to make phase levels that are multiples of 2 ⁇ for the blue wavelength, the phase delay for a transmission DOE is given by:
  • n is the index of refraction of the DOE for blue light
  • d is the thickness of the DOE
  • lambda is the wavelength of the blue light.
  • phase levels would be determined from integer multiples M of D that do not effect the blue light. For most materials this results in very thick elements with relatively low efficiency, especially in the IR, e.g., less than 50%.
  • the first embodiment is limited to a binary
  • DOE for IR light, unless a very thick diffractive structure, e.g., much thicker than 65 microns, is used.
  • Such a binary DOE has very low efficiency, roughly 40%, compared with roughly 80% for a four-level DOE.
  • Thicker DOEs are a problem, as they are more difficult to fabricate, and generally don't perform as well due to shadowing. Shadowing is due to the relative aspect ratios of the etch depth and the period. For manufacturability, this aspect ratio should be less than about two, and the etch depth should less than about 35 microns.
  • fused silica for DOE correctors may not work well for beams at 405nm and 785nm, since the phase delay ratio of these wavelengths in fused silica if very close to 1 :2, making the only manufacturable harmonic structure practical a binary lens, which is very inefficient.
  • This structure in fused silica alone may provide sufficient diffraction efficiencies for certain applications. For example, a minimum diffraction efficiency for only reading from a media may be about 25%, while a minimum diffraction efficiency for writing to a media may be about 60-70%.
  • high diffraction efficiency means a minimum diffraction efficiency required for the desired use.
  • phase levels for a first phase function at a first wavelength are selected that correspond to a zero phase delay (modulo 2 ⁇ ) or about zero phase delay for the other two wavelengths, e.g., 407 nm and 785 nm.
  • phase levels for a second phase function at a second wavelength are chosen to correspond to zero for the other two wavelengths, e.g., 407 nm and 650 nm.
  • phase levels are provided in a material having no dispersion and a refractive index of 1.46.
  • For simplification, consider only solutions MD for blue light. In designing the second phase function and restricting the multiple of D to M ⁇ IO, and then looking for values of M within this range where the phase angle for the red light is less than ⁇ 20°, then there are five values for M which satisfy this condition. However, these phase levels also need to provide phase angles close to 0°, 90°, 180° and 270° for a four phase level diffractive for the IR light. Only three of the five values are within ⁇ 20° of these target values. A diffractive other than a binary diffractive would thus need to be made with more than a thickness of M 40 at 407 nm, i.e., more than 35 microns thick.
  • the refractive index of fused silica actually decreases as wavelength increases, i.e., positive dispersion, the refractive index of fused silica is actually 1.470 at 405 nm, 1.457 at 650 nm, and 1.453 at 785 nm. This dispersion results in the blue and IR light becoming even more closely harmonic, as can be seen with reference to the following phase delay ratio of Equation (3):
  • phase delay ratio 1.93, while in fused silica, it becomes 2.01.
  • M is selected to be an integer for the blue light
  • phase values for the IR light will all be within ⁇ 10° of either 0° or 180° for all values of M ⁇ 75, resulting in a DOE having a thickness of at least 65 microns to realize even a four level DOE.
  • a DOE corrector 5 in accordance with the second embodiment of the present invention is shown in FIG. 1 B.
  • the DOE corrector 5 includes a substrate 10 having a first diffractive 12 in a first material providing a harmonic phase delay, i.e., the phase delay ratio of equation 3 is approximately an integer, and a second diffractive 14 in a second material providing a non-harmonic phase delay, i.e., so that the first and third wavelengths are treated substantially differently.
  • the substrate 10 may be a harmonic phase delay material, such as fused silica, into which the first diffractive 12 is etched, and then a non-harmonic phase delay material 16 may be provided on an opposite side of the substrate 10 in which the second diffractive 14 is formed.
  • a non-harmonic phase delay material 16 may be provided on an opposite side of the substrate 10 in which the second diffractive 14 is formed.
  • an embossable material such as a polymer, may be used as the non-harmonic phase delay material 16, and the second diffractive 14 may be stamped into the embossable material.
  • the etch depths in the diffractive are set to be 2 ⁇ multiples for that wavelength, so the diffractive structure essentially does not effect light at that wavelength, i.e., the phase delay will be negligible.
  • the diffractive etch depths are limited to be 2 ⁇ r multiples of the IR light, rather than the blue light, since the IR light is practically a harmonic of the blue light. In other words, the diffractive etch depths are limited to be 4 ⁇ multiples of the blue light.
  • the target (modulo 2 ⁇ ) phase values for the red light are given by:
  • the second diffractive element is designed to provide a high efficiency first order for the IR light.
  • the second diffractive element is designed by selecting a maximum phase error for each wavelength not to be effected by the second diffractive element, here the blue and red light. Then, all levels that are equal to integer multiples of 2 ⁇ , within the maximum phase error, are determined for the blue light.
  • the maximum phase error for each wavelength may be the same. Then those levels that are not also within a maximum phase error of 2 ⁇ for the red light are eliminated. Finally, the remaining levels are then selected in accordance with equation (1 ) for the IR light.
  • the non-harmonic phase delay material may be Ti ⁇ 2 , SU-8, ultra-violet (UV) curable polymers, thermally curable polymers, or semi-fluorinated polymer, such as Perfluorocyclobutane (PFCB) polymer, e.g., BPVE polymer from Tetramer Technologies, having an appropriate dispersion.
  • PFCB Perfluorocyclobutane
  • etch depths that are not exact 2 ⁇ multiples of blue light, e.g., within a 20 degree error as for the IR.
  • a practical diffractive optical element may be formed in the fused silica having between four and twelve levels.
  • the maximum etch depth of the thin film, e.g., a UV curable polymer noted above is fifteen microns, a diffractive optical element formed therein may have between four and eight levels. Again, the limitations on the etch depth is due to shadowing and vector diffraction effects due to the aspect ratio.
  • FIG. 2 A specific example of a structure for the first diffractive element according to the second embodiment is shown in FIG. 2. As can be seen therein, the period and etch depth across the diffractive element may be varied.
  • a third embodiment of the present invention is shown in FIG. 1C.
  • a DOE corrector 30 includes a first diffractive element 32 on a surface of a substrate 31 and a second diffractive element 34 on a surface of a non-harmonic phase delay material 36 on an opposite side of the substrate 31 from the first diffractive element.
  • the non-harmonic phase delay material 36 may be any of the polymers noted above.
  • the two diffractive elements 32 and 34 are used to create a single phase function for at least one of the wavelengths, as opposed to the dedicated phase functions of diffractive elements 12 and 14 in the second embodiment.
  • the low dispersion material e.g., the fused silica
  • the fused silica may be used to diffract one of the harmonic wavelengths, partially diffract another wavelength and transmit the other harmonic wavelength.
  • Examples of available phase levels in fused silica are provided below in the following Table. All phase delays are given in waves (modulo 2pi) and the phase delay is 0 or 1 wave (2pi) for 405 nm.
  • This resultant effective diffractive is equivalent to a five level, evenly spaced diffractive for 660 nm and a binary diffractive for 785 nm.
  • the scalar diffraction efficiency for the element only in fused silica is 100% for 405 nm, 87% for 660 nm and 40% for 785 nm.
  • This low efficiency for the IR light is further compounded due to the presence of 40% in the -1 order as well.
  • Light outside a desired diffraction order, here +1 for 660 nm and 785 nm, and 0 th for 405 nm, should be minimized as well as maximizing the light in the desired diffraction order.
  • the polymer side may have two levels, e.g., 0 and 0.25 waves or three levels, e.g., evenly spaced between 0 and 0.5 wave, i.e., 0, 1/6, and 1/3 waves. This would then provide a resultant effective diffractive for 785 nm having a total of four levels or six levels, respectively.
  • the polymer may be made much thinner.
  • the fused silica part is 8.7 microns thick and the polymer part is over 16 microns thick. This resulted in a combined diffraction efficiency for the part to be 94%, 81 % and 69% for 405 nm, 660 nm and 785 nm, respectively.
  • the fused silica part is 7.78 microns and the polymer part was reduced to binary structure of 4.98 microns, which provides a phase value of approximately zero radians for both 405 nm and 660 nm, and a phase delay of approximately 0.25 waves for 785 nm.
  • the resultant combined diffraction efficiency is then 97%, 85% and 80% for 405 nm, 660 nm and 785 nm, respectively.
  • the resultant combined diffraction efficiency is then 97%, 85% and 88% for 405 nm, 660 nm and 785 nm, respectively.
  • both diffractive elements 32 and 34 in the third embodiment diffract a common wavelength
  • the alignment between the two elements is more critical than in the second embodiment, and the spacing between the diffractive elements must be tightly controlled.
  • FIG. 1 D One manner of achieving this control is shown in FIG. 1 D.
  • a DOE corrector 40 includes a first diffractive element 42 on a first substrate 41 and a second diffractive element 44 on a layer 46 on a second substrate 43.
  • a securing element 45 may secure the first and second substrates 42, 43 together.
  • the first and second diffractive elements are on opposing surfaces of different substrates which have been secured together, rather than on opposite sides of the same substrate as in the second and third embodiments. This allows the diffractive elements to be made closer together.
  • the spacing between the two diffractive elements is particularly important when the two surfaces create a single phase function, e.g., in accordance with the third embodiment, as opposed to two independent phase functions.
  • the two diffractive elements need to be close enough so that there are no significant diffractive effects between them.
  • the alignment may be realized in numerous manners, e.g., wafer-to-wafer bonding, injection molding the polymer part including alignment features to mate with corresponding features on the fused silica part, insert injection mold the polymer part around the fused silica part, or replicate the polymer part directly on top of the fused silica part.
  • the alignment and spacing is not very sensitive, and the separate substrates do not even need to be immediately adjacent.
  • a further alternative using two substrates would include securing a surface of a wafer having the first diffractive element to a second wafer, thinning the second wafer to a desired thickness, e.g., 20 microns, and depositing the second material in which the second diffractive element is to be formed.
  • scattering regions can be created to scatter light at 785 nm or at both 785 and 660 nm, to reduce the effective aperture for these wavelengths.
  • the desired phase function for 785 nm becomes a binary grating with at a radius larger than a desired effective aperture for 785 nm at a high enough spatial frequency to cause light at 785 nm to be diffracted in to a region large enough to significantly reduce the signal power at the disk.
  • an anti-reflective coating may be provided on the DOE corrector, the input beams may be collimated and the DOE corrector may also correct for aberrations and dispersion.
  • FIG. 3 illustrates the DOE corrector 5 of FIG. 1 B aligned with a lens 24 to be corrected, when the lens 24 is roughly a sphere.
  • a substrate 28 is patterned and etched to form a hole 22 therein.
  • This hole 22 receives the lens 24, which may be secured in the hole by using an adhesive 26, e.g., solder.
  • the lens 24 may be polished to flatten a surface 25 thereof to be about even with a surface of the substrate 28, as shown in FIG. 3, or may remain in its original form.
  • the substrate 28 is then aligned with the DOE corrector 5 and these components may be secured together, e.g., using a bonding material 21 , as shown in FIG. 3.
  • the DOE corrector 5 and the substrate 28 may be aligned and secured as a plurality of elements, e.g., on a wafer level. Then, a resultant optical element 20 may be realized by separating the wafer containing multiple resultant optical elements 20 along lines 138.
  • FIG. 4 illustrates the DOE corrector 5 of FIG. 1 B aligned with a lens 48 to be corrected, when the lens 48 is provided on a surface of a substrate 49.
  • the DOE corrector 5 and the substrate 49 may be die bonded together on a multiple scale or individually.
  • a DOE corrector for use with three wavelengths may be provided.
  • the DOE corrector may be formed by providing a first diffractive element in a harmonic phase delay material and a second diffractive element in a non-harmonic phase delay material.
  • the phase delay ratio may be less than 1.95 or greater than 2.05 in the non- harmonic phase delay material, and within these bounds for the harmonic phase delay material.
  • the DOE corrector may face either direction.
  • both the harmonic and non-harmonic phase delay materials may be provided on opposite sides of a substrate, or the substrate may be the non-harmonic phase delay material.
  • the diffraction efficiency for a desired order is greater than about 70%.
  • a diffractive optical element having two diffractive surfaces providing a single phase function may be realized in two materials having different dispersions, such that the combined efficiency is greater than either efficiency alone.
  • Embodiments of the present invention have been disclosed herein and, although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. For example, while a spherical lens has been illustrated, other shapes, using different alignment mechanisms, may be used. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.

Landscapes

  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • General Physics & Mathematics (AREA)
  • Diffracting Gratings Or Hologram Optical Elements (AREA)

Abstract

L'invention concerne un élément optique de diffraction (DOE) à utiliser avec une première, une deuxième et une troisième longueur d'onde. Cet élément comprend un premier élément de diffraction situé sur une première surface et constitué d'un premier matériau, ce premier élément de diffraction comportant des premières caractéristiques de diffraction pour la troisième longueur d'onde, toutes ces premières caractéristiques ayant un creux de gravure d'environ ?1/(n1-1) ou des multiples de nombres entiers de ces dernières, où ?1 représente la première longueur d'onde et n1 représente l'indice de réfraction de la première matière de la première longueur d'onde, les premières caractéristiques donnant une première fonction phase pour la deuxième longueur d'onde ayant une efficacité élevée de premier ordre et une deuxième fonction de phase pour la troisième longueur d'onde ayant une efficacité élevée de premier ordre. Un élément optique de diffraction comprend un premier élément de diffraction constitué d'une première matière et un deuxième élément de diffraction constitué d'une deuxième matière. La deuxième matière a une dispersion différente de celle de la première matière, le premier et le deuxième élément de diffraction offrant une fonction phase combinée pour une longueur d'onde de conception ayant une efficacité de diffraction supérieure à celle offerte par le premier et le deuxième élément de diffraction respectivement seuls.
PCT/US2005/032125 2004-09-10 2005-09-12 Element optique de diffraction, systeme optique comportant cet element et procedes associes Ceased WO2006031643A1 (fr)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
US60837504P 2004-09-10 2004-09-10
US60/608,375 2004-09-10
US10/949,807 2004-09-27
US10/949,807 US7773143B2 (en) 2004-04-08 2004-09-27 Thin color camera having sub-pixel resolution
US65689105P 2005-03-01 2005-03-01
US60/656,891 2005-03-01
US69754205P 2005-07-11 2005-07-11
US60/697,542 2005-07-11

Publications (1)

Publication Number Publication Date
WO2006031643A1 true WO2006031643A1 (fr) 2006-03-23

Family

ID=35517277

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2005/032125 Ceased WO2006031643A1 (fr) 2004-09-10 2005-09-12 Element optique de diffraction, systeme optique comportant cet element et procedes associes

Country Status (1)

Country Link
WO (1) WO2006031643A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006127076A1 (fr) * 2005-03-01 2006-11-30 Digital Optics Corporation Dispositif de correction chromatique a element optique diffractif, systeme optique comportant un tel correcteur et procedes associes
US9046638B2 (en) 2006-06-23 2015-06-02 Toray Industries, Inc. White reflection film

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0747893A2 (fr) * 1995-06-05 1996-12-11 Nec Corporation Tête optique pour différents types de disques
EP1148355A1 (fr) * 2000-04-20 2001-10-24 Canon Kabushiki Kaisha Appareil de prise d'image ayant un élément optique diffractif
US20030067686A1 (en) * 2001-10-05 2003-04-10 Matsushita Electric Industrial Co., Ltd. Diffractive optical element and optical head using the same
WO2003075267A1 (fr) * 2002-03-06 2003-09-12 Matsushita Electric Industrial Co., Ltd. Mecanisme de tete optique et dispositif de lecture d'informations optiques utilisant un tel mecanisme, lecteur de disque optique, systeme de navigation automobile, enregistreur de disque optique et serveur de disque optique utilisant ce dispositif de lecture d'informations optiques
WO2003091764A1 (fr) * 2002-04-18 2003-11-06 Matsushita Electric Industrial Co., Ltd. Element optique, tete optique, dispositif d'enregistrement/reproduction d'informations optiques, ordinateur, dispositif d'enregistrement video, dispositif de reproduction video, serveur et systeme de navigation de vehicule

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0747893A2 (fr) * 1995-06-05 1996-12-11 Nec Corporation Tête optique pour différents types de disques
EP1148355A1 (fr) * 2000-04-20 2001-10-24 Canon Kabushiki Kaisha Appareil de prise d'image ayant un élément optique diffractif
US20030067686A1 (en) * 2001-10-05 2003-04-10 Matsushita Electric Industrial Co., Ltd. Diffractive optical element and optical head using the same
WO2003075267A1 (fr) * 2002-03-06 2003-09-12 Matsushita Electric Industrial Co., Ltd. Mecanisme de tete optique et dispositif de lecture d'informations optiques utilisant un tel mecanisme, lecteur de disque optique, systeme de navigation automobile, enregistreur de disque optique et serveur de disque optique utilisant ce dispositif de lecture d'informations optiques
US20050152258A1 (en) * 2002-03-06 2005-07-14 Matsushita Electric Industrial Co., Ltd. Optical head device and optical information device using this and computer optical disk player car navigation syhstem optical disy recorder and optical disk server using this optical information device
WO2003091764A1 (fr) * 2002-04-18 2003-11-06 Matsushita Electric Industrial Co., Ltd. Element optique, tete optique, dispositif d'enregistrement/reproduction d'informations optiques, ordinateur, dispositif d'enregistrement video, dispositif de reproduction video, serveur et systeme de navigation de vehicule
EP1500956A1 (fr) * 2002-04-18 2005-01-26 Matsushita Electric Industrial Co., Ltd. Element optique, tete optique, dispositif d'enregistrement/reproduction d'informations optiques, ordinateur, dispositif d'enregistrement video, dispositif de reproduction video, serveur et systeme de navigation de vehicule

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006127076A1 (fr) * 2005-03-01 2006-11-30 Digital Optics Corporation Dispositif de correction chromatique a element optique diffractif, systeme optique comportant un tel correcteur et procedes associes
US9046638B2 (en) 2006-06-23 2015-06-02 Toray Industries, Inc. White reflection film

Similar Documents

Publication Publication Date Title
EP1126291B1 (fr) Dephaseur et tete optique montee en association avec ledit dephaseur
JP4341332B2 (ja) 光ヘッド装置
KR101055342B1 (ko) 광 픽업 및 광학 정보 처리 장치
WO2005076265A1 (fr) Element d’objectif a cristaux liquides et dispositif a tete optique
US5566024A (en) Beam separation control and beam splitting by single blazed binary diffraction optical element
US5537252A (en) Double blazed binary diffraction optical element beam splitter
JP2006073042A (ja) 回折素子および光ヘッド装置
US7729051B2 (en) Method of making an optical system
US7548359B2 (en) Double-wavelength light source unit and optical head device having four diffraction gratings
WO2006031643A1 (fr) Element optique de diffraction, systeme optique comportant cet element et procedes associes
JP4518009B2 (ja) ３波長用回折素子、位相板付３波長用回折素子および光ヘッド装置
US7158303B2 (en) Chromatic diffractive optical element corrector, optical system including the same and associated methods
JP4561080B2 (ja) 回折素子および光ヘッド装置
JP2012009096A (ja) 波長選択波長板、波長選択回折素子および光ヘッド装置
JP2003185819A (ja) 回折素子および光ヘッド装置
EP1562186A1 (fr) Unite de source lumineuse a longueur d'onde double et dispositif de tete optique
US8154802B2 (en) Chromatic diffractive optical element corrector, optical system including the same and associated methods
WO2006127076A1 (fr) Dispositif de correction chromatique a element optique diffractif, systeme optique comportant un tel correcteur et procedes associes
EP1873770B1 (fr) Dispositif de détection optique
JP2011233208A (ja) 波長選択波長板、波長選択回折素子および光ヘッド装置
JP2000155974A (ja) 位相制御素子及びこれを用いた光ヘッド装置
JP2000348366A (ja) 光ヘッド装置
JP2013077374A (ja) 回折素子および光ヘッド装置
JP2001126294A (ja) 光学素子および光ヘッド装置
JP2010153039A (ja) ３波長用回折素子、位相板付３波長用回折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 LV 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
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase