WO2006024998A2 - A laser projection system - Google Patents

A laser projection system Download PDF

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Publication number
WO2006024998A2
WO2006024998A2 PCT/IB2005/052787 IB2005052787W WO2006024998A2 WO 2006024998 A2 WO2006024998 A2 WO 2006024998A2 IB 2005052787 W IB2005052787 W IB 2005052787W WO 2006024998 A2 WO2006024998 A2 WO 2006024998A2
Authority
WO
WIPO (PCT)
Prior art keywords
cell
laser
projection system
laser beam
fluids
Prior art date
Application number
PCT/IB2005/052787
Other languages
French (fr)
Other versions
WO2006024998A3 (en
Inventor
Renatus H. M. Sanders
Johannus W. Weekamp
Original Assignee
Koninklijke Philips Electronics N.V.
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
Application filed by Koninklijke Philips Electronics N.V. filed Critical Koninklijke Philips Electronics N.V.
Priority to EP05781102A priority Critical patent/EP1787167B1/en
Priority to US11/573,915 priority patent/US7775670B2/en
Priority to DE602005005836T priority patent/DE602005005836T2/en
Priority to JP2007529095A priority patent/JP4658127B2/en
Publication of WO2006024998A2 publication Critical patent/WO2006024998A2/en
Publication of WO2006024998A3 publication Critical patent/WO2006024998A3/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/74—Projection arrangements for image reproduction, e.g. using eidophor
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/12—Fluid-filled or evacuated lenses
    • G02B3/14—Fluid-filled or evacuated lenses of variable focal length
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
    • G02B26/004—Optical devices or arrangements for the control of light using movable or deformable optical elements based on a displacement or a deformation of a fluid
    • G02B26/005—Optical devices or arrangements for the control of light using movable or deformable optical elements based on a displacement or a deformation of a fluid based on electrowetting
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
    • G02B26/06—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the phase of light
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/48—Laser speckle optics
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/20—Exposure; Apparatus therefor
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/70—Microphotolithographic exposure; Apparatus therefor
    • G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
    • G03F7/7055—Exposure light control in all parts of the microlithographic apparatus, e.g. pulse length control or light interruption
    • G03F7/70583—Speckle reduction, e.g. coherence control or amplitude/wavefront splitting
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3129—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM] scanning a light beam on the display screen

Definitions

  • the present invention relates to a laser projection system, comprising a laser light source for generating a laser beam, means for projecting the laser beam onto a surface, and speckle reduction means for reducing speckle artefacts.
  • the speckle reduction means of this system comprises a moveable diffuser which is driven e.g. by an electric motor.
  • the diffuser reduces the coherence of the laser beam and thus speckle artefacts which otherwise occur when the laser light is incident on a rough surface, such as e.g. paper.
  • control means controls the positions of the first and second fluids based on an electrowetting effect.
  • the speckle reduction means may thus comprise an electrowetting lens.
  • the deflecting properties of the lens need not be used, only the ability to vary the optical path length, which may be well defined.
  • Fig 2 illustrates an electrowetting lens in a first state.
  • Fig 3 illustrates the electrowetting lens in a second state.
  • the present invention relates to laser projection system having means for reducing the coherence, in time, of a laser light beam in order to reduce annoying speckle patterns in an image generated by the system.
  • Speckle is a phenomenon occurring when a highly coherent light beam, such as a laser beam, is scattered by a surface with random surface properties, such as paper, fabric or a painted wall. Different parts of the scattered light add up to a strongly fluctuating light pattern, due to interference resulting in intensity peaks and valleys.
  • the light source 2 may be any kind of laser suitable for illumination, such as for instance a frequency doubled Nd-YAG laser, an Argon-Ion laser or a laser diode.
  • the projection means 4 may e.g. comprise a moveable mirror for projecting the laser beam 3 along a predetermined path on the surface 5, thus producing an image comprising, for instance, text. In that case the mirror is preferably combined with a shutter (not shown) in order to modulate the laser light beam.
  • sweeping projection means producing an image comprising a number of lines similarly to a normal television apparatus
  • projection means comprising liquid crystal modulators.

Abstract

The present invention relates to a laser projection system (1) having means for reducing the coherence of a generated laser beam (3) in order to reduce the occurrence of annoying speckle artefacts in images produced by the system. Coherence is reduced by letting the laser beam (3) pass through a transparent cell (6) comprising first (A) and second (B) immiscible fluids having different refractive indices. The fluids are displaced in the cell, preferably using an electrowetting technique. The cell (6) may thus be realised as an electrowetting lens, which is driven with a pseudo random driving signal.

Description

A laser projection system
FIELD OF THE INVENTION
The present invention relates to a laser projection system, comprising a laser light source for generating a laser beam, means for projecting the laser beam onto a surface, and speckle reduction means for reducing speckle artefacts.
BACKGROUND OF THE INVENTION
Such a system is described in US, Bl, 6594090. The speckle reduction means of this system comprises a moveable diffuser which is driven e.g. by an electric motor. The diffuser reduces the coherence of the laser beam and thus speckle artefacts which otherwise occur when the laser light is incident on a rough surface, such as e.g. paper.
The described system, however, is quite complex and expensive due to the additional moveable mechanical parts needed in the speckle reduction means.
SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a less complex laser projection system which is still capable of substantially reducing annoying speckle artefacts. ..
This object is achieved by means of a laser projection system according to claim 1.
More specifically, the invention relates to a laser projection system, comprising a laser light source for generating a laser beam, means for projecting the laser beam onto a surface, and speckle reduction means for reducing speckle artefacts, wherein said speckle reduction means comprises a transparent cell, arranged in the path of the laser beam, said cell comprising first and second immiscible fluids, having different refractive indices, and control means for controlling the positions of the first and second fluids in the cell in order to vary the optical path length of the laser beam when propagating through the cell.
This arrangement allows the coherence of the laser beam in time to be altered without the provision of mechanical moveable parts, which provides a less complex and expensive system capable of sufficient speckle reduction. Such a system will also be less bulky than a system with a moving diffuser, and will consume less power. A small, low power system may thus be achieved.
Preferably, the control means controls the positions of the first and second fluids based on an electrowetting effect. The speckle reduction means may thus comprise an electrowetting lens. The deflecting properties of the lens need not be used, only the ability to vary the optical path length, which may be well defined.
The electrowetting lens is preferably provided with a pseudo random control signal. This eliminates the risk that the speckle reduction itself becomes visible in an image. Preferably the path length varies more than λ/4, where λ is the wavelength of the light produced by the light source. This provides a suitable variation for reducing the visual annoyance of speckle.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig 1 illustrates schematically a laser projection system according to an embodiment of the invention.
Fig 2 illustrates an electrowetting lens in a first state. Fig 3 illustrates the electrowetting lens in a second state.
DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention relates to laser projection system having means for reducing the coherence, in time, of a laser light beam in order to reduce annoying speckle patterns in an image generated by the system. Speckle is a phenomenon occurring when a highly coherent light beam, such as a laser beam, is scattered by a surface with random surface properties, such as paper, fabric or a painted wall. Different parts of the scattered light add up to a strongly fluctuating light pattern, due to interference resulting in intensity peaks and valleys.
Fig 1 illustrates schematically a laser projection system 1 according to an embodiment of the invention.
The system comprises a laser light source 2 for generating a laser beam 3 and projection means 4 for projecting the laser beam onto a surface 5.
The light source 2 may be any kind of laser suitable for illumination, such as for instance a frequency doubled Nd-YAG laser, an Argon-Ion laser or a laser diode. The projection means 4 may e.g. comprise a moveable mirror for projecting the laser beam 3 along a predetermined path on the surface 5, thus producing an image comprising, for instance, text. In that case the mirror is preferably combined with a shutter (not shown) in order to modulate the laser light beam. Of course, many other types of projection means may be used, such as sweeping projection means producing an image comprising a number of lines similarly to a normal television apparatus, and projection means comprising liquid crystal modulators. In general, any kind of projection means is conceivable according to the invention as long as a highly coherent light source is used and there is a need for the reducing of speckle artefacts. As illustrated in fig 1, the surface 5 on which an image is projected is not considered to be comprised in the projection system 1. The surface 5 may be e.g. an interior or exterior wall of a building, a paper or fabric sheet or the like.
The laser projection system further comprises speckle reduction means 6, 7 for reducing the coherence of the laser beam 3, in order to reduce speckle artefacts. The speckle reduction means 6, 7 comprises a transparent cell 6 and means 7 for controlling and varying the optical path length of the laser beam 3 when propagating through the cell 6.
When the optical path length varies, the coherence of the light beam is reduced, not in space, but in time. This means that the phase of the light varies substantially over time, but that the light beam is instantaneously coherent at any point along its path. This provides an effect that corresponds to vibrating the projection surface 5 in the direction of its normal.
The optical path length is varied by displacing first and second fluids with different refractive indices in the cell 6. By doing this, the distance the laser beam 3 travels through the fluid with the highest refractive index can be made to vary. Preferably, the displacing is carried out using the known electrowetting effect. An example of a cell 6 provided in this way will now be described.
Fig 2 illustrates an electrowetting lens in a first state. The lens constitutes a cell 6 forming part of a speckle reduction means. Electrowetting lenses are known per se, see WO, Al, 03/069380. The lens comprises a tubular side wall part 10 and first and second transparent end walls 11, 12, together defining a cylindrical, closed space. The interior of the side wall part 10 is covered with an electrode layer 14, e.g. a metal layer. The electrode layer is covered by a hydrophobic, insulating layer 15, such as Teflon™ AF 1600 (DuPont™). Said closed space is filled with first A and second B fluids, which are immiscible with each other and have different refractive indices ΏA and nB, respectively. The first fluid A is electrically insulating, e.g. a silicone oil or an alkane. The second fluid B is conductive and polar, e.g. a salt water solution. Preferably, the first and second fluids have equal densities.
In the state illustrated in fig 2, a low or zero voltage Vi is applied between the second fluid B and the electrode 14. The cell is thus relaxed. In this state, the second fluid B, being polar, will cover as little of the hydrophobic layer 15 as possible, which means that the interface 17 between the first A and second B fluids will bulge towards the left end wall 11. A laser beam, travelling along the central path 19 will thus travel the distance LAi through the first fluid A and the distance LBI through the second fluid B. The total optical path length will thus be LAi*nA+LBi*nB. Note that the deflecting properties of the lens are not used in this application.
Fig 3 illustrates the electrowetting lens in a second state. In this state a second, higher voltage V2 is applied between the second fluid B and the electrode 14. Only a very small leakage current will flow in this circuit, since the hydrophobic layer 15 is insulating, but the applied voltage now forces the second, conductive fluid B to cover a greater part of the hydrophobic layer 15. The interface 17 between the first and second fluids thus flexes and begins to bulge instead towards the right end wall 12. Therefore, a laser beam, travelling along the central path 19 will now travel the distance LA2 through the first fluid A and the distance LB2 through the second fluid B. The total optical path length will now be LA2*nA+LB2*nB.
In accordance with an embodiment of the invention, the lens, constituting a cell 6, is controlled by a control unit 7 to alternate between the state of fig 2 and the state of fig 3. The optical path length difference Δd will thus be (LAi*nA+LBi*nB)-(LA2*nA+LB2*nβ). Of course, more than two states may be used or the optical path length may be caused to vary continuously. Preferably, Δd should be greater than λ/4 where λ is the wavelength of the laser light. To be visible to the human eye, a speckle pattern must be constant over about 0.1 second. To reduce annoying speckle patterns, the path length should be varied with a frequency higher than 10 Hz, preferably higher than 50 Hz. Preferably a pseudo random driving signal is used to control the optical path length. This avoids a risk that the coherence reduction itself becomes visible to a user. One or more of the amplitude, the frequency and the phase of the driving signal may have random properties. In summary, the present invention relates to a laser projection system having means for reducing the coherence of a generated laser beam in order to reduce the occurrence of annoying speckle artefacts in images produced by the system. Coherence is reduced by letting the laser beam pass through a transparent cell comprising first and second immiscible fluids having different refractive indices. The fluids are displaced in the cell, preferably using an electrowetting technique. The cell may thus be realised as an electrowetting lens, which is driven with a pseudo random driving signal.
The invention is not restricted to the described embodiment. It can be altered in different ways within the scope of the appended claims.

Claims

CLAIMS:
1. A laser projection system, comprising a laser light source (2) for generating a laser beam (3), means (4) for projecting the laser beam (3) onto a surface, and speckle reduction means for reducing speckle artefacts, wherein said speckle reduction means (6, 7) comprises a transparent cell (6), arranged in the path of the laser beam (3), said cell (6) comprising first (A) and second (B) immiscible fluids, having different refractive indices, and control means (7) for controlling the positions of the first (A) and second (B) fluids in the cell (6) in order to vary the optical path length of the laser beam (3) when propagating through the cell (6).
2. A laser projection system according to claim 1, wherein the control means (7) controls the positions of the first (A) and second (B) fluids based on an electro wetting effect.
3. A laser projection system according to claim 2, wherein the speckle reduction means comprises an electrowetting lens.
4. A laser projection system according to claim 3, wherein the electrowetting lens is provided with a pseudo random control signal.
5. A laser projection system according any of the preceding claims, wherein said optical path length varies more than λ/4 where λ is the wavelength of the light produced by the light source (2).
PCT/IB2005/052787 2004-08-30 2005-08-25 A laser projection system WO2006024998A2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP05781102A EP1787167B1 (en) 2004-08-30 2005-08-25 Laser projection system
US11/573,915 US7775670B2 (en) 2004-08-30 2005-08-25 Laser projection system
DE602005005836T DE602005005836T2 (en) 2004-08-30 2005-08-25 Laser projection system
JP2007529095A JP4658127B2 (en) 2004-08-30 2005-08-25 Laser projection system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP04104148.4 2004-08-30
EP04104148 2004-08-30

Publications (2)

Publication Number Publication Date
WO2006024998A2 true WO2006024998A2 (en) 2006-03-09
WO2006024998A3 WO2006024998A3 (en) 2006-10-26

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PCT/IB2005/052787 WO2006024998A2 (en) 2004-08-30 2005-08-25 A laser projection system

Country Status (8)

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US (1) US7775670B2 (en)
EP (1) EP1787167B1 (en)
JP (1) JP4658127B2 (en)
KR (1) KR20070048205A (en)
CN (1) CN100483259C (en)
AT (1) ATE391309T1 (en)
DE (1) DE602005005836T2 (en)
WO (1) WO2006024998A2 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009051720A1 (en) * 2007-10-16 2009-04-23 Lucent Technologies Inc. Speckle reduction using a tunable liquid lens
JPWO2008088001A1 (en) * 2007-01-18 2010-05-13 シャープ株式会社 Optical element and image display apparatus using the same
WO2010125562A1 (en) 2009-04-26 2010-11-04 X.D.M. Ltd. Laser projector with reduced speckle effect
US8077367B2 (en) 2009-04-29 2011-12-13 Corning Incorporated Speckle mitigation in laser projection systems
US8130433B2 (en) 2009-04-29 2012-03-06 Corning Incorporated Spinning optics for speckle mitigation in laser projection systems
CN105093559A (en) * 2014-05-15 2015-11-25 中国科学院理化技术研究所 Decoherence apparatus

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2472312A4 (en) * 2009-09-16 2013-01-30 Sharp Kk Display element and electric apparatus using same
DE102011101323A1 (en) * 2011-05-12 2012-11-15 Osram Opto Semiconductors Gmbh Optoelectronic component for use in e.g. projection application, has control device operating optical phase switch, where different optical path lengths are assigned for laser light for different modes of operation of optical phase switch
DE102014118378A1 (en) * 2014-12-11 2016-06-16 Hella Kgaa Hueck & Co. Lighting device for vehicles
JP2018031990A (en) * 2016-08-26 2018-03-01 大日本印刷株式会社 Screen and display

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5272473A (en) * 1989-02-27 1993-12-21 Texas Instruments Incorporated Reduced-speckle display system
US20010007510A1 (en) * 1996-06-11 2001-07-12 Andreas Dorsel Method and apparatus for reducing the formation of spots in laser projection
US20020126981A1 (en) * 2001-02-20 2002-09-12 Eastman Kodak Company Speckle suppressed laser projection system with partial beam reflection
WO2005006720A1 (en) * 2003-07-14 2005-01-20 Koninklijke Philips Electronics N.V. Projection device

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2755349B2 (en) 1987-09-17 1998-05-20 オリンパス光学工業株式会社 Illumination optical system of semiconductor exposure equipment
JPH05173094A (en) 1991-12-20 1993-07-13 Sony Corp Laser display device
US6629641B2 (en) * 2000-06-07 2003-10-07 Metrologic Instruments, Inc. Method of and system for producing images of objects using planar laser illumination beams and image detection arrays
JP3986137B2 (en) 1997-09-26 2007-10-03 オリンパス株式会社 Laser illumination device and optical device using the same
FR2769375B1 (en) * 1997-10-08 2001-01-19 Univ Joseph Fourier VARIABLE FOCAL LENS
US6816302B2 (en) * 1998-03-02 2004-11-09 Micronic Laser Systems Ab Pattern generator
US6069739A (en) * 1998-06-30 2000-05-30 Intel Corporation Method and lens arrangement to improve imaging performance of microlithography exposure tool
JP4345127B2 (en) 1999-03-18 2009-10-14 ソニー株式会社 Lighting device and lighting method
US6839469B2 (en) * 2000-01-21 2005-01-04 Lam K. Nguyen Multiparallel three dimensional optical microscopy system
JP2002267825A (en) 2001-03-09 2002-09-18 Sony Corp Diffraction type lens element and illumination device using the same
US6594090B2 (en) * 2001-08-27 2003-07-15 Eastman Kodak Company Laser projection display system
US6577429B1 (en) * 2002-01-15 2003-06-10 Eastman Kodak Company Laser projection display system
KR101016253B1 (en) 2002-02-14 2011-02-25 코닌클리케 필립스 일렉트로닉스 엔.브이. Variable focus lens
JP4290095B2 (en) * 2004-08-16 2009-07-01 キヤノン株式会社 Display optical system and image display system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5272473A (en) * 1989-02-27 1993-12-21 Texas Instruments Incorporated Reduced-speckle display system
US20010007510A1 (en) * 1996-06-11 2001-07-12 Andreas Dorsel Method and apparatus for reducing the formation of spots in laser projection
US20020126981A1 (en) * 2001-02-20 2002-09-12 Eastman Kodak Company Speckle suppressed laser projection system with partial beam reflection
WO2005006720A1 (en) * 2003-07-14 2005-01-20 Koninklijke Philips Electronics N.V. Projection device

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2008088001A1 (en) * 2007-01-18 2010-05-13 シャープ株式会社 Optical element and image display apparatus using the same
WO2009051720A1 (en) * 2007-10-16 2009-04-23 Lucent Technologies Inc. Speckle reduction using a tunable liquid lens
US7862183B2 (en) 2007-10-16 2011-01-04 Alcatel-Lucent Usa Inc. Speckle reduction using a tunable liquid lens
JP2011502274A (en) * 2007-10-16 2011-01-20 アルカテル−ルーセント ユーエスエー インコーポレーテッド Speckle reduction using adjustable liquid lens
WO2010125562A1 (en) 2009-04-26 2010-11-04 X.D.M. Ltd. Laser projector with reduced speckle effect
US8077367B2 (en) 2009-04-29 2011-12-13 Corning Incorporated Speckle mitigation in laser projection systems
US8130433B2 (en) 2009-04-29 2012-03-06 Corning Incorporated Spinning optics for speckle mitigation in laser projection systems
CN105093559A (en) * 2014-05-15 2015-11-25 中国科学院理化技术研究所 Decoherence apparatus

Also Published As

Publication number Publication date
US7775670B2 (en) 2010-08-17
DE602005005836T2 (en) 2009-05-14
KR20070048205A (en) 2007-05-08
JP2008511853A (en) 2008-04-17
CN100483259C (en) 2009-04-29
US20080278692A1 (en) 2008-11-13
DE602005005836D1 (en) 2008-05-15
ATE391309T1 (en) 2008-04-15
WO2006024998A3 (en) 2006-10-26
EP1787167A2 (en) 2007-05-23
CN101010638A (en) 2007-08-01
EP1787167B1 (en) 2008-04-02
JP4658127B2 (en) 2011-03-23

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