WO2002044647A3 - Improved linear variable differential transformers for high precision position measurements - Google Patents

Improved linear variable differential transformers for high precision position measurements Download PDF

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Publication number
WO2002044647A3
WO2002044647A3 PCT/US2001/048283 US0148283W WO0244647A3 WO 2002044647 A3 WO2002044647 A3 WO 2002044647A3 US 0148283 W US0148283 W US 0148283W WO 0244647 A3 WO0244647 A3 WO 0244647A3
Authority
WO
WIPO (PCT)
Prior art keywords
linear variable
improved
variable differential
primary coil
high permeability
Prior art date
Application number
PCT/US2001/048283
Other languages
French (fr)
Other versions
WO2002044647A2 (en
Inventor
Roger Proksch
Jason Cleveland
Dan Bocek
Original Assignee
Asylum Research Corp
Roger Proksch
Jason Cleveland
Dan Bocek
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 Asylum Research Corp, Roger Proksch, Jason Cleveland, Dan Bocek filed Critical Asylum Research Corp
Priority to AU2002229050A priority Critical patent/AU2002229050A1/en
Priority to JP2002546150A priority patent/JP2004523737A/en
Priority to EP01990186A priority patent/EP1340040A4/en
Priority to KR1020037007329A priority patent/KR100794976B1/en
Publication of WO2002044647A2 publication Critical patent/WO2002044647A2/en
Publication of WO2002044647A3 publication Critical patent/WO2002044647A3/en

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/14—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring distance or clearance between spaced objects or spaced apertures
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01Q—SCANNING-PROBE TECHNIQUES OR APPARATUS; APPLICATIONS OF SCANNING-PROBE TECHNIQUES, e.g. SCANNING PROBE MICROSCOPY [SPM]
    • G01Q10/00—Scanning or positioning arrangements, i.e. arrangements for actively controlling the movement or position of the probe
    • G01Q10/04—Fine scanning or positioning
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y35/00—Methods or apparatus for measurement or analysis of nanostructures
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
    • G01D5/20—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature
    • G01D5/204—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature by influencing the mutual induction between two or more coils
    • G01D5/2066—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature by influencing the mutual induction between two or more coils by movement of a single coil with respect to a single other coil
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
    • G01D5/20—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature
    • G01D5/22—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature differentially influencing two coils
    • G01D5/2291—Linear or rotary variable differential transformers (LVDTs/RVDTs) having a single primary coil and two secondary coils
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F21/00—Variable inductances or transformers of the signal type
    • H01F21/02—Variable inductances or transformers of the signal type continuously variable, e.g. variometers
    • H01F21/04—Variable inductances or transformers of the signal type continuously variable, e.g. variometers by relative movement of turns or parts of windings

Abstract

A transducer that reduces noise, increases sensitivity, and improved the time response of a linear variable differential transformer (LVDT). The device replaces the primary coil and the high permeability ferromagnetic core of conventional LVDTs with a primary coil (15) wound around a moving non-ferromagnetic core (14). In addition to reducing or eliminating Barkhausen noise, this approach reduced or eliminated a number of other undesirable effects in conventional LVDTs including excessive eddy current heating in the core, non-linearities associated with high permeability materials and the length scale of the flux circuit. These improvements are coupled with improved LVDT signal conditioning circuitry. The device is also an actuator and may be used to convert differential voltages into force. Devices with these improvements have numerous applications, including molecular force measurements, atomic force microscopy and manipulation technology, lithographic manufacturing, nanometer scale surface profiling and other aspects of nanotechnology.
PCT/US2001/048283 2000-11-30 2001-11-30 Improved linear variable differential transformers for high precision position measurements WO2002044647A2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
AU2002229050A AU2002229050A1 (en) 2000-11-30 2001-11-30 Improved linear variable differential transformers for high precision position measurements
JP2002546150A JP2004523737A (en) 2000-11-30 2001-11-30 Improved linear variable differential transformer for accurate position measurement
EP01990186A EP1340040A4 (en) 2000-11-30 2001-11-30 Improved linear variable differential transformers for high precision position measurements
KR1020037007329A KR100794976B1 (en) 2000-11-30 2001-11-30 Improved linear variable differential transformers for high precision position measurements

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US25031300P 2000-11-30 2000-11-30
US60/250,313 2000-11-30
US33224301P 2001-11-16 2001-11-16
US60/332,243 2001-11-16

Publications (2)

Publication Number Publication Date
WO2002044647A2 WO2002044647A2 (en) 2002-06-06
WO2002044647A3 true WO2002044647A3 (en) 2003-01-16

Family

ID=26940790

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2001/048283 WO2002044647A2 (en) 2000-11-30 2001-11-30 Improved linear variable differential transformers for high precision position measurements

Country Status (7)

Country Link
US (8) US20020175677A1 (en)
EP (1) EP1340040A4 (en)
JP (2) JP2004523737A (en)
KR (1) KR100794976B1 (en)
CN (1) CN1483136A (en)
AU (1) AU2002229050A1 (en)
WO (1) WO2002044647A2 (en)

Families Citing this family (68)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020175677A1 (en) * 2000-11-30 2002-11-28 Roger Proksch Linear variable differential transformers for high precision position measurements
JP3888427B2 (en) * 2001-10-30 2007-03-07 学校法人日本大学 Displacement sensor
JP2005527817A (en) 2002-05-24 2005-09-15 アサイラム リサーチ コーポレーション Linear variable differential transformer with digital electronics
WO2004057303A2 (en) * 2002-12-18 2004-07-08 Asylum Research Corporation Fully digital controller for cantilever-based instruments
US7165445B2 (en) * 2003-08-25 2007-01-23 Asylum Research Corporation Digital control of quality factor in resonant systems including cantilever based instruments
US8711089B2 (en) 2004-11-29 2014-04-29 Fujitsu Component Limited Position detection device, pointing device and input device
WO2006121146A1 (en) * 2005-05-12 2006-11-16 Matsushita Electric Works, Ltd. Position sensor
FR2888319B1 (en) * 2005-07-07 2008-02-15 Nanotec Solution Soc Civ Ile METHOD FOR NON-CONTACT MEASUREMENT OF RELATIVE DISPLACEMENT OR RELATIVE POSITIONING OF A FIRST OBJECT IN RELATION TO A SECOND OBJECT INDUCINGLY.
US7786836B2 (en) * 2005-07-19 2010-08-31 Lctank Llc Fabrication of inductors in transformer based tank circuitry
US7508280B2 (en) * 2005-07-19 2009-03-24 Lc Tank Llc Frequency adjustment techniques in coupled LC tank circuits
US7250826B2 (en) * 2005-07-19 2007-07-31 Lctank Llc Mutual inductance in transformer based tank circuitry
US7511588B2 (en) * 2005-07-19 2009-03-31 Lctank Llc Flux linked LC tank circuits forming distributed clock networks
US7941286B2 (en) 2006-01-31 2011-05-10 Asylum Research Corporation Variable density scanning
US8302456B2 (en) 2006-02-23 2012-11-06 Asylum Research Corporation Active damping of high speed scanning probe microscope components
US7631546B2 (en) * 2006-06-30 2009-12-15 Veeco Instruments Inc. Method and apparatus for monitoring of a SPM actuator
US8348628B2 (en) * 2006-08-15 2013-01-08 General Electric Company System and method for monitoring a reciprocating compressor
KR100828737B1 (en) * 2006-11-14 2008-05-13 두원공과대학산학협력단 Linear variable differential transformer
GB0707376D0 (en) * 2007-04-17 2007-05-23 Penny & Giles Controls Ltd Inductive sensors
US8156568B2 (en) * 2007-04-27 2012-04-10 Picocal, Inc. Hybrid contact mode scanning cantilever system
US7605585B2 (en) 2007-05-08 2009-10-20 Honeywell International Inc. Air-core transformer position sensor
WO2009037967A1 (en) * 2007-09-20 2009-03-26 Panasonic Electric Works Co., Ltd. Sensing unit for proximity sensor and proximity sensor
ES2307450A1 (en) * 2008-04-16 2008-11-16 Universidad Politecnica De Madrid Magnetic device position sensor (Machine-translation by Google Translate, not legally binding)
JP5052413B2 (en) * 2008-05-27 2012-10-17 株式会社荏原製作所 Substrate observation apparatus and substrate polishing apparatus
EP2163906B1 (en) * 2008-09-16 2014-02-26 Mitutoyo Corporation Method of detecting a movement of a measuring probe and measuring instrument
EP2342532A4 (en) * 2008-10-14 2013-10-30 Roger Proksch Modular atomic force microscope
US8502525B2 (en) 2008-10-14 2013-08-06 Oxford Instruments Plc Integrated micro actuator and IVDT for high precision position measurements
US8977343B2 (en) * 2008-10-28 2015-03-10 Koninklijke Philips N.V. Optical probe having a position measuring system
EP2199733B1 (en) * 2008-12-17 2013-02-13 Mitutoyo Corporation Electric circuit and method of operating a measuring instrument
EP2211187B1 (en) 2009-01-14 2013-10-02 Mitutoyo Corporation Method of actuating a system, apparatus for modifying a control signal for actuation of a system and method of tuning such an apparatus
DE102009022404A1 (en) * 2009-05-25 2010-12-02 Liebherr-Aerospace Lindenberg Gmbh spindle drive
CN101852102B (en) * 2010-06-18 2015-10-28 天津市电力公司 The speed regulation valve of steam turbine mechanism of a kind of exportable accurate shut-in time
US8264315B2 (en) 2010-08-03 2012-09-11 Honeywell International Inc. Linear variable differential transformers
US8879067B2 (en) * 2010-09-01 2014-11-04 Lake Shore Cryotronics, Inc. Wavelength dependent optical force sensing
US8558408B2 (en) 2010-09-29 2013-10-15 General Electric Company System and method for providing redundant power to a device
US8478560B2 (en) 2011-01-19 2013-07-02 Honeywell International Inc. Three wire transformer position sensor, signal processing circuitry, and temperature compensation circuitry therefor
US8278779B2 (en) 2011-02-07 2012-10-02 General Electric Company System and method for providing redundant power to a device
JP4852667B1 (en) * 2011-03-04 2012-01-11 株式会社マコメ研究所 Proximity sensor
US8712710B2 (en) 2011-05-13 2014-04-29 Honeywell International Inc. Method and apparatus for detection of LVDT core fallout condition
JP2013007666A (en) * 2011-06-24 2013-01-10 Ulvac Japan Ltd Stylus type step profiler for surface shape measurement and measurement accuracy improvement method in the same
US9068815B1 (en) * 2011-11-09 2015-06-30 Sturman Industries, Inc. Position sensors and methods
US9021677B1 (en) * 2012-01-12 2015-05-05 Gemcor Ii, Llc Apparatus and method for improving safety and quality of automatic riveting operations
US20140253279A1 (en) * 2013-03-08 2014-09-11 Qualcomm Incorporated Coupled discrete inductor with flux concentration using high permeable material
JP2014188122A (en) * 2013-03-27 2014-10-06 Akita Prefectural Hospital Organization Magnetic substance detection sensor, magnetic substance detection method, and magnetic substance detection apparatus
US20150008906A1 (en) * 2013-07-03 2015-01-08 Dennis K. Briefer Position sensing device
US9463948B2 (en) * 2013-09-19 2016-10-11 General Electric Company Control methods for producing precision coils
KR101563320B1 (en) * 2013-10-10 2015-10-26 현대중공업 주식회사 High speed solenoid
KR101502703B1 (en) * 2013-11-19 2015-03-24 한국원자력연구원 Apparatus for measuring for deflection of a movable member of control element drive mechanism
US9097737B2 (en) 2013-11-25 2015-08-04 Oxford Instruments Asylum Research, Inc. Modular atomic force microscope with environmental controls
US9863787B2 (en) 2014-07-31 2018-01-09 Parker-Hannifin Corporation Linear variable differential transformer with multi-range secondary windings for high precision
DE102014013975B4 (en) * 2014-09-19 2020-09-24 Knorr-Bremse Systeme für Nutzfahrzeuge GmbH Electrical signal input device with converging or diverging resonant circuit signals
CN104748661B (en) * 2015-04-17 2018-02-23 兰州理工大学 Differential transformer displacement transducer
US10775198B2 (en) * 2015-11-04 2020-09-15 Amiteq Co., Ltd. Displacement detection device
CN106052538B (en) * 2016-06-23 2018-08-03 国家电网公司 A kind of water turbine set shafting dynamical system state on-line diagnosing apparatus and method
DE102016215212A1 (en) * 2016-08-16 2018-02-22 Robert Bosch Gmbh Movement device with magnetic position determination and data transmission device
GB2563948A (en) * 2017-06-30 2019-01-02 Airbus Operations Ltd Aircraft landing gear assembly
US10996078B2 (en) 2017-11-10 2021-05-04 Honeywell International Inc. C-shaped cylindrical core for linear variable differential transformer (LVDT) probes
CN109870098A (en) * 2017-12-04 2019-06-11 北京自动化控制设备研究所 A kind of unmanned plane rudder system method for detecting position
WO2020033041A1 (en) * 2018-08-07 2020-02-13 Halliburton Energy Services, Inc. Caliper tool and sensor for use in high pressure environments
KR102137987B1 (en) 2018-08-27 2020-07-27 울산과학기술원 Method of manufacturing an electrode material having perovskite crystal structure material using infiltration method, and metal air battery, solid oxide fuel cell, and solid oxide electrolyzer cell having the electrode material manufactured by the same
US11644298B2 (en) 2018-11-01 2023-05-09 Mitutoyo Corporation Inductive position detection configuration for indicating a measurement device stylus position
US11740064B2 (en) 2018-11-01 2023-08-29 Mitutoyo Corporation Inductive position detection configuration for indicating a measurement device stylus position
JP7261144B2 (en) * 2018-11-01 2023-04-19 株式会社ミツトヨ Inductive position detection arrangement for indicating stylus position of a measuring device
US10955263B2 (en) * 2019-04-18 2021-03-23 Honeywell International Inc. Apparatuses, systems, and methods for improved sensor devices
CN111312491B (en) * 2020-03-09 2021-08-20 南方科技大学 Coupling plane coil, displacement sensor and wearable electronic product
CN111539179B (en) * 2020-04-28 2022-10-18 厦门乃尔电子有限公司 Calculation and design winding method of high-sensitivity LVDT
CN112285796B (en) * 2020-10-10 2022-04-15 国网湖南省电力有限公司 Oil-immersed reactor noise prediction method based on reciprocity principle
US20220205816A1 (en) * 2020-12-24 2022-06-30 Renesas Electronics America Inc. Display screen position sensing using inductive sensing
EP4206687A1 (en) 2021-02-03 2023-07-05 Oxford Instruments Asylum Research, Inc. Automated optimization of afm light source positioning

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2452862A (en) * 1945-10-19 1948-11-02 Jack & Heintz Prec Ind Inc Electric gauging head
US2503851A (en) * 1944-06-20 1950-04-11 Fed Products Corp Electrical gauge

Family Cites Families (47)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US513518A (en) * 1894-01-30 Commutator
US2364237A (en) * 1943-11-08 1944-12-05 Jack & Heintz Inc Electrical caliper
US2564221A (en) * 1948-01-22 1951-08-14 Bailey Meter Co Electromagnetic motion responsive device
US3005969A (en) * 1957-07-06 1961-10-24 Constr Meccaniche Riva S P A Position transducer adapted to transduce the displacement of a mechanical member into an alternate voltage
US3100292A (en) * 1960-01-08 1963-08-06 Textron Electronics Inc Vibration pickup
US3891918A (en) * 1971-03-23 1975-06-24 James F Ellis Linear displacement transducer utilizing an oscillator whose average period varies as a linear function of the displacement
US3662306A (en) * 1971-03-24 1972-05-09 Gen Instrument Corp Adjustably coupled radio frequency transformer
GB1436539A (en) 1972-11-30 1976-05-19 Eastern Electronics Norwich Transformers
DE2410047A1 (en) * 1974-03-02 1975-09-11 Nix Steingroeve Elektro Physik ELECTROMAGNETIC THICKNESS GAUGE WITH SWITCHABLE MEASURING FREQUENCY
US4030085A (en) * 1976-07-20 1977-06-14 The United States Of America As Represented By The United States Energy Research And Development Administration Nonferromagnetic linear variable differential transformer
ZA794794B (en) * 1978-09-28 1980-08-27 Lucas Industries Ltd Displacement transducers
JPS5713303A (en) * 1980-06-30 1982-01-23 Hitachi Ltd Device for detecting position
US5046427A (en) 1982-11-01 1991-09-10 The United States Of America As Represented By The Secretary Of The Navy Differential pressure sensor
JPS60155570U (en) * 1984-03-26 1985-10-16 株式会社瑞穂製作所 Movement amount detection device
US4669300A (en) * 1984-03-30 1987-06-02 Sloan Technology Corporation Electromagnetic stylus force adjustment mechanism
JPS61187603A (en) * 1985-02-15 1986-08-21 Yaskawa Electric Mfg Co Ltd Linear resolver
US4667158A (en) * 1985-04-01 1987-05-19 Redlich Robert W Linear position transducer and signal processor
US5046702A (en) * 1987-03-14 1991-09-10 Kabushiki Kaisha Kambayashi Seisakujo Solenoid device
US4935634A (en) 1989-03-13 1990-06-19 The Regents Of The University Of California Atomic force microscope with optional replaceable fluid cell
JPH0378617A (en) 1989-08-22 1991-04-03 K G S Kk Position sensor
JPH03173530A (en) * 1989-12-04 1991-07-26 Hitachi Ltd Inclined magnetic field coil of magnetic resonance imaging device
US5432444A (en) * 1990-10-23 1995-07-11 Kaisei Engineer Co., Ltd. Inspection device having coaxial induction and exciting coils forming a unitary coil unit
DE4131595C2 (en) 1991-09-23 1995-02-09 Rheinmetall Gmbh Electromagnetic accelerator in flat coil arrangement
DE59308536D1 (en) * 1992-04-02 1998-06-18 Micro Epsilon Messtechnik METHOD FOR SENSOR CONTROL AND SIGNAL PROCESSING
US5278496A (en) * 1992-05-22 1994-01-11 Component Sales & Consultants, Inc. High output and environmentally impervious variable reluctance sensor
US5469053A (en) * 1992-11-02 1995-11-21 A - Tech Corporation E/U core linear variable differential transformer for precise displacement measurement
US5461319A (en) * 1992-12-28 1995-10-24 Peters; Randall D. Symmetric differential capacitance transducer employing cross coupled conductive plates to form equipotential pairs
US5414939A (en) * 1993-06-28 1995-05-16 Owens-Brockway Glass Container Inc. Contact measurement of container dimensional parameters
US5465046A (en) * 1994-03-21 1995-11-07 Campbell; Ann. N. Magnetic force microscopy method and apparatus to detect and image currents in integrated circuits
JPH07270178A (en) * 1994-03-29 1995-10-20 Japan Steel Works Ltd:The Apparatus for detecting position of core of differential transformer
US5513518A (en) * 1994-05-19 1996-05-07 Molecular Imaging Corporation Magnetic modulation of force sensor for AC detection in an atomic force microscope
JPH08114464A (en) * 1994-10-17 1996-05-07 Yokogawa Electron Kk Signal converter circuit
US5948972A (en) * 1994-12-22 1999-09-07 Kla-Tencor Corporation Dual stage instrument for scanning a specimen
US5705741A (en) * 1994-12-22 1998-01-06 Tencor Instruments Constant-force profilometer with stylus-stabilizing sensor assembly, dual-view optics, and temperature drift compensation
JPH08262037A (en) * 1995-03-27 1996-10-11 Olympus Optical Co Ltd Scanning probe microscope
US5739686A (en) * 1996-04-30 1998-04-14 Naughton; Michael J. Electrically insulating cantilever magnetometer with mutually isolated and integrated thermometry, background elimination and null detection
US5767670A (en) * 1996-08-29 1998-06-16 Texas Instruments Incorporated Method and apparatus for providing improved temperature compensated output for variable differential transformer system
US5777468A (en) * 1996-12-19 1998-07-07 Texas Instruments Incorporated Variable differential transformer system and method providing improved temperature stability and sensor fault detection apparatus
JPH10246607A (en) * 1997-03-04 1998-09-14 Kawasaki Heavy Ind Ltd Displacement detector
JPH10300410A (en) 1997-04-28 1998-11-13 Shinko Electric Co Ltd Position sensor for high temperature
JPH11230973A (en) * 1998-02-16 1999-08-27 Olympus Optical Co Ltd Chip holding mechanism
US6043573A (en) * 1998-11-12 2000-03-28 Systems, Machines, Automation Components, Corporation Linear actuator with burn-out-proof coil
US20020175677A1 (en) 2000-11-30 2002-11-28 Roger Proksch Linear variable differential transformers for high precision position measurements
US20030209060A1 (en) 2002-05-08 2003-11-13 Roger Proksch Apparatus and method for isolating and measuring movement in metrology apparatus
JP2005527817A (en) 2002-05-24 2005-09-15 アサイラム リサーチ コーポレーション Linear variable differential transformer with digital electronics
WO2004057303A2 (en) 2002-12-18 2004-07-08 Asylum Research Corporation Fully digital controller for cantilever-based instruments
US7165445B2 (en) 2003-08-25 2007-01-23 Asylum Research Corporation Digital control of quality factor in resonant systems including cantilever based instruments

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2503851A (en) * 1944-06-20 1950-04-11 Fed Products Corp Electrical gauge
US2452862A (en) * 1945-10-19 1948-11-02 Jack & Heintz Prec Ind Inc Electric gauging head

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP1340040A4 *

Also Published As

Publication number Publication date
EP1340040A4 (en) 2007-02-28
JP2008102144A (en) 2008-05-01
EP1340040A2 (en) 2003-09-03
WO2002044647A2 (en) 2002-06-06
US7038443B2 (en) 2006-05-02
US7372254B2 (en) 2008-05-13
US7262592B2 (en) 2007-08-28
CN1483136A (en) 2004-03-17
AU2002229050A1 (en) 2002-06-11
KR20030084903A (en) 2003-11-01
JP2004523737A (en) 2004-08-05
US20060192551A1 (en) 2006-08-31
US20040075428A1 (en) 2004-04-22
US20020175677A1 (en) 2002-11-28
US20060186878A1 (en) 2006-08-24
US7459904B2 (en) 2008-12-02
US7233140B2 (en) 2007-06-19
US20060186876A1 (en) 2006-08-24
US20060202683A1 (en) 2006-09-14
US20070200559A1 (en) 2007-08-30
US7271582B2 (en) 2007-09-18
US20060186877A1 (en) 2006-08-24
KR100794976B1 (en) 2008-01-16

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