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GB9214617D0 - Improvements in or relating to interferometers - Google Patents

Improvements in or relating to interferometers

Info

Publication number
GB9214617D0
GB9214617D0 GB9214617A GB9214617A GB9214617D0 GB 9214617 D0 GB9214617 D0 GB 9214617D0 GB 9214617 A GB9214617 A GB 9214617A GB 9214617 A GB9214617 A GB 9214617A GB 9214617 D0 GB9214617 D0 GB 9214617D0
Authority
GB
United Kingdom
Prior art keywords
noise
measurement
signal
interferometers
relating
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.)
Granted
Application number
GB9214617A
Other versions
GB2268582A (en
GB2268582B (en
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.)
Roke Manor Research Ltd
Original Assignee
Roke Manor Research Ltd
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 Roke Manor Research Ltd filed Critical Roke Manor Research Ltd
Priority to GB9214617A priority Critical patent/GB2268582B/en
Publication of GB9214617D0 publication Critical patent/GB9214617D0/en
Publication of GB2268582A publication Critical patent/GB2268582A/en
Application granted granted Critical
Publication of GB2268582B publication Critical patent/GB2268582B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B9/00—Measuring instruments characterised by the use of optical techniques
    • G01B9/02—Interferometers
    • G01B9/02055—Reduction or prevention of errors; Testing; Calibration
    • G01B9/0207—Error reduction by correction of the measurement signal based on independently determined error sources, e.g. using a reference interferometer
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B2290/00—Aspects of interferometers not specifically covered by any group under G01B9/02
    • G01B2290/60—Reference interferometer, i.e. additional interferometer not interacting with object

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Instruments For Measurement Of Length By Optical Means (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

An optical interferometer wherein laser noise is reduced or removed by providing an additional optical path (15) in which the noise present can be ascertained and then subtracted from the measurement signal, also containing noise, such that the output signal has an improved signal to noise ratio. The noise may be identified using a-reference interferometer and both the measurement and noise signals may be appropriately processed (11, 24) and filtered (26, 28) before the subtraction stage (30). The system may also be adaptable to other forms of electromagnetic radiation. <IMAGE>
GB9214617A 1992-07-09 1992-07-09 Improvements in or relating to interferometers Expired - Fee Related GB2268582B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB9214617A GB2268582B (en) 1992-07-09 1992-07-09 Improvements in or relating to interferometers

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB9214617A GB2268582B (en) 1992-07-09 1992-07-09 Improvements in or relating to interferometers

Publications (3)

Publication Number Publication Date
GB9214617D0 true GB9214617D0 (en) 1992-08-26
GB2268582A GB2268582A (en) 1994-01-12
GB2268582B GB2268582B (en) 1995-12-20

Family

ID=10718465

Family Applications (1)

Application Number Title Priority Date Filing Date
GB9214617A Expired - Fee Related GB2268582B (en) 1992-07-09 1992-07-09 Improvements in or relating to interferometers

Country Status (1)

Country Link
GB (1) GB2268582B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112424562A (en) * 2018-05-18 2021-02-26 密歇根大学董事会 Path fluctuation monitoring for frequency modulation interferometer

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4436922C2 (en) * 1994-10-15 1997-07-31 Jenoptik Technologie Gmbh Interferometer arrangement for frequency and environmental independent length measurement

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3706347A1 (en) * 1987-02-27 1988-09-08 Fraunhofer Ges Forschung LASER INTERFEROMETER FOR INTERFEROMETRIC LENGTH MEASUREMENT
FR2650664B1 (en) * 1989-08-01 1991-11-15 Micro Controle INTERFEROMETRY DISPLACEMENT MEASUREMENT DEVICE
GB9018215D0 (en) * 1990-08-20 1990-10-03 Nat Res Dev Optical apparatus

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112424562A (en) * 2018-05-18 2021-02-26 密歇根大学董事会 Path fluctuation monitoring for frequency modulation interferometer
CN112424562B (en) * 2018-05-18 2023-07-07 密歇根大学董事会 Path fluctuation monitoring for frequency modulated interferometers

Also Published As

Publication number Publication date
GB2268582A (en) 1994-01-12
GB2268582B (en) 1995-12-20

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Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 20110709