[go: up one dir, main page]

WO1996016326A1 - Instrument optique - Google Patents

Instrument optique Download PDF

Info

Publication number
WO1996016326A1
WO1996016326A1 PCT/GB1995/002727 GB9502727W WO9616326A1 WO 1996016326 A1 WO1996016326 A1 WO 1996016326A1 GB 9502727 W GB9502727 W GB 9502727W WO 9616326 A1 WO9616326 A1 WO 9616326A1
Authority
WO
WIPO (PCT)
Prior art keywords
thread
liquid
instrument according
detector
window
Prior art date
Application number
PCT/GB1995/002727
Other languages
English (en)
Inventor
Mark Johnson
Original Assignee
United Utilities Plc
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 United Utilities Plc filed Critical United Utilities Plc
Priority to GB9710452A priority Critical patent/GB2310282B/en
Priority to AU38781/95A priority patent/AU3878195A/en
Publication of WO1996016326A1 publication Critical patent/WO1996016326A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/255—Details, e.g. use of specially adapted sources, lighting or optical systems

Definitions

  • the present invention relates to an instrument for monitoring characteristics of a liquid, and in particular to such an instrument which is capable of being used to monitor the characteristics of a liquid such as water.
  • optical techniques to monitor the quality of water.
  • the known techniques optimally require long interaction lengths, that is to say a long optical path through the liquid.
  • the weak optical absorptions of typical concentrations of pollutants in water mean that the total absorption of light in a cell of, for example, 10mm or 40mm length is relatively small. This limits the resolution of the instrument and hence the ability of the instrument to detect pollutants.
  • an instrument for monitoring characteristics of a liquid comprising means for forming an unsupported thread of the liquid, a source of radiation for producing a beam of radiation to which the liquid is transparent, means for directing the beam into the thread such that the beam is guided along the length of the thread by total internal reflection, and a detector for detecting components of the beam that are affected by variations in characteristics of the liquid defining the thread.
  • the present invention also provides a method for monitoring characteristics of a liquid, wherein an unsupported thread of the liquid is formed, a beam of radiation is produced to which the liquid is transparent, the beam is directed into the thread such that the beam is guided along the length of the thread by total internal reflection, and components of the beam that are affected by variations in characteristics of the liquid defining the thread are detected.
  • the thread may be formed as a freely falling jet issuing from, for example, an aperture in a container, or as a pressurised jet.
  • the thread may be caused to impinge upon a transparent window, the detector being mounted directly behind the window or optically coupled to the window.
  • the detector may be arranged to detect components of the beam that are back-scattered by the thread of liquid.
  • the thread may be in the form of an upper thread of the liquid to be monitored within a sheath of liquid of lower refractive index.
  • the beam may be directed into the thread through a window in contact with the liquid, or alternatively may be directed into the thread through a free surface of the liquid.
  • Fig. 1 illustrates a first embodiment of the present invention
  • Fig. 2 illustrates a modification of the first embodiment of the invention shown in Fig. 1;
  • Fig. 3 illustrates a second embodiment of the present invention.
  • a liquid such as water is introduced into a header tank 1 through an inlet 2.
  • An upper surface of the header tank is provided with an optically transparent window 3 above which an optical source 4 is located.
  • Coupling optics represented by a lens 5 produce a beam focused on an aperture 6 in the base of the header tank.
  • Water within the header tank falls from the aperture 6 in the form of a continuous thread 7.
  • the cross section of the thread 7 will not be stable, but nevertheless will be capable of transmitting the beam coupled into it along its length.
  • the thread 7 impinges upon a window 8 on the rear surface of which is mounted a detector 9.
  • the detector 9 detects the beam transmitted along the length of the thread 7 and thus enables characteristics of the water making up the thread to be determined.
  • the instrument described in Fig. 1 enables an optical beam to be guided along a path defined by the water which is of substantial length, for example 150mm.
  • the described arrangement has an input numerical aperture of greater than 0.5.
  • the water thread was simply formed by allowing water to exit through the aperture 6. For any such thread there is a length beyond which there is a high occurrence of break-up of the thread into droplets. Useful lengths of thread can, however, be readily produced.
  • the thread is produced simply by relying upon gravity but it will be appreciated that the thread could be formed as a pressurised jet by appropriate pressurisation of the header tank, for example.
  • the detector may be remote from the window 8.
  • the window 8 could be replaced by a prism 10 and an optical system in the form of, for example, a lens 11, could be used to focus light emerging from the prism onto a detector.
  • the detector could be of any appropriate form, for example a spectrometer or photometer.
  • an optical beam is focused by a lens 13 onto an aperture 14 defined in an open header tank 15 to which water is supplied through an inlet 16.
  • the beam is generated from an optical source 17, the output of which is transmitted to the lens 13 through a beam splitter 18.
  • a thread of water 19 is formed beneath the aperture 14 and light from the source is coupled into the thread. Rather than causing the thread to impinge upon a window to enable detection of light transmitted along its length, however, in the arrangement of Fig. 3 light back-scattered within the thread 19 is coupled via the lens 13 and the beam splitter 18 to a detector 20. Given that light is delivered to the thread 19 through a free surface of the liquid and returned to the detector through that same free surface, there is no optical surface in contact with the water and hence no problem with surface fouling.
  • the system may rely upon the Raman effect, that is an input excitation beam of high power causes the formation of a frequency- shifted beam due to scattering of the input beam off dissolved molecules with Raman-active mechanical vibrations.
  • frequency- shifted photons are emitted isotropically, and hence can be detected after travelling back along the thread of water.
  • the beam ⁇ splitter arrangement enables the instrument to perform a Raman scattering measurement without any optical component being required in contact with the water.
  • the water-guided arrangement of embodiments of the present invention is optically very efficient.
  • the strength of the returned Raman signal is dependent on the collection efficiency of the optical system.
  • the collection efficiency increases in proportion to the square of the guided wave numerical aperture.
  • the numerical aperture is given by the square root of the difference between the squares of the refractive index of the water and the refractive index of the surrounding air. If water was guided through a simple capillary, a numerical aperture of the order of 0.12 could be expected. In the case of water "guided" in air, however, given the large difference between the refractive indices of water and air, a numerical aperture of 0.87 can be expected.
  • the water thread therefore, has a captive efficiency of scattered photons greater than that of a glass fibre system by a factor of the order of 50.
  • the liquid to be monitored is the sole component of the thread into which radiation is directed. If the liquid is heavily contaminated with particles the liquid/air interface will be irregular, affecting the optical properties of the thread, because of surface tension effects.
  • a more regular surface for the thread of liquid to be monitored could be achieved by forming an inner thread of the liquid to be monitored inside a sheath of another liquid having a lower refractive index than that of the liquid to be monitored.
  • the lower refractive index could be achieved by using a different liquid for the sheath, or by other means, for example by having a temperature differential between the inner thread and the sheath. In such an arrangement, light will be guided down the inner thread without optical contact with a liquid/air surface. Additionally, it would be easier to establish a stable long thread if the volume of liquid making up the thread is increased by adding a sheath to the inner thread.
  • the present invention provides the following advantages: a) a long optical path length can be achieved without critical alignment problems. b) fouling problems can be significantly reduced by avoiding contact between optical surfaces and the liquid to be analysed, particularly in back-reflection mode in which completely optical window-less operation can be achieved. c) optical systems can be arranged to provide high numerical aperture. d) optical syst ems can be arranged to ensure a very high efficiency capture of scattered light.

Landscapes

  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

L'invention se rapporte à un instrument de mesure optique destiné à contrôler les caractéristiques d'un liquide tel que de l'eau. Un faisceau optique est généré et dirigé dans le filet (7) de liquide de sorte que le faisceau soit guidé le long du filet par réflexion interne totale. Des composantes du faisceau qui subissent l'influence des variations des caractéristiques du liquide constituant le filet sont détectées. Ces composantes peuvent être dérivées du filet lorsque celui-ci entre en collision avec une fenêtre (8) derrière laquelle est placé le détecteur (9) ou lors de la détection des composantes du faisceau rétrodiffusées. Il peut y avoir des interactions relativement longues entre le faisceau et le liquide.
PCT/GB1995/002727 1994-11-23 1995-11-23 Instrument optique WO1996016326A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB9710452A GB2310282B (en) 1994-11-23 1995-11-23 Optical instrument
AU38781/95A AU3878195A (en) 1994-11-23 1995-11-23 Optical instrument

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9423618A GB9423618D0 (en) 1994-11-23 1994-11-23 Optical instrument
GB9423618.9 1994-11-23

Publications (1)

Publication Number Publication Date
WO1996016326A1 true WO1996016326A1 (fr) 1996-05-30

Family

ID=10764837

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1995/002727 WO1996016326A1 (fr) 1994-11-23 1995-11-23 Instrument optique

Country Status (3)

Country Link
AU (1) AU3878195A (fr)
GB (2) GB9423618D0 (fr)
WO (1) WO1996016326A1 (fr)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997036167A1 (fr) * 1996-03-26 1997-10-02 United Utilities Plc Instrument optique
WO1999030832A1 (fr) * 1997-12-17 1999-06-24 Universidad De Sevilla Microjet capillaire stabilise et dispositifs et procedes pour produire ce microjet
US6119953A (en) * 1996-05-13 2000-09-19 Aradigm Corporation Liquid atomization process
US6187214B1 (en) 1996-05-13 2001-02-13 Universidad De Seville Method and device for production of components for microfabrication
US6189803B1 (en) 1996-05-13 2001-02-20 University Of Seville Fuel injection nozzle and method of use
US6196525B1 (en) 1996-05-13 2001-03-06 Universidad De Sevilla Device and method for fluid aeration via gas forced through a liquid within an orifice of a pressure chamber
US6299145B1 (en) 1996-05-13 2001-10-09 Universidad De Sevilla Device and method for fluid aeration via gas forced through a liquid within an orifice of a pressure chamber
US6386463B1 (en) 1996-05-13 2002-05-14 Universidad De Sevilla Fuel injection nozzle and method of use
US6405936B1 (en) 1996-05-13 2002-06-18 Universidad De Sevilla Stabilized capillary microjet and devices and methods for producing same
US6450189B1 (en) 1998-11-13 2002-09-17 Universidad De Sevilla Method and device for production of components for microfabrication
US6595202B2 (en) 1996-05-13 2003-07-22 Universidad De Sevilla Device and method for creating aerosols for drug delivery
US6792940B2 (en) 1996-05-13 2004-09-21 Universidad De Sevilla Device and method for creating aerosols for drug delivery

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105300958B (zh) * 2015-11-30 2018-01-23 齐齐哈尔医学院 长光程激光拉曼光谱气体传感器

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4477186A (en) * 1981-01-14 1984-10-16 Bifok Ab Photometric cuvette
DE3405592A1 (de) * 1984-02-16 1985-08-14 Siemens AG, 1000 Berlin und 8000 München Anordnung zur photometrischen konzentrationsbestimmung organischer und anorganischer stoffe
DE3704960A1 (de) * 1987-02-17 1988-08-25 Gebhard Birkle Verfahren zum optischen abtasten eines objektes und vorrichtung zur durchfuehrung des verfahrens

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT380525B (de) * 1983-02-21 1986-06-10 Muehle Manfred Ecksprosse fuer fenster-, tuer- oder wandkonstruktionen

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4477186A (en) * 1981-01-14 1984-10-16 Bifok Ab Photometric cuvette
DE3405592A1 (de) * 1984-02-16 1985-08-14 Siemens AG, 1000 Berlin und 8000 München Anordnung zur photometrischen konzentrationsbestimmung organischer und anorganischer stoffe
DE3704960A1 (de) * 1987-02-17 1988-08-25 Gebhard Birkle Verfahren zum optischen abtasten eines objektes und vorrichtung zur durchfuehrung des verfahrens

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6137571A (en) * 1996-03-26 2000-10-24 United Utilities Plc Optical instrument
WO1997036167A1 (fr) * 1996-03-26 1997-10-02 United Utilities Plc Instrument optique
US6386463B1 (en) 1996-05-13 2002-05-14 Universidad De Sevilla Fuel injection nozzle and method of use
US7059319B2 (en) 1996-05-13 2006-06-13 Universidad De Sevilla Device and method for creating aerosols for drug delivery
US6116516A (en) * 1996-05-13 2000-09-12 Universidad De Sevilla Stabilized capillary microjet and devices and methods for producing same
US6174469B1 (en) 1996-05-13 2001-01-16 Universidad De Sevilla Device and method for creating dry particles
US6187214B1 (en) 1996-05-13 2001-02-13 Universidad De Seville Method and device for production of components for microfabrication
US6189803B1 (en) 1996-05-13 2001-02-20 University Of Seville Fuel injection nozzle and method of use
US6197835B1 (en) 1996-05-13 2001-03-06 Universidad De Sevilla Device and method for creating spherical particles of uniform size
US6196525B1 (en) 1996-05-13 2001-03-06 Universidad De Sevilla Device and method for fluid aeration via gas forced through a liquid within an orifice of a pressure chamber
US6234402B1 (en) 1996-05-13 2001-05-22 Universidad De Sevilla Stabilized capillary microjet and devices and methods for producing same
US6241159B1 (en) 1996-05-13 2001-06-05 Universidad De Sevilla Liquid atomization procedure
US6299145B1 (en) 1996-05-13 2001-10-09 Universidad De Sevilla Device and method for fluid aeration via gas forced through a liquid within an orifice of a pressure chamber
US6357670B2 (en) 1996-05-13 2002-03-19 Universidad De Sevilla Stabilized capillary microjet and devices and methods for producing same
US6119953A (en) * 1996-05-13 2000-09-19 Aradigm Corporation Liquid atomization process
US8733343B2 (en) 1996-05-13 2014-05-27 Universidad De Sevilla Device and method for creating aerosols for drug delivery
US6554202B2 (en) 1996-05-13 2003-04-29 Universidad De Sevilla Fuel injection nozzle and method of use
US6432148B1 (en) 1996-05-13 2002-08-13 Universidad De Sevilla Fuel injection nozzle and method of use
US7293559B2 (en) 1996-05-13 2007-11-13 Universidad De Sevilla Device and method for creating aerosols for drug delivery
US6464886B2 (en) 1996-05-13 2002-10-15 Universidad De Sevilla Device and method for creating spherical particles of uniform size
US6405936B1 (en) 1996-05-13 2002-06-18 Universidad De Sevilla Stabilized capillary microjet and devices and methods for producing same
US6557834B2 (en) 1996-05-13 2003-05-06 Universidad De Seville Device and method for fluid aeration via gas forced through a liquid within an orifice of a pressure chamber
US6595202B2 (en) 1996-05-13 2003-07-22 Universidad De Sevilla Device and method for creating aerosols for drug delivery
US6792940B2 (en) 1996-05-13 2004-09-21 Universidad De Sevilla Device and method for creating aerosols for drug delivery
US6394429B2 (en) 1996-05-13 2002-05-28 Universidad De Sevilla Device and method for fluid aeration via gas forced through a liquid within an orifice of a pressure chamber
US7059321B2 (en) 1996-05-13 2006-06-13 Universidad De Sevilla Device and method for creating aerosols for drug delivery
WO1999030832A1 (fr) * 1997-12-17 1999-06-24 Universidad De Sevilla Microjet capillaire stabilise et dispositifs et procedes pour produire ce microjet
US6450189B1 (en) 1998-11-13 2002-09-17 Universidad De Sevilla Method and device for production of components for microfabrication

Also Published As

Publication number Publication date
GB9423618D0 (en) 1995-01-11
GB9710452D0 (en) 1997-07-16
GB2310282A (en) 1997-08-20
GB2310282B (en) 1999-01-06
AU3878195A (en) 1996-06-17

Similar Documents

Publication Publication Date Title
JP2911877B2 (ja) 懸濁液の散乱光或いは蛍光を検出するためのファイバー検出器
CN1900696B (zh) 空芯光子晶体光纤气体传感器
US7595882B1 (en) Hollow-core waveguide-based raman systems and methods
WO1996016326A1 (fr) Instrument optique
US8536542B2 (en) Flow cytometry analysis across optical fiber
US5642193A (en) Particle counter employing a solid-state laser with an intracavity view volume
US4728190A (en) Device and method for optically detecting particles in a fluid
RU94019480A (ru) Способ и устройство определения измерительного параметра/ов/ объекта
CN110268238A (zh) 扩散角测定装置、扩散角测定方法、激光装置以及激光系统
Archibald et al. Raman spectroscopy over optical fibers with the use of a near-IR FT spectrometer
US4236904A (en) Method for monitoring optical fiber drawing
CN119246387B (zh) 一种颗粒检测装置
US6894779B2 (en) Apparatus for detecting back-scatter in a laser-based blood analysis system
JP6364305B2 (ja) 水素ガス濃度計測装置および方法
CN204374087U (zh) 一种基于液芯波导的拉曼光谱测试系统
CN110567934A (zh) 一种基于微结构光纤的拉曼测试辅助调节耦合的实时成像系统及测试方法
JPS6146773B2 (fr)
KR900700871A (ko) 유체 오염 모니터
JP2020020794A (ja) 粒子を分析するための装置および方法
US11415859B2 (en) Methods and apparatus for detecting nitric oxide
CN211206261U (zh) 一种基于微结构光纤的拉曼测试辅助调节耦合的实时成像系统
KR20230079370A (ko) 연소 구역 화학 감지 시스템 및 연관된 방법
CN113711008A (zh) 用于粒子测试的装置和方法
KR101440119B1 (ko) 광섬유를 이용한 플라즈마 확산 속도 측정 장치 및 방법
JPH06300685A (ja) ガス検知器

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU BB BG BR BY CA CH CN CZ DE DK EE ES FI GB GE HU IS JP KE KG KP KR KZ LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TT UA UG US UZ VN

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
DPE2 Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101)