WO1994010595A1 - Confocal microscope and endoscope - Google Patents

Confocal microscope and endoscope Download PDF

Info

Publication number
WO1994010595A1
WO1994010595A1 PCT/AU1993/000534 AU9300534W WO9410595A1 WO 1994010595 A1 WO1994010595 A1 WO 1994010595A1 AU 9300534 W AU9300534 W AU 9300534W WO 9410595 A1 WO9410595 A1 WO 9410595A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
optical fibre
fibre bundle
scanning
lens
Prior art date
Application number
PCT/AU1993/000534
Other languages
French (fr)
Inventor
Roger Graham King
Peter Maxwell Delaney
Martin Russell Harris
Original Assignee
Monash University
H.B.H. Technological Industries Pty. 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 Monash University, H.B.H. Technological Industries Pty. Ltd. filed Critical Monash University
Priority to AU53303/94A priority Critical patent/AU669760B2/en
Priority to US08/424,320 priority patent/US5659642A/en
Publication of WO1994010595A1 publication Critical patent/WO1994010595A1/en

Links

Classifications

    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B21/00Microscopes
    • G02B21/0004Microscopes specially adapted for specific applications
    • G02B21/002Scanning microscopes
    • G02B21/0024Confocal scanning microscopes (CSOMs) or confocal "macroscopes"; Accessories which are not restricted to use with CSOMs, e.g. sample holders
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B21/00Microscopes
    • G02B21/0004Microscopes specially adapted for specific applications
    • G02B21/002Scanning microscopes
    • G02B21/0024Confocal scanning microscopes (CSOMs) or confocal "macroscopes"; Accessories which are not restricted to use with CSOMs, e.g. sample holders
    • G02B21/0028Confocal scanning microscopes (CSOMs) or confocal "macroscopes"; Accessories which are not restricted to use with CSOMs, e.g. sample holders specially adapted for specific applications, e.g. for endoscopes, ophthalmoscopes, attachments to conventional microscopes
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B21/00Microscopes
    • G02B21/0004Microscopes specially adapted for specific applications
    • G02B21/002Scanning microscopes
    • G02B21/0024Confocal scanning microscopes (CSOMs) or confocal "macroscopes"; Accessories which are not restricted to use with CSOMs, e.g. sample holders
    • G02B21/0036Scanning details, e.g. scanning stages
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B23/00Telescopes, e.g. binoculars; Periscopes; Instruments for viewing the inside of hollow bodies; Viewfinders; Optical aiming or sighting devices
    • G02B23/24Instruments or systems for viewing the inside of hollow bodies, e.g. fibrescopes
    • G02B23/26Instruments or systems for viewing the inside of hollow bodies, e.g. fibrescopes using light guides
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/04Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings formed by bundles of fibres
    • G02B6/06Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings formed by bundles of fibres the relative position of the fibres being the same at both ends, e.g. for transporting images
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24Coupling light guides
    • G02B6/26Optical coupling means
    • G02B6/28Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/2804Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers

Definitions

  • This invention relates to a microscope and more particularly to a microscope using the principal of confocal microscopy.
  • confocal microscopy The principal of confocal microscopy was disclosed in U.S. patent 3,013,467 to Minsky in 1957.
  • a point or spot (which may be diffraction- limited) within an object is illuminated and only light from that point is imaged, e.g. via a pin hole detector.
  • a clear image By scanning the spot across a plane (e.g. with a translucent object) a clear image (“optical section”) may be obtained.
  • the present invention relates to an improvement to confocal microscopes of the type described in the above mentioned International applications and which are particularly suited to produce images inside of the living body of animals or humans.
  • the invention may be said to reside in a confocal microscope comprising: a light source; an optical fibre bundle for receiving light from the light source and for transmitting the light to an object; and for allowing light to return from the object through the optical fibre bundle; switching means for selectively switching selected fibres in the optical fibre bundle so as to allow light to selectively be transmitted and returned through respective fibres in the optical fibre bundle; and a detector for receiving returned light from the optical fibre bundle to enable an image of the object to be produced.
  • switching means which enables the individual fibres in the bundle to be selectively switched to allow light to be transmitted through them enables selected fibres to be switched in sequence so that light is scanned across the focal plane on or within the object and light returning confocally from the object can be detected virtually instantaneously on its return from the object.
  • Another alternative which could be particularly useful for real time imaging of fluorescent objects, is to generate an identical pattern of switching of the switch means which lags the original pattern so that light may be detected confocally a short time after it has illuminated the object. This is because peak fluorescence occurs at a time after illumination of an object.
  • the switching means comprises a plurality of switchable optical fibre or waveguide tree couplers, the plurality of tree couplers having a first end which receives light from a first light path and a plurality of second ends which are coupled to or integral with respective fibres of the fibre bundle.
  • the switching means comprises a plurality of switches in the respective fibres of the optical fibre bundle.
  • an optical element is provided at an image end of the optical fibre bundle for simultaneously launching light to the individual fibres of the optical fibre bundle and for collecting return light from the optical fibre bundle.
  • a beam splitter or directional coupler is disposed proximal to the optical fibre bundle, for receiving light from the light source and transmitting the light to the optical fibre bundle, and for receiving return light from the optical fibre bundle and for transmitting the light to the light detector.
  • the first light path comprises one or more optical fibres.
  • the first light path could comprise a beam path with or without beam steering optics rather than, or as well as at least one optical fibre.
  • a lens element or lens array is provided between the object and the distal end of the optical fibre bundle.
  • a further aspect of the invention concerns a scanning head which may be used in a confocal microscope.
  • This aspect of the invention may be said to reside in a scanning head for receiving light from a light source and for transmitting return light to a detector, the scanning head comprising: a scanning means for causing a beam of light to scan an object; a beam steering lens for focussing the light, the beam steering lens being displaced from an image plane at which the light focuses; and an objective lens for focussing the light on or in an object.
  • this aspect of the invention utilises a beam steering lens which is displaced from the image plane scanning is performed asymmetrically (i.e. so that the lens is proximal to the image plane) thus eliminating detection of lens reflections.
  • the scanning head may be dimensioned to fall within the range for minimum errors in scanning and flatness of field, without introducing added optics to correct for mirror separation.
  • a fibre output lens is arranged between the light source and the scanning means for focussing (in combination with the beam steering lens) the light beam at the image plane.
  • the fibre output lens may be a standard microscope objective element, configured for its specific tube length, hence retaining resolution performance.
  • the image plane is on the object side of the beam steering lens such that the scanning head is the optical analogue of an eye piece, compatible with standard microscopes.
  • the scanning means comprises one or more scanning mirrors.
  • other scanning devices such as acousto-optical devices could be utilised.
  • At least one optical fibre is provided between the light source and the fibre output lens for transmitting light from the light source to the fibre output lens.
  • a beam splitter or directional coupler is provided for directing the light from the light source to the scanning means and for directing return light from the scanning means to the light detector.
  • Figure 1 is a view of a first embodiment of the invention
  • Figure 2 is a view of the second embodiment of the invention.
  • Figure 2A is a diagram illustrating control of the embodiments of figures 1 and 2; and Figure 3 is a view of a scanning head according to a further aspect of the invention.
  • the confocal microscope comprises a light source 10 and a detector 12.
  • the detector 12 may be coupled to a computerised image generator 14 for enabling an image of an object 16 to be formed on a television screen or the like.
  • the light source 10 is coupled to a beam splitter or directional coupler 18 by a first optical fibre 20 and the light detector 12 is connected to the beam splitter or directional coupler 18 by a second optical fibre 22.
  • the beam splitter or directional coupler 18 is connected to an array of switched optical fibre or waveguide tree couplers 24.
  • the array of switched tree couplers 24 comprises a first tree coupler 24 ' which has a first end 24a and a plurality of branches 24b which have second ends 24c.
  • the first tree coupler 24' has one fibre or connection in and "n" fibres or connections out.
  • the first tree coupler may then be linked to a plurality of further tree couplers 24 ' ' and if necessary the second ends of the further tree couplers 24 ' ' may be yet connected to further tree couplers until the number of outputs from the array of tree couplers can be linked to (or form an integral part of) respective fibres in an optical fibre bundle 30 which includes a plurality of individual optical fibres (not shown) .
  • each individual optical fibre is connected to the output end of the array of tree couplers 24.
  • the tree couplers are switchable to enable light to pass through selected branches of the optical fibre or waveguide tree couplers so that light can be launched into selected individual optical fibres in the optical fibre bundle 30.
  • a lens or lens array 32 is arranged at the distal or object end of the optical fibre bundle 30 for focussing the light transmitted through the optical fibre bundle on or in the object 16.
  • the return light from the object 16 which returns confocally from the object 16 may traverse the same pathway, as far as the beam splitter or directional coupler 18.
  • the beam splitter or directional coupler 18 then directs the beam through the second optical fibre 22 to the light detector 12 for formation of an image of the object.
  • the image is generated by the light detector 12 and image generator 14 by switching the tree couplers 24' , 24' ' in such a way that light is scanned across the focal plane on or within the object 16.
  • Light returning confocally from the object can be detected virtually instantaneously after it has traversed the same pathway, as far as the beam splitter 18, on its return from the object or alternatively, an identical pattern of switching in the tree couplers 24', 24'' can be generated which lags the original pattern so that light may be detected confocally a short time after it has illuminated the object.
  • This technique is useful in real-time imaging of fluorescence objects because peak fluorescence occurs at a finite time after illumination of an object.
  • the light emerging from the distal end of the fibre bundle 30 may be diffraction limited.
  • optical fibres 20 or 22 could be replaced by a path with or without beam steering optics to form the first light path instead of using optical fibres.
  • Figure 2 shows a second embodiment of the invention in which like elements are represented by the same reference numerals to those in figure 1.
  • the optical fibre bundle 30 is provided with fibre on-off switches 34 in the individual fibres of the optical fibre bundle so that the switches are effectively integral with the individual fibres in the bundle thereby doing away with the need for an array of switched tree couplers.
  • Optical elements 36 such as lenses or the like may be provided at the proximal end of the optical fibre bundle 30 to simultaneously launch light into the individual optical fibres of the optical fibre bundle 30 which is received from the beam splitter or directional coupler 18.
  • the in-fibre on-off switches 34 may be optical, optoacoustic or electro-optic or other type of switches which either prevent, preferably with minimal reflection, or allow light to pass down a particular fibre.
  • An example of in-fibre switching is given by Lytel-R. (1990) "Applications of Electro-optic Polymers to Integrated Optics", S.P.I.E., 1216, 30.
  • in-fibre switching at any one moment in time, light is allowed to pass down one or even several fibres of the bundle.
  • a fibre in the optical fibre bundle 30 After light emerges from the distal end of a fibre in the optical fibre bundle 30 it is focussed on a point or spot on or within the object 16 and light returning confocally from the object may traverse the same pathway, as far as the beam splitter or directional coupler 18.
  • scanning of light across the focal plane of the object may be achieved.
  • the light may return from the object by the same path almost instantaneously or, as described above, the in-fibre switching may lag the original switching pattern.
  • the movement could be either of the fibre bundle tip or of the object or of both.
  • three optical fibres 30a, 30b and 30c of the optical fibre bundle 30 which including a optical, optoacoustic, electro-optic or other type of switch 31 which are electrically, optically or otherwise connected to a controller 33 (such as a computer or the like) for example by leads or connectors 35.
  • the controller could control optical switches by sending light to those switches (eg through the fibre optic bundle or array of tree couplers) .
  • the controller 33 applies output signals to the switches 31 to control the switches so that the switches either allow or prevent light to pass through the optical fibre 30a, 30b and 30c.
  • a similar arrangement to that shown above may be used to control the switchable optical fibre or waveguide tree couplers described with reference to figure 1.
  • switchable waveguide tree couplers could form part of an integrated chip with optical and electronic components.
  • Figure 3 discloses a scanning head which is particularly useful in non-endoscopic applications of the microscope.
  • the scanning head comprises a head 42 which contains one or more scanning mirrors 44 and a fibre output lens 46 which receives light from an optical fibre or point source 48.
  • the optical fibre or point source 48 is coupled to a beam splitter or directional coupler 50 which in turn is coupled to a light source 52 and light detector 54 by individual optical pathways or waveguides (such as optical fibres) 56 and 58.
  • the head 42 includes a beam steering lens 60.
  • the beam steering lens 60 is displaced axially from an image plane of the lens 62 so that scanning is performed asymmetrically (i.e. so that the lens 60 is proximal to the image plane) thus eliminating detection of lens reflections.
  • a microscope objective lens 62 is provided for focussing the light from the light source 52 on or in an object. Return light from the object is returned along the same path as the incident light as far as beam splitter 50 and is directed by beam splitter 50 to light detector 54 via pathway 58 for formation of an image.
  • the scanning head performs scanning asymmetrically in relation to the beam steering lens 60 problems inherent in symmetrical designs in which there may be problems of confocal return from the lens and aberrations due to the lens elements being at suboptimal separations are eliminated.
  • the fibre output lens 46 is a standard microscope objective element, configured for its specified tube length, hence retaining resolution performance.
  • the image is projected below the beam steering lens such that the scanning head is the optical analogue of an eyepiece, compatible with standard microscopes.
  • the dimensions achieved fall within the range of minimum errors in scanning and flatness of field, without introducing added optics to correct for minor separation.

Abstract

A confocal microscope and a scanning head are disclosed. The microscope comprises a light source (10) and a detector (12). An optical fibre bundle (24) receives light from the light source (10) and transmits the light source to an object and allows light to return from the object. Switchable optical fibre or waveguide tree couplers (24b, 24c) selectively switch fibres in the optical fibre bundle to allow light to be transmitted and returned through the fibre bundle (24). A detector (12) detects the returned light to enable an image of the object to be produced. The scanning head includes scanning mirrors (44) for enabling a beam of light to scan an object, a beam steering lens (60) is located at a position displaced from an image plane and an objective lens (62) is provided for focussing light on or in an object.

Description

CONFOCAL MICROSCOPE AND ENDOSCOPE
This invention relates to a microscope and more particularly to a microscope using the principal of confocal microscopy.
The principal of confocal microscopy was disclosed in U.S. patent 3,013,467 to Minsky in 1957. With confocal microscopy, a point or spot (which may be diffraction- limited) within an object is illuminated and only light from that point is imaged, e.g. via a pin hole detector. By scanning the spot across a plane (e.g. with a translucent object) a clear image ("optical section") may be obtained.
International patent applications PCT/AU89/00298 and PCT/AU91/00129 describe the design of confocal microscopes which instead of a pin hole (or equivalent) of a conventional confocal microscope use an optical fibre or fibre bundle, thus allowing the distal end to be more freely mobile, transportable and miniaturisable.
The present invention relates to an improvement to confocal microscopes of the type described in the above mentioned International applications and which are particularly suited to produce images inside of the living body of animals or humans.
The invention may be said to reside in a confocal microscope comprising: a light source; an optical fibre bundle for receiving light from the light source and for transmitting the light to an object; and for allowing light to return from the object through the optical fibre bundle; switching means for selectively switching selected fibres in the optical fibre bundle so as to allow light to selectively be transmitted and returned through respective fibres in the optical fibre bundle; and a detector for receiving returned light from the optical fibre bundle to enable an image of the object to be produced.
The use of switching means which enables the individual fibres in the bundle to be selectively switched to allow light to be transmitted through them enables selected fibres to be switched in sequence so that light is scanned across the focal plane on or within the object and light returning confocally from the object can be detected virtually instantaneously on its return from the object. Another alternative which could be particularly useful for real time imaging of fluorescent objects, is to generate an identical pattern of switching of the switch means which lags the original pattern so that light may be detected confocally a short time after it has illuminated the object. This is because peak fluorescence occurs at a time after illumination of an object.
Preferably the switching means comprises a plurality of switchable optical fibre or waveguide tree couplers, the plurality of tree couplers having a first end which receives light from a first light path and a plurality of second ends which are coupled to or integral with respective fibres of the fibre bundle.
In a further embodiment the switching means comprises a plurality of switches in the respective fibres of the optical fibre bundle.
In this embodiment of the invention an optical element is provided at an image end of the optical fibre bundle for simultaneously launching light to the individual fibres of the optical fibre bundle and for collecting return light from the optical fibre bundle.
Preferably a beam splitter or directional coupler is disposed proximal to the optical fibre bundle, for receiving light from the light source and transmitting the light to the optical fibre bundle, and for receiving return light from the optical fibre bundle and for transmitting the light to the light detector.
Preferably the first light path comprises one or more optical fibres. However, in other embodiments the first light path could comprise a beam path with or without beam steering optics rather than, or as well as at least one optical fibre.
Preferably a lens element or lens array is provided between the object and the distal end of the optical fibre bundle.
A further aspect of the invention concerns a scanning head which may be used in a confocal microscope.
This aspect of the invention may be said to reside in a scanning head for receiving light from a light source and for transmitting return light to a detector, the scanning head comprising: a scanning means for causing a beam of light to scan an object; a beam steering lens for focussing the light, the beam steering lens being displaced from an image plane at which the light focuses; and an objective lens for focussing the light on or in an object.
Since this aspect of the invention utilises a beam steering lens which is displaced from the image plane scanning is performed asymmetrically (i.e. so that the lens is proximal to the image plane) thus eliminating detection of lens reflections. Furthermore, the scanning head may be dimensioned to fall within the range for minimum errors in scanning and flatness of field, without introducing added optics to correct for mirror separation.
Preferably a fibre output lens is arranged between the light source and the scanning means for focussing (in combination with the beam steering lens) the light beam at the image plane. The fibre output lens may be a standard microscope objective element, configured for its specific tube length, hence retaining resolution performance.
Preferably the image plane is on the object side of the beam steering lens such that the scanning head is the optical analogue of an eye piece, compatible with standard microscopes.
Preferably the scanning means comprises one or more scanning mirrors. However, in other embodiments other scanning devices such as acousto-optical devices could be utilised.
Preferably at least one optical fibre is provided between the light source and the fibre output lens for transmitting light from the light source to the fibre output lens. Preferably a beam splitter or directional coupler is provided for directing the light from the light source to the scanning means and for directing return light from the scanning means to the light detector.
Preferred embodiments of the invention will be described, by way of example, with reference to the accompanying drawings in which:
Figure 1 is a view of a first embodiment of the invention;
Figure 2 is a view of the second embodiment of the invention;
Figure 2A is a diagram illustrating control of the embodiments of figures 1 and 2; and Figure 3 is a view of a scanning head according to a further aspect of the invention.
With reference to figure 1 the confocal microscope comprises a light source 10 and a detector 12. The detector 12 may be coupled to a computerised image generator 14 for enabling an image of an object 16 to be formed on a television screen or the like.
The light source 10 is coupled to a beam splitter or directional coupler 18 by a first optical fibre 20 and the light detector 12 is connected to the beam splitter or directional coupler 18 by a second optical fibre 22.
The beam splitter or directional coupler 18 is connected to an array of switched optical fibre or waveguide tree couplers 24. The array of switched tree couplers 24 comprises a first tree coupler 24 ' which has a first end 24a and a plurality of branches 24b which have second ends 24c. Thus, the first tree coupler 24' has one fibre or connection in and "n" fibres or connections out. The first tree coupler may then be linked to a plurality of further tree couplers 24 ' ' and if necessary the second ends of the further tree couplers 24 ' ' may be yet connected to further tree couplers until the number of outputs from the array of tree couplers can be linked to (or form an integral part of) respective fibres in an optical fibre bundle 30 which includes a plurality of individual optical fibres (not shown) . Thus, each individual optical fibre is connected to the output end of the array of tree couplers 24.
The tree couplers are switchable to enable light to pass through selected branches of the optical fibre or waveguide tree couplers so that light can be launched into selected individual optical fibres in the optical fibre bundle 30.
A lens or lens array 32 is arranged at the distal or object end of the optical fibre bundle 30 for focussing the light transmitted through the optical fibre bundle on or in the object 16. The return light from the object 16 which returns confocally from the object 16 may traverse the same pathway, as far as the beam splitter or directional coupler 18. The beam splitter or directional coupler 18 then directs the beam through the second optical fibre 22 to the light detector 12 for formation of an image of the object.
The image is generated by the light detector 12 and image generator 14 by switching the tree couplers 24' , 24' ' in such a way that light is scanned across the focal plane on or within the object 16. Light returning confocally from the object can be detected virtually instantaneously after it has traversed the same pathway, as far as the beam splitter 18, on its return from the object or alternatively, an identical pattern of switching in the tree couplers 24', 24'' can be generated which lags the original pattern so that light may be detected confocally a short time after it has illuminated the object. This technique is useful in real-time imaging of fluorescence objects because peak fluorescence occurs at a finite time after illumination of an object.
The light emerging from the distal end of the fibre bundle 30 may be diffraction limited.
In an alternative arrangement to that shown in figure 1, the optical fibres 20 or 22 could be replaced by a path with or without beam steering optics to form the first light path instead of using optical fibres.
Figure 2 shows a second embodiment of the invention in which like elements are represented by the same reference numerals to those in figure 1. In this embodiment of the invention the optical fibre bundle 30 is provided with fibre on-off switches 34 in the individual fibres of the optical fibre bundle so that the switches are effectively integral with the individual fibres in the bundle thereby doing away with the need for an array of switched tree couplers. Optical elements 36 such as lenses or the like may be provided at the proximal end of the optical fibre bundle 30 to simultaneously launch light into the individual optical fibres of the optical fibre bundle 30 which is received from the beam splitter or directional coupler 18.
The in-fibre on-off switches 34 may be optical, optoacoustic or electro-optic or other type of switches which either prevent, preferably with minimal reflection, or allow light to pass down a particular fibre. An example of in-fibre switching is given by Lytel-R. (1990) "Applications of Electro-optic Polymers to Integrated Optics", S.P.I.E., 1216, 30.
By means of in-fibre switching, at any one moment in time, light is allowed to pass down one or even several fibres of the bundle. As in figure 1, after light emerges from the distal end of a fibre in the optical fibre bundle 30 it is focussed on a point or spot on or within the object 16 and light returning confocally from the object may traverse the same pathway, as far as the beam splitter or directional coupler 18. By an appropriate pattern of switching within the bundle 30, scanning of light across the focal plane of the object may be achieved. The light may return from the object by the same path almost instantaneously or, as described above, the in-fibre switching may lag the original switching pattern.
Because the resolution of the image will be limited by the gaps between the individual fibres in the optical fibre bundles 30, in figures 1 and 2 improved resolution may be obtained by movements (which could, for example, be quite small - e.g. of a similar magnitude as the distance between the adjacent fibres in the bundle) of the distal end of the optical fibre bundles 30 in relation to the object 16.
This would allow scanning in the focal plane of the object to be less discrete and more continuous in nature. The movement could be either of the fibre bundle tip or of the object or of both.
As is shown in figure 2A, three optical fibres 30a, 30b and 30c of the optical fibre bundle 30 which including a optical, optoacoustic, electro-optic or other type of switch 31 which are electrically, optically or otherwise connected to a controller 33 (such as a computer or the like) for example by leads or connectors 35. Alternatively the controller could control optical switches by sending light to those switches (eg through the fibre optic bundle or array of tree couplers) . The controller 33 applies output signals to the switches 31 to control the switches so that the switches either allow or prevent light to pass through the optical fibre 30a, 30b and 30c. A similar arrangement to that shown above may be used to control the switchable optical fibre or waveguide tree couplers described with reference to figure 1. Alternatively switchable waveguide tree couplers could form part of an integrated chip with optical and electronic components.
Figure 3 discloses a scanning head which is particularly useful in non-endoscopic applications of the microscope.
In figure 3 the scanning head comprises a head 42 which contains one or more scanning mirrors 44 and a fibre output lens 46 which receives light from an optical fibre or point source 48. The optical fibre or point source 48 is coupled to a beam splitter or directional coupler 50 which in turn is coupled to a light source 52 and light detector 54 by individual optical pathways or waveguides (such as optical fibres) 56 and 58.
The head 42 includes a beam steering lens 60. The beam steering lens 60 is displaced axially from an image plane of the lens 62 so that scanning is performed asymmetrically (i.e. so that the lens 60 is proximal to the image plane) thus eliminating detection of lens reflections. A microscope objective lens 62 is provided for focussing the light from the light source 52 on or in an object. Return light from the object is returned along the same path as the incident light as far as beam splitter 50 and is directed by beam splitter 50 to light detector 54 via pathway 58 for formation of an image.
Since the scanning head performs scanning asymmetrically in relation to the beam steering lens 60 problems inherent in symmetrical designs in which there may be problems of confocal return from the lens and aberrations due to the lens elements being at suboptimal separations are eliminated.
The fibre output lens 46 is a standard microscope objective element, configured for its specified tube length, hence retaining resolution performance. The image is projected below the beam steering lens such that the scanning head is the optical analogue of an eyepiece, compatible with standard microscopes. The dimensions achieved fall within the range of minimum errors in scanning and flatness of field, without introducing added optics to correct for minor separation.
Since modifications within the spirit and scope of the invention may readily be effected by persons skilled within the art, it is to be understood that this invention is not limited to the particular embodiment described by way of example hereinabove.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:
1. A confocal microscope comprising: a light source; an optical fibre bundle for receiving light from the light source and for transmitting the light to an object; and for allowing light to return from the object through the optical fibre bundle; switching means for selectively switching selected fibres in the optical fibre bundle so as to allow light to selectively be transmitted and returned through respective fibres in the optical fibre bundle; and a detector for receiving returned light from the optical fibre bundle to enable an image of the object to be produced.
2. The microscope of claim 1 wherein the switching means comprises a plurality of switchable optical fibre or waveguide tree couplers, the plurality of tree couplers having a first end which receives light from a first light path and a plurality of second ends which are coupled to or integral with respective fibres of the fibre bundle.
3. The microscope of claim 1 wherein the switching means comprises a plurality of switches in the respective fibres of the optical fibre bundle.
4. The microscope of claim 3 wherein an optical element is provided at an image end of the optical fibre bundle for simultaneously launching light to the individual fibres of the optical fibre bundle and for collecting return light from the optical fibre bundle.
5. The microscope of claim 1 wherein a beam splitter or directional coupler is disposed proximal to the optical fibre bundle, for receiving light from the light source and transmitting the light to the optical fibre bundle, and for receiving return light from the optical fibre bundle and for transmitting the light to the light detector.
6. The microscope of claim 1 wherein the first light path comprises one or more optical fibres.
7. The microscope of claim 1 wherein a lens element or lens array is provided between the object and the distal end of the optical fibre bundle.
8. A scanning head for receiving light from a light source and for transmitting return light to a detector, the scanning head comprising: a scanning means for causing a beam of light to scan an object; a beam steering lens for focussing the light, the beam steering lens being displaced from an image plane at which the light focuses; and an objective lens for focussing the light on or in an object.
9. The scanning head of claim 8 wherein a fibre output lens is arranged between the light source and the scanning means for focussing, in combination with the beam steering lens, the light beam at the image plane.
10. The scanning head of claim 8 wherein the image plane is on the object side of the beam steering lens such that the scanning head is the optical analogue of an eye piece, compatible with standard microscopes.
11. The scanning head of claim 8 wherein the scanning means comprises one or more scanning mirrors. However, in other embodiments other scanning devices such as acousto- optical devices could be utilised.
12. The scanning head of claim 8 wherein at least one optical fibre is provided between the light source and the fibre output lens for transmitting light from the light source to the fibre output lens.
13. The scanning head of claim 8 wherein a beam splitter or directional coupler is provided for directing the light from the light source to the scanning means and for directing return light from the scanning means to the light detector.
PCT/AU1993/000534 1992-10-23 1993-10-19 Confocal microscope and endoscope WO1994010595A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU53303/94A AU669760B2 (en) 1992-10-23 1993-10-19 Confocal microscope and endoscope
US08/424,320 US5659642A (en) 1992-10-23 1993-10-19 Confocal microscope and endoscope

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPL5462 1992-10-23
AUPL546292 1992-10-23

Publications (1)

Publication Number Publication Date
WO1994010595A1 true WO1994010595A1 (en) 1994-05-11

Family

ID=3776494

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AU1993/000534 WO1994010595A1 (en) 1992-10-23 1993-10-19 Confocal microscope and endoscope

Country Status (2)

Country Link
US (1) US5659642A (en)
WO (1) WO1994010595A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996030796A1 (en) * 1995-03-24 1996-10-03 Optiscan Pty. Ltd. Optical fibre confocal imager with variable near-confocal control
AU694005B2 (en) * 1995-03-24 1998-07-09 Optiscan Pty Limited Optical fibre confocal imager with variable near-confocal control
WO1999035527A1 (en) * 1998-01-12 1999-07-15 Wallac Oy Confocal microscope with plural scanning beams
EP1627248A2 (en) * 2003-05-29 2006-02-22 The Regents of the University of Michigan Double-clad fiber scanning microscope
WO2006076772A1 (en) * 2005-01-21 2006-07-27 Optiscan Pty Ltd Fibre bundle confocal endomicroscope

Families Citing this family (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050111089A1 (en) * 1994-07-15 2005-05-26 Baer Stephen C. Superresolving microscopy apparatus
US6016376A (en) * 1997-10-06 2000-01-18 Nec Research Institute, Inc. Tapered coherent fiber bundle imaging device for near-field optical microscopy
JP3863992B2 (en) * 1998-03-18 2006-12-27 オリンパス株式会社 Scanning optical microscope device
DE60022546T2 (en) * 1999-12-17 2006-06-22 Digital Optical Imaging Corp., Bellingham ILLUSTRATION METHOD AND DEVICE WITH LIGHT GUIDE BUNDLE AND SPATIAL LIGHT MODULATOR
US6663560B2 (en) * 1999-12-17 2003-12-16 Digital Optical Imaging Corporation Methods and apparatus for imaging using a light guide bundle and a spatial light modulator
US6530882B1 (en) 2000-06-30 2003-03-11 Inner Vision Imaging, L.L.C. Endoscope having microscopic and macroscopic magnification
US6450949B1 (en) 2000-06-30 2002-09-17 Inner Vision Imaging, Inc. Endoscope
JP2004505257A (en) * 2000-07-27 2004-02-19 ゼテティック・インスティチュート Multiple source arrays for confocal and near-field microscopy
DE10121064A1 (en) * 2001-04-28 2002-10-31 Evotec Ag Device and method for the optical measurement of chemical and / or biological samples
DE10220824B4 (en) * 2001-05-14 2010-08-05 Robert Bosch Gmbh Optical measuring device
FR2834349B1 (en) * 2001-12-28 2004-04-09 Mauna Kea Technologies CONFOCAL IMAGING APPARATUS ESPECIALLY FOR ENDOSCOPES
WO2003090613A1 (en) * 2002-04-26 2003-11-06 Optiscan Pty Ltd Laser scanning confocal microscope with fibre bundle return
US6998600B2 (en) 2003-06-30 2006-02-14 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Multifrequency ultra-high resolution miniature scanning microscope using microchannel and solid-state sensor technologies and method for scanning samples
EP1816949A1 (en) 2004-11-29 2007-08-15 The General Hospital Corporation Arrangements, devices, endoscopes, catheters and methods for performing optical imaging by simultaneously illuminating and detecting multiple points on a sample
HU227859B1 (en) * 2005-01-27 2012-05-02 E Szilveszter Vizi Real-time 3d nonlinear microscope measuring system and its application
DE102006034604A1 (en) * 2006-07-24 2008-01-31 Jenoptik Laser, Optik, Systeme Gmbh Optical system for surface measurement
DE102007009660A1 (en) * 2007-02-21 2008-08-28 Carl Zeiss Microimaging Gmbh Confocal laser microscope
US7566173B2 (en) * 2007-07-09 2009-07-28 Alcon, Inc. Multi-spot ophthalmic laser probe
US8644663B2 (en) * 2007-10-11 2014-02-04 Mauna Kea Technologies Modular imaging system, modules for this system and method implemented using this system
FR2922308B1 (en) * 2007-10-11 2012-03-16 Mauna Kea Technologies MODULAR IMAGING DEVICE, MODULE FOR THIS DEVICE AND METHOD IMPLEMENTED BY SAID DEVICE
TW200928598A (en) * 2007-12-24 2009-07-01 Ind Tech Res Inst Inclined exposure lithography system
US7903706B2 (en) * 2008-04-04 2011-03-08 O'shaughnessy John Compact, thermally stable multi-laser engine
US9413130B2 (en) 2012-12-12 2016-08-09 Cvi Laser, Llc Optical systems
US8975572B2 (en) 2008-04-04 2015-03-10 Cvi Laser, Llc Compact, thermally stable fiber-optic array mountable to flow cell
US10114213B2 (en) 2008-04-04 2018-10-30 Cvi Laser, Llc Laser systems and optical devices for manipulating laser beams
KR101610840B1 (en) * 2009-11-24 2016-04-08 알콘 리서치, 리미티드 Single-fiber multi-spot laser probe for ophthalmic endoillumination
AU2010332222B2 (en) * 2009-12-15 2014-11-20 Alcon Inc. Multi-spot laser probe
US10245181B2 (en) 2012-12-21 2019-04-02 Alcon Research, Ltd. Grin fiber multi-spot laser probe
DE102013012609A1 (en) * 2013-07-26 2015-01-29 Carl Zeiss Microscopy Gmbh Opto-electronic detector, in particular for high-resolution light scanning microscopes
US11378808B2 (en) 2018-07-18 2022-07-05 Idex Health & Science Llc Laser systems and optical devices for laser beam shaping
US11556068B2 (en) 2018-10-12 2023-01-17 Asml Netherlands B.V. Detection system for an alignment sensor

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2628543A1 (en) * 1976-05-28 1977-12-08 Bbc Brown Boveri & Cie Fibre optic high resolution optical scanner - has small dia. scan beam with transmit optic fibre coaxial with receive optic fibre bundle
US4410235A (en) * 1979-09-10 1983-10-18 Siemens Aktiengesellschaft Device for producing a moving light beam
EP0283256A2 (en) * 1987-03-18 1988-09-21 Tektronix Inc. Scanning optical microscope
WO1989003057A1 (en) * 1987-09-24 1989-04-06 Washington University Kit for converting a standard microscope into, and design for, a single aperture confocal scanning epi-illumination microscope
WO1990000754A1 (en) * 1988-07-13 1990-01-25 Martin Russell Harris Scanning confocal microscope
EP0418928A2 (en) * 1989-09-22 1991-03-27 Fuji Photo Film Co., Ltd. Scanning microscope and scanning mechanism for the same
WO1991015792A1 (en) * 1990-04-06 1991-10-17 Martin Russell Harris Confocal microscope
NL9001202A (en) * 1990-05-25 1991-12-16 Philips Nv Confocal detector scanning system for compact disc player - uses fibre=optic assembly in place of conventional pinhole diaphragm

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4856863A (en) * 1988-06-22 1989-08-15 Texas Instruments Incorporated Optical fiber interconnection network including spatial light modulator
US5037173A (en) * 1989-11-22 1991-08-06 Texas Instruments Incorporated Optical interconnection network
US5181134A (en) * 1991-03-15 1993-01-19 At&T Bell Laboratories Photonic cross-connect switch
JPH05300188A (en) * 1992-04-23 1993-11-12 Hitachi Ltd Parallel light transmitting device

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2628543A1 (en) * 1976-05-28 1977-12-08 Bbc Brown Boveri & Cie Fibre optic high resolution optical scanner - has small dia. scan beam with transmit optic fibre coaxial with receive optic fibre bundle
US4410235A (en) * 1979-09-10 1983-10-18 Siemens Aktiengesellschaft Device for producing a moving light beam
EP0283256A2 (en) * 1987-03-18 1988-09-21 Tektronix Inc. Scanning optical microscope
WO1989003057A1 (en) * 1987-09-24 1989-04-06 Washington University Kit for converting a standard microscope into, and design for, a single aperture confocal scanning epi-illumination microscope
WO1990000754A1 (en) * 1988-07-13 1990-01-25 Martin Russell Harris Scanning confocal microscope
EP0418928A2 (en) * 1989-09-22 1991-03-27 Fuji Photo Film Co., Ltd. Scanning microscope and scanning mechanism for the same
WO1991015792A1 (en) * 1990-04-06 1991-10-17 Martin Russell Harris Confocal microscope
NL9001202A (en) * 1990-05-25 1991-12-16 Philips Nv Confocal detector scanning system for compact disc player - uses fibre=optic assembly in place of conventional pinhole diaphragm

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996030796A1 (en) * 1995-03-24 1996-10-03 Optiscan Pty. Ltd. Optical fibre confocal imager with variable near-confocal control
AU694005B2 (en) * 1995-03-24 1998-07-09 Optiscan Pty Limited Optical fibre confocal imager with variable near-confocal control
US5926592A (en) * 1995-03-24 1999-07-20 Optiscan Pty Ltd Optical fibre confocal imager with variable near-confocal control
WO1999035527A1 (en) * 1998-01-12 1999-07-15 Wallac Oy Confocal microscope with plural scanning beams
EP1627248A2 (en) * 2003-05-29 2006-02-22 The Regents of the University of Michigan Double-clad fiber scanning microscope
EP1627248A4 (en) * 2003-05-29 2008-06-04 Univ Michigan Double-clad fiber scanning microscope
WO2006076772A1 (en) * 2005-01-21 2006-07-27 Optiscan Pty Ltd Fibre bundle confocal endomicroscope
US8057083B2 (en) 2005-01-21 2011-11-15 Optiscan Pty, Ltd. Fibre bundle confocal endomicroscope

Also Published As

Publication number Publication date
US5659642A (en) 1997-08-19

Similar Documents

Publication Publication Date Title
US5659642A (en) Confocal microscope and endoscope
EP1245987B1 (en) Scanning confocal microscope
EP0523159B1 (en) Confocal microscope
US6172789B1 (en) Light scanning device and confocal optical device using the same
US6292287B1 (en) Scanning confocal optical device
US5926592A (en) Optical fibre confocal imager with variable near-confocal control
WO2002003118A2 (en) Fiber-coupled multiplexed confocal microscope
US6967772B2 (en) Scanning microscope with miniature head
JP2003517638A (en) Method and apparatus for imaging using optical waveguide bundle and spatial light modulator
EP0423112B1 (en) Achromatic scanning system
AU669760B2 (en) Confocal microscope and endoscope
WO1999004301A1 (en) Scanning microscope with miniature head
JP2001147383A (en) Scanning optical type optical device and endoscope using the same
US20030076587A1 (en) Confocal theta microscope
US6674057B1 (en) Optical near-field microscope
JP2001147398A (en) Scanning optical type optical device and endoscope using the same
WO1994018592A1 (en) Confocal microscope
AU643787B2 (en) Confocal microscope
AU652713B2 (en) Scanning confocal microscope
AU672876B2 (en) Confocal microscope
JPH03223709A (en) Confocal scanning type microscope
AU694005B2 (en) Optical fibre confocal imager with variable near-confocal control
JPH0324512A (en) Electronic endoscope device
CA1329255C (en) Confocal imaging system
IE20000001A1 (en) Optical imaging systems

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU CA JP KR NZ US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

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
WWE Wipo information: entry into national phase

Ref document number: 08424320

Country of ref document: US

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA