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Biographical sketch: Professor  E. McCabe, M.A.(Oxon), D.Phil.(Oxon), B.E.(NUI), F.Inst.P., C.Phys.

Current:

Fellow, Trinity College Dublin.
Fellow, Institute of Physics.

Previous:

Lecturer, Magdalen College Oxford, 1991-1992.
Research Fellow of the Royal Commission for the Exhibition of 1851, University of Oxford, 1991-1992.
Fellow of Magdalen College Oxford, 1987-1991.
Member of Governing Body, Magdalen College Oxford, 1987-1991.
Postdoctoral Member of Technical Staff, AT&T Bell Laboratories, New Jersey, USA. All of 1988.
Consultant, AT&T Bell Laboratories, Summer 1989.
Zonta Amelia Earhart International Fellowship Award, 1988.
Senior Scholar, Lincoln College Oxford, 1986-1987.
Royal Television Society Baird Travelling Scholarship, 1986.
The Hewlett Packard award for Innovation in Electrical Engineering, 1984.
Institute of Chemistry Gold Medal for First Place in Leaving Certificate Chemistry, 1980.

Administrative experience - outline:

International Union of Pure and Applied Physics team leader for Women in Physics initiative, 2001/2002
Member of organising committee/Chair for the SPIE (The International society for Optical Engineering)Photonics West conference, San Jose, USA, 1999-2003
Secretary and member of the Institute of Physics Education sub-group, 1996-2001
Institute of Physics Tyndall lecture series coordinator.
Enterprise Ireland research grant committees, 1998-
Member of Finance Committee, TCD, 2001-
Member of Working Party on Teaching and Learning, TCD, 2001-
Member of Staff Appointments Committee, TCD, 2000-
Member of Catering Management Committee, TCD, 2001-
Member of Graduate Studies Committee, TCD, 1993-1996
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 (a)                                                                                            (b)

 (c)                                                                                             (d)
 

Confocal photoluminescence images of a II-VI laser structure showing the progressive stages of degradation and annealing in a ZnCdSe/ZnSSe/ZnMgSSe separate confinement heterostructure: (a) t=0, (b) t=15 sec., (c) t=2 min., (d) t= 40 min.

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Other group members: Dr. L.Yang, Dr.A.Dunbar, Mr.S.Walker, Mr.A.MacRaighne, Ms.J.Garry
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Background

 Optical microscopy has seen many rapid changes over the last twenty years. The field of confocal microscopy has revolutionised the way biologists, physicists and engineers alike use light to image a whole range of samples from biological cells to semiconductor devices. The three-dimensional, high-resolution, non-destructive features of confocal microscopy are captivating new microscope users and driving the development of radically new types of confocal microscopes. The confocal group at Trinity focuses in considerable detail on the theoretical as well as the experimental aspects of confocal imaging.

Confocal imaging in a confocal microscope is usualy achieved by placing a small pinhole in front of the photodetector in a scanned imaging system. This results in two key features of confocal imaging:

(1) Increased lateral resolution (typically 0.5 micron using a red light source, and even better resolution using shorter wavelength sources)

(2) An optical sectioning capability: Essentially only the part of the specimen in the focal plane of the objective lens is imaged. Light collected from outside the focal plane of the lens is rejected by the pinhole. In this way a slice of an object may be imaged. Scanning permits very many slices to be imaged. In this way high resolution, three-dimensional images may be built up of a variety of specimens in a non-destructive fashion.
 
 

  These images may be brightfield, or reflection, giving surface topography, for example or they may show sub-surface features. The images above show how confocal photoluminescence imaging may be used to image features in the active region of a II-VI laser structure. This research was carried out in collaboration with Sony in Japan and Dr. John Donegan in Trinity who is an expert in wide-bandgap materials. In this case the defects imaged change with time and conditions. These changes may be explained in terms of both device degradation and annealing.
 

A direct-view microscope is a significant modification of a confocal microscope in that it uses multiple-aperture arrays in the source and detector planes. By scanning these apertures, real-time images may be built up. In practice this aperture array consists of a disk with many pinholes. By scanning this disk, quasi-confocal images may be obtained at speed.
 


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Direct-view microscope setup ______________________________________________________________________________________________________________________________________________________________________________

One of the current research interests of the confocal research group at Trinity is the issue of developing a theory which optimises this pinhole congiguration in terms of shape and aperture spacing in direct-view microscopy. A state-of-the-art confocal microscope in our laboratory acts as a test-bed for experimental work to test our theory.

 The Trinity confocal group is currently investigating the adaptation of current microscopes to improve imaging properties of three-dimensional confocal microscopes. There is also significant emphasis on the design of entirely new kinds of microscopes. The group is involved in the whole applications side of confocal microscopy, both from a physics and engineering perspective, and would welcome further industrial and academic interaction. There is already strong interaction with Optronics which is an Irish government sponsored initiative whose aim is to bring suitable optoelectronic research ideas to prototype stage and beyond.

For further information contact:

Prof. Eithne McCabe
Department of Physics
Trinity College Dublin
Dublin 2
Ireland.

Eithne.McCabe@tcd.ie

Some recent publications________________________________________________________________________________________________________________________________________________________________
 
Effects of source coherence and aperture array geometry on optical sectioning strength in direct-view microscopy,
J.Opt.Soc.Am.A, 19,7,1406-1416, (2002)
C.M.Taylor and E.M.McCabe

Novel Imaging in Confocal Microscopy,
In Press, Proceedings of SPIE, (2002)
E.M.McCabe, C.M.Taylor and L.Yang

Source coherence and optical sectioning in DVMs,
Proceedings of the SPIE conference on Progress in Biomedical Optics and Imaging, 4621, 32-39, (2002)

Switchable fibre coupling using variable-focal-length microlenses,
Review of Scientific Instrumentation, 72, 7, (2001)
C.M.Taylor, P.J.Smith, E.M.McCabe, D.R.Selviah, S.E.Day and L.G.Commander

Programmable array microscope employing two ferroelectric liquid crystal spatial light modulators,
Proceedings of the SPIE conference on Progress in Biomedical Optics and Imaging,  4261, 33-39, (2001)

Programmable array microscopy using a ferroelectric liquid crystal SLM,
Applied Optics, 39, 16, 2664-2669 (2000),
P.J.Smith, C.M.Taylor, A.J.Shaw and E.M.McCabe

Optical Imaging Systems,
Irish Patent N0. 81647, (2000)
E.McCabe

Variable-focus Microlenses as a potential technology for Endoscopy,
Proceedings of the SPIE conference on Progress in Biomedical Optics, Three-dimensional and Multidimensional Microscopy: Image Acquisition and Processing VI, San Jose, California, USA, 3919, 187-192, (2000),
P.J.Smith, E.M.McCabe, C.Taylor, D.R.Selviah, S.E.Day and L.G.Commander

A programmable array microscope demonstrator: application of a ferroelectric liquid crystal SLM,
Proceedings of the SPIE conference on Progress in Biomedical Optics, Three-dimensional and Multidimensional Microscopy: Image Acquisition and Processing VI, San Jose, California, USA, 3919, 21-29, (2000),
C.Taylor, P.J.Smith and E.M.McCabe

Recoveryof degradation in II-VI laser diode structure,
Electronics Letters, 35, 15, 1281-1282,(1999)
C.Jordan, E.M.McCabe, J.F.Donegan, K.Nakano, A.Ishibashi and S.Itoh

Optical imaging systems,
Irish Patent No. S990004. Filed January 4, (1999),
E.McCabe

Confocal photoluminescence microscopy in II-VI materials: annealing and degradation dynamics,Proceedings of the SPIE conference on Progress in Biomedical Optics, Three-dimensional and multidimensional Microscopy: Image Acquisition and Processing VI, 3605, 65-72, (1999),E.M.McCabe, C.Jordan, D.T.Fewer, J.F.Donegan, S.Taniguchi, T.Hino, K.Nakano, A.Ishibashi, P.Uusimaa, M.Pessa

Optical sectioning using finite-sized, multiple aperture arrays in fluorescence Direct-View Microscopy; Experimental Results,
Proceedings of the SPIE conference on Progress in Biomedical Optics, , Three-dimensional and multidimensional Microscopy: Image Acquisition and Processing VI, 3605, 236-240, (1999), P.J.Smith, C.Taylor and E.M.McCabe

Laser sources in direct-view, tandem- or Nipkow disc-scanning confocal microscopy,
J.Applied Optics, 37, 2, 380-385, (1998),
D.T.Fewer, S.J.Hewlett and E.M.McCabe

Defect annealing in a II-VI laser diode structure under intense optical excitation,
Applied Physics Letters, 72, 2, 194-196, (1998),
C.Jordan, D.T.Fewer, J.F.Donegan, E.M.McCabe, A.Huynh, F.P.Logue, S.Taniguchi, T.Hino, K.Nakano and A.Ishibashi

Imaging in fluorescence direct-view microscopy,
J. Opt. Communications,152, 393-402, (1998),
D.T.Fewer, S.J.Hewlett and E.M.McCabe

Defect annealing in a II-VI laser diode structure under intense optical excitation,
J.Crystal Growth,184/185, 585-586, (1998),
C.Jordan, D.T.Fewer, J.F.Donegan, F.P.Logue, E.M.McCabe, A.Huynh, S.Taniguchi, T.Hino, K.Nakano and A.Ishibashi

Optical and Electrical Properties of a Polymer-Nanotube Composite,
Excitonic Processes in Condensed Matter,Editors R.T.Williams and W.M.Yen, New Jersey, The Electrochemical Society, (1998), 147-153,
J.N.Coleman, A.B.Dalton, S.Curran, A.P.Davey, B.McCarthy, A.Drury, E.McCabe, S.Roth and W.Blau 

Influence of source coherence and aperture distribution on the imaging properties in direct-view microscopy,
J.Optical Society of America A, 14, 5, 1066-1075, (1997),
S.J.Hewlett, D.T.Fewer and E.M.McCabe

Direct-view microscopy: experimental investigation of the optical sectioning characteristics on pinhole-array configuration,
J.Microscopy, 187, 1, 54-61, (1997),
D.T.Fewer, S.J.Hewlett , E.M.McCabe and J.Hegarty

Optical measurement of the ambipolar diffusion length in a ZnCdSe-ZnSe single quantum well,
J. Applied Physics, 81, 536-538, (1997),
F.P.Logue, D.T.Fewer, S.J.Hewlett, J.F.Heffernan, C.Jordan, P.Rees, J.F.Donegan, E.M.McCabe, J.Hegarty, S.Taniguchi, T.Hino, F.Hieiand A. Ishibashi

Semiconductor optical device and method for producing same,
Japanese Patent H9-103153, Filed 21 April, (1997),
J.F.Donegan, C.Jordan, D.T.Fewer,E.M.McCabe, A.Ishibashi, A.Toda, M.Shiraishi, Y.Sanaka, and N.Noguchi

Degradation dynamics of II-VI (ZnCdSe) quantum well materials using confocal photoluminescence microscopy,
Proceedings of Royal Microscopical Society Conference on Microscopy of Semiconducting Materials. Institute of Physics Conf. Ser.157,569-572, (1997),
D.T.Fewer,C.Jordan, S.J.Hewlett, E.M.McCabe, F.P.Logue, J.F.Donegan,J.Hegarty, S.Taniguchi, T.Hino, K.Nakano and A.Ishibashi

Comparison of experiment and theory for finite-sized, multiple-aperture arrays in direct-view microscopy,
Proceedings of the SPIE International Conference on Biomedical Optics; Three Dimensional Microscopy: Image Acquisition and Processing IV,2984, 90-100, (1997) (ISBN 0-8194-2395-5) D.T.Fewer, S.J.Hewlett and E.M.McCabe
 

Direct-view Microscopy: Optical sectioning strength for finite-sized, multiple-pinhole arrays,
J.Microscopy, 184, 95-105 (1996),
E.M.McCabe, D.T.Fewer,A.C.Ottewill, S.J.Hewlett and J.Hegarty

Theory of finite-sized, multiple-aperture arrays in direct-view microscopy.
Proceedings of the SPIE International Conference on Electronic Imaging: Three-Dimensional Microscopy: Image Acquisition and Processing III, 2655, 99-108, San Jose, California, USA, 1996, ISBN 0-8194-2029-8,
E.M McCabe, A C Ottewill, D T Fewer, S J Hewlett, J Hegarty, T Wilson.

Gain and carrier dynamics at lasing densities in ZnCdSe quantum well materials.
23rd International Conference on the Physics of Semiconductors, 3183-3186, Berlin, Germany, 1996.
J F Donegan, F P Logue, C Jordan, P Rees, S J Hewlett, J F Heffernan, D T Fewer, E M McCabe, J Hegarty, S Taniguchi, T Hino, K Nakano, A Ishibashi.
 
 

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Last updated 15 October 2002 by Eithne.McCabe@tcd.ie.