High-resolution scanning surface-plasmon microscopy.

Surface plasmons (SP's) are electromagnetic surface waves that propagate along the interface between conductors and dielectrics. The k vector of these waves is larger than the free-space wave vector. The importance of SP's lies in the fact that they are extremely sensitive to small changes in the dielectric properties of substances that are in contact with the conductors. This property means that SP's have many sensor applications; however, when they are used in microscopic applications the lateral resolution is limited to several micrometers. We discuss how this limit can be overcome by use of defocused high-numerical-aperture liquid-immersion objectives. We also present SP images that demonstrate a resolution comparable with that expected from high-numerical-aperture optical microscopes. Finally, we discuss how ultrahigh-numerical-aperture objectives with numerical apertures greater than 1.5 can be expected to have considerable influence on biological imaging.

[1]  Use of heterodyne detection to measure optical transmittance over a wide range. , 1990, Applied optics.

[2]  Novotny,et al.  Local Excitation, Scattering, and Interference of Surface Plasmons. , 1996, Physical review letters.

[3]  S. Hell,et al.  4Pi‐confocal images with axial superresolution , 1996 .

[4]  Jan Greve,et al.  RESOLUTION IN SURFACE PLASMON MICROSCOPY , 1994 .

[5]  Henry L. Bertoni,et al.  Ray interpretation of the material signature in the acoustic microscope , 1979 .

[6]  M. Somekh,et al.  Optical V(z) for high-resolution 2pi surface plasmon microscopy. , 2000, Optics letters.

[7]  Colin J. R. Sheppard,et al.  Aberration measurement in confocal microscopy: Phase retrieval from a single intensity measurement , 1997 .

[8]  Michael G. Somekh,et al.  Acoustic microscopy of elastic discontinuities , 1984, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[9]  Wolfgang Knoll,et al.  Surface–plasmon microscopy , 1988, Nature.

[10]  C Bechinger,et al.  Imaging of cell/substrate contacts of living cells with surface plasmon resonance microscopy. , 1999, Biophysical journal.

[11]  R. J. Green,et al.  Adsorption of PEO-PPO-PEO triblock copolymers at the solid/liquid interface : A surface plasmon resonance study , 1997 .

[12]  R. H. Pantell,et al.  Surface plasmon resonance and immunosensors , 1984 .

[13]  Abdullah Atalar,et al.  Phase imaging in reflection with the acoustic microscope , 1977 .

[14]  M. Somekh,et al.  Direct far-field observation of surface-plasmon propagation by photoinduced scattering , 1999 .

[15]  Eric M. Yeatman,et al.  Resolution and sensitivity in surface plasmon microscopy and sensing , 1996 .