Life Science Solutions

Glossary of Terms in Near-Field Scanning Optical Microscopy

Section Overview:

Near-field scanning optical microscopy provides a technique for examining specimens with ultra-high spatial optical resolution that greatly expands the analytical toolbox of the microscopist. Listed in this section are links to resources on the web for near-field scanning optical microscopy, including university and government laboratories, technical tutorials, and microscope manufacturers.

Web Articles

  • Beckman Institute for Materials Science and Technology - A wide variety of excellent images created with a near field scanning optical microscope are included on the Beckman Institute site. Glenn Fried, of the Microscopy Suite, provides relatively simple schematics of the institute's near-field instrument and the principles behind the technique in a power point download.
  • Groeber Lab of Optical Imaging Spectroscopy - Yale University researchers at the Groeber Lab in the Department of Applied Physics and Physics emphasize the combined use of optical spectroscopy and optical imaging as a tool for materials characterization. The New Haven, Connecticut group, headed by Robert Groeber, posts published papers on the application of quartz tuning forks for NSOM feedback.
  • Haydon's Research Group - Phil Haydon applies NSOM to biological samples in order to discover new insights into the regulation of ion channels and synaptic transmissions in neurons. Haydon's research group, in the Department of Molecular Biology at Iowa State University, features NSOM and topographical images of a polytene chromosome on the site. A scanning electron micrograph of a metal-coated probe and an optical micrograph of a fiber probe emitting light are also provided.
  • Laboratory for Spectroscopic Imaging - The University of Texas research group, which is headed up by Paul Barbara, uses NSOM to image molecular semiconductor heterostructures and organic thin films. Ultrafast spectroscopy is also a focus of the Austin lab, which is equipped with NSOM, AFM, STM, and a laser scanning confocal microscope. The facility also explores the photophysical behavior of individual chromophore molecules to aid in the understanding of photoactivated processes in multi-chromophoric polymer films.
  • National Institute of Standards and Technology, Optical Technology Division - The Physics group at the NIST is extending measurements and standards to the nanoscale for the optical characterization of thin films and interfaces. High-resolution images of the wet-cell and metrological NSOM instruments are presented in the Gaithersburg, Maryland site. Examples of different techniques in NSOM are illustrated by digital images of a phase-separated polymer blend.
  • National Renewable Energy Laboratory - NSOM - The NSOM instrument at the NREL in Golden, Colorado was designed for solid state spectroscopy and operates at either room temperature or in a cryostat. The instrumental setup, and a SEM micrograph of an optical fiber probe tip, are featured. Low-temperature, spatially resolved photoluminescence of a GaInP epilayer, important in the semiconductor industry, is linked as an MPEG spectral video.
  • Superfine Group - The nanoscience research group, headed by Richard Superfine, at the University of North Carolina in Chapel Hill, conducts near-field research using polystyrene and magnetic particles as probes, rather than the traditional fiber optical probes. The mechanical properties of nanostructures in three dimensions, and their exploration with near-field and far-field optics are featured. A comprehensive NSOM educational page compares traditional optical microscopy to near-field optics. Informative text and diagrams help explain instrumentation, applications, and the optical principles behind them.
  • Ultra at Boston University - The Ultra research group, which is located in the Department of Physics, is involved in several near-field optical projects. Described on the site are a low-temperature, six-inch NSOM that reaches 4 degrees Kelvin and a custom built NSOM that was designed for studying laser diodes. With the integration of a metallurgical microscope, the custom NSOM enables the study of photoluminescence. A waveguide NSOM was especially designed for studying optically pumped devices, particularly waveguides. The site includes other high-tech optical instruments, a description of research projects, and a publications list.

Commercial Vendors

  • Cavendish Instruments - Cavendish Instruments is a leading supplier of software and instrumentation for measurement, monitoring, analysis, processing, simulation and modeling of information for a wide range of scientific and technological application areas. The company is dedicated to delivering value to its customers by providing innovative, powerful and flexible solutions with attention to customer support and service.
  • Danish Micro Engineering A/S - Founded by Curt Sander, Danish Micro Engineering A/S developed a scanning probe microscope in 1987. Acting as an industry leader and innovator, the company carries a complete line of hardware for integrated scanning probe microscopes including atomic force microscopes, scanning near-field optical microscopes, and scanning tunneling microscopes. Scanned application images, placed in the broad categories of biology, data storage, metallurgy, optical characterization, polymer, and semiconductors, are provided on the site.
  • JASCO Chromatograph and Spectroscopy Products - JASCO markets a near-field scanning optical micro photoluminescence and Raman spectrometer that enables the observation of photoluminescence and fluorescence spectra at sub-wavelength, high-spatial resolutions. Single semiconductor quantum dots and wires can be spectrally resolved at less than 100 nanometers. JASCO also provides a well-written introduction to near-field scanning optical spectroscopy that compares far-field and near-field techniques, and includes discussions on STM, NSOM, and AFM.
  • Nanonics Imaging Ltd - Beyond basic research, Nanonics manufactures a unique NSOM/AFM system that operates on either an inverted or an upright optical microscope stand. The NSOM head performs Raman spectroscopy when combined with a Renishaw Raman microscope. Rather than depending on outside sources, Nanonics produces tip pipettes in their class-100 clean room in Jerusalem, Israel. Overviews of NSOM are well illustrated and provide an excellent introduction to the technique.
  • NT-MDT - Molecular Devices and Tools for NanoTechnology, based in Moscow, Russia, supplies the world market with high quality scanning probe microscopes and related accessories. NT-MDT also manufactures straight coated optical fiber NSOM probes. The NT-MDT Solver NSOM features a shear-force feedback system combined with AFM and STM capabilities.
  • Omicron Instruments for Surface Science - Recently renamed Omicron NanoTechnology, the German manufacturer produces the TwinSNOM (scanning near-field optical microscope) in a shear-force configuration that allows either reflection or transmission mode imaging as well as optical microscopy. More than a dozen examples of applications are provided as are a summary of basic NSOM principles and a bibliography.
  • Triple-O Microscopy - The German company manufactures the BioLyser SNOM, which features the triple functions of near-field, AFM, and inverted optical microscopes, and that allows fluorescence, polarization, and spectroscopic studies at 100-nanometer resolution. Most types of NSOM tips, including straight, bent fibers, and cantilevers, are accommodated by the near-field system. Windows-compatible software accompanies the BioLyser. Background information on scanning probe microscopy and an image gallery that contrasts the modes of operation round out this very informative website.
  • Veeco Instruments - Veeco manufactures second and third generation near-field microscopes under their Aurora product name in a shear-force configuration, as well as other scanning probe instruments and electronics. In 2001, Veeco purchased Thermomicroscopes, the maker of TM Microscopes and the successor to the merger of Topometrix and Park Scientific. Topometrix produced the first commercial NSOM instrument and their name is found in many NSOM research papers.
  • WITec Wissenschaftliche Inst und Tech GmbH - German-based WITec designed the AlphaSNOM for use in the material and life sciences. The optical instrument combines confocal, atomic force, and scanning near-field optical microscopy. Cantilevered near-field sensors facilitate imaging in fluids and reportedly outperform the resolution, transmission, user friendliness, and reliability of standard fiber optical probes. Modularity increases the flexibility and versatility of the high precision optical instrument for a large variety of applications. Ten downloadable applications of NSOM are featured on the WITec website.