Field microscopy

At this point it is worth comparing the different techniques of contrast enliancements discussed so far. They represent spatial filtering teclmiques which mostly affect the zeroth order dark field microscopy, which eliminates the zeroth order, the Schlieren method (not discussed here), which suppresses the zerotii order and one side band and, finally, phase contrast microscopy, where the phase of the zeroth order is shifted by nil and its intensity is attenuated. 

Bian R X, Dunn R C, Xie X S and Leung P T 1995 Single molecule emission characteristics in near-field microscopy Phys. Rev. Lett. 75 4772-5... 

There are three primary image modes that are used in conventional TEM work, bright-field microscopy, dark-field microscopy, and high-resolution electron microscopy. In practice, the three image modes differ in the way in which an objective diaphragm is used as a filter in the back focal plane. 

In bright-field microscopy, a small objective aperture is used to block all diffracted beams and to pass only the transmitted (undiffracted) electron beam. In the... 

A nano-light-source generated on the metallic nano-tip induces a variety of optical phenomena in a nano-volume. Hence, nano-analysis, nano-identification and nanoimaging are achieved by combining the near-field technique with many kinds of spectroscopy. The use of a metallic nano-tip applied to nanoscale spectroscopy, for example, Raman spectroscopy [9], two-photon fluorescence spectroscopy [13] and infrared absorption spectroscopy [14], was reported in 1999. We have incorporated Raman spectroscopy with tip-enhanced near-field microscopy for the direct observation of molecules. In this section, we will give a brief introduction to Raman spectroscopy and demonstrate our experimental nano-Raman spectroscopy and imaging results. Furthermore, we will describe the improvement of spatial resolution... 

Kottmann, J. P., Martin, O. J. F Smith, D. R. and Schultz, S. (2001) Non-regularly shaped plasmon resonant nanopartide as localized light source for near-field microscopy. J. Microsc., 202, 60-65. 

The contribution of near-field microscopy is not limited to studies on plasmon-based nanomaterials, but may also provide valuable fundamental information on novel functions of various nanomaterials. 

Courjon, D. (2003) Near-Field Microscopy and Near-Field Optics, Imperial College Press, London. 

Imaging of surface plasmon and ultrafast dynamics in gold nanorods by near-field microscopy. J. Phys. Chem. B, 108, 16344-16347. 

In wide field microscopy, spatial information of the entire image is acquired simultaneously thus providing comparatively short acquisition times compared with scanning microscopy implementations. Combining TCSPC with wide field microscopy is not straightforward. However, a four quadrant anode multichannel plate (MCP) has been used for time- and space-correlated SPC experiments [25, 26]. This detector has excellent timing properties that make it very suitable for FLIM. Unfortunately, it can be operated only at low count-rates ( 105-106 Hz) therefore, it requires comparatively long acquisition times (minutes). 

Note that parameters ft and 5 depend on signal amplifications in the utilized detectors and on the elements in the optical path (optical filter, spectral detection bands) only, while a and y are additionally influenced by relative excitation intensity. This is usually a fixed constant in wide-field microscopy but in confocal imaging laser line intensities are adjusted independently. Furthermore, note that the a factor equals 5 multiplied by y (see Appendix for further detail). 

Dark-Field Microscopy and Its Application to Pollen Tube Culture... 

Dark-Field Microscopy Application of Dark-Field Microscopy to Pollen Tube Culture The Protocol... 

Instrument Setup for Simple Dark-Field Microscopy... 

As described before, special built-in equipment is not always necessary for dark-field microscopy, and one can readily convert bright-field illumination to dark-field illumination. An inverted microscope equipped with long-distance (low NA) lenses is suitable for setup of a dark-fieldmicroscope. A handmade ring-slit is available when objective lenses such as x4 lens withNA 0.13, xlO lens withNA 0.30, and x20 lens... 

APPLICATION OF DARK-FIELD MICROSCOPY TO POLLEN TUBE CULTURE... 

Matsunaga S, Kawano S, Higashiyama T, InadaN, Kuroiwa T. Clear visualization of the products of nonradioactive in situ hybridization in plant tissue by simple dark-field microscopy. Micron 1997 28 185-187. 

Atomic force microscopy (AFM) is a variant of STM and was introduced in 1986 by Binnig et al. (11). AFM belongs to a family of near-field microscopies and is capable of imaging a wide variety of specimens surface down to an atomic scale. The technique employs a probe (pyramidal tip) mounted at the end of a sensitive but rigid cantilever (see Fig. 2). The probe is drawn across the specimen under very light mechanical loading (1). Measurements of the probe s interaction with the sample s surface are accomplished with a laser beam reflected from the cantilever. 

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