Dark-field microscopy

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. 

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. 

Tdrdk P, Sheppard C J R and LaczikZ 1996 Dark field and differential phase contrast imaging modes in confocal microscopy using a half aperture stop Optik 103 101-6... 

In dark-field electron microscopy it is not the transmitted beam which is used to construct an image but, rather, a beam diffracted from one facet of the object under investigation. One method for doing this is to shift the aperture of the microscope so that most of the beam is blocked and only those electrons... 

S. J. Pennycook. EMSA Bulletin. 19, 67, 1989. A summary of compositional imaging using a high-angle annular dark-field detector in a field emission STEM instrument published by the Electron Microscopy Society of America, Box EMSA Woods Hole, MA 02543. 

The structure of the metal particles dispersed on a silica powder support ( Aerosil 380, 70 A average silica particle diameter) has been studied by Avery and Sanders (47) using electron microscopy in both bright and dark field, to determine the extent to which the metal particles were multiply twinned or of ideal structure. Platinum, palladium, and gold were examined. These catalysts were prepared by impregnation using an aqueous solution of metal halide derivatives, were dried at 100°-150°C, and were hydrogen... 

Fig. 12. Schematic of the information from HRSTEM, DF, and high-angle annular dark-field (HAADF) microscopy.

Dark field Visualization technique for ashes produced by microincineration and fluorescence microscopy useful for low-contrast subjects Electron systems imaging EM shadowing Detection, localization, and quantitation of light elements Structural information from ordered arrays of macromolecules... 

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. 

Plant Cells and Tissues Structure-Function Relationships. Methods for the Cytochemical/Histochemical Localization of Plant Cell/Tissue Chemicals. Methods in Light Microscope Radioautography. Some Fluorescence Microscopical Methods for Use with Algal, Fungal, and Plant Cells. Fluorescence Microscopy of Aniline Blue Stained Pistils. A Short Introduction to Immunocytochemistry and a Protocol for Immunovi-sualization of Proteins with Alkaline Phosphatase. The Fixation of Chemical Forms on Nitrocellulose Membranes. Dark-Field Microscopy and Its Application to Pollen Tube Culture. Computer-Assisted Microphotometry. Isolation and Characterization of... 

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