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| July 31, 2010 at 2.53pm |
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Welcome to Nova Instruments. A Whirlwind of Innovation! We are certain that as you look through our product line you will find the quality and affordability that your customers are looking for. We carry a full range of compound, stereo, stereozoom, metallurgical, and inverted microscopes Along with many accessories from digital video systems, to light sources, to microscope cases. Nova Instruments is your one stop microscope source. |
 Become a Nova® distributor. Nova® Instruments is continually looking for quality microscope distributors. If you would like more information on becoming a Nova® distributor please follow this link. |
Random Vocabulary: phase-amplitude contrast: The separation and recombination of direct vs. diffracted rays in a light microscope adjusted to Kohler illumination (q.v.). At the lower focal plane of the condenser there is an annular diaphragm with an opaque central stop. Through this diaphragm rays are focused as a hollow one onto the specimen. In the back focal plane of the objective there is a conjugate annular diaphragm (phase plate). If here the undiffracted rays are retarded (by a transparent film of proper thickness on the annulus of the phase plate), bright contrast results. If, instead, the phase-delay film is on the central spot, dark contrast results. With either a bright or a dark-contrast phase plate, the annulus is usually coated with a partially absorbing (very thin) film of silver (Zemike method) or carbon soot (Wilska method) to reduce the higher amplitude (intensity) of the undiffracted rays. |
Nova® Instruments 6310 SW Virginia Avenue Portland, Oregon 97201 (503)246-8297 | (503)246-0360 FaxCopyright 2000 - Nova® Instruments - Page Created July 1998 - Last Updated April 13, 2001 |