Bright field optical microscope

Figure 4.3. Bright field optical microscope images for epoxy composites containing 0.05 wt% SWNT (a), 0.05 wt% SWNT, and 2 wt% clay (c), images (b) and (d) are the same respective positions, but under cross-polarized light condition. Reprinted with permission from ref (41).

Figure 5. Uncracked and cracked Knoop indentations in the BK 7 borosilicate crown glass at 19.6 N. Indentations should be spaced further apart for most testing purposes in order to avoid interference, (a) is a bright field and (b) dark field optical microscope illumination. The dark field photo reveals that some localized cracking occurs under the left indentations, but the extent of cracking is dramatically different. The cracked indentation is 7 pjn longer.

Note If chromosome bands appear too weak in a microscope with bright-field optics, repeat staining. 

TIRF is easy to set up on a conventional upright or inverted microscope with a laser light source or, in a special configuration, with a conventional arc source. TIRF is completely compatible with standard epi-fluorescence, bright-field, dark-field, or phase contrast illumination so that these methods of illumination can be switched back and forth readily. Some practical optical arrangements for observing TIRF through a microscope are described in Section 7.4. 

Bright-Field Illumination A kind of illumination for microscopy in which the illumination of a specimen is arranged so that transmitted light remains in the optical path of the microscope and is used to form the magnified image. This is different from the arrangement in Dark-Field Illumination. 

Then, microscopic examinations follow optical research microscopes allow to determine the number, thickness, and color sequence of layers in paint fragments, and to recognize the textures as well as fundamental features of pigment and extender mixtures. Bright field and dark field illuminations, polarized light microscopy (incident and transmitted), particularly the differential interference contrast (DIC) procedure, and fluorescence microscopy are necessary for paint examinations (see Figure 3(A)-3(E)). 

The conventional transmitted-light compound microscope uses a bright-field system, in which the condenser gives a bright, even illumination across the whole of the field of view. This form of illumination, when correctly set up, is ideal for the examination of a wide range of specimens, particularly stained thin sections of biological material. Where there are no natural variations in color or optical density of the... 

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