Transmitted light optical microscopy

We use optical microscopy to examine samples at magnifications from about 5x up to approximately l,000x. Samples may be examined using either transmitted or reflected light, depending on the nature of the sample and the information that we are seeking. 

Optical microscopy is another method that has been used to determine the distribution of minerals in coal. This method is based on the detailed microscopic examination of polished or thin sections of coal in transmitted and/or reflected light. In principle, observing several of its optical properties, such as morphology, reflectance, refractive index, and anisotropy, makes identification of a mineral type possible. 

Optical microscopy of resin and plastisols were conducted using transmitted light on a Zeiss Optical Microscope. 

Optical Microscopy. Optical microscopy involves the use of transmitted light, reflected light, polarized light, fluorescence, and more recently, techniques such as confocal microscopy. Each of these variations has particular strengths and applicability. 

Studies by optical microscopy of the material left after evaporating the benzene show a variety of what appear to be crystals—mainly rods, platelets and star-like flakes. Figure 1 shows a micrograph of such an assemblage. All crystals tend to exhibit six-fold symmetry. In transmitted light they appear red to brown in colour in reflected light the larger crystals have a metallic appearance whereas the platelets show interference colours. The platelets can be rather thin and are thus ideally suited for electron-diffraction studies in an electron microscope (see the inset in Fig. 3). 

Fluorescence microscopy can be performed by either transmitted or reflected illumination (epi-illumination). Reflected light is more commonly used because it entails less loss of excited fluorescence than transmitted light. Figure 1.43 illustrates the optical arrangement for... 

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