Search Results for phase contrast illumination

This article provides information on the basic components of a light microscope, including the illumination system, collector lens, and optical and mechanical components. It describes optical performance in terms of image aberrations, resolution, and depth of field. The article discusses the examination of specimen surfaces using polarized light, phase contrast, oblique illumination, dark-field illumination, bright-field illumination, interference-contrast illumination, and phase contrast illumination. Special techniques and devices that may be used with the optical microscope, to obtain additional information, are also described. The article concludes with information on photomicroscopy and macrophotography.

The analysis of composite materials using optical microscopy is a process that can be made easy and efficient with only a few contrast methods and preparation techniques. This article is intended to provide information that will help an investigator select the appropriate microscopy technique for the specific analysis objectives with a given composite material. The article opens with a discussion of macrophotography and microscope alignment, and then goes on to describe various illumination techniques that are useful for specific analysis requirements. These techniques include bright-field illumination, dark-field illumination, polarized-light microscopy, interference and contrast microscopy, and fluorescence microscopy. The article also provides a discussion of sample preparation materials such as dyes, etchants, and stains for the analysis of composite materials using optical microscopy.

Zirconium, hafnium, and their alloys are reactive metals used in a variety of nuclear and chemical processing applications. This article describes various specimen preparation procedures for these materials, including sectioning, mounting, grinding, polishing, and etching. It reviews some examples of the microstructure and examination for zircaloy alloys, hafnium, zirconium, and bimetallic forms.

Quantitative image analysis has expanded the capabilities of surface analysis significantly with the use of computer technology. This article provides an overview of the quantitative image analysis and optical microscopy. It describes the various steps involved in surface preparation of samples prone to abrasion damage and artifacts for quantitative image analysis.

This article illustrates the polymer matrices used for composite materials. It describes the use of prepeg materials in manufacturing high-performance composites. The article discusses the various infusion processes for the development of fiber-reinforced composites, namely, resin transfer molding, vacuum-assisted resin transfer molding, and resin film infusion. It explains the composite- and matrix-toughening methods for fiber-reinforced composites, such as dispersed-phase toughening and interlayer toughening. The article concludes with information on optical microscopy, which provides an insight into the micro- and macrostructure of fiber-reinforced composites.

This article is a compilation of definitions of terms related to metallography and microstructures.

Microscopy is a valuable tool in materials investigations related to problem solving, failure analysis, advanced materials development, and quality control. This article describes the sample preparation techniques of composite materials. These techniques include mounting, rough grinding, and polishing. The preparation techniques of ultrathin sections are also summarized. The article explains the illumination methods used by reflected light microscopy to view a specimen. These consist of epi-bright-field illumination, epi-dark-field illumination, epi-polarized light, and epi-fluorescence. The article also provides information on transmitted light microscopy.

The reflected light microscope is the most commonly used tool to study the microstructure of metals, composites, ceramics, minerals, and polymers. For the study of the microstructure of metals and alloys, light microscopy is employed in the reflected-light mode using either bright-field illumination, dark-field illumination, polarized light illumination, or differential interference contract, generally by the Nomarski technique. This article concentrates on how to reveal microstructure properly to enable the proper identification of the phases and constituents and, if needed, measuring the amount, size, and spacing of constituents, using the light optical microscope. The discussion covers the examination of microstructures using different illumination methods and includes a comparison between light optical images and scanning electron microscopy images of microstructure.