Phase Contrast Imaging Thesis Example | Topics and Well Written Essays - 3750 words

Phase Contrast Imaging - Thesis Example The traditional approach is reliant on X-ray absorption as a mere source of contrast, and also outlines chiefly on ray optics to define and interpret the formation of image. As suggested by Yacobi et al, Phase contrast is the most challenging and complicated mechanism for a beginner to imagine, however, at the same time, it is the most powerful mechanism for generating images with ultra-high resolution (Yacobi et al, 1994). Phase Contrast imaging, which is informally known as High Resolution or HR imaging, is a process of imaging in Transmission Electron Microscopy, and is one of the chief components that discriminates Transmission Electron Microscopy from traditional optical microscopy. Nevertheless, phase contrast imaging is often interpreted as synonymous to high-resolution TEM (Williams and Carter, 1996). Moreover, phase contrast microscopy produces high-contrast images of transparent samples such as cells or micro-organisms (Murphy, 2002). This ability commences from the fact that the atoms in a substance disseminate electrons as they pass through them, thereby, giving rise to diffraction in contrast, along with the distinction that is already prese nt in the transmitted beam. Phase-contrast imaging contributes to the maximum imaging technology that has ever developed, and can also enable for resolutions ranging less than one angstrom, thus, allowing the straight viewing of lines of atoms in a crystalline substance. As suggested by Wilkinson and Schut, in phase contrast microscopy, the differences in refractive index are converted into differences in the image intensity (Wilkinson and Schut, 1998). The explanation of phase-contrast images is usually not a clear-cut task by any means. As viewed by Zhang, phase contrast images usually exhibit periodic contrast transformations or reversals (Zhang, 2001). The uncoiling of the differences viewed in the High Resolution image in order to identify the features as a result of which the atoms in the substance can hardly be performed with the naked eye. As an alternative, for the reason that the merger of contrasts as a reason of the multiple diffracting constituents as well as planes and the transmitted beam is diverse, the computer replications are brought in to use so as to identify what kind of distinct disparate structures may create in a phase-contrast image. As a point in fact, a sensible amount of information regarding the sample is required to be comprehended prior to the interpretation of a phase contrast image, for example a speculation about the constituents of the