Colour display of video information in scanning electron microscopy: Principles and applications to physics, geology, soil science, biology, and medicine

Abstract

From a colourimetric point of view, colour has two independent aspects: brightness and chromaticity. In black and white images, all elements are of the same chromaticity and can be distinguished only by brightness contrast. In the colour image, elements of the same brightness can be discriminated by chromaticity (colour) contrast. Generally, colour image elements can be discriminated both by brightness and by chromaticity. As the human eye can distinguish a number of hues two orders of magnitude larger than the number of grey levels, it is safe to say that the colour image is much more informative than the black and white image. There are some peculiarities of the colour image and methods of its formation in SEM. Two principles of image formation are used. The first consists of the formation of a real colour image in the cathodoluminescence mode. In this case the colour of an image element is determined by the spectrum of the luminescence emission excited in the corresponding point of an object by the electron beam. The second principle is that of colour coding (quasicolour, pseudocolour), when a video signal in colour (either digital or analog) corresponds to a video signal (amplitude, frequency, phase, etc.) produced by any mode in the scanning electron microscope. We present a review of the methods of colour display of video information in scanning electron microscopy and their applications to physics, geology, soil science, biology, and medicine.

A simple method for the acquisition of high‐quality digital images from analog scanning electron microscopes

“…High object contrasts can be reduced by local corrections of brightness and gradation curve ( Oho, 1992), a method exceptionally useful for backscattered electron images ( Oho et al ., 1991 ). Images obtained from different detectors, such as secondary electron and backscattered electron detectors, can easily be combined in a colour‐encoded image and thereby it is possible to visualize information of both sources in a single image ( Swift & Brown, 1975; Saparin & Obyden, 1987; Postek & Vladár, 1996).…”

New growth features of natural diamonds, revealed by color cathodoluminescence scanning electron microscope (CCL SEM) technique

“…The study of the internal structure of diamonds by color cathodoluminescence (CCL) in a scanning electron microscope has special advantages. It is known that the microzonality typical for the majority of diamonds is caused by The peculiarities of the internal structure of diamonds were studied by means of polarization optical techniques and CCL-SEM was described by Saparin and Obyden (1988).…”

Color cathodoluminescence of BGO crystals

“…The experiments were carried out in the "Stereoscan" SEM using standard attachment for color CL described by Saparin and Obyden (1988). The basic difference when using this method is the receiving system, which is made up of three photomultipliers with different light filters (R, G, B) and a multichannel device connected to the photomultipliers.…”