O’zbekistоn respublikasi оliy va o’rta maxsus ta`lim vazirligi

The method of light and shadow glow is the most commonly used methods for measuring the parameters of irregularities. The light glow method boils down to the fact that: the luminous flux from the light source, passing through a narrow slit, turns into a thin, narrow beam. Then, with the help of a lens, it is directed to the surface under study at a certain angle. Reflected, the beam again passes through the lens and forms an image of the slit in the eyepiece. In this case, an absolutely flat surface will have a perfectly straight light beam (line), and a rough surface will have a curved one.
The shadow method is an improved and extended method of the light glow. It consists in the fact that: not far from the surface being studied, a ruler with a beveled edge adapts. The beam of light overcomes the same distance, however, as if with a knife, it is cut off by the edge of the ruler. At the same time, a shadow can be observed on the measured surface, the upper part of which exactly repeats the studied profile. With the help of a microscope, such an image is examined, analyzed and conclusions are drawn about the parameters and nature of the roughness.
Microinterference method - is implemented using a special measuring device, which consists of a measuring microscope and an interferometer. Using an interferometer, an interference pattern of the surface of the object under study is obtained with the curvature of the strips in the places of irregularities. The roughness parameters are then measured using a microscope.
the method of casts should be singled out separately , which is used to assess the roughness of various hard-to-reach surfaces, as well as surfaces with a complex structure. The cast method is the removal of negative copies of the surface using wax, paraffin or gypsum, as well as their subsequent examination with a probe or optical method. Thus, the cast method is not an independent method, but only a method associated with preparation for measurement. It is applicable only in conjunction with one of the methods for measuring roughness.