A Long Pulse CuBr Vapor Oscillator for Laser Monitor Applications

The paper discusses the perspectives of application of a long pulse CuBr vapor oscillator for laser monitors. The influence of excitation conditions of the copper bromide vapor laser on the lasing pulse duration is discussed. It is revealed that increased pulse duration of lasing up to 200 ns and more is observed in unstable mode of the discharge. Laser monitors based on the long lasing pulse CuBr vapor oscillators can be demanded for distant objects monitoring

Radial distribution of a single-pass amplified radiation in the active elements of CuBr lasers

The paper presents the results of study of single-pass amplified radiation distribution of copper bromide vapor laser active elements used in high-speed laser monitors. The possibility of modifying the profile of a single-pass amplified light beam by changing the copper bromide vapor concentration is demonstrated. This means of influence on the radiation profile seems to be easiest due to implementation by varying only one parameter of operation. Gaussian, ring-shaped or flat profiles can be achieved depending on the temperature of the containers with copper bromide. The diameter of the beam becomes narrower when increasing the concentration of copper bromide vapor. This feature is characteristic of the discharge tubes as small (diameter 2.5, length 5 cm) and large (diameter 5 cm, length 90 cm) active volume

A mirror based scheme of a laser projection microscope

The paper discusses the design of a laser projection microscope with a mirror-based scheme of image formation. It is shown that the laser projection microscope with the mirror-based scheme of image formation is well suited for distant objects monitoring. This scheme allowed obtaining a field of view of more than 3 cm at the distance of 4 m from the brightness amplifier

Registration and Processing System of Digital Speckle Images

In this paper, we discuss an application of the method of laser-speckle correlation for studying the process of fibrin formation in blood plasma. A module for recording and processing speckle images based on a debugging kit for the Atxmega128A1 microcontroller has been developed. The results of testing the developed module as part of a laboratory setup based on a diode laser using standard reagents are presented. The developed device allows obtaining a curve characterizing the process of fibrin formation in blood plasma, with the use of which it is possible to determine the clotting time

Study of Aluminium Nanopowder Combustion by Method of Laser-Speckle Correlation

In this paper, we discuss an application of the method of laser-speckle correlation for studying the combustion process of aluminium nanopowder in air and its mixture of iron nanopowder. It is suggested to characterize the combustion process using the statistic parameter - correlation coefficient. The principle of observation is explained and the experimental schema for investigating is provided. The differences between aluminium nanopowder and its mixture with iron nanopowder are also considered

Synchronized Two-Camera Laser Monitor for Studying Combusting Powder Systems

In this paper, we offer a laboratory facility for in situ visualization of the combustion of ultrafine metal powders, which combines laser initiation and simultaneous high-speed recording of images of the flame of a burning material and a surface covered by a flame. Visualization of the surface through the flame is realized using a laser monitor—an optical projection system with brightness amplification. The proposed imaging system makes it possible to get more detailed information about the combustion process, in particular, to study the change in the surface through the flame in the area of laser initiation, and the propagation of heating and combustion waves over the sample, as well as to study the change in the surface reflectance during combustion. To study the area of laser initiation, it is proposed to simultaneously record images of a laser monitor with two cameras. The symmetry of the combustion wave front propagation and the combustion products’ formation during laser initiation of the nanoAl + Fe3O4 thermite mixture was demonstrated. The nature of propagation in the form of a ring is a consequence of the symmetry of the properties of the system under study, at the micro and macro levels

Speckle pattern processing by digital image correlation

Testing the method of speckle pattern processing based on the digital image correlation is carried out in the current work. Three the most widely used formulas of the correlation coefficient are tested. To determine the accuracy of the speckle pattern processing, test speckle patterns with known displacement are used. The optimal size of a speckle pattern template used for determination of correlation and corresponding the speckle pattern displacement is also considered in the work

Automated Coconut Chopping Machine

The paper explains the purpose, working principle, advantages and applications of the new machine named “Automated Coconut Chopper”. The main purpose to design this machine is to automate an activity of a farmer/labor i.e. chopping of green coconut in order to consume water inside it and also designed considering the two main factors safety and cost

Whole blood clotting time assessment by method of laser-speckle correlation

The paper presents the results of study of the coagulation process of the whole blood with anticoagulant using the method of laser speckle correlation. The clotting time dependence curves of the correlation coefficient have been presented and discussed. Analyzing the changing trend of these curves is possible to assess the clotting time, which prove the capability of using the method of laser speckle correlation for determining the diseases of blood coagulation

Preparation and properties of composite material based on hafnium diboride and aluminum

Hafnium diboride (HfB[2]) in aluminum matrix (Al) material was prepared by diffusion sintering of a mixture of hafnium diboride and aluminum micropowders. The effect of the hafnium diboride content (HfB[2]) in the aluminum matrix (Al) on sintering characteristics and properties of the samples is presented. The effect of microwave activation of the aluminum powders has been established. The diffusion sintering behavior was concluded. The material properties and structure were defined