The dust particle counter is an instrument for measuring the number and particle size distribution of dust particles per unit volume in a clean environment. It can be widely used in various provinces and municipalities drug testing institutes, blood centers, epidemic prevention stations, disease control centers, quality supervision institutes and other authoritative institutions, electronics industry, pharmaceutical workshops, semiconductor, optical or precision machining, plastics, painting, hospitals, environmental protection, Production companies and scientific research departments such as inspection offices. Particles in the air scatter under the illumination of light. This phenomenon is called light scattering. Light scattering is related to particle size, wavelength of light waves, refractive index of particles, and absorption characteristics of light by particles. However, in terms of scattered light intensity and particle size, there is a basic rule that the intensity of the scattered light of the particles increases as the surface area of ​​the particles increases. Thus, as long as the intensity of the scattered light is measured, the size of the particles can be inferred, which is the basic principle of the light scattering type particle counter. In fact, each particle produces a weak intensity of scattered light, which is a small pulse of light that needs to be amplified by a photoelectric converter to convert the light pulse into an electrical pulse with a large signal amplitude, and then through the electronic circuit. Further zooming in and discriminating to complete the counting of a large number of electrical pulses. At this time, the number of electric pulses corresponds to the number of particles, and the amplitude of the electric pulses corresponds to the size of the particles. The specific working principle of the dust particle counter: the light from the light source is focused by the lens group in the measuring cavity. When each particle in the air quickly passes through the measuring cavity, the incident light is scattered once to form an optical pulse signal. The optical signal is sent to the photodetector through the lens group 2, and is converted into an electrical pulse signal in proportion, and then amplified and screened by the instrument electronic circuit to pick up the required signal and display it through the counting system. It should be noted that although the instrument is called a "counter", the ability of the instrument to resolve particle size is more important. Since the counting of electrical pulses is simple, it is important to determine the size of the particles. Most blow dryers intended for home use have a DC or an AC motor. AC motors reduce noise output, making them a quiet option for early morning or late night hair-styling. If you live with someone else in cramped quarters, look for these quiet-running hair dryers. DC motors, on the other hand, are lighter in weight than AC motors and make it easier to blow dry longer hair without arm fatigue. Hair Blower,Salon Hair Dryer,Dc Motor Hair Dryer,Supersonic Hair Dryer Ningbo Meirou Electric Appliance Co.,Ltd. , https://www.mrhairstraightener.com