Laser particle size analyzer (www.jnwinner.com) is a common measuring instrument. It has many advantages, such as fast testing, good repeatability, good accuracy, easy operation and so on. It has been widely used in the field of powder processing. How can the laser particle sizer test the particle size distribution?
The laser particle size analyzer is based on the physical phenomenon that particles scatter the laser to measure particle size distribution. Because of the good monochromatic nature and strong directionality of the laser, the laser will reach infinity in the unlimited space without obstruction, and there is very little divergence during the propagation.
Show that the Mie scattering theory, when the beam particles encounter blocked, scattering phenomenon will occur as part of the light propagation direction, light scattering and propagation direction of the main beam will form an angle, angle and particle size on the size of the larger particles, the scattering light generated by the angle of the smaller particles; the small, scattered light from the angle of the greater. That is, small angle (theta) scattered light is caused by large particles; large angle (theta 1) scattered light is caused by small particles. Further studies show that the intensity of scattered light represents the size of the particle. In this way, the particle size distribution can be obtained by measuring the intensity of scattered light at different angles.
In order to measure the intensity of scattered light in different angles, laser particle size analyzer (www.jnwinner.com) needs to employ optical means to deal with scattered light. We placed a Fourier lens in the light in the proper position, placing a set of multiple photo detectors in the focal plane of the Fourier lens, the light scattering from different angles by means of Fourier lens on the multiple photoelectric detector, optical signal will be converted into electrical signals and transmitted to the computer. These signals are processed by special software, get the accurate size distribution.