激光粒度分析儀測試粒度分布簡介

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激光粒度分析儀92454.com.cn是一種常用的測量儀器，具有測試速度快、重復(fù)性好、準(zhǔn)確性好、操作簡便等優(yōu)點，在粉體加工領(lǐng)域中得到了廣泛的應(yīng)用。激光粒度儀怎樣測試粒度分布呢?

Laser particle size analyzer (92454.com.cn) 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?

 

　　激光粒度分析儀是根據(jù)顆粒能使激光產(chǎn)生散射這一物理現(xiàn)象測試粒度分布的。由于激光具有很好的單色性和極強的方向性，所以在沒有阻礙的無限空間中激光將會照射到無窮遠(yuǎn)的地方，并且在傳播過程中很少有發(fā)散的現(xiàn)象。

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.

 

　　米氏散射理論表明，當(dāng)光束遇到顆粒阻擋時，一部分光將發(fā)生散射現(xiàn)象，散射光的傳播方向?qū)⑴c主光束的傳播方向形成一個夾角θ，θ角的大小與顆粒的大小有關(guān)，顆粒越大，產(chǎn)生的散射光的θ角就越小;顆粒越小，產(chǎn)生的散射光的θ角就越大。即小角度(θ)的散射光是有大顆粒引起的;大角度(θ1)的散射光是由小顆粒引起的。進一步研究表明，散射光的強度代表該粒徑顆粒的數(shù)量。這樣，測量不同角度上的散射光的強度，就可以得到樣品的粒度分布了。

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.

 

　　激光粒度分析儀92454.com.cn為了測量不同角度上的散射光的光強，需要運用光學(xué)手段對散射光進行處理。我們在光束中的適當(dāng)?shù)奈恢蒙戏胖靡粋€富氏透鏡，在該富氏透鏡的后焦平面上放置一組多元光電探測器，不同角度的散射光通過富氏透鏡照射到多元光電探測器上時，光信號將被轉(zhuǎn)換成電信號并傳輸?shù)诫娔X中，通過專用軟件對這些信號進行處理，就會準(zhǔn)確地得到粒度分布了。

In order to measure the intensity of scattered light in different angles, laser particle size analyzer (92454.com.cn) 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.