Microscopic examination grain size of reduced iron powder

The range of powder size value measured by light microscope

The resolution of an optical microscope can reach 0.2 micron under ideal circumstances, which is related to the wavelength of the light source and the numerical aperture of the lens. However, in practical application, the particle size measurement range of an optical microscope is 0.8~150 micron, and the particle size of a powder can only be observed and measured by electron microscopy and other methods. 

Method for measuring particle size of powder by optical microscope

As the reflected light optical microscope can only measure the particle size is greater than 5 micron particulate matter, thus granularity analysis usually work with transmission light microscope in order to calculate grain size, on the microscope eyepiece with a microscopic scale, scale should be calibrated in advance before using there are three kinds of commonly used to analyze the microscopic scale: 

(1) linear scale with reticle;

(2) network microscale;

(3) Pattern microscopic scale

The principle and advantages and disadvantages of measuring powder particle size by microscope

Microscope method of measuring the performance of the particle size, the particle size of projection symmetry good spherical particles (such as atomized powder) or cube particles can be directly calculated on diameter or length but for irregular non spherical particles, can't use directly computing method, must consider the different methods of said microscope method operation is the chief drawback of complicated and arduous