Granularity centering measuring method utilizing CCD (charge coupled device) or CMOS (complementary metal-oxide-semiconductor) as photoelectric detector

Abstract

The invention discloses a granularity centering measuring method utilizing a CCD (charge coupled device) or CMOS (complementary metal-oxide-semiconductor) as a photoelectric detector. The method comprises the following steps: 1, adopting a CCD or CMOS as a multielement photoelectric detector, utilizing a power adjustable laser, and lowering the power of the laser before granularity of granules ismeasured, thus a low power laser beam is not saturated when being focused on the CCD or CMOS; and recording the pixel position of the laser spot on the CCD or CMOS, and taking the measured pixel of the spot as a scattering center position during granularity measurement; 2, adjusting the power of the laser to the limit power at which the pixel with a peak signal is not saturated, carrying out measurement, and recording the distribution of lights scattered by the granules; and 3, calculating according to the light scattering theory to obtain granularity distribution of the granules on the basisof the initially determined scattering center position. According to the invention, the defects that the traditional laser granularity instrument is complex in centering and the pixel is easily saturated or damaged when the CCD or CMOS is adopted as the photoelectric detector are solved, a hardware centering device is omitted, no concentric adjusting is required, and the granularity measurement of the granules can be realized.

Description

technical field [0001] The invention relates to a particle size measurement method of a laser particle size analyzer, in particular to a centering measurement method of a laser particle size analyzer. Background technique [0002] The laser particle size analyzer has been widely used in many fields. Its basic principle is that when a laser beam is incident on the particle sample to be measured, due to the scattering effect, the incident light will deviate from the original incident direction and scatter in all directions. The spatial distribution of light scattering is related to the size of the particles. When the particles are small, the forward scattered light is relatively weak, and when the particles are large, the forward scattered light is relatively strong. The laser particle size analyzer uses this principle to measure the distribution of scattered light in different directions, and then obtains the particle size distribution of the measured particles according...

AI Technical Summary

Problems solved by technology

This will also increase the complexity and cost of the instrument, so there are few commercial laser particle size analyzers that use area array CCD or CMOS as photodetection devices.

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