Optical sensor of novel high-output all-semiconductor dust particle counter

Abstract

The invention discloses an optical sensor of a novel high-output all-semiconductor dust particle counter. An aspherical mirror, an entrance lens screen, an exit lens screen and a light trapping are arranged in sequence in the heading direction of the light beam sent out by a semiconductor laser light source, a spherical reflector, a lens screen and a photodetector are arranged in the direction perpendicular to the light path, and the photosensitive area and the photosensitive surface of the photodetector are respectively positioned at the two sides of the center of the spherical reflector and satisfy the object-image relationship in the geometrical optics, wherein the light source is a high-power semiconductor laser light source, the photodetector is a photodiode, and a gain adjustable preamplification circuit is arranged on the shell behind the photodetector. The invention improves the counting efficiency, and raises the counting efficiency and the particle size resolution of the instruments. Besides, the invention has the advantages of long service life of the instruments, good exchangeability of the instruments, low power consumption and low cost; moreover, the optical sensor has small size, which is beneficial to the micromation of the complete device.

Description

technical field

[0001] The invention belongs to cleanliness detection equipment, in particular to an optical sensor for a full-semiconductor dust particle counter with miniaturization, large flow, high signal-to-noise ratio, high particle size resolution, and high counting efficiency. Background technique

[0002] With the continuous improvement of people's requirements for air cleanliness, material purity and processing accuracy, the measurement technology of micro particles is particularly important. The dust particle counter is the main measuring instrument used to measure the particle size distribution by the light scattering counting method. The laser dust particle counter is based on the Mie scattering theory. The scattered light generated by a single particle in the illumination beam is the direct measurement object, and then the measuring instrument is used to distinguish the particle size of the particle to be measured according to the difference in the scattered li...

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