Optical system for simple and convenient detection of particle size and shape

Abstract

The invention discloses a simple and convenient optical system for detecting the size and shape of particles. After the laser beam is homogenized by an optical fiber, a parallel beam with good uniformity is formed, and is irradiated along the main axis direction of the spherical cavity mirror system through a reasonable optical path layout. Into the rotationally symmetrical elliptical cavity mirror, and the sample gas flow converges at a focal point of the rotationally symmetrical elliptical cavity mirror, the sample gas flow is introduced along the direction perpendicular to the main axis of the system, and the forward scattered light signal of the particle is received by a photomultiplier tube, which is used as a particle Primary signal for size measurement. Scattered light other than the forward direction shoots to another focal point of the rotationally symmetrical elliptical cavity mirror in a large angle range, and a flat CCD is placed on the objective mirror plane behind the focal point, which is mainly used to detect the shape information of the particle size. The invention has ingenious layout, reasonable structure and good working effect.

Description

[0001] The present invention is a divisional application with application number: 201310307346.1, title: "Optical System for Detecting the Size and Shape of Particles Using a Rotationally Symmetric Elliptical Cavity Mirror", and filing date: 2013.7.22. technical field [0002] The invention relates to an optical sensor. Background technique [0003] Particle detection technology plays a vital role in scientific research, industrial sites, and atmospheric environment monitoring. Its detection technologies mainly include optical method, electrical method, and kinetic method. Among them, optical method is the most widely used for its wide measurement range, no contact with samples, fast, automatic and real-time. Typical instruments such as Coulter, Climet and ROYCO particle counter, domestic laser particle counter, etc. However, these instruments can only be used to measure the size of the particles, and the detection of the shape is rarely involved; not only that, but these i...

AI Technical Summary

Problems solved by technology

However, these instruments can only be used to measure the size of particles, and the detection of the shape is rarely involved; not only that, but these instruments also have the defects of limited acceptance angle range and poor light uniformity in the photosensitive area

For this reason, in the patent [CN201110346535.0], an optical sensor with a rotationally symmetrical elliptical cavity mirror is designed to measure the size and shape of particles. The uniformity of light has also been improved to some extent, but because the large-angle scattered light receiver only uses three photocells located at the vertices of the triangle, the amount of information collected is too small, which affects the detection accuracy of the shape, and also has a certain degree of difficulty in the detection of the size of the particles. Influence; In addition, the optical path layout adopted in this design to improve the beam uniformity is complex and easily affected by transportation, etc.

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