Method for measurement and 3D reconstruction of precipitation particles based on orthogonal dual-view imaging

A method for performing measurement and 3D reconstruction of precipitation particles based on orthogonal dual-view imaging, using a system comprised of

• two planar CCD/CMOS cameras, two pulse light sources, a high-speed line image sensor, and a continuous light source, which are connected with telecentric lens, a microprocessor unit (MPU), and a host computer, wherein
• the two planar cameras are placed facing towards the two pulse light sources respectively, two parallel light beams from the two pulse light sources are orthogonal to each other, an overlap region of the two light beams forms a 3D sampling space;
• the continuous light source, across from the line image sensor, generates a parallel light sheet that is projected onto the line image sensor, wherein the continuous light source, the line image sensor and the telecentric lens forms a wide sampling space, the light sheet is placed directly above the 3D sampling space;
• the two planar cameras, two pulse light sources and a line image sensor are connected to the MPU and timing sequences of the two planar cameras and two pulse light sources are synchronized precisely by the MPU, when particles pass through are detected by the line image sensor, the MPU generates and transmits an instruction sequence to trigger the image acquisition by the two planar cameras;
• the method comprising
• controlling the two planar cameras, by timing sequences synchronized by the MPU, and recording two 2D images of each particle at two orthogonal angles at the same time;
• reconstructuring a 3D image of each precipitation particle from the two orthogonal 2D images by using a pixel matching method;
• and
• calculating characteristics of the precipitation particles, including 3D sizes, axis ratio, orientation, fall velocity, and other characteristics based on the 3D images of the precipitation particles.