Ultra-low flow velocity measuring device and method based on atomic force microscope

Abstract

The invention provides an ultra-low flow velocity measuring device and method based on an atomic force microscope. The device comprises an atomic force microscope, a laser emitter, a four-quadrant photoelectric detector and a flowing device. The flowing device is used for simulating flowing of liquid with the extremely low flowing speed, a long-arm probe of the atomic force microscope can make contact with the fluid to measure the fluid speed, and the laser emitter is used for emitting laser. And the four-quadrant photoelectric detector is used for detecting the laser reflected by the cantilever beam. According to the invention, a long-arm probe of the atomic force microscopy is utilized, the probe extends into the fluid, so that the probe is subjected to flow resistance to drive the cantilever to generate torsional deformation, the torsional deformation is recorded by the four-quadrant photoelectric detector, and the measurement of the velocity of the fluid with the extremely low flow velocity is realized. According to the method, the flow velocity of the fluid with the extremely low flow velocity can be measured by sensing the weak acting force of the fluid, the fluctuation of the measured fluid cannot be greatly influenced, and very high sensitivity can be achieved under the condition that the flow of the fluid is hardly influenced.

Description

technical field [0001] The invention relates to the field of atomic force microscope application technology, in particular to an atomic force microscope-based ultra-low flow rate measurement device and method. Background technique [0002] Atomic force microscope (AFM) is an optical instrument that can obtain the microscopic three-dimensional topography of the material surface by scanning the surface of the sample. During the detection process, one end of the probe cantilever is fixed, and the other end decorated with a needle tip is used to approach the sample. The cantilever is affected by the force between the needle tip and the sample, and the deformation or movement state changes. These changes are measured and recorded by optical methods. . In recent years, with the deepening of research, the atomic force microscope has developed from a traditional three-dimensional surface topography observation instrument to a measurement equipment for the weak force between the sam...

AI Technical Summary

Problems solved by technology

However, for the flow rate of some fluids with extremely low flow rates, such as the flow rate of blood in human blood vessels and the flow rate of medicinal liquid in hospital infusion tubes, traditional measurement methods are difficult to measure accurately and easily, and will cause large fluctuations in the flow of fluids

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