Common particle detection and imaging techniques include optical microscope with super high resolution, Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), and Atomic Force Microscope (AFM). Although the large-scale imaging instruments such as TEM, SEM and AFM can image nanoparticles clearly, they are expensive, bulky, and nanoscale imaging, which is overqualified for daily rapid detection of chemical particles , so this kind of instruments are not suitable for large-scale popular use. Historically commodity digital cameras have been cheaper but weren't applicable, but now there are better sensors and lenses available. The availability, portability, and low cost of this kind of electronic devices have made them one of the research hotspots for the rapid detection of chemical particles.