Sneezes, Rain Clouds and Ink Jets: Improved Accuracy in Measuring MicrodropletsScientists boost the

Sneezes, Rain Clouds and Ink Jets: Improved Accuracy in Measuring Microdroplets

Scientists boost the accuracy of optical microscopes to image microdroplets in flight and apply the method to analyze the concentration of plastic nanoparticles.
Sneezes, rain clouds, and ink jet printers: They all produce or contain liquid droplets so tiny it would take several billion of them to fill a liter bottle.
Measuring the volume, motion and contents of microscopic droplets is important for studying how airborne viruses spread (including those that cause COVID-19), how clouds reflect sunlight to cool the Earth, how ink jet printers create finely detailed patterns, and even how a soda bottle fragments into nanoscale plastic particles that pollute the oceans.
By improving the calibration of a conventional optical microscope, researchers at the National Institute of Standards and Technology (NIST) have for the first time measured the volume of individual droplets smaller than 100 trillionths of a liter with an uncertainty of less than 1%. That is a tenfold improvement over previous measurements.