Phase rainbow refractometry for accurate droplet variation characterization

Area of Science:

• Optical physics
• Nanotechnology
• Fluid dynamics

Background:

• Accurate measurement of droplet size and its variations is crucial in various scientific fields.
• Existing methods often lack the precision to detect nanoscale changes in droplet diameter.

Purpose of the Study:

• To develop a one-dimensional phase rainbow refractometer for precise trans-dimensional measurements.
• To accurately measure micrometer-scale droplet sizes and nanoscale diameter variations.
• To investigate the relationship between phase shift in rainbow ripples and droplet size changes.

Main Methods:

• Development of a one-dimensional phase rainbow refractometer.
• Utilizing a telecentric one-dimensional rainbow imaging system to record phase-shifting rainbow images.
• Conducting experiments on evaporating monodispersed droplet streams.

Main Results:

• The developed refractometer accurately measures droplet size on the micrometer scale.
• The instrument can detect tiny droplet diameter variations down to the tens of nanometers.
• The dependence of phase shift on droplet variations was successfully revealed.

Conclusions:

• The one-dimensional phase rainbow refractometer is a capable tool for measuring droplet diameter and refractive index.
• This technology enables precise detection of nanoscale droplet diameter changes.
• The refractometer offers a new method for studying dynamic droplet behavior.