Terahertz reflectometry characterizes coats of paint without damaging them
A father-and-son research team at Applied Research and Photonics (Harrisburg, PA) has developed a technique that uses terahertz reflectometry to measure the thickness of paint layers (for example on cars) to a tens-of-nanometers accuracy; the paint is not damaged by the measurement. The technology could potentially be useful also for identifying lead paint, and even for cancer detection and examination of art artifacts.
The researchers will describe their work at CLEO: 2014 (June 8-13; San Jose, CA).
Layer thickness and other characteristics
The terahertz radiation penetrates the paint layers (which are each tens of microns thick) and is partially absorbed and partially reflected with an intensity that depends on the layer thicknesses.. This method can also be used to estimate the dimensions of any particles down to sizes of 25 nm added to the paint.
Terahertz reflectometry can be used to make sure that the overcoat does not penetrate the layers below. The method can also help companies analyze how their paints react with different surfaces, such as plastic, wood, or metal.
The researchers, Anis and Aunik Rahman, are now configuring the technique to allow analysis of the structure of skin as a way to help diagnose early stages of skin cancer such as melanoma and basal cell carcinoma. With the addition of spectroscopy to measure the different wavelengths of reflected beams, this technique can be used to analyze the structure of skin layers and determine if they are healthy or diseased.
The instrument is ready for commercialization and Rahman says they are currently looking for partners to help bring it to market.
Presentation AW3H.4, titled "Terahertz reflectometry of multi-layered paint thicknesses and estimation of particle sizes," will take place Wednesday, June 11, at 5:15 p.m. in Executive Ballroom 210H of the San Jose Convention Center.
John Wallace | Senior Technical Editor (1998-2022)
John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.