Reliable measurements and deposition control are critical to the success of ink jet applications. We report gravimetric and optical measurements of microdroplets that enable high-accuracy drop-on-demand (DOD) ink jet printing, which has been applied to the production of materials for testing trace and stand-off explosives detectors deployed at airports and other locations. The imprecision of solute mass deposition is typically less than 0.4 % while the combined standard uncertainty is less than 1 %. Applications include the production of trace explosives reference swipes, the manufacture of standard microspheres by drying droplets either in flight or on superhydrophobic surfaces, and the generation of trace explosives vapors. The gravimetric measurement capabilities of the system have also enabled testing and calibration of grayscale thresholding routines used in optical micro-dimensional analysis of droplets in flight.
Michael Verkouteren, Greg Gillen, Matthew Staymates, Jennifer Verkouteren, Eric Windsor, Marlon Walker, Cynthia Zeissler, Marcela Najarro, George Klouda, Tim Brewer, Jessica Staymates, Robert Fletcher, Julie Ott, Timothy Barr, Sarah Dickinson, Jessica Grander, Melissa Halter, Hannah Sievers, "Ink Jet Metrology: New Developments at NIST to Produce Test Materials for Security Applications" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP27), 2011, pp 705 - 708, https://doi.org/10.2352/ISSN.2169-4451.2011.27.1.art00077_2