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Theodore D. Doiron (Assoc)

Dr. Doiron is a member of the Dimensional Metrology Group since 1983, and Group Leader since 2002.

Computer Vision:

  • Designed and built a computer vision based station for both tool form measurement and tool setting for very high accuracy turning stations.
  • Used computer vision to automate the NIST grid plate calibration system.
  • Developed robust (Hough) edge finding algorithms for images with as much as 50% noise.
  • Used least median fit algorithms to analyze shapes of noisy lines in images of crosses and circles on grid plates.
  • Developed non-contact method based on diffraction patterns to measure the diameter of very fine wires.

Dimensional Metrology:

  • Designed and implemented a new statistical process control and measurement assurance system for dimensional calibrations such as gage blocks, cylinders and thread wires.
  • Built a prototype micrometer which improves the accuracy and efficiency of thread and gear wire calibrations.
  • Built special micrometer to measure optical fiber diameters which is used to calibrate reference standards for industry.
  • Developed 1 and 3 day seminars on dimensional metrology and gage block calibration for industrial inspection personnel.

Coordinate Measuring Systems:

  • Project coordinator for development of a new integrated coordinate measuring system incorporating fast contact and non-contact probe systems.

Other Current Research Projects:

  • Development of a dilatometer to measure the coefficient of thermal expansion of gages between 15 °C and 25 °C.
  • Performed a number of studies of the temporal stability of materials in use in dimensional metrology, including aluminum, steel, brass, silicon carbide, beryllium and gage steels.
  • Developed methods to make corrections for elastic deformation of gages.&
  • Working with the Justice Department on the metrology of scales used in forensic photography.

University Involvement: Thesis advisor for Master's Degree students from U. of North Carolina at Charlotte, American University, Howard University, and Federal University of Santa Catarina-Brazil.


  • Department of Commerce Gold Medal for work on standard measurements of optical fiber diameter.
  • Department of Commerce Silver Medal for development of standard grid plate for semiconductor industry.
  • Two NIST Bronze Medals for development of measurement methods.
  • Two Vice Presidential Hammer Awards for development of a gear measurement laboratory at the DOE Y-12 plant and the development of a NIST/DOE joint effort for very high accuracy coordinate measuring machine calibrations.
  • Best Paper Awards from both NCSL International and the Measurement Science Conference.


Sphere Diameter Interferometry with Nanometer Uncertainty

Eric S. Stanfield, John R. Stoup, Michael P. Braine, Theodore D. Doiron
In this paper we present both the design details and uncertainty budget for a National Institute of Standards and Technology (NIST)-developed high-accuracy

Dimensional Review of Scales for Forensic Photography

Massimiliano Ferrucci, Theodore D. Doiron, Robert M. Thompson, John Jones, Adam J. Freeman, Janice A. Neiman
Scales for forensic photography provide a geometrical reference in the photographic documentation of a crime scene. A common scale used by investigators is a
Created October 9, 2019, Updated December 8, 2022