METROMEET - 5th International Conference on Industrial Dimensional Metrology

Contact | Site Map | Español

• About METROMEET
  • About METROMEET
  • Technical Commitee
  • Call for Papers
  • Submit Abstract
  • Organiser
  • Contact
• Programme
  • Introduction
  • Programme
• Partners
  • Partners area
  • Sponsors
  • Exhibitors
  • Supporting Organizations
  • Support a contact moment
• Registration
  • Registration
  • Registration Form
• Accomodation
  • Accomodation
  • About Bilbao
  • Venue
• Press Room
  • Information
  • Media
  • Press Kit
• Previous Editions
  • Previous Editions
  • METROMEET 2010
  • METROMEET 2009
  • METROMEET 2008
  • METROMEET 2007
  • METROMEET 2006
  • METROMEET 2005

Programme

Interferometric length measurements

Prof. Erkki Ikonen
Metrology Research Institute Helsinki University of Technology - Finland

Presentation abstract

Automated interferometers for calibration of gauge blocks, line scales and step gauges are described. The applications include measurements of nanoscale glass standards and quality control of coordinate measuring machines. The gauge-block calibrator is a scanning interferometer with a white-light source and 633-nm He-Ne laser. The advantage of using white light interference is that no prior knowledge of the length of the gauge block is needed. The line-scale interferometer uses a dynamic measurement method with a microscope and a CCD camera as the graduation line detector. Elimination of alignment errors is essential for the line scale and step gauge interferometers. The combined standard uncertainties are between 50 and 100 nm for steel standards of 1 m in length. Results of comparison measurements are in agreement with estimated uncertainties of the interferometers.

Proposed contents of tutorial

Basics of interferometric length measurements

1. Electromagnetic waves (45 minutes)
-Maxwell equations
-wave equation
-plane waves and spherical waves
-intensity
-interference of parallel and almost parallel plane waves

2. Practical realizations of interference (45 minutes)
-Michelson interferometer
-longitudinal coherence
-spectrum and interferogram
-Fourier transform spectroscopy
-double slit experiment
-transverse coherence

3. Applications to dimensional measurements (45 minutes)
-characterization of surface shape
-cube corner for controlled scanning
-gauge block interferometer
-line scale interferometer
-step gauge interferometer
-evaluation of measurement uncertainty

I have given these lectures in my courses for more than 10 years. Interaction and discussion with participants is encouraged in a tutorial type of presentation, where it would be helpful to have some advance information on the participant's experience.

 

Information about the speaker

Erkki Ikonen received the M.Sc. and Dr.Sc.(Tech.) degrees in engineering from the Helsinki University of Technology, Finland, in 1982 and 1988, respectively. Until 1988, he was with the Department of Technical Physics, Helsinki University of Technology, where he was engaged in basic research of experimental physics. From 1988 to 1989, he was with the Electrical Engineering Laboratory, Technical Research Center of Finland. Since 1989, he has been with the Metrology Research Institute, Helsinki University of Technology, where he has acted as Professor of measurement science and technology from the year 1995. Since 2005, he has also been part-time Research Professor at the Centre for Metrology and Accreditation (MIKES). He has acted as the deputy chair of the European Metrology Research Program from 2007. His research for the last 20 years has been directed toward development of laser-based measurements, high-accuracy instruments for interferometric length determination, and improved methods for radiometric and photometric measurements.