The Extensometer Newsletter – November 2018 / Issue 8

A Breakthrough in Non-Contact Axial Extensometers

Industry-Leading Resolution, Accuracy and Speed
Innovative Features for Unmatched Ease of Use

New Epsilon ONE™ optical extensometers are a major advance in non-contact axial strain measurement, solving the two big problems with video extensometers: accuracy at small strains and ease of use.



Epsilon ONE’s resolution, accuracy, and speed lead the industry, and enable Epsilon ONE to meet ISO 0,5 / ASTM B-1 accuracy classes when testing everything from composites and metals to elastomers (video). Additionally, Epsilon ONE is rated for non-contact strain control and use in fatigue testing up to 200 Hz.

Innovative features that increase testing throughput while maximizing performance include:

  • Instant Reset – ready to test in under 2 seconds (video)
  • Always Real-Time – post-processing is never required, even at the highest data rates
  • Laser Assist Alignment System – instant visual spot-check for specimen alignment and optics positioning

Epsilon ONE fits all types of materials testing machines and is patent pending.

Best-In-Class Performance

Having enough resolution and accuracy at small strains is crucial when measuring modulus, yield points and stress-strain curves of high-modulus materials. The same applies with non-contact strain-controlled testing. For example, Epsilon ONE’s resolution is typically <0.2 µm with a 1 Hz filter (typical for tensile testing), and <5 nm in low strain rate applications.



The key to Epsilon ONE’s excellent performance is a combination of technologies – optical design, telecentric lenses, fast processing algorithms, and advanced calibration techniques – all with high data rates, for example up to 3000 Hz, that can be filtered in real time.
  • Resolution: <0.2 µm with 1 Hz filter, <5 nm in low strain rate applications
  • Real-Time Data Rate: 300-3000 Hz
  • Absolute Accuracy: <±1 µm or 0.2% of value
  • Cyclic Testing: >200 Hz cyclic test frequency, waveform independent
  • Maximum Tracking Speed: >1500 mm/second

Unmatched Ease of Use



  • Always on, always ready: Unlike DIC systems, software interactions are unnecessary when running repetitive tests
  • Faster throughput with Instant Reset: Auto-start repetitive tests without touching the extensometer or software
  • Fully factory calibrated: Epsilon calibrates using the industry’s most comprehensive process to account for scaling, skew, lens distortion, and uneven lighting; no grids or bars are required for calibration
  • Cleaner workspace: No need for an additional computer and monitor; the included User Interface software has very low resource requirements and can run on the test machine’s computer
  • Optional Touch Interface: Access and control the Epsilon ONE without a computer (video)



Optical Extensometer Resources

Epsilon ONE applications
Epsilon ONE advantages
Epsilon ONE features and specs (see tabs)
Epsilon ONE videos
Learn about selecting your Field of View (Tech Note)
Learn about telecentric lenses (with Tech Note)



Next Steps

Learn more here

Contact us for a demo

See videos of Epsilon ONE in action



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