the world’s first composite DFOS sensor with strain range up to 4% and elasticity (E = 3 GPa) not influencing the structural behavior of monitored structure

EpsilonSensor enables accurate strains and precise crack measurements over its entire length due to the perfect bonding with the specimen. Specially selected composite material provides unique strain reading precision and sensitivity. EpsilonSensor is a perfect solution for laboratory applications, designed for direct embedding into the newly-designed structural members (made of concrete or soil) or to be installed within existing structural members (e.g. reinforced or prestressed concrete girders). Lightweight, low bending radius and extremely low stiffness allow the sensor to be installed easy and to not influence the behavior of the specimen.

Sensor advantages:

  • STRAIN AND CRACK MEASUREMENT ALONG THE ENTIRE LENGTH of the sensor, optionally also temperature
  • NO SENSOR INFLUENCE on the monitored structural member (negligible stiffness)
  • SHARP and PRECISE view of any local phenomena, especially cracks in concrete
  • EASY INSTALLATION – lightweight sensor, ready to use when unrolled from the drum
  • RESISTANT TO ENVIRONMENTAL CONDITIONS, including electromagnetic fields and lightning strikes


  • LABORATORY REASERCH – especially crack observation in concrete
  • STRUCTURAL HEALTH MONITORING of engineering structures
  • reinforced and prestressed CONCRETE specimens

Application of DFOS strain Sensors for the structural health monitoring of real engineering structures allows for strain measurements over the entire length with a spatial resolution starting from 5 mm. The key thing is to use sensors that are accurate and reliable. EpsilonSensor provides new opportunities in the quantitative and qualitative assessment of strains and cracks in concrete. It allows for the precise detecting the cracks locations and estimating their actual width during changing environmental conditions over the long term.

Technical specifications:

Strain measurement resolution1,0 µɛ
Strain measurement range±4%
Elastic modulus3 GPa
Operating temperature-20 to +80°C (extended range on request)
Sensor diameterstandard Ø 3 mm
Sensor weight13 kg/km (for Ø 3 mm)
Sensor materialPLFRP (polyester fiber + epoxide)
Scattering usedRayleigh, Brillouin or Raman
Method of deliverycoils or straight sections
Sensor lengthany length made to order