- Safety evaluation of structures like tunnels

  - Measurement of tunnel convergence and crown settlement

  - Siultaneously measuring both angle and displacement(length)

  - Measuring based on the combination of vector diagrams

<Principle based on the combination of vector diagrams>

  - Designed and applied special installation jig for FBG Extensometer to install as the shape of tunnel

  - High accuracy of measurement

  - No effect of electromagnectic waves

  - High sensitivity due to the use of wavelength setting bolts 

  - Easy to install on a curved surface or slope by applying ball joints

  - Easily replaceable and reusable

   - Measurement range :Decision on the use

  - Gauge length : 1,000 mm (Decision on the use)

  - Resolution : ¡¾ 0.05 %F.S (Full Scale)

  - Accuracy : ¡¾ 0.25 %F.S

  - Reflectivity : ≧ 70 %

  - Operating temperature : - 20 ~ 80 ¡É

  - FWHM (-3dB point) : ≦ 0.1 nm

  - Wavelength range : 1,511 ~ 1,584 nm

    ¡Ø Choose favorable wavelength from the following set division