Far-Distance Moiré device


Displacement and vibration measurement with the Moiré technique

By superposing two Ronchi gratings with close pitches, a new periodic pattern, i.e., the so-called Moiré fringes, is generated with much greater pitch. The advantage of the Moiré fringes is its magnification compared to the constructing gratings pitch. Furthermore, it has a great sensitivity to movement and rotation of the primary gratings which leads to precise measurements.

Device Specification & Advantages
  • Far-distance and nondestructive measurement
  • Financially beneficial compared similar measurement devices
  • User-friendly Software based on R Programming languages
  • Simple physical method
  • Uncomplicated elements
  • Optics simplicity
  • Conventional optical/mechanical/electronic elements
  • Fast results achieving
  • Distance from target: up to 100 m
  • Focal length ∼1 m
  • Exit pupil diameter ∼ 20 m
  • First and second Grating with pitches ∼ 3 mm & 50 μm
  • CCD Sensor with 750 frame 750 frame/s , and Nyquist frequency ∼ (10-4_375)Hz 44444
  • 20 μm Displacement Precision from 76 m and 40 µm precision from ∼100 m
  • 6 m field of view from 80 m
Application of FDMM Device:
  • Displacement Measurements (Megastructures, buildings, Earth - Faults, compressors …)
  • Measurement of Structures vibration, structures damping and vibration modes
  • Vertical nodes displacement measurement
  • Sub-degree (mili degree) angle measurement
  • Measurement of atmospheric turbulence
  • Temperature profile measurement
  • Structure’s stress-strain measurements
  • Landslide measurement in geology application
Analysis of moving images
Device Style
Moiré Pattern 2
Moiré Pattern 1
Installation place on the bridge
Time shifting graph
Fluctuating Flow Chart
Samples of images received at intervals

About Us

Fanavari Kahroba Company started its activities in 2011 with manufacturing EMC Camera device and began to be a member of science and technology park of University of Tehran since 2012. Later on with devising thin film thickness measurement device and far distance Moiré measurement device, its official activities in precis measurement industry begun. Its optical surface topography measurement devices was introduced in 2014. Thanks to first ranked graduate elites, Kahroba’s company has devised several products with no international competitors. In addition, its products have the advantage of consumers support, precision calibration and being financially affordable for local manifactures. Among the highest valued policies of Kahroba’s company, science management can be mentions. Its most precious investment is expert graduate researchers. Reaching high shares of optical based measurement devices in the international market is one of the perspectives of Kahroba’s company. This aim not only does increase national economical growth, investment return and export, but also it does help to improve scientific foundation of the country and creating more job opportunities. In order to achieve this goal, Kahroba’s mission is devising high precise optical based measurement devices without international competitors based on national scientific experts. Academic customers, research projects, industrial customers, International exhibitions

16 Academic customers
25 Research projects
13Industrial customers
27 International exhibitions


Our Customers

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Contact Us

No 211,Building 2 ,Tehran University of Science & Technology Park,North Amir Abad , Tehran


021 86094102

021 86093205