Nigeria and China will build the first-of-its kind baseline Interferometry to monitor earthquakes and volcanic eruptions in Nigeria and Sub-Saharan Africa.
Interferometry’ is a measurement method using the phenomenon of interference of waves (usually light, radio, or sound waves).
The measurements may include those of certain characteristics of the waves themselves and the materials that the waves interact with.
In addition, interferometry is used to describe the techniques that use light waves for the study of changes in displacement. This displacement-measuring interferometry is extensively used for calibration and mechanical stage motion control in precision machining.
By using two light beams (usually by splitting one beam into two), an interference pattern can be formed when these two beams superpose.
Because the wavelength of visible light is very short, small changes in the differences in the optical paths (distance travelled) between the two beams can be detected (as these differences will produce noticeable changes in the interference pattern).
Hence, optical interferometry has been a valuable measurement technique for more than a hundred years. Its accuracy was later improved with the invention of lasers.