Thursday 20 March 2025
The quest for faster, more precise, and more flexible interferometry has been ongoing for decades. Interferometry is a technique used to measure tiny changes in distance or shape by splitting light into two beams that are then combined to create an interference pattern. This pattern can be analyzed to determine the desired information. However, traditional methods often have limitations, such as limited resolution, slow data capture times, and restricted flexibility.
Researchers from the Fraunhofer Institute for Physical Measurement Techniques (IPM) have made significant progress in addressing these challenges by developing a synthetic-wavelength generator based on electro-optical single-sideband modulation. This innovative approach enables the creation of arbitrary synthetic wavelengths with values ranging from centimeters to meters, while also allowing for switching times below 30 milliseconds.
The key to this technology lies in the use of an electro-optic modulator, which can adjust the phase of light waves in real-time. This allows the researchers to generate synthetic wavelengths that are not limited by traditional methods, such as the use of multiple lasers or optical fibers. The resulting device is capable of producing a wide range of synthetic wavelengths, from 15 millimeters to 1500 millimeters, with unprecedented precision and speed.
One of the most significant benefits of this technology is its ability to adapt to complex surfaces and operating environments. Traditional interferometry methods often struggle with rough or irregularly shaped objects due to limited unambiguous measuring ranges and speckle effects. The synthetic-wavelength generator overcomes these challenges by providing a flexible and reconfigurable system that can be tailored to specific applications.
The researchers demonstrated the capabilities of their technology using two different samples: a machine-milled piece of metal with multiple sub-surfaces, and a set of commercially available toy building blocks made of plastic. In both cases, the device was able to produce accurate measurements of surface shape and deformation, even in the presence of complex surfaces.
The potential applications of this technology are vast and varied. It could be used for precision measurement tasks such as quality control in manufacturing, non-destructive testing, or medical imaging. The ability to quickly adapt to changing conditions also makes it an attractive solution for real-time monitoring and inspection tasks.
While there is still much work to be done to refine the technology, the Fraunhofer IPM’s synthetic-wavelength generator represents a significant step forward in the field of interferometry. Its flexibility, precision, and speed make it an exciting development with far-reaching potential.
Cite this article: “Synthetic-Wavelength Generator Advances Interferometry Technology”, The Science Archive, 2025.
Interferometry, Synthetic-Wavelength Generator, Electro-Optical Single-Sideband Modulation, Precision Measurement, Quality Control, Non-Destructive Testing, Medical Imaging, Real-Time Monitoring, Inspection Tasks, Flexible Systems.
