Researchers at the Massachusetts Institute of Technology have designed an optical filter on a chip that is able to process optical signals from an extremely wide light spectrum simultaneously, offering greater precision and flexibility for optical communication and sensor systems.
Optical filters are used to separate one light source into two outputs: unwanted wavelengths—colors—and desired wavelengths. However, current filters, both discrete and integrated, have disadvantages of expense and narrow spectrum coverage respectfully.
The researchers at MIT have designed the first on-chip (integrated) filter that matches the broadband coverage and precision performance of the bulky discrete filters, but can be manufactured using traditional silicon-chip fabrication methods.
“This new filter takes an extremely broad range of wavelengths within its bandwidth as input and efficiently separates it into two output signals, regardless of exactly how wide or at what wavelength the input is. That capability didn’t exist before in integrated optics,” says Emir Salih Magden, a former Ph.D. student in MIT’s Department of Electrical Engineering and Computer Science, currently an assistant professor of electrical engineering at Koç University in Turkey.
These filters could be critical in a variety of precision applications including high-precision spectroscopy and GPS pinpointing to the centimeter.
To learn more about this project, click here.