Extreme UV Sources Fill the Gap
The electromagnetic spectrum has several regions where emitters, detectors, or both are not readily available. Terahertz and the far-infrared are prime examples. Even within the visible spectrum, much has been said about the “green gap” — the wavelength region between 500 and 600 nm where efficient and high-brightness solid-state sources were, until recently, hard to come by (Figure 1). Figure 1. An LDLS (laser-driven light source) module from Energetiq Technology Inc.,
Photonics Spectra, May 2018