Terahertz-Band Cell Phones Could See Through Walls: But terahertz imaging devices require tons of energy and multiple lenses to focus light, so they are prohibitively large. Kenneth O, professor of electrical engineering at the University of Texas at Dallas, is developing new versions that would not require multiple lenses.
The key breakthrough was a new fabrication process using familiar complementary metal-oxide semiconductors, the CMOS chips that power most consumer devices. O and his team found they could build a specific type of high-speed diode, called a Schottky diode, in CMOS. These high-speed light devices can reach the THz range using standard CMOS manufacturing processes, which means they’d be fairly simple to integrate into existing devices — without major impacts on cost or size.