A coherent optical time-domain reflectometer (COTDR) using flexible all-digital orthogonal phase code pulse is proposed for distributed acoustic sensing. All-digital orthogonal phase code pulse with ...

CBP is seeking proposals from potential contractors for the FOCI contract to install and test fiber optic cables along the ...

Despite the widespread use of luminescence lifetimes in physical measurements, there seems to be no consensus on the best method for lifetime determination. Researchers in this field split into two ...

High time-resolution monitoring of nitrogen dioxide (NO 2) is of great importance for studying the formation mechanism of aerosols and improving air quality. Based on the Griess–Saltzman (GS) reaction ...

Laser light with an ultrastable frequency in the ytterbium ion optical clock at NPL. Credit: Andrew Brookes By comparing optical clocks in six different countries, researchers have taken a major step ...

A micro-displacement sensing head based on two aligned cleaved fibers inserted into an optical fiber ring and interrogated by an optical time-domain reflectometry is presented. The sensor ...

Optical clocks are now about 100 times more accurate than the best cesium clocks and can measure time so accurately that they would lose or gain less than one second over billions of years.