Figure 1a shows a slotted optical switch. An LED is mounted in a plastic housing, facing a phototransistor, but separated by a gap. If something moves into the gap, it blocks the light path between ...

Aging degradation and seismic damage of civil infrastructure pose a serious problem for society. One promising technology for monitoring the condition of structures is optical fiber sensing. By ...

Carbon nanotube: these structures have been used to create a new and flexible light sensor. (Courtesy: iStock/theasis) A flexible, ultrathin optical sensor that uses carbon nanotubes to convert light ...

I am always on the lookout for ideas for simple test and measurement instruments that can be used on my workbench. Over the years, I have built dozens of little test instruments and home lab ...

In 1978, Dr Kenneth Hill, a Canadian physicist, first demonstrated the Fiber Bragg grating (FBG), an optical sensor able to reflect narrow wavelengths of light. During the 1980s, the technology was ...