fibre optics 
plural noun [treated as singular]
1The use of thin flexible fibres of glass or other transparent solids to transmit light signals, chiefly for telecommunications or for internal inspection of the body.With the crash of the telecom sector, its investments in fibre optics capacity and other telecommunications ventures turned out to have been very expensive....
- Alcatel is divided in five business segments, comprising networking, the Internet and fiber optics, the enterprise and consumer sectors, telecoms components and energy.
- By the 1990s, satellite transmissions, cable television, digital facsimiles, fiber optics, and the Internet put the vast majority of Americans within reach of a global network of technological systems.
1.1 [treated as plural] Fibres and associated devices used in fibre optics.Because fiber optics are so flexible and can transmit and receive light, they are used in many flexible digital cameras for the following purposes....
- They use fibre optics to shine light into the body.
- Taiwan must do more to safeguard telecommunications, fiber optics, energy supplies and major transportation arteries, and should consider allowing private agencies to assist in national defense, he said.