Why is it in the news?
- In the era of the COVID-19 pandemic, high-speed internet connections have become the lifeline for virtual interactions, enabling activities like video chats, online transactions, and remote learning.
- The internet’s functionality relies on sophisticated communication technologies that facilitate seamless connectivity in our increasingly digital world.
About Optical fibres
- Optical fibres are thin cylindrical strands of glass used for high-speed data transmission.
- They are about the diameter of a human hair and can carry various forms of digital information, including text, images, voices, and videos.
- Optical fibres enable long-distance communication almost at the speed of light.
- Working Principle of Optical Fibres: Light, as an electromagnetic wave, is guided through glass fibres using the principle of total internal reflection. When light passes through glass, its path bends due to the difference in refractive index between glass and air.
- Total internal reflection allows light to bounce within the glass walls, enabling the transmission of coded signals over long distances.
Components of Fibre Optic Communication System
Transmitter:
- Encodes information into optical signals.
- Utilizes rapidly blinking light pulses representing zeros and ones.
Optical Fibre:
- Carries the encoded signal over long distances.
- Light reflects within the glass walls, minimizing signal loss.
Receiver:
- Reproduces information from the encoded optical signal.
Benefits of Fibre Optic Cables
- High data-transmission rates, reaching several terabits per second in a single fibre.
- Insensitivity to external perturbations like lightning and bad weather.
- Suitable for diverse applications, including telecommunication, medical science, laser technology, and sensing.
Development of Fibre Optic Cables
- Jean-Daniel Colladon and Jacques Babinet demonstrated light’s propagation in narrow streams in the 19th century.
- In the 1920s, Clarence Hansell and John Logie Baird transmitted images through glass fibres.
- Harold Hopkins and Narinder Singh Kapany transmitted images using a bundle of optical fibres in 1954.
- In 1956, Lawrence E. Curtiss developed the first glass-clad fibres, paving the way for long-distance data transmission.
- In 1966, Charles Kao identified impurities in glass as the cause of signal attenuation, leading to improved fibre optic performance.
- In 1971, Corning Glass Works achieved low signal loss in a finished cable.
Manufacturing Process of Fibre Optic Cables
· Fibre-drawing technique involves preparing a high-purity glass rod (preform) with an engineered refractive index profile. · The preform is heated and drawn into a thin, long fibre, reducing diameter while maintaining length. · The drawn fibre is coated with a protective layer for strength and durability. |
Future of Fibre Optic Cables
- Widely used in telecommunication, medical science, laser technology, and sensing.
- The Government of India announced a national mission in 2020 to promote quantum technologies and applications.
- Fibre optic communication, along with quantum optics, is on the verge of a new era with expanding possibilities.