The possibility of developing a light-powered computer has remained a distant dream for developers and scientists for a long time now. Although ‘light’ has been the source of inspiration in computing, the idea of an all-optical computer still remains elusive. However distinct components running on support of light have started to make way into the personal computer step by step and the proposition of replacing the electrons trudging along inside copper wires with photons seems all the more attractive now. Since photons are the fastest particles in the universe, an optical computer can possibly process information at mind boggling speeds-much more than those of a supercomputer.

Since photons travel very fast through optical fibres and are not prone to huge losses through transmission or interference, they can be used to send different colored signals through the same wire thereby multiplying its capacity many folds. However as the fibres carry optical rays, they need components which can convert the photons to electricity which are generally processed by computers as information. These conversion components are expensive and has kept optical-data links from being used inside personal computers and servers.

This scenario seems to be changing for sure as more and more computers are outrunning their electrical wiring. Printers, hard drives and Screens are getting more demanding by the day in terms of speeds and processing capability. The greatest demanding devices are the processors which continue to expand their speeds exponentially and as a result the ‘interconnects’ between all these components are finding it very difficult to cope. But as we would find out, some of the biggest firms in the computing business are coming out with smart alternatives in this area.

Intel has developed one of these new interconnects which it calls Light Peak. It connects computers with other devices using high speed optical cables running speeds to the tune of 10 gigabytes per second-twenty times faster than a standard USB cable. Light Peak is expected to drive up demands for more powerful processors by making optical connections as pervasive as their wireless counterparts. The company has had to work out a smart cheap way of making converters that turn electrical signals into light and vice versa.

Engineers at HP have been facing a difficult time maintaining cooling temperatures at their energy hungry data centres. They have started working towards developing an optical replacement for the interconnects in ’server racks’ and for doing the same they are using waveguides which are essentially small plastic strips with highly reflective metallic walls with grooves embedded inside them. Researchers at HP have managed to cut costs by making waveguides with an injection-moulding system similar to that used to manufacture CDs on a large scale.

IBM too seems to have joined the race and scientists and engineers at the computer giant have started resorting to the use of interconnects to make super computers run faster. As we know that electrons need to be converted into photons in order to process information faster, IBM has started mounting optical fibre cables onto the chips which are used to control and guide traffic between a supercomputer’s many processors. It has used silicon to develop a fast and extremely thin photodetector to convert optical signals into electrical ones.

Experts however harbor enough reservations. They opine that optical transistors will have a difficult time competing with their electrical counterpart. And this wont be due to lack of available technology to facilitate conversions but the fact that using light to process information is like playing on a sticky wicket. This process requires quite expensive materials and lasers which demand more power than conventional transistors. So mass-produced optical processors remain a distant possibility as of now-but at least the beginning has begun.

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