Light Peak

Just found out some more information on another technology which is coming to mainstream use in 1 or 2 years which uses optical technology to deliver high speed data transmission between devices, similar to silicon photonics.

Description by Intel

Light Peak is a new high-speed optical cable technology designed to connect your electronic devices to each other. Light Peak delivers high bandwidth starting at 10Gb/s with the potential ability to scale to 100Gb/s over the next decade. At 10Gb/s, you could transfer a full-length Blu-Ray movie in less than 30 seconds. Optical technology also allows for smaller connectors and longer, thinner, and more flexible cables than currently possible. Light Peak also has the ability to run multiple protocols simultaneously over a single cable, enabling the technology to connect devices such as peripherals, displays, disk drives, docking stations, and more. . Light Peak components are expected to begin to become available to customers in late 2010, and Intel expects to see Light Peak in PCs and peripherals in 2011.

Existing electrical cable technology in mainstream computing devices is approaching practical limits for speed and length, due to attenuation, noise, and other issues. However, optical technology, used extensively in data centers and telecom communications, does not have these limitations since it transmits data using light instead of electricity. Light Peak brings this optical technology to mainstream computing and consumer electronic devices in a cost-effective manner.

How the silicon photonics link works

This is a great explaination of how the optical microchips work... from Intel..

The optical microchips that Intel is researching are made from silicon – just like conventional microchips. This offers the advantage of being able to use existing production systems and expertise spanning four decades in their manufacture. Furthermore, silicon is a practically inexhaustible resource. After oxygen, it is the next most common element on the Earth, and can be obtained from quartz sand.

An optical microchip functions in a similar way to a conventional chip, except that its conductor paths are not made from metal, and that data is not transferred in the form of electrons. Rather, photons are transported through the silicon in light ducts, referred to as waveguides. To a large extent, an optical microchip is made of three components: a modulator that converts electronic data into light, a laser which acts as a light pump to send the photons through the silicon, and a demodulator that converts the photons back into electronic impulses.

The electronic data is recoded into light pulses in the modulator. Theoretically, this is very straightforward, because digital data only occurs in two states, namely "zero" / "one", or "on" / "off". To put it simply, the modulator operates like a light switch which switches the laser on and off, thereby passing on the digital data in the form of photons. To enable the photons to be transmitted, it is necessary to have a certain type of laser, in this case a Raman laser4iv. Intel has developed a Raman laser composed of silicon and indium phosphide, which will be used on the company's optical microchips. The photons are converted back into electrons by the demodulator, the last missing component of an optical microchip. The demodulator is made up of a silicon core, but has a special germanium coating in order to absorb the light. When the laser pulses strike the demodulator, they are absorbed by the germanium layer, thereby causing electronic pulses to be created. These pulses are passed on to the silicon where they are amplified and can then be processed electrically.

Applications for Silicon Photonics

According to Intel, Silicon photonics will have applications across the computing industry. For example, at these immense data rates one could imagine a wall-sized 3D display for home entertainment and videoconferencing with a resolution so high that the actors or family members appear to be in the room with you.

Tomorrow's datacenter or supercomputer may see components spread throughout a building or even an entire campus, communicating with each other at high speed, as opposed to being confined by heavy copper cables with limited capacity and reach. This will allow datacenter users, such as a search engine company, cloud computing provider or financial datacenter, to increase performance, capabilities and save significant costs in space and energy, or help scientists build more powerful supercomputers to solve the world's biggest problems.

"This achievement of the world's first 50Gbps silicon photonics link with integrated hybrid silicon lasers marks a significant achievement in our long term vision of ‘siliconizing' photonics and bringing high bandwidth, low cost optical communications in and around future PCs, servers, and consumer devices" Rattner said.

Why Silicon Photonics...

So the biggest question asked is why silicon photonics?? According to many individuals in the computer industry it seems as though the traditional sense of transferring data over copper wires is reaching its intended limit. With computers and businesses needed more data faster and more efficiently, here steps in silicon photonics which can provide this further boost to transmission speeds needed.

Because silicon photonics is based on optical transmission which is not so really new to the communications world. However, the bulkiness and costs associated with implementing these in everyday devices is not cost effective.

So this is where Intel and the convergence of multiple technologies (laser, silicon) have come together to make this possible, and bring down the cost of implementation.