I have read the posts on this board for many months now but usually do not feel inclined to correspond as I feel I can add nothing constructive to well versed arguments commonly seen. However, every now and again, someone will post a comment or opinion which I feel I can help or expand upon. Recently there have been comments on the capacity of POET chips with regard to its mixed signals capacity and felt it important that those investing should understand its importance.

First, it’s important to understand that POET chips, because of the basic substrate’s inherent properties (Gallium Arsenide) can deal with incoming inputs into a chip much faster than the vastly more common Silicon. Also it is very much more resistant to interference and damage from extraneous radiation (it’s why it can be used in space programmes).

Secondly, it’s important to understand what inputs a chip is likely to receive and this is complex. Most of us are aware of the various waves around us, for example, radio waves, light waves, x-rays, gamma rays, infra-red waves, ultra violet, microwaves. These waves all arise in a spectrum know in physics as the electromagnetic spectrum. They all travel at the speed of light but the wave can vary in frequency (how many peaks of the wave occur in a second) and wave length (the distance between each wave peak). Because the speed of light is constant in any medium (such as a vacuum) the relationship between frequency and wavelength is mathematical. Also, quantum theory dictates that these waves are clumped together in a discrete particle known as a photon and that they have no mass but do have energy (and momentum) this is the so called wave-particle duality theory. So the higher the frequency the more energy a photon carries. Thus, a radio wave has small energy whereas x-rays have high energy (it’s why we need protection when having an x-ray because these energetic photons can damage tissues and kill cancer cells).

There are other waves, for example, sound waves. These waves are pressure changes in the air and are transmitted for example to our ear and then to the brain as nerve impulses. Whereas light from an image travels as photons to the retina of our eye and then to the brain. A microphone can pick up the pressure changes and changes the pressure waves into electrical current and with amplification to a speaker. In the digital world, by rapidly sampling the wave, it can change the wave into a series of binary numbers which a chip can handle by storing numbers in a memory and reuse them to recreate a wave for a loudspeaker. It can also manipulate these numbers and change the sound heard on a loudspeaker.

So a chip can receive a variety of signals from various sources, convert them to binary digits, store and reuse them and, with the aid of a programme can get various responses in the form of an output. So, think of an engine management system. Various sensors can tell a microprocessor about temperature, carbon dioxide output, fuel/air mixture, valve and piston timing and a host of other inputs. A programme can adjust these, via a microprocessor, to produce optimum performance by instructing relevant part of the engine on how to behave. But, think of the processor inputs, they may be digital, or waveforms and there will be lots of them.

Now, here’s the POET bit. Because, it uses light as an internal transfer mechanism, all these digits moving around the processor are transferred at light speed. The outputs too, can transfer at light speed outside the processor. Now, here’s the last fact. Silicon can’t do this because it transfers information using electrons (they the negative elemental particles of an atom). They do have mass, unlike light, and move much more slowly and when they do so produce heat. Fundamentally, our POET processor, shifts information at the speed of light (nothing in the universe goes faster) and does so cooler. It can, therefore, do vastly more processing in a given time than a Silicon chip of the same gate length. It’s also likely, in the smaller gate lengths, that a POET chip can be produced as a system on chip (SoC) to include everything you require to monitor a system or get a computer to function on one processor. So whatever signals it receives (mixed signals) it can process and output at the speed of light and very high clock speeds. That means it can have lots of advantages in almost any industry you care to think of because superfast processing on one microprocessor is much cheaper than lots of processors linked together on a motherboard.

I do not know how far down the road this company is because we have not been told yet. We know they are close to producing working examples and the programmes to design and manufacture them. Just wait a bit more, try not to be too anxious about announcements and please understand, in the complexity of all this, perfect time keeping is simply not possible.

David