11-06-2014, 12:45 PM
OPTICAL COMPUTING
INTRODUCTION
With the growth of computing technology the need of high performance computers (HPC) has significantly increased. Optics has been used in computing for a number of years but the main emphasis has been and continues to be to link portions of computers, for communications, or more intrinsically in devices that have some optical application or component (optical pattern recognition etc.)
WHY WE NEED OPTICAL COMPUTERS?
Rapid growth of the Internet
Network speeds currently limited by electronic circuits
Terabit speeds are required
Traditional silicon circuits have a physical limit
SMART PIXEL TECHNOLOGY
Smart pixel technology is a relatively new approach to integrating electronic circuitry and optoelectronic devices in a common framework.
The purpose is to leverage the advantages of each individual technology and provide improved performance for specific applications.
Here, the electronic circuitry provides complex functionality and programmability while the optoelectronic devices provide high-speed switching and compatibility with existing optical media.
DEVICES FOR OPTICAL COMPUTING
Logic gates :
Logic gates are implemented optically by controlling the population inversion that occurs to produce lasing. A controlling laser is used to control the population inversion thus causing switching to occur.
Holographic truth table:
Destructive interference with light to be emitted or not is based on phase relationship.
Logic based on gratings:
1 is represented by vertical grating causing light
0 is represented by horizontal grating causing darkness.
APPLICATION
High speed communications
Process satellite data.
Storage area Network
Optical crossbar interconnects are usSed in a synchronous transfer modes and shared memory multiprocessor systems.
CONCLUSION
Research in optical computing has opened up new possibilities in several fields related to high performance computing, high-speed communications. To design algorithms that execute applications faster , software development will have a major impact in the future and the ground rules for the computing may have to be rewritten.