18-05-2012, 11:12 AM
OPTICAL COMPUTER
[attachment=22315]
Introduction:
An optical computer is a computer that performs its computation with photons as opposed to the more traditional electron-based computation.
Optical computing includes the optical calculation of transforms and optical pattern matching.
Emerging technologies also make the optical storage of data a reality.
In an optical computer, electrons are replaced by photons, the subatomic bits of electromagnetic radiation that make up light
Light does not have the time response limitations of electronics, does not need insulators, and can even send dozens or hundreds of photon signal streams simultaneously using different color frequencies.
They are compact, lightweight, and inexpensive to manufacture, as well as more facile with stored information than magnetic materials.
By replacing electrons and wires with photons, fiber optics, crystals, thin films and mirrors, researchers are hoping to build a new generation of computers that work 100 million times faster than today’s machines
Background:
Optical computing was a hot research area in the 1980s.
Now, optical computers are back with advances in self-assembled conducting organic polymers that promise super-tiny all-optical chips.
Advances in optical storage device have generated the promise of efficient, compact and large-scale storage devices.
Another advantage of optical methods over electronic ones for computing is that parallel data processing can frequently be done much more easily and less expensively in optics than in electronics.
On the other hand for some applications in input output (I/O), such as image processing, by using a simple optical design an array of pixels can be transferred simultaneously in parallel from one point to another.
Fundamental concepts of optical computer:
An optical computer (also called a photonic computer) is a device that uses visible light or infrared (IR) beams, rather than electric current, to perform digital computations.
An electric current flows at only about 10 percent of the speed of light.
Thus, an optical computer, besides being much faster than an electronic one, might also be smaller.
Some optical integrated circuits have been designed and manufactured.
Some optical devices can be controlled by electronic currents, even though the impulses carrying the data are visible light or IR.
Some key optical components for computing:
The major breakthroughs on optical computing have been centered on the development of micro-optic devices for data input.
Conventional lasers are known as ‘edge emitters’ because their laser light comes out from the edges.
Also, their laser cavities run horizontally along their length.
A Vertical Cavity Surface Emitting Laser (VCSEL –pronounced ‘VIXEL’), however, gives out laser light from its surface and has a laser cavity that is vertical; hence the name.
POAC
optical computers for large data sets)
A new Programmable Optical Analogic Array Computer (POAC) has been developed at the Analogic and Neural Computing Laboratory of SZTAKI.
It optically identifies, clusters, discretizes, and classifies features of large data sets at high speed and with high parallelism.
It has proven to be an excellent device for tracking moving objects.
Smart pixel technology is a relatively new Approach to integrating electronic circuitry and optoelectronic devices in a common framework
The purpose is to influence the advantages of each individual technology and provide improved performance for specific applications.
Holographic Memory:
Technology developed by Call/Recall Inc. (San Diego, CA) could help bridge the gap between optical disk drives and holographic memories. Called 2-photon optical storage technology.
The Call/Recall systems under development use a single beam to write the data in either optical disks with up to 120 layers, or into 100-layer cubes of active-molecule-doped MMA polymer.
The focal point of the beam intersects a second beam formed by the second harmonic of the same beam at 532 nm. The second beam fixes the data spatially and temporally
Technical Description:
Present storage devices store one-dimensional information in a two-dimensional space.
Call/Recall’s Fredrick McCormick said the newer and older approaches offer different strengths. The YAG system can deliver higher-power pulses capable of storing megabits of data with a single pulse, but at much lower repetition rates than the Ti: Sapphire laser with its lower-power pulses.
Thus, it is a tradeoff. Call/Recall has demonstrated the system using portable apparatus comprised of a simple stepper-motor-driven stage and 200-microwatt He Ne laser in conjunction with a low-cost video came.
McCormick believes that a final prototype operating at standard CD rotation rates would offer BERs that match or slightly exceed conventional optical disk technology
Advanced research on optical computer and optical chip:
May 18, 1999: By using light and organic molecules to form materials in space, NASA scientists may improve both the speed and capabilities of computers.
Dr. Donald Frazier monitors a blue laser light used with thin-film materials.
The optical computers of the future will instead use photons traveling on optical fibers or thin films to perform these functions.
Right now scientists are focusing on developing hybrids by combining electronics with photonics
Electro-optic hybrids were first made possible around 1978, when researchers realized that photons could respond to electrons through certain media such as lithium niobate (LiNbO3)quartz.
Conclusion:
So we can make an Optical Computer by using previous things & many other things like as optical transistor, optical transformer, optical IC etc.
But we find out some conversion problems like conversion from photon to electrons and back.
This conversion is necessary now because we don’t have all optical versions of all switching devices required by a computer.
Researchers are going to remove this kind of problems.
[attachment=22315]
Introduction:
An optical computer is a computer that performs its computation with photons as opposed to the more traditional electron-based computation.
Optical computing includes the optical calculation of transforms and optical pattern matching.
Emerging technologies also make the optical storage of data a reality.
In an optical computer, electrons are replaced by photons, the subatomic bits of electromagnetic radiation that make up light
Light does not have the time response limitations of electronics, does not need insulators, and can even send dozens or hundreds of photon signal streams simultaneously using different color frequencies.
They are compact, lightweight, and inexpensive to manufacture, as well as more facile with stored information than magnetic materials.
By replacing electrons and wires with photons, fiber optics, crystals, thin films and mirrors, researchers are hoping to build a new generation of computers that work 100 million times faster than today’s machines
Background:
Optical computing was a hot research area in the 1980s.
Now, optical computers are back with advances in self-assembled conducting organic polymers that promise super-tiny all-optical chips.
Advances in optical storage device have generated the promise of efficient, compact and large-scale storage devices.
Another advantage of optical methods over electronic ones for computing is that parallel data processing can frequently be done much more easily and less expensively in optics than in electronics.
On the other hand for some applications in input output (I/O), such as image processing, by using a simple optical design an array of pixels can be transferred simultaneously in parallel from one point to another.
Fundamental concepts of optical computer:
An optical computer (also called a photonic computer) is a device that uses visible light or infrared (IR) beams, rather than electric current, to perform digital computations.
An electric current flows at only about 10 percent of the speed of light.
Thus, an optical computer, besides being much faster than an electronic one, might also be smaller.
Some optical integrated circuits have been designed and manufactured.
Some optical devices can be controlled by electronic currents, even though the impulses carrying the data are visible light or IR.
Some key optical components for computing:
The major breakthroughs on optical computing have been centered on the development of micro-optic devices for data input.
Conventional lasers are known as ‘edge emitters’ because their laser light comes out from the edges.
Also, their laser cavities run horizontally along their length.
A Vertical Cavity Surface Emitting Laser (VCSEL –pronounced ‘VIXEL’), however, gives out laser light from its surface and has a laser cavity that is vertical; hence the name.
POAC
optical computers for large data sets)A new Programmable Optical Analogic Array Computer (POAC) has been developed at the Analogic and Neural Computing Laboratory of SZTAKI.
It optically identifies, clusters, discretizes, and classifies features of large data sets at high speed and with high parallelism.
It has proven to be an excellent device for tracking moving objects.
Smart pixel technology is a relatively new Approach to integrating electronic circuitry and optoelectronic devices in a common framework
The purpose is to influence the advantages of each individual technology and provide improved performance for specific applications.
Holographic Memory:
Technology developed by Call/Recall Inc. (San Diego, CA) could help bridge the gap between optical disk drives and holographic memories. Called 2-photon optical storage technology.
The Call/Recall systems under development use a single beam to write the data in either optical disks with up to 120 layers, or into 100-layer cubes of active-molecule-doped MMA polymer.
The focal point of the beam intersects a second beam formed by the second harmonic of the same beam at 532 nm. The second beam fixes the data spatially and temporally
Technical Description:
Present storage devices store one-dimensional information in a two-dimensional space.
Call/Recall’s Fredrick McCormick said the newer and older approaches offer different strengths. The YAG system can deliver higher-power pulses capable of storing megabits of data with a single pulse, but at much lower repetition rates than the Ti: Sapphire laser with its lower-power pulses.
Thus, it is a tradeoff. Call/Recall has demonstrated the system using portable apparatus comprised of a simple stepper-motor-driven stage and 200-microwatt He Ne laser in conjunction with a low-cost video came.
McCormick believes that a final prototype operating at standard CD rotation rates would offer BERs that match or slightly exceed conventional optical disk technology
Advanced research on optical computer and optical chip:
May 18, 1999: By using light and organic molecules to form materials in space, NASA scientists may improve both the speed and capabilities of computers.
Dr. Donald Frazier monitors a blue laser light used with thin-film materials.
The optical computers of the future will instead use photons traveling on optical fibers or thin films to perform these functions.
Right now scientists are focusing on developing hybrids by combining electronics with photonics
Electro-optic hybrids were first made possible around 1978, when researchers realized that photons could respond to electrons through certain media such as lithium niobate (LiNbO3)quartz.
Conclusion:
So we can make an Optical Computer by using previous things & many other things like as optical transistor, optical transformer, optical IC etc.
But we find out some conversion problems like conversion from photon to electrons and back.
This conversion is necessary now because we don’t have all optical versions of all switching devices required by a computer.
Researchers are going to remove this kind of problems.