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The  four main constituents of Optics are:
Reflection, Refraction, Wave theory-&-Quantum theory
..
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Introduction
 

(A.K.A., the part everybody else skips)

 
.
--A Little History:
A Little-more-History:--

The science of Optics encompasses a body of knowledge accumulated over a span of, at least, three thousand years.

Optical "technology" dates back to distant antiquity: 1200 B.C., Exodus 38:8 tells how Bezaleel recast "the looking-glasses of the women" into a brass ceremonial basin, for the Ark and Tabernacle.

The Greek philosophers Pythagoras, Democritus, Empedocles, Plato, Aristotle, and others, evolved several theories of the nature of light.

300 B.C., the rectilinear propagation of light was known, as was the law of reflection enunciated by Euclid in his book Catoptrics.

424 B.C.: The burning glass (a positive lens) was alluded to by Aristophanes in his comic play, The Clouds.

In 50 A.D., Refraction was studied by Cleomedes. 

Claudius Ptolemy, in 130 A.D., tabulated measurements of the angles of incidence and refraction for several optical media.

Leonardo da Vinci (1452-1519) described the Camera Obscure.

When discussing the history of the Refracting Telescope, Galileo Galilei's (1564-1642), name first comes to mind; however, it isn't known who actually invented the refracting telescope. 

Records do show that a Dutch spectacle maker, Hans Lippershey (1587-1619), applied for a patent in October of 1608. 

Galileo, hearing of the invention, built his own telescope; grinding the lenses by hand. 

Around the same time, the Compound Microscope was invented by the Dutchman Zacharias Janssen (1588-1632). 

A Little of the Present Day & Beyond [*]

Optical Fibers, Optical Recording, and the ultimate, Optical Computing

Data transport using Soliton Pulses in Dispersion-Shifted Fiber
   Single Fiber: Errorless data transmission: 50 Gb/s, at over 19,000 km, No Repeaters

   Undersea Fiber Optic Cable: TAT-14  (map)

   The 15,000-mile cable, which incorporates dense wave division multiplexing (DWDM) with 16 wavelengths of STM-64 per fiber pair, will operate at a protected capacity of 640Gbps, with a total capacity of 1.3 Tbps; enough to transmit the content of more than 400 full length movie DVD disks every second: that is 1 DVD for every man, woman, and child on earth in less than 6 months.

Repeaters that amplify light using Erbium-doped Fiber Light Amplifier  EDFA
   40 THz bandwidth (12.56 bibles/sec)

10 Fsec pulses from Erbium-doped Fiber LASER
Pulse widths ~ 10 Femtoseconds (10 -15 sec)
Light travels 1/8th the thickness of a sheet of paper.
10 Fsec is to one second as one second is to 3.2 million years.

The next generation of computing--Optical Computing, will have CPU operations and bus speeds measured in THz, data paths >>1024 bytes wide. Logic operations will occur in ‘optical space’ as Soliton wave packets interact algebraically--the operations happen outside of silicon. The hardware: sub-micron LASERS communicating across sub-micron space, both transferring and processing data, stored in Terra-Byte optical storage. [*]


There is a relatively new fiber optic data transmission scheme that utilizes something called Soliton Pulses. These are very short bursts of light generated in an Erbium-doped Fiber LASER. Soliton light can be used to transmit data at rates in excess of 50 Gb/s, at distances over 19,000 km of Dispersion-Shifted Fiber, requiring no repeaters, and with no errors. This data rate is the equivalent of sending 6,200 bibles per second. At this rate, one bible could be sent to everyone on earth--6 9 people--in about 10 days. 

Light Amplifiers
In the case of repeaters, in a long-haul fiber: instead of converting the light into electrical signals, amplifying, correcting errors, retiming and retransmitting light pulses for the next 20 km span, an optical amplifier is used. It consists of about 30 meters of Erbium-doped fiber, assorted filters and beam splitters, and pumped by a 15 mW LASER diode operating at 1550 nm. This arrangement adds about 30 dB of gain with no appreciable noise. Also, the bandwidth of this amplifier is on the order of 40 THz. At this rate, one bible could be sent to everyone on earth, 5.5 9 people, in about 18 minutes. 

The Shortest LASER pulse, to date, is ~10 Femtoseconds (10 -15 sec). Light would travel 1/8th the thickness of a sheet of paper in that time. 

1 Fsec is to one second as one second is to 32 million years. 
 

[*]Forecasting the future of technology is a Fool's Errand. 

 
Optics have four main constituents: 
     1)_ Reflection
     2)_ Refraction
     3)_ Wave theories of light
     4)_ Quantum theories of light

<Return to Main Page>

 
   
....
A Little-more-History:
 
.
The science of Optics encompasses a body of knowledge accumulated over a span of, at least, three thousand years.

Optical "technology" dates back to distant antiquity
1200 B.C., Exodus 38:8 tells how Bezaleel recast "the looking-glasses of the women" into a brass ceremonial basin, for the Ark and Tabernacle.

The Greek philosophers Pythagoras, Democritus, Empedocles, Plato, Aristotle, and others, evolved several theories of the nature of light.

424 B.C.: The burning glass (a positive lens) was alluded to by Aristophanes in his comic play, The Clouds.

300 B.C., the rectilinear propagation of light was known, as was the law of reflection enunciated by Euclid in his book Catoptrics.

In 50 A.D., Refraction was studied by Cleomedes. 

Claudius Ptolemy, in 130 A.D., tabulated measurements of the angles of incidence and refraction for several optical media.

Leonardo da Vinci (1452-1519) described the Camera Obscure.

When discussing the history of the Refracting Telescope, Galileo Galilei's (1564-1642), name first comes to mind; however, it isn't known who actually invented the refracting telescope. 

Galileo, hearing of the invention, built his own telescope; grinding the lenses by hand. 

Records do show that a Dutch spectacle maker, Hans Lippershey (1587-1619), applied for a patent in October of 1608. 

Around the same time, the Compound Microscope was invented by the Dutchman Zacharias Janssen (1588-1632). 
 
 

 

Optical Fibers, Optical Recording, and Optical Computing
 
 <Return to Main Page>
 
 
   
..
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