© Mark Ollig
In 1841, Jean-Daniel Colladon, a Swiss physicist, publicly demonstrated how a ray of light, traveling inside a curved arc of flowing water, would bend, thus becoming refracted.
He presented what is known as total internal reflection, which he described as “light guiding.”
“[It was] one of the most beautiful and most curious experiments that one can perform in a course on optics,” Colladon later wrote.
Moving ahead 135 years, AT&T engineers successfully sent and received information over a beam of light in 1976.
The engineers, producing rapid changes in a light source, learned it could code information within it using direct modulation through multiplexing laser frequencies within the modulated light, and guide it over a transparent, fiber-optic glass strand.
The information encoded within the laser light traveled over a fiber-optic telephone cable installed at AT&T’s research facility in Atlanta, GA.
The “laser” acronym means Light Amplification by Stimulated Emission of Radiation.
The two most common light sources for fiber-optic transmission are LED’s (light-emitting diodes), and laser diodes.
“It is a device which produces light. Tunable lasers can produce light of a single frequency, or visible color, in human terms. By turning the laser light signal on and off quickly, you can transmit the ones and zeros of a digital communications channel,” is the description of a laser I found in my trusty Newton’s Telecom Dictionary.
In 1976, an A-7 Corsair US military fighter jet replaced its copper wiring harness with a fiber optical link network.
The fighter jet’s optical link network weighed only 3.75 pounds and contained 13 fiber-optic cables spanning 250 feet.
The A-7 Corsairs’ previous copper wiring harness comprised 300 individual copper wire circuits, totaling 4,133 feet, and weighed 88 pounds.
Today’s fiber-optic systems installed in modern aircraft allow military pilots to make instantaneous decisions using high-resolution imaging systems, displays, and flight controls linked with fast fiber-optic networks providing real-time data.
In 1977, AT&T’s first commercial application of transmitting public telecommunications over a fiber-optic cable took place in Chicago.
During the late 1960s, and unbeknownst to the public, NASA installed certain classified fiber-optic technologies for the Apollo 11 moon mission.
Your investigative columnist did some research.
I discovered NASA’s lunar television camera used by the Apollo 11 astronauts on the moon’s surface in 1969, incorporated fiber-optic technology.
The use of fiber-optics inside the lunar television camera was classified as “confidential” in NASA’s “Lunar Television Camera Pre-installation Acceptance (PIA) Test Plan” document 28-105, dated March 12, 1968.
Stowed inside a compartment on the Apollo 11 lunar module “Eagle” descent stage was the lunar television camera.
Westinghouse Electric Corporation’s Aerospace Division developed and manufactured the Apollo Lunar Television Camera (part number 607R962).
The first lunar television camera remains on the moon’s surface, near the Apollo 11 landing site, in the Sea of Tranquility.
We had previously believed fiber-optic technology would not reach its data-capability bandwidth capacity for many years; however, this may no longer be the case.
According to the University of the Witwatersrand, Johannesburg, South Africa, today’s increases in data, coupled with the advances in information technology, will have troublesome repercussions on the current technology used to provide the bandwidth needed to transport data – even over fiber optics.
“Traditional optical communication systems modulate the amplitude, phase, polarization, color, and frequency of the light that is transmitted,” the news release from the university stated.
Researchers from this university began working with South Africa’s Council for Scientific and Industrial Research.
They demonstrated 100 separate light patterns (representing data) individually sourced through a single optical communications link.
The researchers created a computer hologram encoded with more than 100 light pattern configurations in multiple colors.
The light pattern configurations, being sent through an engineered liquid crystal, acted as a single spatial light modulator.
As this single light was transmitted, each light pattern was “demultiplexed,” meaning, the 100 individual light configuration patterns were extracted and sent to their unique designated locations.
All 100 light patterns were detected simultaneously.
Their next test involves demonstrating this new technology in a “real-world” situation using voice and video.
An increase in light patterns will allow for a sizeable expansion in available bandwidth for transmitting data.
The additional bandwidth will result in information being more efficiently “packed into light.”
Today, fiber optic cables provide the pathway for 1 Gbps (Gigabit per second) internet data speeds into businesses and residential homes.
We’ve come a long way from those 56 Kbps dial-up modems, where it might take a day to download a full-length movie.
Laboratory tests of data speeds (measured in bits) through a fiber optic cable have reached speeds from terabits per second (Tbps) into the petabits (Pbps).
Data speed of 1 Tbps equals 1,000 Gbps. 1 Pbps equals 1,000 Tbps, and 1 Pbps is equal to 1,000,000 Gbps.
When describing 1 gigabyte of information, the abbreviation 1 GB is used.
Remember, 8 bits of binary data equals 1 byte.
A NASA booklet, dated March 12, 1968, describing the “Lunar Television Camera,” is at http://tinyurl.com/lunarcam.
In this booklet, Section 1.1, “Security Classification,” includes the classified confidential mention of the fiber optics used with the lunar television camera.
Be safe out there.
