:max_bytes(150000):strip_icc():format(webp)/laser10-56affd545f9b58b7d01f474a.jpg) |
| Argon laser emitting gases in test laboratory. |
Lasers
A Brief History of Lasers
Inventors and Advances in Laser technology
by Mary Bellis
The name LASER is an
acronym for Light Amplification by
the Stimulated Emission of Radiation.
It is is a device that emits
a beam of light through a process called optical amplification.
It distinguishes itself from
other sources of light by emitting light in a spatially and temporally coherent
manner.
Spatial coherence keeps the
beam within a narrow and tight path over long distances. This allows the energy
generated to be used in applications such as laser cutting and laser pointing.
Having temporal coherence
means that can emit light within a narrow spectrum to generate a light beam of
a specific color.
In 1917, Albert Einstein first
theorized about the process which makes lasers possible called "Stimulated
Emission."
He detailed his theory in a
paper titled Zur Quantentheorie
der Strahlung (On the Quantum Theory of Radiation).
Today, lasers are used in a
wide range of technologies including optical disk drives, laser printers and
barcode scanners.
They are also used in laser
surgery and skin treatments as well as cutting and welding.
Before the Laser
In
1954, Charles Townes and Arthur Schawlow invented the maser (microwave amplification
by stimulated emission of radiation) using
ammonia gas and microwave radiation.
The maser was invented before
the (optical) laser. The technology is very similar but does not use visible
light.
On March 24, 1959, Townes and
Schawlow were granted a patent for the maser. The maser was used to amplify
radio signals and as an ultra sensitive detector for space research.
In 1958, Townes and Schawlow
theorized and published papers about a visible laser, an invention that would
use infrared and/or visible spectrum light. However, they did not proceed
with any research at the time.
Many different materials can
be used as lasers. Some, like the ruby laser, emit short pulses of laser light.
Others, like helium-neon gas lasers or liquid dye lasers, emit a continuous
beam of light..
The Ruby Laser
In
1960, Theodore Maiman invented the ruby laser considered to be the first
successful optical or light laser.
Many historians claim that
Maiman invented the first optical laser.
However, there is some
controversy due to claims that Gordon Gould was the first and there is good
evidence backing that claim.
The Gordon Gould Laser
Gould
was the first person to use the word "laser."
Gould was a doctoral student
at Columbia University under Townes, the inventor of the maser.
Gould was inspired to build
his optical laser starting in 1958. He failed to file for a patent his
invention until 1959.
As a result, Gould's patent
was refused and his technology was exploited by others.
It took until 1977 for Gould
to finally win his patent war and receive his first patent for the laser.
The Gas Laser
The
first gas laser (helium-neon) was invented by Ali Javan in 1960.
The gas laser was the first
continuous-light laser and the first to operate "on the principle of
converting electrical energy to a laser light output." It has been used in
many practical applications.
Hall's Semiconductor Injection Laser
In
1962, inventor Robert Hall created a revolutionary type of laser that is still
used in many of the electronic appliances and communications systems that we
use every day.
Patel's Carbon Dioxide Laser
The
carbon dioxide laser was invented by Kumar Patel in 1964.
Walker's Laser Telemetry
Hildreth Walker invented
laser telemetry and targeting systems.
Laser Eye Surgery
New
York City ophthalmologist Steven Trokel made the connection to the cornea and
performed the first laser surgery on a patient's eyes in 1987.
The next ten years were spent
perfecting the equipment and the techniques used in laser eye surgery.
In 1996, the first Excimer
laser for ophthalmic refractive use was approved in the United States.
Trokel patented the Excimer
laser for vision correction. The Excimer laser was originally used for etching
silicone computer chips in the 1970s.
Working in the IBM research
laboratories in 1982, Rangaswamy Srinivasin, James Wynne and Samuel Blum saw
the potential of the Excimer laser in interacting with biological tissue.
Srinivasin and the IBM team realized that you could remove tissue with a laser
without causing any heat damage to the neighboring material.
But it took the observations
of Dr. Fyodorov in a case of eye trauma in the 1970's to bring about the
practical application of refractive surgery through radial keratotomy.
Mary Bellis has been writing about inventors since 1997. She also loves to
tinker (invent) and spends too much time in her workshop developing her ideas.
Experience
Forbes Best of the Web credits Mary for creating the number one online
destination for information about inventors and inventions. Her writing has
been reprinted and referenced to in numerous educational books and articles.
Her opinion and advice is requested by media outlets on a constant basis. In
addition, she has produced and directed a number of films, including a
documentary on Alexander Graham Bell, the inventor of the telephone, and has
worked as a curator specializing in computer generated art.
Education
Mary has two
degrees in film and animation from the San Francisco Art Institute. She is a
big fan of both history and technology and an avid reader of books and
periodicals on those topics.
Mary Bellis
I have a
passion for inventing and a deep respect for all inventors. I know firsthand
the difficulties that inventors face and I want to help by making the path from
idea to marketplace a clearer process.
You might also like:
Utraviolet Disinfection Systems
Questions & Answers
CLICK
HERE . . .
.
ULTRA VIOLET BACTERICIDAL LAMPS : Trojan, Sterilite, Wonderlite
CLICK HERE . . .
CLICK HERE . . .
No comments:
Post a Comment