LASER: Its Prevalence and Prominence
Executive Summary
Light Amplification by Stimulated Emission of Radiation
(LASER) is a device that is capable of generating an intense beam of coherent
monochromatic light that can travel over large distances in a specific
direction without dispersing (Dasgupta, 2002). Laser light is produced through
the process of stimulated emission, where photons are released from excited
atoms or molecules and undergo pumping such that energy is introduced into the
laser cavity to produce an electromagnetic field. Electromagnetic waves reflect
back and forth between the mirrors inside the laser cavity, stimulating further
emission of photons with the same phase and frequency that eventually results
in an abrupt burst of coherent radiation when the atoms are discharged in a
rapid chain reaction (Rouse, 2005).
The prevalence of laser in our contemporary society is
characterized by its widespread presence across various industries while its
prominence is seen in its increasing importance as a tool harnessed within
these different sectors. The context for the prevalence and prominence of laser
could be rooted in the discovery of its unique properties that has allowed it
to reach exceptional precision and power (Bhawalkar, n.d.), making it immensely
valuable and unparalleled in its uses. In addition, the change in consumer
taste and preference with the evolving world dynamics has also created an
unprecedented growth in the demand for laser.
In this paper, this author will explore the historical rise
of laser, its current developments and the resultant implications of laser that
includes the risks involved in utilizing this technology. The discussion also
encompasses the future considerations in employing laser technology as a
solution to the problems faced by mankind or as a tool to enhance the quality
of life, where the paper will aim to deal with the management of risks and
fears highlighted and predict the potential areas of advancements in the uses
of laser that provides for the eventual sustainability of this technology.
1. Introduction
Laser has assumed a
ubiquitous role in modern civilization, dictating our present and shaping our
future with its vast applications in the many sectors that make up today’s
diverse society. Growing demands coupled with advancements in science and technology
has culminated in the extensive development of lasers since the invention of
its predecessor, maser, in the 1950s. Currently, there are more than 10,000
different types of lasers, each carrying a different promise in improving the
quality of life for mankind. In light of present trends that point towards the
popularity of laser as a solution to the many challenges we face and its
expansion into more industries than we thought possible, there is a need to
learn more about this technology. Moreover, the likelihood of wielding this
technology in the future is also highly probable as new uses of laser are being
constantly discovered and capitalized on with the cutting edge technology that
we now possess. Notably, the extraordinary properties exclusive to laser has
given it an advantage over other innovations and made it both a precise and
powerful weapon to have, with the increasing cost competitiveness adding
viability to its value (Clark, n.d.). As the true potential of laser has yet to
be maximized, it is apt to predict that this superior technology is here to
stay, making this research extremely relevant. Although applications of laser
are abound, what we have generated thus far is merely the tip of the iceberg
and mankind has yet to see the best and most of this intriguing technology.
However, owing to the innumerable types and uses of this versatile technology,
it is wise to narrow down on the main areas that laser has been applied to.
Hence, this author will be focusing her discussion on a few key areas to
highlight the pivotal role of lasers in leading significant improvements made
within these main sectors: medical, military and communications. The reason for
choosing different sectors is to cover a diverse range of industries in order
to better appreciate the prevalence of laser while the impetus behind the
specific selection of major promising sectors is to demonstrate the prominent
role that laser has played in leading to breakthroughs that have allowed the
aforementioned industries to explore new frontiers.
This paper aims to
explore the history of laser since its inception in the 20th
century, tracing its evolution from a mere concept to the actualization of this
innovation and finally, its rise in prominence and prevalence. Next, the paper
examines the current situation that we are in, highlighting the contemporary
developments in laser that have helped solve problems and even improved the
quality of life for mankind. It also illuminates the way laser technology has
revolutionized life on Earth, transforming the future of our health, our
national security and our interaction with others. The paper also deals with
the possible consequences and complications that can arise from the improper
use of laser. This leads to the discussion of future considerations to manage
these problems and address fears that man might bear towards this technology.
In addition, the paper will underline the future of laser and predict the
potential areas of growth that aims to evaluate the sustainability of this
technology, in hope to bring to light the relevance and value of laser in the
future. Essentially, will laser still be as prevalent and prominent in the
future as it is now?
2.
Historical Perspectives
The birth of laser dates back to approximately a
hundred years ago in 1917 when Albert Einstein conceptualized the process of
“Stimulated Emission”, a fundamental principle that is later found to be behind
the construction of the first laser. This theory proposes that the interaction
between high-energy atomic molecules and a lower energy electromagnetic wave
will lead to a transfer of energy between them that in turn, stimulates the
creation of a photon with the same energy and frequency as the subsequent
photons emitted. The resultant light is an intense and coherent beam, otherwise
known as laser light (“Stimulated emission”, n.d.). Prior to the introduction
of laser, the knowledge of stimulated emission based on Einstein’s predictions,
first motivated the invention of MASER (Microwave Amplification by the Stimulated
Emission of Radiation) in the early 1950s (Halliday & Resnick, 1986, as
cited in “What is a maser?”, n.d.). Maser is a device that is capable of
generating powerful beams of radiation at short wavelengths by producing
coherent electromagnetic waves through amplification from stimulated emission.
Pioneered by notable scientists like Charles Townes, the first maser, ammonia
maser, was created in 1954. Demonstrations of the first maser at the Columbia
University reflected its capability of producing around 10 nanowatts of power,
radiating at a wavelength of slightly more than 1 centimeter (Rose, 2010).
However, maser carried a limitation that crippled its progress. The wavelength
of the light produced through this device was restricted to the microwave region
of the electromagnetic spectrum, which meant that maser could only operate at
microwave frequencies (“This Month in Physics History: Einstein predicts
stimulated emission”, 2005). Moreover, masers required high magnetic fields and
difficult cooling schemes to work, reducing its feasibility (Palmer, 2012).
This drove the creation of laser that had shorter wavelengths and was able to
generate more energy than its predecessor. In 1960, Theodore H. Maiman
spearheaded the construction of the first laser, the ruby laser. It is termed
as such because the ruby laser is made up of a ruby crystal. The chromium atoms
forming the crystal give ruby its vibrant red colour and result in the light
emitted from the laser to be of a similarly distinct deep red colour. As shown
in Figure 1 below, the ruby laser contains a quartz flash tube, a cylindrical
rod made up of ruby crystals and two mirrors at each end, one completely
reflective and the other partially reflective. The flash tube is a
high-intensity lamp spiraled around the ruby rod, where high-voltage
electricity within the flash tube causes it to generate an intense burst of
light that excites the atoms in the ruby crystal such that some of these atoms
produce particles of light (photons) when they reach a high energy level.
Through the process of stimulated emission, photons from one atom stimulate the
emission of photons from other atoms and the light intensity is amplified. The
mirrors placed at either end of the ruby rod reflect the photons back and
forth, further stimulating the emission of photons and continuing the process
of amplification. Eventually, the beam of light that leaves through the
partially silvered
mirror at one end of the ruby rod is known as laser light (“The first ruby
laser”, n.d.).
Figure
1. Components of the first ruby laser
Reproduced
from The First Ruby Laser. (n.d.)
The initial signs of
laser’s growth to prominence can be traced back to early 1963 when Barron’s
magazine estimated that the annual sales for the commercial laser market was
likely to hit $1 million after lasers began appearing in the commercial market
in 1961. This number is later seen to grow extensively as industry analysts
predict that the global laser market will grow about 11 percent in 2010, with
total revenue soaring to $5.9 billion (“History of the laser”, n.d.). Looking
forward from historical perspectives, it is expected that the global market for
lasers will grow further, reaching $8.8 billion in 2014 (“Recovery and new
opportunities spur 9% growth in laser market”, n.d.). Although laser sales were
punctuated by recession especially during the global economic recession of
2008/2009, the laser market has managed to recover its losses and record a
steady upward growth by 2010. According to Overton, Anderson, Belforte and
Hausken (2011), although the worldwide revenue earned from the laser market dropped
by a shocking 23.5 percent from the $6.54 billion recorded in 2008, its
recovery has been faster and more extensive than the predicted growth rate of
11 percent by 2010. In fact, laser sales increased by a sharp 27.3 percent from
2009 to 2010, neutralizing the 27 percent downturn witnessed during the
recession and the demand for laser has been observed to be growing ever since.
3.
Current Situation
Since
its invention, laser has evolved substantially, with modifications made and new
variations introduced since the first working ruby laser paved the way for a
growing laser market. Lasers are now perceived to be invaluable tools across a
multitude of applications as a consequence of their extreme versatility, easily
becoming one of the most significant innovations developed in the 20th
century (“Lasers in our lives, 50 years of impact”, n.d.). The inception of
laser technology with the introduction of the first laser can be described as
“a solution looking for a problem” and this problem soon found grounds across a
diverse range of sectors, including medicine, military and communications.
Notably, a laser’s distinctive qualities such as its unique production of a narrow
and intense beam of light that is able to travel in a specific direction
without dispersing; has differentiated it from ordinary light and increased its
value to the emerging demands and growing needs of the modern society (Garwin
and Lincoln, 2003). As a result, laser has been successfully harnessed as an
answer to challenges in the aforementioned sectors. Quoting Garwin and Lincoln
(2003), “Today, lasers are everywhere: from research laboratories at the
cutting edge of quantum physics to medical clinics, supermarket checkouts and
the telephone network”. This is especially true as we enter a technological
age, where turning to advanced tools for help to solve problems or improve the
quality of life is becoming almost instinctive and this precisely explains the
current situation where laser is seen to be both prevalent and prominent.
Hence, this paper aims to examine the different types of laser used in the
present day as means to solving problems faced in the three key sectors or as a
revolutionary technology employed in these industries to improve the quality of
mankind. The implications of laser on the health and safety of mankind will
also be included in the discussion of the current situation within the laser
market.
(i)
Laser as it is today
In
this paper, I will explore some of the current developments in laser that have
been used to cater to the demands and needs of the identified industries in
order to provide a better insight into the present situation within the laser
market.
a)
Medicine
Laser
medicine refers to the use of a variety of laser types in the process of a
medical diagnosis, therapy or treatment (“Lasers in Medicine”, n.d.). Each laser operates within a very narrow wavelength
range and emits a strong beam of coherent light that is capable of focusing on
a very small point, enabling lasers to have a high power density aimed at a
specific area (Harris, 2011). These special properties have given lasers an
edge over sunlight or other light sources at targeting medical applications,
which explains both the use of lasers in many areas of medical diagnosis and
treatments (its prevalence), as well as the significant rise in the number of
medical procedures carried out (its prominence) using this superior technology
(“Advancements in Laser Technology Drives the Global Medical Laser Systems
Market, According to a New Report by Global Industry Analysts, Inc.”, 2013).
Advancements
in laser technology have generated a plethora of applications within the
medical field, where some of the current developments include the use of laser
in areas such as ophthalmology,
oncology, cardiology, dermatology, dentistry, cosmetic surgery, diagnostics, gynecology,
gastroenterology, and urology (“Advancements in Laser Technology Drives the
Global Medical Laser Systems Market, According to a New Report by Global
Industry Analysts, Inc.”, 2013). This report will serve to provide insights
into the use of medical lasers in some of these areas highlighted.
1. Ophthalmology
Ophthalmology is the branch of medicine that is
concerned with the study and treatment of disorders and diseases of the eye. Ophthalmology
currently utilizes an imaging technique named Optical Coherence Tomography
(OCT) that is able to give high-resolution, cross-sectional, and
three-dimensional images of biological tissue in real time by making use of the
coherent light emitted from a laser. This technology has allowed ophthalmologists
to see a cross section of the cornea to diagnose retinal disease and glaucoma,
demonstrating the importance of laser in medical applications. Beyond the use
of OCT to diagnose problems related to our eyes, there has been much enthusiasm
about its potential in other areas of medicine. According to Fujimoto, a
co-inventor of this technology from the Massachusetts Institute of Technology
(MIT), one of the major areas that is emerging for OCT is fiber optic imaging
of arteries, where the harnessing of OCT as an imaging tool for observing heart
vessels will create a breakthrough in the medical field as it gives
cardiologists the unprecedented ability to see what they are doing (Harris,
2011).
The application of laser in ophthalmology is not merely
limited to the diagnosis of possible complications in our eyes but also extends
to the treatment of these complications. Laser-Assisted In Situ Keratomileusis
(LASIK) is an example of how laser has been employed to treat refractive
errors, improve vision and reduce or eliminate the need for spectacles or
contact lenses. This procedure makes use of a highly specialized laser, the
excimer laser, to alter the shape of the cornea, which is the transparent front
covering of the eye that is responsible for the refraction of light and
accounts for approximately two-thirds of the eye’s total optical power (Randleman,
n.d.). LASIK involves the use of an instrument called a microkeratome to create
a thin and circular flap in the cornea. The surgeon then proceeds to pull back
the hinged flap to remove the underlying corneal tissue with the use of an
excimer laser that generates a cool ultraviolet light beam to precisely ablate
tissue from the cornea to reshape it. The flap is then repositioned and laid
back into place, covering the area where the corneal tissue was removed. When
the cornea is reshaped in the right way, it is able to better focus light into the
eye and onto the retina, providing clearer vision and correcting refractive
errors such as myopia and astigmatism (“LASIK technology to boost eye
refractive surgeries in Kenya”, 2013). LASIK has been proven to be safe and
effective for majority of the patients, with many advantages such as its
ability to accurately correct most levels of myopia (nearsightedness),
hyperopia (farsightedness) and astigmatism, with a fast procedure that usually
lasts only 5 to 10 minutes and is generally painless. Moreover, since a
computer guides the laser, the results are precise and accurate, with most
patients requiring only a single treatment to achieve the desired outcome
(Randleman, n.d.). As of 2010, over 20 million people worldwide have undergone
LASIK surgery, making it one of the most common surgeries performed today, a
phenomenon that would not have been possible without laser technology (“LASIK
& Laser Eye Surgery”, 2013). The extensive use of laser in medicine and
surgery is no wonder laser has grown to become a technology both prominent and
prevalent in the medical field as it is harnessed both as a solution to the
various health complications we have and as a tool to improve the quality of
life for mankind.
2. Oncology
Oncology is the branch of medicine that deals with
cancer through the study and treatment of tumours. Lasers play a major role in
the early detection of cancer. The infrared (IR) laser, for example, is
capitalized on for its potential in infrared spectroscopy, which deals with the
infrared region of the electromagnetic spectrum. This is light with longer
wavelength and lower frequency than visible light. IR lasers will thus be
useful since cancer and healthy tissue may have different transmissions within
the infrared range. Currently, researchers are exploring the application of IR
laser in measuring melanomas and detecting skin cancer, where early diagnosis
is vital to the survival rates of patients. The IR laser is tested in Israel
during its annual free public melanoma screenings and it was proven to have
enabled physicians to differentiate between benign marks and actual melanoma in
patients suspected to have skin cancer (Harris, 2011).
Apart from its uses in the diagnosis of cancer,
lasers are also increasingly used in the treatment of different types of
cancer. This is because lasers are less damaging to the human body compared to
X-ray therapies and surgeries. Lasers are highly effective in curing illnesses
related to gynecology, ear, nose, throat, tongue, palate and cheeks, being
curative in the early stages of cancer and valuable in reducing tumours to
facilitate surgical procedures during the later stages of cancer. Currently, a
new type of cancer treatment known as photodynamic therapy (POT) is introduced
into the study of oncology that combines laser with light-sensitive dye or
hematoporphyrin derivative (HPD). HPD comes from cow’s blood and is injected
into the body of patients such that the substance settles in the malignant
tissues. A red light from the argon pumped dye laser is then focused onto the
area and proceeds to activate HPD, where the energized substance will then
release a highly reactive chemical that destroys the cancer cells. Reports have
shown that POT is 80 to 90 percent successful in resulting in the total or
almost total regression of tumours, remaining effective even if other forms of
therapy are exhausted and have failed. This technique is highly selective for a
diseased tissue and leaves healthy cells relatively untouched, reducing the
risk of utilizing this laser technology. Indeed, the use of lasers to remove
cancerous growths or tumours in the body has heralded an era of knifeless and
bloodless surgery in some cases, illustrating the importance of laser in the
medical sector as a tool harnessed to provide solutions to the health problems
that mankind faces (“Laser and its applications”, n.d.).
b)
Military
Currently,
laser is also used for military purposes, where its applications in
establishing defense and security are far-reaching and covers land, water and
air protection. This exemplifies the prevalence and prominence of laser in the
modern context where advanced technology is consistently being put to use to
either address challenges or increase the quality of life. This paper will
examine some of the uses of laser to enhance water and air prowess for the
military to provide its people with greater safety and surveillance.
1. Water: Underwater laser
Lasers are currently used for underwater transmission
of signals. Previously, submarines have to depend on sonar to locate enemy
vessels and to steer clear of objects underwater, which has severe limitations
since marine animals like whales and dolphins can send false signals that leads
to the sonar system being inaccurate in alerting the navy. Moreover, the sonar
system cannot provide a well-defined picture since the sonar beam is scattered
and spread out underwater, with the salt in seawater further causing the sonar
beam to bend and create a wrong illusion that the target is appearing when it
is not in reality. One other key consequence of using sonar is that it exposes
the position of the craft to the enemy, hindering the navy’s ability to remain
concealed when conducting their operations. In light of these problems, a
superior technology needs to be introduced and this comes in the form of laser
technology. Lasers are currently employed for effective ranging (the process of
determining the distance between one position to another position) and
detection of underwater objects or potential enemy targets. This is achieved with
the use of a frequency doubled Nd:YAG laser, an argon ion gas laser or a Raman shifted xenon chloride laser. A
schematic diagram of an underwater ranging and viewing system is shown in
Figure 2 below. It consists of a laser transmitter, which sends high power
laser pulses of about 10-nanosecond duration to the target at the rate of 30 to
50 per second through a beam splitter. After going through a diffuser, laser
light that is reflected by the beam splitter is made to fall on the photodiode
in the ranging and display circuit to start the time interval counter. The
reflected light from the target is collected by telescopic optics after an
interference filter eliminates stray radiation. A range gating circuit helps to
avoid unwanted echoes. The reflected pulse from the target is intensified by
the image intensifier and the output is sent to the image orthicon, which generates
an image of the object. In this way, both the range and the image of the target
are obtained. With high power release of several megawatts, underwater ranging
is possible up to 500 meters in clear water. This allows the military to navigate underwater more effectively (“Laser and its
applications”, n.d.).
Figure 2. Schematic diagram of underwater
ranging
Reproduced from Laser and Its
Applications. (n.d.)
Other military uses of
laser include underwater communication between submarines, where lasers are
employed to build a guidance system with absolute privacy for torpedoes
(self-propelled underwater missiles) and other unmanned underwater vehicles so
that they are able to navigate without direct or continuous human control. Recent
underwater laser communication has been established via satellite, from
ground-to-satellite and then to underwater stations (“Laser and its applications”, n.d.).
1. Air: Air Reconnaissance
Lasers are also used as secretive illuminators for high
precision aerial reconnaissance especially in the night. Previously, this was
achieved using a camera equipped with magnetic flares or powerful strobe lights
but the power supplies were simply too cumbersome. Lasers, with their useful
properties of having a narrow and intense beam of light, are thus sought after
as an alternative to earlier technologies. A helium-neon laser or a gallium
arsenide semiconductor laser is employed to provide air reconnaissance. The
schematic diagram of the laser camera is shown in Figure 3. According to the
diagram, light from a laser beam travels downwards through a six-sided prism
scanner towards the surface of the Earth, where the prism will scan through a
selected angle that is right angle to the direction of the flight of the
aircraft. Another beam of light passes through a Pockels cell modulator and when
it emerges from the modulator, the beam strikes the prism scanner and is then reflected
and recorded on the film. The laser beams reflected from the target area are
picked up by a Schmidt lens, which projects the light onto a photodetector. The
video output of the photodetector corresponds to the reflectivity of the
observed terrain and thus, drives the modulator. The returned beam then
modulates the original beam. The images generated are similar to those captured
under daylight conditions. Hence, this allows the military to photograph the
movements of their enemy targets even at night under high secrecy during the
flight of the aircraft. Currently, this laser system has been tested and proven
to be a success by the United States Air Force Tactical Air Reconnaissance
Centre, demonstrating the importance of laser technology even as a tool to aid
in the operations of the military (“Laser and its
applications”, n.d.).
Figure 3. Schematic diagram of a laser
camera
Reproduced from Laser and Its
Applications. (n.d.)
a)
Communications
The
current use of laser as means to transmit signals and send data has
revolutionized the way we communicate, replacing conventional methods that make
use of radio frequencies. The finite nature of the radio spectrum coupled with
the insatiable appetite for these radio waves has made laser an even more useful
technology in a world that increasingly demands faster and higher quality
communication. The military is one major contributor to this phenomenon,
especially with the introduction of unmanned aerial vehicles that requires the
ability to transmit live, streaming videos to military bases around the globe.
Moreover, this demand is postulated to increase with the proliferation of
higher resolution sensors that feed on more bandwidth. In addition, overcrowded
radio airwaves are susceptible to interference or illegal operations by
opponents to jam signals and intercept messages. On the other hand, laser
communications do not make use of the radio spectrum, which eliminates the
problems and limitations of using radio waves (Magnuson, 2013). A particular
aspect of laser transmission that makes it preferable to the ordinary radio
waves is the strict secrecy enabled by the narrow beam width of laser light. A
high level of secrecy is preserved between two points because no unwanted
reception outside the narrow rays emitted from the laser is able to pass
through and hence, an interception-proof communication network can be brought
to fruition (“Laser and its applications”, n.d.). This is especially useful in
the area of communication for military purposes since adversaries have to first
detect the narrow laser beam and then place an object in front of the ray in
order to disrupt the transmission. Furthermore, to intercept the data sent, a
receiver has to be positioned in the path of the laser beam, all of which are
difficult to do especially without detection (Magnuson, 2013). Moreover, a laser communication system
is immune from jamming and from interference by spurious radio noise, which
makes it an even more effective technology in facilitating communication
(“Laser and its applications”, n.d.).
Laser
communication can also be harnessed for space purposes. While radio-based space
communications are used typically, current advancements in laser technology can
revolutionize the way we send and receive signals, video, images and other data
since lasers are able to transmit data at a speed 10 to 100 times more
efficiently than radio frequencies while consuming conspicuously lesser power.
In addition, the shorter wavelength of lasers ensures that energy is not
unnecessarily dispersed as the light travels through space. A conventional Ka-band
(A component of the K band within the microwave band under the electromagnetic
spectrum) signal from Mars, for example, is dispersed excessively such that the
diameter of the energy when Earth receives it is of a magnitude greater than
the Earth’s diameter. A signal sent by a laser however, disperses over a
smaller area (the distance across a small part of America) and thus, wastes
less energy. Moreover, shorter wavelengths allow for significantly more
bandwidth compared to radio frequencies, where radio waves have to fight over a
limited and finite bandwidth. Currently, invisible and near-infrared lasers are
tested for the purpose of sending data to and from the satellite and the NASA
team is working towards developing a stable, efficient and cost-effective
optical laser communication technology (“Technology Demonstration Missions:
Laser Communications Relay Demonstration (LCRD)”, 2013).
(ii)
Laser and its implications
While laser has brought
about a string of benefits for mankind, it would be over-ambitious to assume
that it is without its shortcomings. Laser technology has multiple risks
attached to it, and can potentially cause complications despite it being deemed
as a relatively safe instrument to wield (“Risks from lasers”, n.d.). This
paper will analyze some of the impacts of laser on health and safety to provide
a more holistic understanding of not merely the benefits but also the possible
dangers and consequences of utilizing this tool. This knowledge is especially
important in light of the growing prevalence and prominence of laser in an
advanced and technologically reliant society as the one we currently reside in,
as it ensures that we reduce the chances of having asymmetrical and imperfect
information of the technologies that we make use of.
1.
Impact
of laser on health (Risk of laser in surgery)
Lasers
used for the purpose of surgery can have negative impacts on our health. This
is because all medical procedures including laser treatments expose patients to
varying degrees of risk and complications. While we can minimize the extent of
the risks involved, it is nearly impossible to completely eliminate the dangers
attached to medical operations. Hence, it is prudent that patients are informed
about the potential hazards before undergoing laser surgery. Similarly, medical
practitioners should attain a good knowledge of the implications of laser and
its causes to better manage and prevent these complications from occurring
(“Risks from lasers”, n.d.). Hence, this paper will examine the risks involved
in laser surgery to demonstrate the impact of laser on our health.
a)
Risks of laser eye surgery
According to the Royal College of
Ophthalmologists, severe complications as a result of laser eye surgery are
rare with negative side effects arising in less than 5% of patients undergoing
this treatment and chances of extreme implications such as blindness occurring
being almost completely absent (“What are the risks of laser eye surgery?”,
n.d.). However, this does not nullify the existence of risks and complications
involved. Some of these risks include the possibility of impaired night vision
after the laser eye surgery, which makes it difficult for the patient to see
under dark conditions. As a result, glares, haloes or double visions may occur
that can cause sight to be uncomfortable for these affected patients. This is
because the surgery can reduce the patient’s vision under dim light even though
a positive visual result is recorded under standard testing conditions after
the laser eye surgery is completed (“LASIK eye surgery: Risks”, 2011).
Apart from that, corneal flap complications can
arise as a consequence of laser eye surgery. These problems surface in the
process of removing or folding back the flap during the surgery (“LASIK eye
surgery: Risks”, 2011). A slipped corneal flap, which is a flap that becomes
detached from the rest of the cornea, is a common complication that occurs
after the surgery. While the chances of corneal flap dislocations are reported
to be highest immediately after the surgery, late dislodging of the corneal
flap is not unusual and can occur 1 to 7 years after the surgery (“LASIK
complications”, n.d.). In-growing cells is another laser surgery risk that
occurs when trapped debris causes cells to grow underneath the corneal flap
(“What are the risks of laser eye surgery?”, n.d.). Epithelium, the outermost
corneal tissue layer, ends up growing abnormally under the flap (“LASIK eye
surgery: Risks”, 2011) in a symptom called epithelial in-growth (“LASIK
complications”, n.d.), which can develop into a sight-threatening complication
that leads to the patient having to risk the probability of visual impairment
(“Epithelial Ingrowth”, n.d.).
Laser eye surgery also hinders with tear
production and thus, patients might face with exceptionally dry eyes during the
post-surgery period (“LASIK eye surgery: Risks”, 2011). Dry eyes are
accompanied by stinging or burning sensations that are painful and can affect
the quality of vision, with the bad news being that this negative side effect
is among one of the most common risks of laser eye surgery (“What are the risks
of laser eye surgery?”, n.d.). Moreover,
in extreme cases, severely dry eyes can occur and cause permanent chronic pain
or even blindness especially when it is left untreated (“LASIK complications”,
n.d.). Thus, it is vital that patients get sufficient information about the
risks of using such a technology especially if they are prone to conditions
like dry eyes that can worsen after the surgery is conducted (“What are the
risks of laser eye surgery?”, n.d.).
b)
Risks of laser skin surgery
Aggressive advertising has culminated in a
century centered on the pursuit of beauty and youth. The advent of cosmetic
laser technology has fueled this obsession with smoother, fairer, younger and
more radiant skin. However, many are unaware of the resultant complications
that can arise as a result of such dermatologic laser surgery. My paper
explores some of these risks to bring to light the potential negative
implications of using laser.
One of the epidermal complications that can
arise as a result of dermatologic laser surgery is postoperative blistering,
which is the formation of blisters or vesiculation due to epidermal thermal damage.
This negative side effect can develop from all laser systems used in laser skin
surgery and is typically witnessed from the use of Q-switched laser irradiation
for tattoo removal. Some reasons for the development of this complication
include the use of too much laser fluence (a stream of laser particles) or the
unintentional absorption of laser energy due to the increased presence of an
epidermal chromophore (an atom or a group of atoms responsible for the colour
of a compound) such as melanin in a tan. (Brown, 2012).
One of the dermal complications that occur
following laser skin surgery is scarring. This is among one of the most feared
negative implications due to its long-lasting and near-permanent nature.
Scarring results from direct laser-induced thermal damage or from complications
such as postoperative infection that leads to excess damage to the collagen
comprising the dermis. Cutaneous laser resurfacing has the highest risk of
causing scarring due to the deliberate destruction of dermal tissue and the
increased risk of infection occurring in the de-epithelialised skin. Moreover,
since every individual’s skin has different levels of receptiveness towards
such laser treatments, it is difficult for a surgeon to predict the
implications of laser skin surgery and thus, the risk of such complications are
still existent despite being operated on by the best and most well-trained
surgeons (Brown, 2012).
2.
Impact
of laser on safety (Risk of laser on aviation safety)
Laser
light can be harnessed for multiple purposes across a diverse range of sectors
as described in the above section on the current uses of laser. In this segment,
however, the paper will explore a different side of laser light as it serves to
highlight the potential risks attached to utilizing laser technology, with the
focus placed on safety considerations in the area of aviation.
Lasers
are aimed at airspace for various reasons that differ from entertainment in the
form of laser pointers or outdoor shows, to research in fields like astronomy.
Lasers are even used to shine at aircrafts to warn pilots that they are
straying into unauthorized air spaces. For the purpose of this research paper,
I will narrow down on the risks associated with the use of lasers that affect
aviation safety. Laser light can be hazardous when it is directed at aircrafts.
In United States, it has been reported that the number of incidents of lasers
being directed at its aircraft has exceeded 2,800 since 2004, raising concerns
towards the misuse of lasers aimed into airspace as they create dangerous
flight conditions for pilots, endangering the lives of those on board the plane
(“Laser safety”, 2013). This happens when the sudden and unexpected burst of bright
visible light causes distraction to the pilot and result in them feeling
unsettled. Moreover, as the brightness of the light intensifies, it can
interfere with a pilot’s vision due to the glare from the laser light that
makes it arduous to see out the windscreen. A pilot’s night vision might be
shrouded and this can disrupt the smooth proceedings of a flight operation. Laser
light can even lead to temporary flash blindness for the pilot that
incapacitates a pilot’s ability to see clearly and stimulates the appearance of
afterimages that leaves temporary spots in the pilot’s vision. These negative
side effects can lead to severe consequences if the pilot is unable to recover
his sight on time as it jeopardizes the safety of the crew and passengers on
board the plane especially during critical phases such as takeoff, landing and
emergency maneuvers. While such cases are rare, the danger of lasers causing
eye damage is not entirely mitigated. High power laser light is capable of
leading to permanent eye injury. This injury varies in its severity depending
on the precision and intensity of the laser light shone on the aircraft. In
extreme cases, such eye damages as a result of the bright light emitted from a
laser can induce a state of complete and permanent loss of vision (“Lasers and
aviation safety”, 2013).
Bearing
in mind the implications stemming from the various applications of laser, it is
prudent that users of laser are aware of the risks involved so that they can
form more informed decisions before wielding this technology. This is
especially important since laser is becoming increasingly prevalent and
prominent as proven in this paper, which leads to the consequences being amplified
and the urgency to manage these risks and fears being elevated. Thus, this
leads to the need for the subsequent section on the future considerations of
laser technology.
4.
Future Considerations
This
section of the paper explores the future considerations pertaining to the use
of laser technology. It will examine how risks and fears perceived can be
better managed through the introduction of counteractive measures, and predict
the future of laser technology to assess the sustainability of laser as a
prevalent and prominent tool.
(i)
Management of risks and fears
In
light of the various risks brought about by the applications of laser as
discussed above, it is beneficial to introduce the possible measures that can
be taken to manage these risks so as to allay fears that some might bear
towards the use of this technology.
a) Management of fears towards the risks of
laser in surgery
Risks
and fears towards the use of laser in surgery can be managed by following a set
of guidelines. This includes a comprehensive understanding of the dangers
involved especially in the case of a laser eye surgery that serves the purpose
of correcting an individual’s vision, which is considered an optional surgery
since it does not pose a grave threat to the patient’s health and well being (“LASIK
eye surgery: How you prepare”, 2011). As addressed above, patients with dry
eyes and other eye conditions such as keratoconus (a cornea condition) or
health problems such as HIV or other immunodeficiency conditions should particularly
factor in the possibility of an increased risk when undergoing the treatment
and the chances of laser aggravating their existing problems in the case of dry
eyes (“LASIK eye surgery: Risks”, 2011). This similarly applies to laser skin
surgery since laser treatment might not be suitable for sensitive skin and
inflamed or broken skin. Thus, it is important to undergo laser operations only
after detailed consultations under a registered practitioner so that the
patient’s suitability is fully evaluated and advised before the commencement of
the treatment (“Laser treatment”, 2012).
Post-surgery
measures can also be undertaken to reduce the risk of complications arising and
speed up the healing process. For laser eye surgeries, risks of negative
implications can be lowered if patients regularly attend post-surgery
examinations that monitor the recovery of the operated eye and ensures the
optical health of the patient. Patients also need to follow through with
post-surgery care by adhering to the regimen of eye drops, protective eyewear
especially under glaring lights and other procedures recommended by the
physician to better manage the risks of negative side-effects occurring (“After
laser eye surgery – Post LASIK care”, n.d.).
b) Management of fears towards the risks of
laser on aviation safety
Similarly,
there is a range of measures that can be taken to reduce the potential risks of
laser on the safety of aviation. This includes enforcement, where police
officers are mobilized on aerial vehicles like helicopters to patrol and
identify culprits that are misusing laser to aim into airspace and disrupt the
smooth proceedings of aircrafts. Hazard reduction measures can also be employed
to manage the risks of laser accordingly. Examples of such methods include the
termination of laser beams on structures like buildings or trees during outdoor
laser shows for entertainment as mentioned in the section above. This would
prevent the laser beam from trespassing protected airspace and interfere with
aviation safety. Another hazard-reduction measure that aims to minimize risks
is through the development and compliance of policies for outdoor laser operations
like that of National Aeronautics and Space Administration’s (NASA) “Use Policy
for Outdoor Lasers” and American National Standards Institute (ANSI) standard
“Safe Use of Lasers Outdoors”. Regulatory measures such as the implementation
of bans that restrict the use or sale of lasers can aid in the management of
risk of laser light being shone inappropriately on aircrafts. Countries can
follow the footsteps of Australia who imposed legal regulations on the
purchase, storage and utilization of laser pointers in 2008. Pilots and crew
can also undergo training to receive knowledge on the procedures towards
quicker recovery in the event of laser illumination. Articles with the likes of
“Laser Illuminations: The Last Line of Defense – The Pilot!” have also been
published in aviation magazines to provide more information on the management
of risks associated with laser beams. Lastly, active hazard-reduction measures
can be considered when dealing with the negative implications of laser on
aviation safety. These measures introduce protective eyewear such as laser
safety goggles to shield pilot from the bright light emitted from a laser.
Advancements in technology have allowed for the creation of smart goggles that
are capable of detecting laser light and stimulate a blockage or dimming system
according to the wavelength and intensity of the laser beam. Glare shields that
work like windscreen filters can also be used to minimize any incoming laser
light. These methods can serve to reduce the consequences of laser incidents
and thus, effectively manage the risks of laser on aviation safety (“Lasers and
aviation safety”, 2013).
(ii)
Laser in the future
The advent of lasers
in the 1950s has allowed for Man’s dream of possessing this useful and powerful
technology to materialize and its development since then has seen laser being
incorporated within our daily lives, as an important and transformational tool
of both prevalence and prominence (Noticewala, 2011). From surgery and medical
diagnostics to laser equipments for warfare and defence, lasers are employed in
virtually every facet of our lives (“Laser Innovation: Why The Next 50 Years
Look Even Brighter”, n.d.). However, future developments of laser are still
unknown, with the continued sustainability of laser’s pervasiveness and
preeminence being an open question to many. Hence, this paper aims to study the
situation of laser in the future. Moving away from historical perspectives and
the current situation, this section serves to provide a shift in focus towards
the potential areas of growth in the market of laser, which has been forecasted
to carry great promise in all the identified industries that will be covered in
detail below. This is especially so as the laser’s capability is now improving
in leaps and bounds with the use of science and technology to manipulate the
almost infinite combinations of pulse durations, pulse shapes, wavelengths and
power levels of laser that will exponentially increase the potential
applications of laser (“Laser Innovation: Why The Next 50 Years Look Even
Brighter”, n.d.).
a)
Medicine
According
to researchers, laser technology will be harnessed to create new alternatives
to conventional biomedical practices. For instance, lasers are extremely
beneficial as tools to aid in medical diagnosis because their useful properties
allow for non-invasive probing of tissue (Noticewala, 2011). In the diagnosis
of cancer, a biopsy is typically needed to confirm the nature of the lump
detected so as to ascertain if the growth is cancerous. However, such
conventional methods are usually time-consuming and so, lasers are employed
instead to develop faster and better diagnostic techniques to identify
cancerous cells. A laser-based sensor is developed for future applications to
aid in tumour detection by making use of a transmitting fiber to transfer laser
light to a microscanner mirror positioned at the end of the endoscope, which
deflects the laser beam and illuminate the identified tissue. An
8-millimeter-diameter micro-electro-mechanical system (MEMS) microscope head is
fixed into the laser-based sensor, where it will serve to magnify tissue cells
measuring merely 10-20 micrometers that are too small to be seen by the human
eye. In this way, this laser-based sensor can be used for future cancer diagnosis,
potentially eliminating the need to undergo biopsy (“Lasers deliver a bright
future for diagnostics”, 2010). The recent creation of a handheld laser scanner
also carries great potential in improving the future medical scene as it aims
to enhance the efficiency of breast cancer diagnosis. The laser scanner
produces a spectral “fingerprint” of patients to evaluate if the breast tumours
developed need more intensive treatments. This device generates comprehensive
breakdowns of the amount of hemoglobin, water and fat content, tissue density
and oxygen consumption by the tumour to allow medical practitioners to attain
more precise information on the effects of chemotherapy on cancer cells, and
thus determine the necessary treatments more accurately. This is a function
exclusive to the use of laser that the traditional mammogram is unable to
replicate. Taking into consideration the gray areas in the contemporary use of
the mammogram for breast cancer detection, this new laser equipment aims to minimize
the flaws associated with present technologies to improve the quality of
diagnosis procedures. This laser scanning method, for example, can improve
detection of breast cancer in younger women whose breast tissue are denser and
are hence, less sensitive to the mechanisms of a mammogram. While the
innovation is still under evaluation, it has definitely brought hope to the
advancement of medical diagnosis that is pivotal as the first step to the
treatment of potential health problems faced by mankind in the future (“Lasers
deliver a bright future for diagnostics”, 2010).
Apart from the uses of laser in
medical diagnosis, lasers also carry the potential in serving as the future of
addiction therapy. Researchers are looking into harnessing laser light as
solutions to stamp out addictive behaviours. Addictions to drugs such as cocaine
are becoming one of the major health concerns especially in countries like
America, where approximately 1.2 million people are affected by cocaine
addictions and annual emergency room visits as a result of cocaine usage are as
high as 482,188. A cocaine addiction occurs when victims consume the drug
compulsively and end up losing the ability to function without it, resulting in
the constant abuse of this drug. It has been reported that approximately 80
percent of the people who attempt to kick off the habit end up experiencing a
relapse within a short duration of six months, demonstrating the
ineffectiveness of present therapies in getting rid of cocaine addiction. This
is where laser can be employed to curb the addiction, possibly in the future.
Experiments are currently being conducted to measure the impact that laser has
on the brain activity of lab rats that were addicted to cocaine. Since cocaine
has been found to cause low levels of activity in the prefrontal cortex,
clouding one’s ability for behavioural flexibility and decision-making, laser
light is aimed at this region of the brain to test its effectiveness in reducing
addictions. The results of these experiments reveal that laser can activate the
nerve cells in the prefrontal cortex, where this newfound ability is proven to greatly
reduce addictive behaviours, providing mankind with a breakthrough in the use
of lasers for future applications in the medical sector (Nordqvist, 2013).
b)
Military
The
prominence of laser in the future is not merely exemplified by the potential
applications of laser technology in the medical sector but is also proven by
its expected use to improve military prowess in years to come. In America, for
example, the navy is expected to deploy lasers in ships by the year 2014. This
will give its military powerful cutting-edge weaponry, as the ship-mounted
laser is believed to be able to decimate small boats in the water and unmanned
aerial vehicles with the infrared energy emitted. The effectiveness of this
laser equipment has been tested and an unmanned drone was seen to burst into
flames after the laser was aimed at it. The laser’s ability to ignite and burn
targets without the hassle of having to replace the magazine like that in
typical firearms can be very useful in future military applications especially
as America can now use this superior technology to attack the drones utilized
by Iran to surround and harass the Navy’s ships. These lasers have a hundred
percent success rate in exterminating targets and possess several additional
advantages such as a relatively low cost of operating it ($1 per laser shot)
and the flexibility of the laser to have non-threatening functions alongside
its lethal capacities, which enables it to be used as means to send warning
signals to other vessels alongside its main purpose. Laser weapons are
described as the future of national defence and warfare, and similar laser
weapons are constantly being developed such as the FEL (free electron laser)
that is tested to be capable of burning and destroying feet of raw steel, with
a power range that is adjustable according to weather conditions. This provides
the military with an even more flexible weapon. While these laser-based
innovations are not released in the market yet, it is safe to conclude that
laser is here to stay (Fishel, 2013).
5.
Conclusion
In conclusion, this
paper serves to demonstrate the progress of laser technology from its initial
inception as a mere concept to its current state of prevalence and prominence.
The birth of the first ruby laser in 1960 has snowballed into the multiple
applications of laser across different industries such as medicine and surgery,
military and communications. Present day uses of laser include laser in
oncology, lasers for air reconnaissance and lasers to improve the efficiency
and speed of communication, all of which have served to revolutionize the way
we live as lasers offer viable and valuable solutions to the challenges we face
in our daily chores and have been employed to improve the quality of life for
mankind. Nevertheless, it is apt to recognize the limitations of using this
technology. Laser carries risks that can endanger our health and safety, which
would thus require counteractive measures to manage these negative implications
and minimize the adverse impacts of laser. With the availability of a diverse
range of methods to manage these risks, the future of laser technology is
enhanced especially as new and more cutting-edge lasers are increasingly being
materialized with advancements in science and technology that has ensured the
sustainability of laser’s prevalence and prominence even in the future.
6.
References
Overton,
G., & Anderson, S.G., & Belforte, D.A., & Hausken, T., (2011,
January 1). Annual Review And Forecast: Skies may be clearing, but fog still
lingers. Retrieved from http://www.laserfocusworld.com/articles/print/volume-47/issue-1/features/annual-review-and-forecast-skies-may-be-clearing-but-fog-still-lingers.html
