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Trends of Laser Research
Researched,
compiled and written by World Lasers, Inc. © 2007
An in-depth research study was conducted by H. Golnabi and
M.H. Mahdieh in November 2004 at the Institute of Water and Energy, Sharif
University of Technology, Tehran, and Physics Department, Iran University of
Science and Technology, Tehran, Iran to analyze the trend of laser research
developments at global level. This article summarizes their findings as
published in this research paper.
The early developments of the laser research started from
the USA and Soviet Union in 1958. By 1960 about five different types of lasers
were introduced to the scientific community and the acronym ‘Lasers’ was
accepted as a global name for this quantum generator machine. Since then
scientists from some other countries contributed to the development of this
revolutionary field. During the past fourteen years from 1990 to 2003,
considerable efforts have been made in the development of new laser systems and
related equipment both in terms of science advancements, technological
breakthroughs, and also field applications.
The introduction of laser and related devices has
revolutionized the high technology and made a great deal of contribution to both
basic and applied research in different areas. Although the present laser
systems have not fulfilled all the preliminary expectations, important
advancements have been made by the advent of sophisticated laser systems in
optical communications, medicine industry and other fields of interest. Most
developed countries have made huge investments in their laser research programs
and as a result have found many interesting results.
In this article an up-to-date progress of the
international laser research and development from 1990 up to 2003 is given. In
their research the authors of this paper used ‘Science Finder Scholar Search
Engine’, which indexes more than 4000 journals, in different languages, and
represents most significant published materials in laser science and
engineering. The goal here was to understand the degree of the laser research
success in different countries in terms of resulting publications. The share of
top nations in laser publications in terms of their gross domestic product is
also presented.
It is noted that the four countries including the
USA, Japan, Germany and China have a laser publications contribution of 58.9% of
a total of nearly 3,50,000 papers published during the period of study
(1990-2003), while the rest of the world including 189 countries contribute
41.1%. However, counting patents registered, which is a more important factor,
these four countries contribute 90.1% against 9.9% by the remaining nations.
While USA is the biggest papers publisher it is Japan who has the lead in the
‘accepted’ patents category. This is not surprising, as, in Japan, out of
1000 employed personnel 9.59 persons are hired as researchers, defined as
professionals engaged in the conception or creation of new knowledge, products,
procedures, methods and systems and also in the management of the projects
concerned. US are next with 8.39 while UK is least among the key nations in the
full-time employed researchers.
USA has the highest percentage of citations, 62.76%,
United Kingdom, 12.78%, Germany, 10.4%, Japan, 6.9%, France, 6.85%, China, 0.99%
and South Korea, 0.78%. Only 31 of the world’s 193 countries produce 98.5% of
the world’s most cited papers.
The authors try to make a correlation between the
economic spending and the laser developments in terms of resulting publications.
The goal was to find a good correlation between the inputs and the outputs for
different nations and learn a lesson for performing outstanding laser research.
The second point was the new concepts and ideas, which might be essential for
the development of the new nanostructured lasers suitable for future
nanotechnology applications.
From the explored search under the topic ‘Lasers’
the total number of publications for the period of 1990–2003 is 351,824
publications. For the same period the number of the accepted patents is 48,448
items. This study shows that English is accepted as an international language
(78.37%). However, on the filed patents the number of the published patents in
Japanese is about 64% while in English it is 26%, which shows the degree of
laser progress in Japan.
In the material processing by laser systems the major
applications are welding, drilling, hardening, and laser engraving. From a total
of 5954 publications for this area, welding research has devoted 4993 papers
with the number of 1288 patents. Laser drilling is another potential application
for industrial laser systems, which devoted a number of
1237 papers and 381 patents.
Looking at the past trends indicates that there is
greater tendency towards smaller and more efficient semiconductor lasers. Higher
power and efficiency have been the ultimate goal for most applications. There
are many studies about X-and gamma-ray lasers that are able to operate in the
short wavelength region of the spectrum
The new search is accomplished under the term of different
laser types such as ‘CO2 laser’ Semiconductor laser, Excimer, Ion, Chemical,
Nd: YAG, X-ray, and Nitrogen laser In the area of semiconductor lasers a great
deal of attention has been paid to the quantum well and quantum dot lasers.
There has been a great interest in the solid state physics for the development
of new soliton and polariton lasers. Nitrogen laser shows the lowest number of
publication, which is around 5213 published papers and 524 filed patents.
The major applications are grouped into scientific
and industrial applications. However, the military application is a true
combination of both categories in a more advanced fashion. The laser research
and development is divided into different categories such as developments and
applications in material science, chemistry, medicine and biology, physics and
engineering, and finally industry and military. 1558 published papers including
163 patents. In a search under the term ‘‘future application of lasers’
there are 705 papers and only one patent for that period of time. One promising
area of application of lasers would be in the photochemistry and photobiology
for structure analysis.
The authors have noted the need for more studies in
quantum physics and quantum electronics of the lasers in order to deal with
quantum effects such as quantum tunneling, noise and defects in the molecular
devices. There is a need to learn how to produce small features for
semiconductor lasers and how to manipulate small size nanostructures compatible
with the advancing nanotechnology. Also, there is a need to know how to handle
mass production of electric and electronic components of lasers suitable for the
integrated circuits and integrated optics at lower costs. Furthermore, there is
a need to make the fabrication process more cost effective. At present,
commercial diode lasers are available in the range of $10–100. The cost of a
laser diode still is 10 times that of the LED light source. The major problems
and hurdles in the laser area are mainly experimental. Also we still need
further developments in technical areas.
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