LASERS 12

Laser TechnologyMert Avcer

Control Engineering Faculty of Electrical and Electronics

040100662

Volkan Fenerciolu

Electronics and Communication Engineering - Faculty of Electrical and Electronics

040100472

Kamil Ozan Okuyucu

Electronics and Communication Engineering - Faculty of Electrical and Electronics

040120701

English 201

Suzan Arman

December 26, 2012Laser Technology

Thesis: It is generally agreed today that there are three main categories of using laser technology such as in defence, in medicine and science, and in industry.

I. Defence

A. Weapons

1. Airborne offensive laser system (Duffner, 2009, p. 203)

2. Range finder (Ready, 1997, p.256)

B. War tactics

1. Tactic truck (Gayle & Skillings, n.d.)

2. Chemical and Biological Threat (McAulay, 2011)II. Medicine and science

A. Medical applications of LASERs

1. Treatment of refractive errors (Refractive Errors, n.d., para.1)

(Sakimoto, Rosenblatt & Azar, 2006, p. 1444)

2. Treatment of dental problems (Walsh, 2003, p. 149)

3. Treatment of dermatologic problems (Shukla, 2012, para.3) (Elizabeth, Jason & Tina, 2003, p. 19)

B. Scientific applications of LASERs ( Bucksbaum et al, 2002, p. 9)

1. Astronomy (Smith et al., n.d. , para.1)

(Astronomical Society of Australia, 2008, Introduction, para.1)

2. Nuclear science (n.d., p.47)

(Pukhov and Meyer-ter-Vehn, 2002, p.1)

III. Industry

A. Industrial laser types

1. CO2 lasers (Thyagarajan, Ghatak, 2010, pp. 286, 287)

(Industrial laser types, n. d., para. 1)

2. Nd:YAG lasers (Thyagarajan, Ghatak, 2010, pp. 82, 280, 281, 282)

B. Using areas in the industry

1. Marking (Fermann, Galvanauskas & Sucha, 2003, p. 359)

2. Manufacturing (Fermann, et al., 2003, pp. 105, 327)

(Thyagarajan, Ghatak, 2010, pp. 487, 488)

3. Drilling (Thyagarajan, Ghatak, 2010, pp. 475, 476)

(Hecht, 2008, pp. 379, 380)

4. Cutting (Thyagarajan, Ghatak, 2010, pp. 476, 477)

(Hecht, 2008, pp. 384, 385)

Technology is a conception which develops and spreads with the innovation in the modern world. People have to reach that development if they cannot block it. One of the significant developments is laser technology at the beginning of the twentieth century. In the basic definition, laser means Light Amplification by Stimulated Emission of Radiation. Albert Einstein laid the base of laser technology when he explained the stimulated emission in 1917 (History of Lasers, n.d., para.2). These developments of technology need more sensitive, faster and stronger beams. Nowadays, laser technology provides these features. Theodore Maiman used laser in 1960 at Hughes Research Laboratories firstly. After that these applications provided multi-billion dollars industry (2008, p.7). Today, the applications of laser technology are starting to show in many fields. It is generally agreed today that there are three main categories of using laser technology such as in defence, in medicine and science, and in industry.

The first significant use of laser technology is in defence. To begin with, in defence and for safety weapons are very important. By the early 1990s, the air force, and a number of independent contractors had been actively occupied in adaptive optics research for two decades. During that time, there were many effective technical achievements in this comparatively new area of science. The Mobile Tactical High Energy Laser project funded a chemical laser weapon system assessment and hardware design and risk reduction activities supporting design. Gayle and Skillings emphasized that using lasers to shoot down missiles has long been one of the military's objectives, but implementing the technology has proven easier (n.d).. The U.S air force weapon system sustainment enterprise is extremely large in terms of scope and workforce. For example, airborne offensive laser system has made great strides in weapons. Duffner stated that the Missile Defence Agency ( MDA ) has established Airborne Laser as the primary boost phase defence element. Researchers, engineers and job contractors have developed ABL offensive system to fire high-power lasers at the speed of light from an aircraft over a range of several hundred miles to intercept and destroy ballistic missiles in their boost phase (p. 206). In view of this information, it can be claimed that airborne laser offensive system provides powerful weapons in the military. In addition, range finder provides stronger military defence. For example, the U.S Military has high distance measurement and dimensional control system. Ready asserted that pulsed laser range finders perform on the principle of emitting a very short pulse of laser light and measuring the transit time for the pulse to reach a perceivable target and for the reflected pulse to return to a receiver located near the laser. The narrowly collimated laser beam makes it possible to measure the range of specific targets and to receive a return free from ground clutter or interference from other objects near the target (1997, p. 274). From the examples given above, it is clear that range finder technology is important in terms of weapons in defence excessively. All in all, it can safely be said that developments in laser technology has made great contributions in the field of defence.Apart from the weapon, takes a very important place in the field of defense tactics of war. For example tactical truck has been developed on this issue between the most developed of the last battle tactics. The HEL TD vehicle is a 500-horsepower truck supporting a laser that can blast missiles out of the sky at the speed of light. As it is indicated in the article The Army's Eight-Wheeled Laser Truck that Zaps Enemy Missiles it is a heavy-duty, eight-wheeled, 500-horsepower, all-terrain truck that comes packing a 10-kilowatt solid-state laser system projected to explosion missiles out of the sky. Boeing first revealed the HEL TD in June 2011, but lately added new components to make it more powerful. Tactical truck developed on this issue between the most developed of the last battle tactics (n.d). In view of this information it can be claimed that prepared by laser technology that tactic truck takes a very important as a place of tactic war.In addition to these, chemical and biological threat plays a very significant role in war tactics. Lidar has been developing chemical and biological weapons to war tactics. Aluay asserted that Lidar means for light detection and ranging ( 3D image scanning ) and refers to systems in that a beam of laser light shines into the atmosphere and is scattered or reected from an object or from a cloud (2011, p.252) . As Aluay stated light wavelengths are low enough to sympathize with chemical and biological elements in the air, so the back scatter from an aerosol cloud may be examined for the existence of chemical and biological weapons. Lidar is improving fast to become one of the more considerable technologies for military implementations. However, Lidar, which manages at light frequencies, is look like concept to radar ( radio detection and ranging ) that manages at radio frequencies or microwaves. Furthermore 3D image scanning abilities, has an important additional ability in proportion to radar: it can specify chemicals. The shorter light wavelengths that range from infrared through distinguishable to ultraviolet can match the size of chemical or biological molecules and particles in an aerosol.(2011, p.252) All these examples prove that chemical and biological threat is major role in war tactics. It is clear that the laser technology very important factor in defence.

Another significant usage area of laser is medicine and science. To start with, lasers play a vital role in medical applications. For example; the lasers can be used as a treatment of refractive errors. Definition of refractive error is that seeing unclear image because of the deformity in shape of the cornea (n.d., para.1). Day by day, there is an increase in the laser treatment of eye defects. Especially, excimer lasers have revolutionized the field of laser eye surgery and over the decades have greatly increased the safety, effectuality of corneal refractive surgery. According to Sakimoto, Rosenblatt and Azar, even though phakic and adaptable intraocular lenses have a major share in the treatment of eye defects, the excimer laser will be used as a first treatment (2006, p. 1444). Obviously, this example shows that laser technology can be prefer instead of old method. In addition, treatment of dental problems is another area of using laser technology in medicine. When laser used for dental methods, the laser deals as a cutting device or a vaporizer of tissue that it comes in contact with. Therefore lasers provide great benefits to patients and doctors such as; less toothache , safety and faster than other treatments. Walsh states that there is no more tooth decay and tooth holes under favour of laser systems also this system has no effect on thermal and it doesn't put out to teeth and patient's comfort (2003, p. 149). Because of this advantages using laser surgery is spreading around the world. Dental lasers have only been used for soft tissue operations and teeth whitening until recently. However, with the development in technology and scientific revelation, their use has been widened to perform a wide range of dental procedures on both soft and hard tissues more comfortably. Moreover, another application of using laser is dermatology. According to Shukla when a laser beam is effected at the skin, it cleans natural pigments like melanin and hemoglobin. It is also absorbed by pigments introduced by means of tattooing (2012, para.3) Elizabeth, Jason and Tina state that lasers have made significant improvements and variations in dermatology thanks to secured treatments for skin disorders. Many dermatologic problems like inborned pigments, harmless lesions, removing tattoos, unwanted facial or body hair and rhytides can be cured (2003, p. 19). As this example shows, lasers will lead to a reduction in skin problems. As a result, it is obvious from the above that medical applications of lasers use treatment of refractive errors, dental problems and dermatologic problems, which will be the determining factor the medicine.

In addition to medical applications, another important usage field of lasers is science. Rapid developments in laser technology have led to the scientific advances from higher and higher intensity light beams for two decades. Using laser technology will be a modern mode of scientific applications with much greater facilities as lasers have opened new fields of studies in science (Bucksbaum et al, 2002, p. 9). To start with, lasers play a vital role in astronomical applications. Lasers are being used for practical astronomical applications by scientists and laser enthusiasts alike commonly. Especially, green lasers are the correct choice and perfect instruments As research by the Astronomical Society of Australia (ASA) indicates the usage of typical green lasers in astronomy has many advantages such as; providing more than 5 miliwatts in power, better sensivity of the eye to green instead of red more visibility thanks to being separated by air molecules and dust particles and safety (2008, Introduction, para.1). Besides making laboratory experiments in very high temperatures is easier than other methods. Bucksbaum et al reported that the following experiments can be done using the laser: hydrodynamic studies of shocks generated by the short laser pulse, studies relevant to the study of supernovae dynamics and the structure of the interstellar medium. Even more exotic astrophysical applications include the production of relativistic, matter-anti-matter plasmas with an ultrahigh intense focus (2002, p.11). These experiments will help to comment on astrophysical events. Considering all the information above, it can be said that lasers play a vital role for amateur and professional astronomers. In addition, nuclear science is another usage area of scientific applications of lasers. Using extremely high temperatures is required to achieve nuclear experiments. Lasers can be used during this process. As mentioned in the article Laser and Its Applications (n.d., p.47), thermonuclear fusion be in need of a temperature above one million centigrade to implement atomic fission. Today, this event is obtained by the use of laser. Lasers can be used to accelerate particles in nuclear physics. Pukhov and Meyer-ter-Vehn explained that the acceleration of electrons and ions needs huge electric fields which can be obtained by using propogation of laser pulses using LWFA (Laser Wakefield Acceleration) (2002, p.1). Obviously, proceeding of high power lasers and laser fusion research is useful for new applications in nuclear science. Considering the information above, it can be said that the lasers is used in astronomical and nuclear scientific applications commonly.

Finally, lasers are used in industry. There are different kinds of industry of lasers. In the structural fabrication, lasers are very effective in different ways. Different industrial fields need different types of lasers. Because sometimes lasers which are not coherent with the product can damage manufacturing. So, the lasers are separated according to their features. The industrial lasers have two basic types of lasers over constructive manufacturing. These types are CO2 and Nd: YAG lasers. To begin with, the CO2 lasers can be applied to the laser industry. According to Thyagarajan, Ghatak, the lasers are taken in hand over use of several electronic states of atom or ion conversions (2010, p. 286). The CO2 lasers are used in several fields of the structural industry. That type of laser is effective in marking plastic materials, paper, wood, leather, etc. At the same time, high power CO2 lasers are largely preferred in the automotive structural members, like gears and transmission members (Industrial Laser Types, n. d., para. 1). As it is stated by Thyagarajan, Ghatak, the CO2 laser has an extremely high efficiency of 30%. The CO2 lasers use the vibration areas of the carbon dioxide molecules. Because of the vibration of the molecules, they have energy. Every molecule can not have the same energy. So atomic quantum efficiency (45%) causes the laser transitions. After that time, large amount of the input power can be changed as useful laser power. Output powers between several watts and kilowatts can be procured from CO2 lasers. CO2 lasers which have high power are used in processes in materials welding, drilling, cutting, etc. Because they have very high output power (2010, p. 287). According to Thyagarajan, Ghatak, the Nd: YAG laser is an important solid-state laser system. In the laser emission, neodymium ion energy levels occur. These ions in the YAG make up some advantages (2010, p. 280). According to Thyagarajan, Ghatak YAG is a crystalline component. The Nd: YAG laser is a fourth level laser. The Nd:YAG lasers emission is about 01.06m. Thanks to the feature of being obtainable of high-power compact and impressive semiconductor lasers, using laser diodes, it is possible to pump Nd ions to the upper level. It causes very compact diode which is Nd-based lasers. Diode laser pumping is simpler and produces less heat than lamp pumping. That condition enables to increase efficiency. Because the laser diode output is diffrent from normal lamp. It is narrow band. Nd: YAG lasers can be used in resistor trimming, scribing, micromachining operations as well as welding, hole drilling, etc. In a homogenous transition, every atom has certain lineshapes which have the same frequency. In this way, every atom is affected with the same oscillting mode and this condition increases the pumping power, it can not affect other frequencies. Thus the oscillation becomes unique (2010, pp. 82, 281, 282). All things considered, one cannot deny the fact that CO2 and Nd: YAG lasers are indispensible components of the industry with their differnt features.

Lasers are tools which can be used in every field of industry. One of the usage areas is marking. Recently, the laser is used like an effective and useful tool in numerous industrial fields as industrial marking. According to Fermann, Galvanauskas & Sucha, special lasers are used for marking according to their features especially, Nd:YAG lasers are more common in marking field of the industry (2003, p. 359). Today, industrial lasers are inevitable for the industry. People who want to use or buy something, choose the inerrant products. If the industry should respond to needs of purchasers, manufacturers should make their products inerrant. It is possible with the lasers. Lasers are more effective and successful than traditional marking techniques. The other area is manufacturing. There can be some instabilities because of the type of the material, during manufacturing process. But lasers can decrease the error rate with their inerrant form. Fermann, et al. stated that industry is divided into two application fields as manufacturing and process control. So this condition makes lasers special (2003, pp. 105, 327). For instance, integrated circuit manufacturing industries using inferometer for control wafer steppers use the lasers for manufacturing (Thyagarajan, Ghatak, 2010, pp. 487, 488). In addition, lasers are common in the automotive industry area. Automotive industry is about the device manufacturing. In the automotive industry, manufacturing and process control are a must. So, lasers are inevitable for that industry. Drilling of holes in numerous substances is another noteworthy process of the laser. According to Thyagarajan, Ghatak, easily, a laser can drill holes as small as 10 m through the materials which are hard (2010, pp. 475, 476). According to Hecht, normally, drilling something which is very hard like diamond with the traditional is very difficult because of their form. But it is easier and faster with the lasers. Other examples are drilling baby-bottle nipples, rubber, etc. (2008, pp. 379, 380). In addition, lasers are found in the process of cutting materials. According to Thyagarajan, Ghatak, the CO2 lasers which are the most prevalent lasers are used in cutting processes because of their high output power (2010, pp. 476, 477). For the laser cutting, assistances to the laser are jet of air, oxygen, dry nitrogen. Cutting is the over-level of the hole drilling. Because, cutting is the combinations of the drilled holes (Hecht, 2008, pp. 384, 385). In view of all this information, industry is developing day by day with the innovation in the manufacturing processes and the biggest innovation is laser. Because the lasers provide inerrant structure in the materials. That inerrant structure responds well to purchasers. So, lasers with their types are tipping points in the industry.

To sum up, laser has big effects on medicine, defence and industry. In medicine, lasers provide new cure facilitations to people, because doctors cannot make operations which are tiny or as small as the nano degree with their traditional tools. In that time, they are abandoned to lasers. Technology is developing day by day and countries need to defend themselves against other countries. Especially, old world wars have big effects on this armament race. Lasers are the new generation armament tool. In addition, today purchasers want to buy or use inerrant products. Lasers responds well to peoples expectations. People want to live a healthy life and search for cures, they want to protect themselves against harmful actions and purchase inerrant products. Lasers respond well to all these matters. In the future, lasers will be the indispensable tools with the development of nanotechnology and the innovation in the technology. So people should discover the new areas for the lasers and use it in the all fields of technology.

References

Astronomical Society of Australia (ASA). (2008). The use of laser pointers in astronomy. Retrieved from Swinburne University of Technology website:

http://astronomy.swin.edu.au/~smaddiso/download/factsheet_22.pdfBucksbaum, P. et al. (2002). The science and applications of ultrafast, ultraintense lasers (SAULL)

Duffner, R.W. (2009). Adaptive optics revolution a history 9 airborne laser. University of New Mexico PressElizabeth, L., Jason, R. L., & Tina, S. A. (2003). Lasers in dermatology: four decades of progress. Doi: 10.1067/mjd.2003.582

Fermann, M. E., Galvanouskas, A. & Sucha, G. (2003). Ultrafast lasers: Technology and applications. New York: Marcel Dekker.Gayle, D., & Skilling, J. (2010). Mobile tactical high energy laser. Retrieved from

http://www.globalsecurity.org/space/systems/mthel.htm

Hecht, J. (2008). Understanding lasers (3rd ed.). New Jersey: IEEE Press.Industrial lasers. (n. d.). Retrieved from http://www.laserdeposition.net

Laser and its applications. (n.d.). Retrieved from http://drdo.gov.in/drdo/data/Laser%20and%20its%20Applications.pdf

McAulay, D.A.(2011). Military laser technology for defense: technology for revolutionizing 21st century warfare.WileyPukhov, A. and Meyer-ter-Vehn, J. ( 2002). Laser Wake Field Acceleration (LWFA). Retrieved from http://www.mpq.mpg.de/lpg/research/LWFA/LWFA.html

Ready, J. F. (1997). Industrial applications of lasers. San Diego Academic Press.Refractive errors. (n.d.). Retrieved from University of Michigan Kellogg Eye Center website:

http://www.kellogg.umich.edu/patientcare/conditions/refractive.errors.htmlSakimoto, T., Rosenblatt, M. I. & Azar, D. (2006). Laser eye surgery for refractive errors. Doi: 10.1016/S0140-6736(06)68275-5

Shukla, Dr. P. (2012). Cosmetic laser surgery. Retrieved from http://www.whereincity.com/medical/topic/plastic-surgery/articles/1256.htmThyagarajan K., Ghatak A. (2010). Lasers: Fundamentals and applications (2nd ed.). London: Springer New York Dordrecht Heidelberg.Walsh, L. J. (2003). The current status of laser applications in dentistry. Doi:

10.1111/j.1834-7819.2003.tb00025.x