DOCSLIB.ORG

United States Patent (19) 11) 4,053,845 Gould 45) Oct

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
United States Patent (19) 11) 4,053,845 Gould 45) Oct United States Patent (19) 11) 4,053,845 Gould 45) Oct. 11, 1977 (54) OPTICALLY PUMPED LASER AMPLIFIERS Levgyel, "Evolution of Masers and Lasers', Amer. Jour. of Physics, vol. 34, No. 10, 10/66, pp. 903-913. 76 Inventor: Gordon Gould, 329 E. 82 St., New York, N.Y. 10028 Primary Examiner-Nelson Moskowitz Attorney, Agent, or Firm-Lerner, David, Littenberg & (21) Appl. No.: 498,065 Samuel 22 Filed: Aug. 16, 1974 (57) ABSTRACT Optically pumped laser amplifiers are disclosed. One Related U.S. Application Data type of such amplifier utilizes an excitable medium, the 60 Continuation of Ser. No. 644,035, March 6, 1967, atoms, ions or molecules of said medium having well abandoned, and Ser. No. 804,540, April 6, 1959, defined energy states including a lowest state, a lower abandoned, said Ser. No. 644,035, is a division of Ser. state above said lowest state, and a higher state above No. 804,540, , and a continuation-in-part of Ser. No. said lower state, and a bright pumping light source 804,539, April 6, 1959. composed of a radiative substance different from such medium which radiative substance emits energy in a 51) Int. Cl? ......................... H01S 3/091; H01S 3/22 spectral range which can be absorbed by such medium, 52 U.S. C. ............................... 330/4.3; 331/94.5 G; and wherein the major portion of the energy absorbed 331/94.5 P by such medium causes transitions of the atoms, ions, or 58) Field of Search ................... 330/4.3; 331/94.5 G, molecules thereof to populate the higher state. Another 331/94.5 P, 94.5 D; 324/15F type of such amplifier utilizes a medium of atoms, ions, (56) References Cited or molecules, some of which have broad bands of en ergy levels corresponding to a broadband of absorption U.S. PATENT DOCUMENTS transitions and energy levels corresponding to at least 2,929,922 3/1960 Schawlow et al. ................... 330/4.3 one fluorescent emission transition, the upper energy levels of said broad bands being above the upper level FOREIGN PATENT DOCUMENTS of said fluorescent emission transition, and wherein 148,441 1959 U.S.S.R. ................................ 330/4.3 some of the upper energy levels above the upper level 123,209 1959 U.S.S.R. ................................ 330/4.3 of said fluorescent emission transition are rapidly quenched via non-radiating transitions to the upper OTHER PUBLICATIONS level of said fluorescent emission transition. In a pre Fabrickart, "Electronic and Ionic Devices (Transla ferred embodiment of the latter amplifier, the lower tion)', Trudy, vol. 41, 1940, pp. 236-296. energy level corresponding to the fluorescent emission Butaeva et al., "Investigations in Experimental and transition is relaxed by non-radiating transitions. Theoretical Physics', 1959, pp. 62-70, Studies in Exper imental and Theoretical Physics. 12 Claims, 7 Drawing Figures A SAV/Aa - 1 -426 AAA/DV ad7477//6 A/ASA/D AAS2/4/7 M7/66Oa A/6A/7 a.MWA/A/A6 Al 72A U.S. Patent Oct. 11, 1977 Sheet 1 of 6 4,053,845 7-33 OV&A “Y or W SAWS/772A2 R.l. as2 s WOA6%/M/6 %24.(Wa 6.4S) : /2 24 NO c ax/7 awaz 1 AX6/7/W6 Af A/6A/7 SOC/ECA 22 aAAAAC76 e.7. M40 /awzae INVENTOR. (70,620// 6702/2 BY ... ." ... ." U.S. Patent Oct. 11, 1977 Sheet 2 of 6 4,053,845 Tise. - 5 7-46? of Hg 54.612 V. t2?20a 6 4.677 / Q 6. 0.63 4/05 sec/ I.O 6 5 0,00/As b al 4. S. 0.00/2 too, R 4. S.V) S 3 0.0043 l & s S. o 2xtes sec . S 2 S S S N \& Ya VS SQ O *P3s Fs 22. 27 INVENTOR. GoAedow Gould BY U.S. Patent Oct. 11, 1977 Sheet 5 of 6 4,053,845 A "r ELAC Teow/c OWLY LOWEST Gaol/WA S747A TWO J.-L.AVALS AAA AOA/A7A.D A7 AeCoM 7A/MAAA WaleAF -1 INVENTOR. Coe Dow Govzd BY 777 OaAvey 4,053,845 2 sion has a spectral distribution similar to that of the OPTICALLY PUMPED LASER AMPLIFTERS inducing radiation and may be in a very "sharp' line. This application is a continuation of both of my appli Spontaneously emitted photons, because of the ran cations, Ser. No. 644,035 filed on Mar. 6, 1967 and Ser. dom nature of the zero-point fluctuations, have no defi No. 804,540 filed on Apr. 6, 1959, which were co-pend- 5 nite phase or polarization. Because the zero-point fluc ing herewith and both are now abandoned. My continu tuations contain all frequencies, spontaneously emitted ation application Ser. No. 644,035 was co-pending with radiation has a finite bandwidth, characterized, at the and (1) a divisional application of my application Ser. least, by a Lorentzian line shape. No. 804,540 filed on Apr. 6, 1959, now abandoned, and In thermal equilibrium, the populations of two states (2) a continuation-in-part of my application Ser. No. O are related by the Boltzmann distribution factor: 804,539 filed Apr. 6, 1959, now abandoned. The present invention relates to amplifiers, and par ticularly to optically pumped light amplifiers. Ehigh - Etow A short explanation of the physical principles in KT volved will be helpful in explaining the nature of the 15 invention. It is known that atoms, ions or molecules (hereinafter Thus, in equilibrium the population of a higher energy called molecules) ordinarily exist in so-called "station state is less than that of a lower energy state. In particu ary' states possessing a more or less well defined en lar, the population of a state separated from the lowest ergy. While in such a state a molecule does not exhibit by an optical frequency is practically nil at ordinary an oscillating electric or magnetic moment. However, temperatures. Induced transitions under these condi since a molecule is made up of charged particles, it will tions necessarily absorb photons from the radiation be perturbed by any oscillating electric or magnetic field. field in which it may lie. When so perturbed, a molecule The foregoing principles can be utilized to devise originally known to be definitely in stationary state "a" 25 apparatus for microwave amplification by stimulated will possess a certain probability of being found in state emission of radiation which has been termed a MASER. “b' with different energy. When in such a "mixed' If by some means the population of a higher energy state, the molecule may exhibit an oscillating electric or state is made larger than that of a lower energy state, magnetic moment (i.e., it may appear as a system of 30 induced transitions must necessarily result in the emis oscillating charges, or charges in changing orbits). A sion of photons to the radiation field. Thus a molecule molecule will undergo a transition from state 'a' to may emit spontaneously a photon which in turn may state 'b' (i.e., have a large probability of being in state induce coherent emissions in neighboring molecules, "b') if the induced electric or magnetic moment oscil adding to the total radiation energy. If the transition is lates with almost the same frequency as the applied is at a microwave frequency, the system may be enclosed electric or magnetic field, and if the polarizations and in a cavity resonant at the same frequency and the es phases of the oscillations correspond. The frequency of cape of the photons prevented. If the power loss from the oscillating moment is determined by the Einstein the cavity is less than the power emitted from the mole relationship: cules, the system will oscillate with a frequency which fluctuates much less than the (Lorentz) bandwidth of the transition. The condition for MASER oscillation in where a gas is that the excess population density vo E the oscillation frequency h = Planok's constant h N - Na >> - - - AE = the energy difference between the two molecu 45 8ar pro lar states. The same equation E = hly gives the energy of the if the gas fills the cavity, photons associated with the electro-magnetic field. The T = T = T, is the relaxation time or state lifetime. photon density is proportional to the energy density of Q = the "quality factor' of the cavity. the field. During a transition, a photon or "quantum' 50 p is the oscillating electric or magnetic moment char electro-magnetic energy is emitted to or absorbed from acterizing the transition. the field, depending on whether the molecule is chang If the condition for oscillation is not quite met but ing from a higher to lower energy state or vice-versa. external power is coupled into the cavity, the "sensi Even when there is no radiation energy density of the tized' or "pumped' molecules will add to or amplify right frequency directly observable at the molecule, 55 the signal. Because power is lost through the output spontaneous transitions occur from higher to lower coupling, the condition for infinite gain, at optimum states with the emission of photons. These transitions output, is are actually induced by random fluctuations in the elec tro-magnetic field of so-called "empty' space. The photons emitted during an induced transition N - N --rpr unloaded have the same phase and polarization as the inducing wave - i.e., they are "coherent' with it. A single atom This amplification adds very little random "noise' to may radiate a photon in any direction. However many the amplified signal. The minimum noise is determined atoms distributed over a finite volume and radiating by thermal fluctuations in the radiation field or by ran coherently cooperate to generate a wave having the 65 dom spontaneous emission, whichever is larger.
Load more

Recommended publications
  • From Theory to the First Working Laser Laser History—Part I
    I feature_ laser history From theory to the first working laser Laser history—Part I Author_Ingmar Ingenegeren, Germany _The principle of both maser (microwave am- 19 US patents) using a ruby laser. Both were nom- plification by stimulated emission of radiation) inated for the Nobel Prize. Gábor received the 1971 and laser (light amplification by stimulated emis- Nobel Prize in Physics for the invention and devel- sion of radiation) were first described in 1917 by opment of the holographic method. To a friend he Albert Einstein (Fig.1) in “Zur Quantentheorie der wrote that he was ashamed to get this prize for Strahlung”, as the so called ‘stimulated emission’, such a simple invention. He was the owner of more based on Niels Bohr’s quantum theory, postulated than a hundred patents. in 1913, which explains the actions of electrons in- side atoms. Einstein (born in Germany, 14 March In 1954 at the Columbia University in New York, 1879–18 April 1955) received the Nobel Prize for Charles Townes (born in the USA, 28 July 1915–to- physics in 1921, and Bohr (born in Denmark, 7 Oc- day, Fig. 2) and Arthur Schawlow (born in the USA, tober 1885–18 November 1962) in 1922. 5 Mai 1921–28 April 1999, Fig. 3) invented the maser, using ammonia gas and microwaves which In 1947 Dennis Gábor (born in Hungarian, 5 led to the granting of a patent on March 24, 1959. June 1900–8 February 1972) developed the theory The maser was used to amplify radio signals and as of holography, which requires laser light for its re- an ultra sensitive detector for space research.
    [Show full text]
  • The Innovation Mindset Through Real-World Lessons from Inventors
    BUILDING THE INNOVATION MINDSET THROUGH REAL-WORLD LESSONS FROM INVENTORS Before STEM (science, technology, engineering and COLLABORATION mathematics) and invention education became widely recognized as effective methods of teaching 21st-century skills, the National Inventors Hall of Fame® (NIHF) began crafting education programs that promote creativity. For more than 30 years, we have collaborated with our NIHF Inductees to develop meaningful opportunities for children to engage in hands-on innovation. Informed by lessons and stories from our Inductees’ professional lives, we have identified nine essential skills and traits that turn creative potential into tangible results. We call this the Innovation Mindset. Each year, while developing new curricula, our education team uses the Innovation Mindset as a guide to ensure that all participants in our in-person and at-home programs are developing the vital skills they need to succeed. Because many COLLABORATION of today’s students will likely enter a workforce filled with jobs that do not yet exist,1 we believe that one of the best ways to her life, she made the decision to do whatever it took to lead a prepare them is to teach them how to adapt and innovate when productive and active life. faced with challenges and adversity. She started learning Braille at age 15 and became so proficient By exploring the stories of NIHF Inductees, children can learn at reading English Braille that she earned a degree in English from real-world examples of the Innovation Mindset in action. literature from Otemon Gakuin University in Osaka, Japan, in 1982. As she considered what type of career she wanted to pursue, she came across an article that changed her life.
    [Show full text]
  • Today Nov/Dec
    LIALIA TODAY TODAY The Official Newsletter of the Laser Institute of America The professional society dedicated to fostering lasers, laser applications, and laser safety worldwide. Volume 13, Number 6 November/December 2005 In ICALEO® 2005 Meets International Challenge The by Jack Dyer, Contributing Editor he 24th International Congress on The very large international presence had News... Applications of Lasers & Electro- participants from Europe, Asia, the United Laser-Etching TOptics (ICALEO®) in Miami, Fla. Kingdom, Canada and the United States. In Promotes Egg Safety starting Oct. 31, began just days after Hurricane addition to over 400 from the U.S., Germany Eggs that are laser-etched Wilma tore through the southern part of Florida. had 47, Japan 31, United Kingdom 23, Finland with an expiration date and a All attendees, nevertheless, showed great inter- 14, Canada 19, France 6, Netherlands 7, and code that traces the egg back est in overview presentations on laser diodes, Ukraine, Poland, Australia and several other to where it was packaged are fiber lasers and new market opportunities. countries made up the balance. now available in the U.S., The commercial advent of many new laser reported the Sept. 30 issue of General Congress systems has dominated the laser world the past Optics.org. Developed by General Congress Chair Andreas Ostendorf, several years, and Dr. Ostendorf said, the ple- EggFusion, the laser system CEO of Laser Zentrum Hannover e.V. in nary session showed how these sources can be etches a permanent, easy-to- Germany, opened with “ICALEO over these 24 used for new applications. read and tamper-proof mark years has fulfilled exceptionally well the LIA on the eggshell that allows mission of fostering lasers, laser applications, Plenary: New Lasers – New Markets consumers to see when the and laser safety worldwide.
    [Show full text]
  • Director's Matters
    Monday, January 25, 2010 Director's Matters To mark the 50th anniversary of the invention of the laser, several scientific societies have joined together to promote LaserFest, a yearlong celebration of how this valuable tool for science has transformed our lives—from applications in manufacturing and medicine, to communication and scientific research. OSA, APS, SPIE, and IEEE Photonics Society, with dozens of additional partners including AIP and several other Member Societies, will be sponsoring LaserFest activities throughout the year. For starters, I've asked Greg Good of AIP's History Center to offer some insights on the history of this important invention. Enjoy! —Fred Rubies and lasers in the summer of 1960 Guest column by Greg Good, director, AIP Center for History of Physics Scientific discovery and technological invention have long been intertwined. Such developments as the laser usually emerge from the frenzied, highly interactive, complicated, and competitive work of many individuals—in the case of the laser, shifting teams of individuals. Several characteristic institutions of modern science were involved: industrial research labs, university science departments, science conferences, and the courts and patent system. A critical element was the "research teams," with each team focused on one or another important part of a very complicated set of interlocking problems—technical, potentially profitable, likely worthy of a Nobel Prize. The stakes were high. Historians of science see great value in teasing apart the intricate human interactions that produce such undeniably important developments as the laser—a device now ubiquitous in entertainment, national security, and industry. Historians shrink, however, at oversimplification. Which development was the single crucial one? Who was the inventor of the laser? These questions direct us away from more important ones.
    [Show full text]
  • Historical Remarks on Laser Science and Applications
    2443-1 Winter College on Optics: Trends in Laser Development and Multidisciplinary Applications to Science and Industry 4 - 15 February 2013 Historical Remarks on Laser Science and Applications O. Svelto Politecnico di Milano Italy .8947.(&1*2&708 43&8*7 (.*3(*&3)551.(&9.438 Orazio Svelto Polytechnic School of Milano National Academy of Lincei International Center for Theoretical Physics Winter College on Optics Trieste, February 4-5, 2013 42*33.;*78&7>&9*8 ♦May 16, 1960: First laser action achieved by Theodore H. Maiman (Ruby Laser). Beginning of laser era ♦August 1961 : First observation of optical harmonic generation (Peter Franken). Beginning of nonlinear optics ♦1962: First semiconductor laser (R.N. Hall). Beginning of, possibly, the most important laser ♦1965: First ultrashort-pulse generation (A.J. DeMaria). Beginning of ultrafast optical sciences 1&34+9-.8!&10 ♦ A prologue: the race to make the first laser ♦ The invention of the ruby laser ♦ The invention of the semiconductor laser ♦ Early developments in laser science (1960-1970) ♦ The birth of nonlinear optics Very coarse review of some of most important achievements with a few anedocts and curiosities 1&34+9-.8!&10 ♦ A bridge between nonlinear optics and laser physics: ultrafast laser science ♦ A bridge between high-resolution spectrosocpy and ultrafast lasers: The frequency comb ♦ Historical remarks on Nobel Prizes ♦ Early developments in laser applications (1960-1970) ♦ Conclusions Very coarse review of some of most important points with a few anedocts and curiosities 57414,:* : !-*7&(*94 2&0* 9-*+.7891&8*7 9&79.3,4+9-*&(* ♦ Race started with Schawlow and Townes paper (middle 1958, i.e.
    [Show full text]
  • Edited from Wikipedia
    Laser (Edited from Wikipedia) SUMMARY A laser is a machine that makes an amplified, single-color source of light. The beam of light from the laser does not get wider or weaker as most sources of light do. It uses special gases or crystals to make the light with only a single color. Then mirrors are used to amplify (make stronger) that color of light and to make all the light travel in one direction, so it stays as a narrow beam, sometimes called a collimated beam. When pointed at something, this narrow beam makes a single point of light. All of the energy of the light stays in that one narrow beam instead of spreading out like a flashlight (electric torch). The word "laser" is an acronym for "light amplification by stimulated emission of radiation". A laser creates light by special actions involving a material called an "optical gain medium". Energy is put into this material using an 'energy pump'. This can be electricity, another light source, or some other source of energy. The energy makes the material go into what is called an excited state. This means the electrons in the material have extra energy, and after a bit of time they will lose that energy. When they lose the energy they will release a photon (a particle of light). The type of optical gain medium used (such as ruby) will change what color (wavelength) will be produced. Releasing photons is the "stimulated emission of radiation" part of laser. Many things can radiate light, like a light bulb, but the light will not be organized in one direction and phase.
    [Show full text]
  • Charles H. Townes Papers
    Charles H. Townes Papers A Finding Aid to the Collection in the Library of Congress Manuscript Division, Library of Congress Washington, D.C. 2015 Contact information: http://hdl.loc.gov/loc.mss/mss.contact Additional search options available at: http://hdl.loc.gov/loc.mss/eadmss.ms015019 LC Online Catalog record: http://lccn.loc.gov/mm99084413 Prepared by Melinda K. Friend with the assistance of Tracey R. Barton and Maria Farmer Collection Summary Title: Charles H. Townes Papers Span Dates: 1898-2009 Bulk Dates: (bulk 1948-2000) ID No.: MSS84413 Creator: Townes, Charles H. Extent: 109,000 items ; 408 containers plus 1 classified, 3 oversize, and digital files ; 163.6 linear feet Language: Collection material in English Location: Manuscript Division, Library of Congress, Washington, D.C. Summary: Physicist, astrophysicist, and educator. Correspondence, computation notebooks, technical memoranda and notes, patents, teaching files, astronomical observations, grants and projects, subject files, legal files, speeches, writings, biographical material, awards, printed matter, photographs, and other papers relating to Townes's career beginning in 1948. Selected Search Terms The following terms have been used to index the description of this collection in the Library's online catalog. They are grouped by name of person or organization, by subject or location, and by occupation and listed alphabetically therein. People Abella, Isaac D., 1934- --Correspondence. Basov, N. G. (Nikolaĭ Gennadievich), 1922-2001--Correspondence. Chiao, Raymond Y.--Correspondence. Danchi, William Clifford--Correspondence. Dicke, Robert H. (Robert Henry)--Correspondence. Genzel, Reinhard, 1952- --Correspondence. Greyber, Howard D., 1923- --Correspondence. Javan, Ali, 1926- --Correspondence. Letokhov, V. S.--Correspondence. Ottusch, John J.--Correspondence.
    [Show full text]
  • Peter Pitirimovich Sorokin: Laser Pioneer Dedicated to Understanding, Creating, and Using Light Donald S
    RETROSPECTIVE RETROSPECTIVE Peter Pitirimovich Sorokin: Laser pioneer dedicated to understanding, creating, and using light Donald S. Bethunea and James J. Wynneb,1 Peter Pitirimovich Sorokin, a renowned pioneer in Physical Society and the Optical Society of America, laser science, passed away on September 24, 2015, and a Member of the National Academy of Sciences. from injuries suffered during a fall a month earlier. Peter was born on July 10, 1931, in Boston, Peter, an IBM Fellow emeritus, devoted his career to Massachusetts, the son of Pitirim Aleksandrovich understanding, creating, and using light. His 1966 Sorokin and Elena Baratinskaya Sorokin. He grew up in discovery of laser action in organic dyes is extraordi- Winchester, Massachusetts and attended Harvard narily significant. Dye lasers, with their continuous University, where he received a Bachelor of Arts tunability over a broad spectral range, led to a revolu- in 1952 and a doctorate in Applied Physics in 1958. tion in optical spectroscopy and nonlinear optics. In For his doctoral thesis research, under Nicolaas laboratories throughout the world, dye lasers have Bloembergen, Peter created an innovative NMR tech- been put to use in fundamental studies in physics, nique for measuring chemical shifts in cesium halides. chemistry, biology, and medicine. The breadth and Peter joined IBM in 1958, expecting to continue his significance of this advance may be gauged by the research on NMR, but a new challenge was on the scientific literature: a conservative estimate of the horizon, one that would change physics and Peter’s number of papers published, in which results are career forever. In December 1958, Charles Townes derived from the use of dye lasers, runs into the tens and Arthur Schawlow published a paper in Physical of thousands.
    [Show full text]
  • Ultrafast Laser: the 4Th Element—Mode Locker
    Ultrafast Sources (SoSe 2021) Francesca Calegari & Franz Kärtner, Bldg. 99, Room O3.111 & O3.097 Email & phone: [email protected], 040 8998 6365 [email protected], 040 8998 6350 Office hour: Tuesday, 14.00 - 15.00 Lectures: Tue 12:00-13:30 and Th 15:00-16:30, Online using Zoom and Slack Recitations: Th 16:45-18:15 Start: 06.04.2019 with link https://uni-hamburg.zoom.us/j/98925718145?pwd=d3hFOUZUVWZjTStXaFdSN2p4YjVMUT09 Meeting ID: 989 2571 8145 Passcode: 2021UFSo Teaching Assistants: Felix Rritzkowsky, Office 99.O3.129, phone 040 8998 - 6496, E-mail: [email protected] à send email to for Slack access Anne-Lise Viotti, Office 25B.129, phone 040 8998 - 5597, E-mail: [email protected] Voumard Thibault, Office 99.O1.033, phone 040 8998 - 6387, E-mail: [email protected] Vincent Wanie, Office 222.O1.110, phone 040 8998 - 3124, E-mail: [email protected] Course Secretary: Uta Freydank O3.095, phone x-6351, E-mail: [email protected] Class website: https://ufox.cfel.de/teaching/summer_semester_2021 1 Prerequisites: Basic courses in Electrodynamics and Quantum Mechanics Required Text: Class notes can be downloaded. Requirements: 7 Problem Sets, Term Paper, and Term paper presentation Collaboration on problem sets is encouraged. Grade breakdown: Problem set (25%), Participation (25%), Oral Exam (40%) Recommended Text: Ultrafast Optics, A. M. Weiner, Hoboken, NJ, Wiley 2009. Additional References: § Waves and Fields in Optoelectronics, H. A. Haus, Prentice Hall, NJ, 1984 § Ultrashort laser pulse phenomena: fundamentals, techniques, and applications on a femtosecond time scale, J.-C.
    [Show full text]
  • Dreaming of Death Rays
    COMMENT BOOKS & ARTS The sample, they deduced after PHYSICS many unexpected twists and turns, had probably been found on Russia’s remote, volcanic Kamchatka Peninsula. Steinhardt led an expedition there in Dreaming of death rays 2011 — a wild scavenger hunt search- ing for the stream that the team thought Lasers have long held allure for physics, the military contained the original source. The and science fiction, finds Luke Fleet. group ultimately worked out that the speck came from a meteorite that also contained a second natural quasicrystal, asers first emerged nearly 60 years of the current US dubbed decagonite. ago, but the idea of using powerful president), declared This book is a front-row seat to history beams of heat or light is hardly new. it too speculative. as it is made. For quasicrystal aficionados LIn the third century bc, for instance, Greek The United States like me, it is riveting. For anyone who has scientist Archimedes allegedly used mirrors was hardly alone in reflecting the Sun’s rays to attack Roman its fervour for a death ships off Sicily. Millennia later, ‘death rays’ — ray. Before the Sec- concentrated light or electricity — became ond World War, the a science-fiction trope, from H. G. Wells’s British air ministry 1898 The War of the Worlds to the Star Wars offered a bounty of franchise. Lasers, Death £1,000 (more than Rays, and the As often happens, futurist fiction sparked Long, Strange £60,000 (US$76,000) the real thing. And that’s the story told in Quest for the today) to anyone TRUSTEES OF PRINCETON UNIV.
    [Show full text]
  • Ti:Sapphire Laser •Excimer Laser, Chemical Laser •Nd:YAG Laser, Ti:Saph Laser
    “Coherent Light Sources" A pedestrian guide Credit: www.national.com Experimental Methods in Physics [2011-2012] J-D Ganiere EPFL - SB - ICMP - IPEQ CH - 1015 Lausanne IPEQ - ICMP - SB - EPFL Station 3 CH - 1015 LAUSANNE jeudi, 1 décembre 2011 The context Optical spectroscopy coherent light light light light sample sourcesource analyzer detector Lasers J-D Ganiere 2 MEP/2011-2012 jeudi, 1 décembre 2011 Bibliography For the curious or the beginners Introduction aux lasers Daniel O’Shea, W. Callen, W.T. Rhode, Eyrolles 1977 For people interested in the domain, but who do not like too much the theory ... Principles of lasers Orazio Svelto, D.C. Hanna, Plenum Press 1982 For those who love the theory ... and the lasers Laser Physics M. Sargent, M. Scully, W. Lamb Addison-Wesley 1974 On the Internet Wikipedia Encyclopedia of Laser Physics and Technology - http://www.rp-photonics.com/ J-D Ganiere 3 MEP/2011-2012 jeudi, 1 décembre 2011 Content Introduction • history • principle, intuitive aspects, characteristics • what we can learn from the 2 levels system, NH3 Maser Laser • gain - absorption, linewidth • 3-4 levels models • Optical feedback, threshold conditions • Single line, single frequency operating modes • pulsed lasers (Q-switched, mode-locked lasers) Examples + • He-Ne, CO2, Ar , Nd:YAG, Ti:saph, semiconductor lasers J-D Ganiere 4 MEP/2011-2012 jeudi, 1 décembre 2011 • history • principle, intuitive aspects, Lasers characteristics • 2 levels systems 1917 A. Einstein, stimulated emission Iy Iy & & stimulated emission & & Iy 1950 C.H. Townes, Maser (Microwave Amplification of Stimulated Emission of Radiation) The Inventor, The Nobel Laureates, and the Thirty-Year Patent War 1957 G.
    [Show full text]
  • 55Th Anniversary of the ...Onal Year of Light Blog Copia
    29/5/2015 55th anniversary of the laser’s invention | International Year of Light Blog International Year of Light Blog 55th anniversary of the laser’s invention MAY 27, 2015MAY 27, 2015 LIGHT2015 1 COMMENT Fifty five years ago the laser, one of the most important and versatile scientific instruments of all time, was invented. It was on 16 May 1960, that the North American physicist and engineer, Theodore Maiman (http://en.wikipedia.org/wiki/Theodore_Harold_Maiman), obtained the first laser emission. (https://light2015blogdotorg.files.wordpress.com/2015/05/maiman.jpg) Theodore Maiman (1927-2007), winner of the Wolf Foundation Prize in Physics, 1983 Credit: AIP Emilio Segre Visual Archives. This date is therefore of great importance not only for those of us who carry out research in the field of optics and other scientific fields, but also for the general public who use laser devices in their daily lives. CD, DVD and Blu-ray players, laser printers, barcode readers, and fibre-optic communication systems that connect to the worldwide web and Internet are just a few of the many examples of laser applications in our daily life. Lasers also have a range of important biomedical applications; for example they are used to correct myopia, treat certain tumours and even whiten teeth, not to mention the beauty clinics that continually bombard us with advertisements for laser depilation, which has become so popular nowadays. However, the laser is of great importance not only due to its numerous scientific and commercial applications or the fact that it is the essential tool in various state-of-the-art technologies but also because it was a key factor in the boom experienced by optics in the second half of the last century.
    [Show full text]