DOCSLIB.ORG

Early History of Fourier Transform Spectroscopy

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Early History of Fourier Transform Spectroscopy Infrared Phys. Vol. 24, No. 2/3. pp. 69-93, 1984 0020-0891/84 $3.00 + 0.00 Printed in Great Britain. All rights reserved Copyright !c 1984 Pergamon Press Ltd EARLY HISTORY OF FOURIER TRANSFORM SPECTROSCOPY PIERRE CONNES Service d’Akonomie du CNRS, B.P. No. 3, 91370 Verrieres-le-Buisson, France (Received 31 October 1983) Abstract-This is an attempt to explain how and why the stage was set for the appearance on the scene of Fourier transform spectroscopy (FTS) in the 1950s and not a whit before. The play begins 100 years earlier with Fizeau and Foucault who first produced high path-difference interference phenomena and used them for measuring solar spectrum wavelengths in the near IR. Next, the story unfolds with Michelson’s contribution, which led to important discoveries around 1890: the hyperfine structures and widths of atomic lines. Somewhat less well known is the Rubens interferometric technique, presented in 1910, because no such striking results were ever collected; still, it represented a distinct advance over the Michelson one. What is the reason why Michelson, Rubens and Lord Rayleigh (who made no experiments himself but understood all about them) never managed to get together and propose the modern form of FTS? Part of the responsibility we must ascribe to chance; however, sufficient motivation could not be felt as long as basic noise limitations had not been understood and closely approached. INTRODUCTION The Durham Conference has just demonstrated that Fourier transform spectroscopy (FTS) is now one of the most versatile and widely useful tools in the paraphernalia of modern optics. Will it become one of the permanent features of the landscape, just like-let us say-the Cathedral? Such a prediction would be risky of course; but any participant who briefly stole away from one of the less thrilling sessions and trespassed across the Close, surely discovered that all the great surviving medieval cathedrals are first of all things of the mind: destroyed, rebuilt, enlarged or mutilated, plastered all over and then joyfully restored and rediscovered. What truly endures is oft more the spirit than the stones. At the dissipation rate of all things modern, our present interferometers (some of them anyhow) will be museum pieces before the turn of the century-millenium, and likewise most of our analysis or recording techniques. But the basic principles involved might well exhibit far greater staying power, and earn a permanent niche on the shelves of scientific methodology (see Note l).* Where do they come from? All involved in FTS realize that the independent work of Fellgett and Jacquinot about 30 years ago is unquestionably at the origin of the whole development (see Note 2). They also know of the classical results of Michelson, a trace of which is still found in textbooks, but only vaguely. Few are even aware of the work of Rubens in the field, or realize that the modern form of FTS was almost discovered around 1910; if it had been, much of the development of twentieth century spectroscopy would have been different, particularly of course in the IR. Why was it not discovered in actual fact? Was the prime reason insufficient mathematical understanding, immature technology, absence of motivation, or just the lack of the right people (the last being of course no valid historical explanation)? How much of the basic advantage of FTS (as we understand it today) was already seen? How close to the modern devices were the turn of the century interferometers? And what is the essential change of scene that made possible-and practical-the technique that had failed 40 years before? The following brief (and amateurish) historical study will attempt to answer these questions. It will not start with Fourier, whose contribution is of course essential but had originally nothing to do with optics. For the purpose of our demonstration, the story begins by experimental advances around the middle of the last century. *Notes 1-7 can be found at the end of the article. 69 70 PIERRECONNES I. HIPPOLYTE FIZEAU (1819-1896) AND LEON FOUCAULT (1819.-1868) Born within a few days of each other, Fizeau and Foucault at first tackled several fundamental problems of experimental optics together; after they split, in 1849, they went on in competition. and produced equally brilliant results, We are concerned here with a minor part of that work: their contribution to interference spectroscopy. Fizeau and Foucault initiated two distinct lines of research which were much later to converge and make present-day FTS possible: the production of interferences at high path d@erence, and the recording of IR int~~fi~renceJringes, leading to the first measurement of IR wavelengths. Prior to 1845, no interference phenomena seem to have been observed, or at least understood and properly analysed, for path differences greater than a few wavelengths. Then Fizeau and Foucault published together two brief Notes”’ “ Sur le phinomene des interferences entre deux rayons de lumiere dans le case des grandes differences de marche”. The authors introduce a new technique: the observation of channelled spectra (thanks to a much improved prism spectroscope) and its systematic use for the measurement of path differences. The source was the sun, and bright and dark bands were counted in between the Fraunhofer lines. Three different interference devices were used (Fig. 1): “With Fresnel mirrors, we have observed interference when the path difference for blue rays near line F was 1737 waves. Through reflexion upon both surfaces of a thin plate, interference was noticed when the path difference went up to 3406 waves. With crystalline plates the phenomenon has been followed for remarkably high thick- nesses . ‘* In the second Note, the not-so-thin isotropic plate thickness went up to 1 mm and path difference to “seven or eight thousand times the fundamental interval A”, thanks to the use of up to five prisms in series. (See Note 3.) Fourteen years later, Fizeau (by then no longer paired with Foucault), was to take up again the question of large path differences, but with a different source. His paper,“’ “Note sur la lumiere du sodium brulant dans lair”, was about a popular subject at the time; indeed, he refers to the “many and important results present in the work of M. M. Kirchhoff and Bunsen”. Fizeau is here mostly concerned with his own discovery of an inuerteci pair of D lines from a piece of burning sodium; but he mentions almost incidentally that from an ordinary sodium flame he has obtained: i‘ . the phenomenon of Newton rings, observed with that very simple light, by normal reflexion on the two surfaces of plates that are relatively very thick for such phenomena, since the thickness went up to 10.058 mm, corresponding to a ring of order 52193.” A detailed account is promised “in my next work”. Thanks to the fat pile of scribbled laboratory notes preserved at the Academic, we can follow Fizeau’s progress: he was building the first variable-path interferometer for wavelength measurement by fringe counting (Fig. 2) surely the ancestor of all present so-called “Fourier interferometers” (a particularly absurd contraction). The results were presented a few months later, somewhat hidden away within a paper on interference measurement of refractive index thermal variation for various solids. lh) The small instrument built by Duboscq is described, together with the now familiar sight of Newton’s rings (here observed as “Fizeau fringes” between a plane and spherical glass surface) expanding or contracting when the separation is changed. Fizeau notices and explains correctly the successive coincidences between the fringes from the two D lines, up to the 52nd period of the phenomenon, i.e. 50,000 fringes and a plate separation of 15 mm. The red line of lithium is also observed. and the wavelength given from the coincidences with the D lines. There is no attempt yet to deduce wavelengths from the known pitch of the screw. However, in,fine, the remarkable stability of fringes seen on a thick glass plate (at constant temperature) is ncticed; it is estimated that with the path difference being about 50,000 fringes and a 1/2&h of a fringe motion being easy to detect, the stability must be better than 10. ‘. Fizeau concludes by expressing the hope of important applications. From this remark. all of modern length metrology was to arise. fi PIERRE CONNES Fig. 2. Laboratory note of Fizeau, dated 3 February 1862, illustrating the mechanical design of the first variable-path interferometer for wavelength measurement by fringe counting: “I have made an agreement with Mr Duboscq for constructing a small instrument suitable for measuring the wavelengths of light. .” The device shown is a differential screw with two nuts, one fixed (pitch 0.5 mm) and one mobile (pitch 0.5 x 20/21 mm). For sodium light Fizeau computes a count of 85 fringes/revolution. Also preserved is the draft of a letter to Duboscq (a well remembered instrument maker), discussing some points and ending with the plea: “. I rely on your promise of actively pushing the work on this small instrument which 1 find quite indispensable at present. .“. Results were to be given soon after. in Ref. (6). (Reproduced courtesy of Archives de 1’Acadimie des Sciences. Paris.) As soon as Fizeau and Foucault had perfected their technique they applied it to the detection of IR radiation, and to measuring IR wavelengths. In the first paper,(‘) “Recherches sur les interfkrences des rayons calorifiques”, the source was the sun again, and the detector an alcohol thermometer with a 1 mm dia spherical bulb; a 1” temperature change induced 8 mm of column expansion, which was followed with a microscope; one micrometer division corresponded to l/400-.
Load more

Recommended publications
  • Introduction
    Introduction The following two papers of Planck represent only a very small part of the historical development of our knowledge about the spectral energy distribution of electromagnetic radiation. They are the result of a long series of investigations undertaken not only by Planck (in his work on irreversible processes since 1878, and—stimulated by Maxwell's theory as developed especially by H. Hertz—on the application of thermodynamics to electromagnetic processes, from about 1891) but also by many other scientists who contributed to these experimentally and theoretically in the 19th century or earlier. Planck did not work in a vacuum. On the theoretical side, his formulations were most directly preceded by the theoretical research of Wilhelm Wien, who not only introduced the entropy of (resonator-free) radiation in 1894, but also in 1893 and 1894 discovered several regularities governing the form of the black-body radiation function introduced in 1860 by Gustav Robert Kirchhoff; in 1896 Wien found, simultaneously and independently with Friedrich Paschen, what is now called Wien's distribution law. But Planck also drew on J. H. Poynting's theorem on energy flux, as well as on the law for total radiation obtained by Josef Stefan in 1879 from measure­ ments of earlier authors and derived theoretically in 1884 by L. Boltzmann. Indeed, Planck may have retained as "youthful memories" his intense preoccupation, in his 19th year, with John Tyndall's works on heat radiation. On the other hand the results, as they become evident in these two papers, are only the initial steps in the direction of the quantum theory to be developed later.
    [Show full text]
  • 7.12 Comm Mx
    commentary The quantum centennial One hundred years ago, a simple concept changed our world view forever. spectrum, but did not agree with experi- tion of this experimentally successful radia- Anton Zeilinger ments for all wavelengths. Planck had the tion law from other known laws of physics, When Max Planck announced his quantum advantage of close access to the most recent but he slowly had to accept that he had found assumption in his talk at the German Physical experimental results obtained by Otto Lum- something fundamentally new. Society in Berlin on 14 December 1900, mer and Ernst Pringsheim and by Ferdinand The next important step in the early days nobody, including himself, realized that he Kurlbaum and Heinrich Rubens, also work- of quantum mechanics came in 1905, when was opening the door to a completely new ing in Berlin, on the spectral distribution of Albert Einstein introduced his radical theoretical description of nature. Quantum black-body heat radiation emerging from a hypothesis of quanta of light to explain the physics has had unsurpassed success in hole in a box kept at a certain temperature. photoelectric effect. For a while, this explaining many phenomena — from the Planck eventually found a full explana- remained the only significant instance of the structure of elementary particles, through tion, but only after forcing himself “to an act quantum being taken seriously. Einstein’s the essence of chemical bonds or the nature of of despair” by assuming that energy can only hypothesis met with strong objections from many solid-state phenomena, all the way to be exchanged between the light field inside the his contemporaries, including Planck him- the physics of the early Universe.
    [Show full text]
  • The History of the Spectroscope
    Nuncius 18, fasc. 2 (2003), 808-823 AN UNCONVINCING TRANSFORMATION? MICHELSON’S INTERFERENTIAL SPECTROSCOPY Sean F. Johnston∗ Introduction Albert Abraham Michelson (1852-1931), the American optical physicist best known for his precise determination of the velocity of light and for his experiments concerning aether drift, is less often acknowledged as the creator of new spectroscopic instrumentation and new spectroscopies. His researches on the velocity of light (1878-9) and aether drift (1881-7)1 exploited his excellence in precision optical measurement and metrology. They were closely followed by work on standards of length (1887- 93) and the diameters of stars (1890-1). The measurement of the standard meter brought Michelson to the exploration of spectroscopy. He devised a new method of light analysis relying upon his favourite instrument – a particular configuration of optical interferometer – and published investigations of spectral line separation, Doppler-broadening and simple high-resolution spectra (1887-1898). Contemporaries did not pursue his method. Michelson himself discarded the technique by the end of the decade, promoting a new device, the ‘echelon spectroscope’, as a superior instrument. High-resolution spectroscopy was taken up by others at the turn of the century using the echelon, Fabry-Pérot etalon and similar instruments. Michelson’s ‘Light Wave Analysis’ was largely forgotten, but was ‘rediscovered’ c1950 and developed over the following three decades into a technique rechristened ‘Fourier transform spectroscopy’.2
    [Show full text]
  • Max Planck and the Birth of the Quantum Hypothesis
    Max Planck and the birth of the quantum hypothesis Michael Nauenberg Department of Physics, University of California, Santa Cruz, California 95060 (Received 25 August 2015; accepted 14 June 2016) Based on the functional dependence of entropy on energy, and on Wien’s distribution for black- body radiation, Max Planck obtained a formula for this radiation by an interpolation relation that fitted the experimental measurements of thermal radiation at the Physikalisch Technishe Reichanstalt (PTR) in Berlin in the late 19th century. Surprisingly, his purely phenomenological result turned out to be not just an approximation, as would have been expected, but an exact relation. To obtain a physical interpretation for his formula, Planck then turned to Boltzmann’s 1877 paper on the statistical interpretation of entropy, which led him to introduce the fundamental concept of energy discreteness into physics. A novel aspect of our account that has been missed in previous historical studies of Planck’s discovery is to show that Planck could have found his phenomenological formula partially derived in Boltzmann’s paper in terms of a variational parameter. But the dependence of this parameter on temperature is not contained in this paper, and it wasfirst derived by Planck. VC 2016 American Association of Physics Teachers. [http://dx.doi.org/10.1119/1.4955146] I. INTRODUCTION of black-body radiation known as the ultraviolet catastrophe; this occurs when the equipartition theorem for a system in One of the most interesting episodes in the history of sci- thermal equilibrium is applied to the spectral distribution of ence was Max Planck’s introduction of the quantum hypoth- thermal radiation.
    [Show full text]
  • Max Planck in the Social Context
    Notice to the reader. This is the provisional Version of a text to be included into a volume on the epistemology of some physieists, edited by John Blackmore. In the text actually submitted, the present author argues with some of his coauthors, Their names have been left out here as their contributions may not be available to the readers of the present text. Second edition. MAX PLANCK IN THE SOCIAL CONTEXT E. Broda Institute of Physical Chemistry Vienna University English Summary on Next Page Zusammenfassung Planck war der Begründer der Quantentheorie und daher der modernen Physik. Außerdem hatte er sowohl durch die Kraft seines Charakters als auch durch seine überragenden Funktionen im wissenschaftlichen Leben starken öffentlichen Einfluß. In bezug auf die Stellung zur Atomistik ging Planck, als er sein Strahlungsgesetz begründete und die Quantisierung einführte, von Mach zu Boltzmann über. Einstein war zeit seines Lebens ein Verfechter der Atomistik, während Mach bis zum Ende ein Gegner blieb. Planck war von Anfang an ein Förderer der Relativitätstheorie und Einsteins. In der Weimarer Republik trat er für Einstein gegen die soge­ nannte "Deutsche Physik" ein. Er hatte sogar den Mut, Einstein noch unter dem Naziregime in Ansprachen zu würdigen. Stets philosophisch interessiert, stand Planck zuerst im Banne des Positivismus von Mach, doch wandte er sich später ähnlich wie Einstein dem Realismus zu. Boltzmann war schon immer Realist und Materialist ge­ wesen. Man verdankt Planck auch wichtige Überlegungen zum Problem der Willensfreiheit. In der Politik war Planck vor dem ersten Weltkrieg ein konventio­ neller, konservativer preußisch-deutscher Patriot. Nach der Machtergrei­ fung Hitlers ging er jedoch auf Distanz zum Staat.
    [Show full text]
  • Einstein - from Ulm to Princeton Frank Steiner, Department of Theoretical Physics, University of Ulm, Albert-Einstein-Allee 11, D-89069 Ulm, Germany
    FEATURES Einstein - from Ulm to Princeton Frank Steiner, Department of Theoretical Physics, University of Ulm, Albert-Einstein-Allee 11, D-89069 Ulm, Germany L ast year, the University of Ulm, the City of Ulm, and the Ger­ man Physical Society celebrated the 125th birthday of Albert Einstein, who was born in Ulm on 14 Marchl879. Being fully aware of the multitude of events expected to happen at many places during the "World Year of Physics 2005", it was felt appro­ priate to commemorate Einstein at his birthplace already in 2004. This followed a long tradition in Ulm, where previously Einstein's 70th and 100th birthday had been celebrated in 1949 and 1979, respectively. The celebration in Ulm consisted of a large number of events during a period of nine months. To bring Einstein's work, ideas and life to a broad audience, a series of a dozen of public lectures [1] were given by physicists and historians that met with great response. An "Albert-Einstein-Schülerwettbewerb" (competition for students at secondary schools) was organized, and a new "Einstein Opera" commissioned by the City of Ulm was per­ formed at the Ulm Theatre. Furthermore, an "Einstein Exhibition" was installed which saw many visitors over several months. On Einstein's birthday, 14 March 2004, the Mayor of the City of Ulm held a "Festakt" in Ulm's Einstein Hall in the presence of the President of the Federal Republic of Germany and the Prime Min­ ister of Baden-Württemberg. In the evening of the same day, the opening ceremony of the Spring Meeting ("Frühjahrstagung") of the German Physical Society took place at the University of Ulm.
    [Show full text]
  • The Quantum Leap
    MILESTONES MILESTONE 3 described by his formula, partially guided by the work of Ludwig Boltzmann on entropy. However, The quantum leap there was one revolutionary assump- tion that he had to make: that light aimed at constructing a standard for was emitted and absorbed in discrete the measurement of illumination packets of energy — quanta. These intensities, directed him towards were not a feature of heat radiation heat radiation. He revisited Gustav alone, but, as Albert Einstein showed Kirchhoff’s theoretical studies of in 1905, also of light. Einstein used black-body radiation, which implied the term Lichtquant, or quantum that when a substance capable of of light. Only in 1926 was the word absorbing and emitting radiation is ‘photon’ introduced, by the chemist enclosed in a cavity with perfectly Gilbert Lewis. His theory of a “hypo- reflecting walls, the spectral distribu- thetical new atom that is not light tion of the observed radiation at but plays an essential part in every equilibrium is a function only of process of radiation” did not hold up, temperature and is independent of but the name ‘photon’ stuck. the substance involved. Intrigued by Without setting out to do so, such an ‘absolute’ law, Plank devoted Planck had rocked the edifice of himself, from 1896, to finding an physics to its very foundations. “His explanation for it. was, by nature, a conservative mind,” Parallel works on black-body wrote Max Born in an obituary radiation produced confusing results. of Planck, “he had nothing of the Lord Rayleigh had found a law revolutionary and was thoroughly (which, with James Jeans, he later sceptical about speculations.
    [Show full text]
  • Heinrich Rubens
    Heinrich Rubens. Von Wilhelm Westp£al, Berlin. Am 17. Juli _1922 hat Heinrlch Rubens naeh Assistenten am .Berliner Insti~ut ernannt. Zu ]angem, schwerem Leiden ,die Augen geschlossen. dieser Zeit war es, Ms die Entdeekung tier elek- Nit ibm ist nicht n ur ein Forscher wo~, Weltruf, trischen WelIen und ihrer Eigenschaf%en durch nicht nur einer tier erfo]greiehste,n akademisehen Heinrich Hertz in entscheidenc}er Weise einem Lehrer Deutsehlands .da,hingegangen, sondern grol]en Teil seiner kfinftigen Lebensarbeit <tie aueh ein Mensch yon eigenartigem Gepr~ge, dem Wege wiesen. I.n seinem ~er[ihmten Vc~rtrage auf eine grolhe Zahl glterm: un~d jiingerer Faeh- der Naturf,or.scherversammlung in tIeidel'berg be- genossen in Verehrung anhingem Dieser Ver- tonte Hertz die Notwendigkeit, die Briieke yon ehrung sell @ieses, seinem Andenken gewidme~e der Op~ik zur Elelctrizitittsle'hre nnn'mehr auch Heft A~sdruck geben ,dadurch, dal3 sein Leben yon cter optisehen Seite her zu sch]agem DaB und Forsehen dutch d iejenigen Faehgeno~ssen dar- Rubens dieses gelang, mad win es ibm gelang, gestellt wird, welche ih~m als Ass~sZenten am wird immer zu den klassisehen ETeignissen in~ tier Physikalischen Institut der Universit:,tt ]herlin am Gesehichte der Physik gez~ihlt werden. Auf diese lgngsten 'amtlich und Fershnlich nahegestanden Wei.se wurde er vera~n~l.agt, sleh eingeh.en& mi£ tier haben. Wir wol]en damit unserm vecehrten Erforschung des ultraroten Spektratgebietes zu Lehrer ein. beseheidenes Denkmal errleh~cen als ~besch~ftigen, in ,gem er im wahrsten Sinne des Ansgruek einer tiefgeffihlten Dankess.ehuld.
    [Show full text]
  • The “Black Body” and the Quantization of the World
    PTR/PTB: 125 Years of Metrological Research PTB-Mitteilungen 122 (2012), No. 2 The “Black Body” and the Quantization of the World Jörg Hollandt At a temperature above the absolute zero point, each body emits electromagnetic radiation which is referred to as “thermal radiation”. Already in 1860, Gustav Kirchhoff realized that for a body which completely absorbs all incident radiation (absorptivity α = 1), the spectrum of the emitted thermal radiation is independent of the form and the material of the body, and is only a function of the wavelength and of the temperature [1]. Since the time of Kirchhoff, such a body has been called a “black body”. radiation of a black body that has been generated On the basis of the second law of thermodynam- in the cavity. ics, Kirchhoff concluded that – in thermal equi- Initial investigations on these cavity radiators librium – for the same temperature, wavelength led Wien to the formulation of a radiation law in and direction, the directional spectral absorptivity 1896 which was named after him and which led is equal to the directional spectral emissivity. The to the belief for a few years that it would describe spectral emissivity describes a body’s capability to thermal radiation correctly [2]. In the following emit thermal radiation. For a black body, the spec- three years, Lummer and Kurlbaum developed an tral emissivity is thus equal to one for all wave- electrically heated cavity radiator which could gen- lengths, and no body of the same temperature can erate thermal radiation up to 1600 °C. Exact meas- emit more thermal radiation than a black body.
    [Show full text]
  • Mitteilungen 2 Technical and Scientific Journal of the Physikalisch-Technische Bundesanstalt 2012
    MITTEILUNGEN 2 TECHNICAL AND SCIENTIFIC JOURNAL OF THE PHYSIKALISCH-TECHNISCHE BUNDESANSTALT 2012 PTR/PTB: 125 Years of Metrological Research MITTEILUNGEN JOURNAL OF THE PHYSIKALISCH-TECHNISCHE BUNDESANSTALT Special Journal for the Economy and Science Official Information Bulletin of the Physikalisch-Technische Bundesanstalt Braunschweig and Berlin Advance copy from: 122nd volume, issue 2, June 2012 Contents PTR/PTB: 125 Years of Metrological Research Chronology 1887–2012 6–61 • Ernst O. Göbel: Preface 3 • Wolfgang Buck: The Intention 4 • Helmut Rechenberg: Helmholtz and the Founding Years 8 • Jörg Hollandt: The “Black Body” and the Quantization of the World 12 • Robert Wynands: The “Kuratorium”, PTB’s Advisory Board 16 • Wolfgang Buck: “New Physics” and a New Structure 20 • Dieter Hoffmann: The Einstein Case 22 • Wolfgang Buck: The Merging of the RMG and the PTR 26 • Dieter Hoffmann: The Physikalisch-Technische Reichsanstalt in the Third Reich 30 • Dieter Hoffmann: The PTR, PTA and DAMG: the Post-war Era 34 • Peter Ulbig, Roman Schwartz: Legal Metrology and the OIML 38 • Wolfgang Schmid: European Metrology 46 • Dieter Kind: The Reunification of Metrology in Germany 50 • Roman Schwartz, Harald Bosse: PTB – A Provider of Metrological Services and a Partner of Industry, Science and Society 56 • Ernst O. Göbel, Jens Simon: PTB at the Beginning of the 21st Century 62 Authors 66 Picture credits 67 Literature 68 Title picture: Together with Werner von Siemens and others, Hermann von Helmholtz campaigned personally for the foundation of the PTR and became its first presi- dent from 1888 to 1894. Imprint The PTB-Mitteilungen are the metrological specialist journal and official infor- mation bulletin of the Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin.
    [Show full text]
  • The History of the Spectroscope
    Johnston, S. F. (2003) An unconvincing transformation? Michelson's interferential spectroscopy. Nuncius:annali di storia della scienza 18(2):pp. 803-823. http://eprints.gla.ac.uk/archive/2893/ Glasgow ePrints Service http://eprints.gla.ac.uk Nuncius 18, fasc. 2 (2003), 808-823 AN UNCONVINCING TRANSFORMATION? MICHELSON’S INTERFERENTIAL SPECTROSCOPY Sean F. Johnston∗ Introduction Albert Abraham Michelson (1852-1931), the American optical physicist best known for his precise determination of the velocity of light and for his experiments concerning aether drift, is less often acknowledged as the creator of new spectroscopic instrumentation and new spectroscopies. His researches on the velocity of light (1878-9) and aether drift (1881-7)1 exploited his excellence in precision optical measurement and metrology. They were closely followed by work on standards of length (1887- 93) and the diameters of stars (1890-1). The measurement of the standard meter brought Michelson to the exploration of spectroscopy. He devised a new method of light analysis relying upon his favourite instrument – a particular configuration of optical interferometer – and published investigations of spectral line separation, Doppler-broadening and simple high-resolution spectra (1887-1898). Contemporaries did not pursue his method. Michelson himself discarded the technique by the end of the decade, promoting a new device, the ‘echelon spectroscope’, as a superior instrument. High-resolution spectroscopy was taken up by others at the turn of the century using the echelon, Fabry-Pérot etalon and similar instruments. Michelson’s ‘Light Wave Analysis’ was largely forgotten, but was ‘rediscovered’ c1950 and developed over the following three decades into a technique rechristened ‘Fourier transform spectroscopy’.2 This paper presents Michelson’s interferometric work as a continuum of personal interests and historical context.
    [Show full text]
  • Gustav Hertz – 85 Jahre Alt! In: Experimentelle Technik Der Physik, 20
    Hertz, Gustav akademischer Titel: Prof. Dr. phil. habil. Dr.-Ing. e. h. Dr. rer. nat. h. c. mult. Prof. in Leipzig: 1954-61 Professor mit Lehrstuhl für Experimentalphysik. Fakultät: 1954-1961 Mathematisch-Naturwissenschaftliche Fakultät – Physikalisches Institut. Lehr- und Experimentalphysik. Quantenphysik. Forschungsgebiete: Feldelektronenmikroskopie. Halbleiterphysik. Elektronenstruktur von Festkörpern. weitere Vornamen: Ludwig Lebensdaten: geboren am 22.07.1887 in Hamburg gestorben am 30.10.1975 in Berlin Vater: Gustav Theodor Hertz (Rechtsanwalt) Mutter: Anna Augusta Hertz geb. Arning (Hausfrau) Konfession: ev.-luth. Lebenslauf: 1893-1896 Vorschule von Herrn Thedsen in Hamburg. 1896-1900 Privat-Realschule von Herrn Dr. Bieber in Hamburg. 1900-1906 Realgymnasium des Johanneums in Hamburg mit Abschluss Abitur. 1906-1907 Studium der Mathematik an der Georg-August-Universität Göttingen (2 Semester). 1907 Studium der Physik bei Arnold Sommerfeld an der Ludwig-Maximilians-Universität Mün 1907-1908 Militärdienst als 1-jähriger Freiwilliger beim Kgl. Sächs. Feld-Artillerie-Reg. Nr. 12 in Dresden. 1908-1911 Studium der Physik und Doktorand am Physikalischen Institut der Universität Berlin. 1911-1914 Wiss. Assistent am Physikalischen Institut der Friedrich-Wilhelms-Universität Berlin. 1914-1915 Einberufung zum Militärdienst und Kriegsteilnahme als Offizier mit Versetzung zur Spezial- Truppe für den Gaskampf (Pionier-Reg. 35) unter Leitung von Prof. Fritz Haber. 7.07.1915 Schwere Verwundung bei einem Gasangriff auf russische Truppen in Polen mit anschließender Entlassung aus der Armee nach mehrmonatigem Lazarettaufenthalt u. Genesungsurlaub. 1915-1917 Wiss. Assistent am Physikalischen Institut der Friedrich-Wilhelms-Universität Berlin. 1917-1920 Privatdozent für Experimentalphysik an der Friedrich-Wilhelms-Universität Berlin. 1920-1925 Wiss. Mitarbeiter im Entwicklungslabor der Glühlampenfabrik Philips in Eindhoven (NL).
    [Show full text]