Abstract
The basic principle of the wide-field telescope invented by the Estonian optician and astronomer Bernhard Schmidt in 1928 ([67–70], E. Schmidt [72]), is that a single concave and spherical mirror used with a pupil stop at its center of curvature has no unique axis and therefore yields equal size images at all points of its field of view. In the third-order theory, the mounting is free from Coma3 and astigmatism Astm3; all images have the same amount of spherical aberration, Sphe3, coming from the spherical mirror. By using a refractive corrector plate at the mirror center of curvature, one therefore yields equally good images in the whole field of view. In the historical context in Europe, three scientists had previously developed the theoretical analysis on aplanatic telescopes in the two-mirror class, but none of them found or realized that the primary mirror could be used off-axis or could be replaced by an on-axis refractive element. Kellner who patented in 1910 [25] several designs using a corrector lens, locates the plate in a wrong position for wide-field compensations. Schmidt placed the aspherical plate at the mirror center of curvature and emphasized the importance of this location for the entrance pupil of the telescope. The curved focal surface is a monocentric sphere with the mirror. In 1930–31, he succeeded in constructing the first wide-field telescope, 36 cm clear aperture at f/1.75, with which he demonstrated the wide-field performance on 7.5 arc degrees during the two subsequent years. He obtained with Wachmann, about two hundred exposures onto curved films showing perfect images. Such astronomical object densities were never seen before. In 1932, Schmidt published his famous article “Ein Lichtstarkes Komafreies Spiegelsystem” [70] and photographies [71]. In fact, his coma-free i.e. aplanatic telescope is also free from third-order astigmatism: nowadays, this is called an anastigmatic telescope. Review papers on B. Schmidt’s work were published by Schorr [73], Mayall [47], Wachmann [84, 85], Kross [27] and more recently by E. Schmidt [72], his nephew.
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References
J.A. Arns, W.S. Colburn, S.C. Barden, Volume phase gratings for spectroscopy, in Current Developments in Optical Design VIII, SPIE Proc., 3779, 313–323 (1999)
J.G. Baker, A family of flat-field cameras, equivalent in performance to the Schmidt cameras, Proc. Am. Philos. Soc., 82, 339 (1940)
J.G. Baker, US Patent No 2 458 132 (1945)
A. Baranne, Un nouveau montage spectrographique, Comptes Rendus, 260, 3283–3286 (1965)
A. Baranne, M. Mayor, J.-L. Poncet, Coravel – A new tool for radial velocity measurements, Vistas Astro., 23, 279–316 (1979)
S.C. Barden, J.A. Arns, W.S. Colburn, Volume-phase holographic gratings, in Current Developments in Optical Design VIII, SPIE Proc., 3779, 313–323 (1999)
M. Born, E. Wolf, Principles of Optics, Cambridge University Press, Cambridge 253 (1999)
O. Boulade, G.R. Lemaitre, L. Vigroux, UV prime focus spectrograph for the CFHT, Astron. Astrophys., 163, 301–306 (1986)
A. Bouwers, in New Optical Systems – Achievements in Optics, Elsevier Edit., Amsterdam (1946)
I.S. Bowen, Spectrographic equipment of the 200-inch Hale telescope, Ap. J. 116, 1–7 (1952)
I.S. Bowen, Schmidt cameras, in Stars and stellar Systems I – Telescopes, G.P. Kuiper and B.M. Middlehurst edts., Univ. of Chicago Press, Chicago 43–61 (1960)
I.S. Bowen, Astronomical optics, Annual Review of Astronomy and Astrophysics, L. Goldberg ed., 5, 45–70 (1967)
C.R. Burch, On the optical see-saw diagram, MNRAS 102, 159–165 (1942)
C. Carathéodory, Geometische Optik, Springer edt., Berlin (1937)
C. Carathéodory, Elementare Theorie des Spiegeltelescops von B. Schmidt, B.G. Teubner edt., Leipzig u. Berlin, 1–36 (1940) and Hamburg. Math. Einzelschr., 28 (1940)
H. Chrétien, Le télescope de Newton et le télescope aplanétique, Rev. d’Opt., 1, 13 et 51 (1922)
H. Chrétien, Le Calcul des Combinaisons Optiques, Sennac Edit., Paris, 346–350 (1958)
A. Couder, Sur un type nouveau de télescope photographique, Comptes Rendus, 183, 1276–1279 (1926)
G. Courtès, New Techniques in Space Astronomy, IAU Conf. Paris, Labuhn & Lüst edt. (1971)
C. Fehrenbach, Principes fondamentaux de classification stellaire, Ann. Astrophys. 10, 257–306 (1947), and 11, 35 (1948)
C. Fehrenbach, R. Burnage, Vitesses radiales mesurées au prisme objectif de 620-mm de l’Observatoire de Haute Provence, Astron. Astrophys. Suppl. Series, 43, 297 (1981)
J. Flamand et coll., Diffraction Gratings Ruled and Holographic, Horiba Jobin-Yvon handbook (2003)
K.G. Henize, The role of surveys in space astronomy, Optical Telescopes Technology, NASA-SP-233, US Gov. Print. Off., Washington DC (1970)
D.O. Henrix, W.H. Christie, Some applications of the Schmidt principle in optical design, Sci. Am., 8, 161, 118–123 (1939)
G.A.H. Kellner, American Patent No 969 785, Fig. 3 (1910)
A. Kerber, Central Zeitg. f. Opt. and Mech., 8, 157 (1886) (see Chrétien’s book)
J. Kross, in L’oeil du grand Tout, Life story of B. Schmidt from its invention to the Palomar Schmidt, Laffont edt., Paris (1997)
A. Lallemand, N. Duchesne, G. Wlerick, Advance in Electronics and Electron Physics, 12, 5 (1960)
G.R. Lemaitre, Reflective Schmidt anastigmat telescopes and pseudo-flat made by elasticity, J. Opt. Soc. Am., 66(12), 1334–1340 (1976)
G.R. Lemaitre, J. Flamand, Spectrographic development of diffraction gratings aspherized by elastic relaxation, Astron. Astrophys., 59(2), 249–253 (1977)
G.R Lemaitre, Sur la résolution des télescopes de Schmidt de type catoptrique, Comptes Rendus Acad. Sc., 288 B, 297 (1979)
G.R. Lemaitre, Asphérisation par relaxation élastique de miroirs astronomiques dont le contour circulaire ou elliptique est encastré ou semi-encastré, Comptes Rendus, 290 B, 171 (1980)
G.R. Lemaitre, Combinaisons optiques à réseaux asphériques: Le spectrographe UV Prime Focus CFHT, Astron. Astrophys. Letters, 103(2), L14–L16 (1981)
G.R. Lemaitre, Optical design with the Schmidt concept, Astronomy with Schmidt Type Telescopes, IAU Coll. Proc., M. Capaccioli edt., Asiago, Reidel publ., 533–548 (1984)
G.R. Lemaitre, L. Vigroux, All-reflective aspherized grating spectrographs at the prime focus of the CFHT, Instrumentation for Ground-based Astronomy, L.B. Robinson ed., Springer-Verlag, New York, 275–295 (1987)
G.R. Lemaitre, D. Kohler, Spectrographes à réseaux asphériques par réflexion: Les Marlys des observatoires de Haute-Provence et de Nanjing, Comptes Rendus Acad. Sc., 308 II, 381–387 (1989)
G.R. Lemaitre, D. Kohler, D. Lacroix, J.-P. Meunier, A. Vin, All reflective aspherized grating spectrographs for Haute-Provence and Nanjing observatories: Marlys and Carelec, Astron. Astrophys. 228, 546–558 (1990)
G.R. Lemaitre, E.H. Richardson, Ground-based and orbital off-axis aspherized grating imagerspectrographs: ISARD/Pic-du-Midi and OSIRIS/Odin-Orbiter, Optical Astronomical Instrumentation, SPIE Proc., 3355, 682–695 (1998)
E.H. Linfoot, The optics of the Schmidt camera, M.N.R.A.S. 109, 279–297 (1949)
E.H. Linfoot, E. Wolf, On the corrector plates of Schmidt cameras, J. Opt. Soc. Am. 39, 752 (1949)
E.H. Linfoot, Two-mirror systems, Recent Advances in Optics, Clarendon edt., Oxford, 277, Chap. 3, 176–183 (1955)
E.G. Loewen, D. Maystre, R.C. McPhedran, Correlation between efficiency of diffraction gratings and theoretical calculations over a wide range, Japan J. Appl. Phys., 141, 143–152 (1975)
E.G. Loewen, M. Nevière, D. Maystre, Grating efficiency theory as it applies to blazed and holographic gratings, Appl. Opt., 16(10), 2711–2721 (1977)
D. Lynden-Bell, Exact optics: A unification of optical telescope design, MNRAS, 334, 4, 787–796 (2002)
D. Maksutov, New catadioptric menicus systems, J. Opt. Soc. Am., 34, 270 (1944)
A. Maréchal, G.W. Stroke, Sur l’origine des effets de polarisation et de diffraction dans les réseaux optiques, Comptes Rendus Acad. Sc., 248, 2042–2044 (1959)
N.U. Mayall, Bernhard Schmidt and his coma-free reflector, PASP 58, 282–290 (1946)
D. Maystre, R. Petit, Détermination du champ diffracté par un réseau holographique, Optics Communications, 2(7), 309–311 (1970)
D. Maystre, R. Petit, Sur l’efficacité du réseau échelette, Nouv. Rev. Opt. Appliquée, 2(2), 115–120 (1971)
D. Maystre, Rigorous vector theories of diffraction gratings, in Progress in Optics XXI, E. Wolf edt., Elsevier Sciences publ. (1984)
R.C. McPhedran, D. Maystre, A detailed theoretical study of the anomalies of a sinusoidal diffraction grating, Optica Acta, 21(5), 413–421 1974)
W.C. Meecham, Variational method for the calculation of the distribution of energy reflected from a periodic surface. I., J. Appl. Phys., 27, 361 (1956)
D.R. Montgomery, L.A. Adams, Optics and the Mariner imaging instrument, Appl. Opt., 9, 277 (1970)
M. Nevière, M. Cadilhac, Opt. Commun., 4, 13 (1971)
M. Nevière, P. Vincent, R. Petit, Nouv. Rev. Opt. Appliquée, 5(2), 65–67 (1974)
M. Nevière, D. Maystre, J.-P. Laude, Perfect blazing for transmission gratings, J. Opt. Soc. Am., A-7(9), 1736–1739 (1990)
J. Pavageau, J. Bousquet, Optica Acta, 17, 469 (1970)
R. Petit, M. Cadhilac, Sur la diffraction d’une onde plane par un réseau infiniment conducteur, Comptes Rendus Acad. Sc., B-262, 468–471 (1966)
R. Petit, Optica Acta, 14, 3, 301–310 (1967)
R. Petit, Electromagnetic theory of gratings, in Topics in Current Physics, 22, Springer-Verlag ed. Berlin (1980)
G.M. Popov, New two-mirror systems for astrophysics, Instrumentation in Astronomy, SPIE Proc. 2198, 559–569 (1994)
J.W. Rayleigh (Lord Strutt), On the dynamical theory of gratings, Proc. R. Soc. London, A-79, 349–416 (1907)
J.W. Rayleigh (Lord Strutt), Phil. Mag., 14, 60 (1907)
E.H. Richardson, D. Salmon, The CFHT Herzberg spectrograph, CFHT Bull., Hawaii, 13 (1985)
F.E. Ross, The 48-inch Schmidt Telescope, Ap. J., 92, 400–407 (1940)
B. Schmidt, Original manuscript (1929), conserved by The Academy of Estonia, University of Tallin (and by Erik Schmidt). Several aspherical plate profiles are considered which include a Kerber profile, (1929)
B. Schmidt, Mitteilungen der Hamburger Sternwarte, R. Schorr edt., 10 (1930)
B. Schmidt, A.A. Wachmann, Mitteilungen der Hamburger Sternwarte, R. Schorr edt., 6 and Plate I (1931)
B. Schmidt, Y. Wachmann, Mitteilungen der Hamburger Sternwarte, R. Schorr edt., 11 and Plate I (1932)
B. Schmidt, Ein Lichtstarkes Komafreies Speigelsysten, Central Zeitung für Optik und Mechanik, 52, Heft 2, 25 (1932)
B. Schmidt, Mitteilungen der Hamburger Sternwarte, R. Schorr edt., 10 and Plates I and II (1936)
E. Schmidt, in Optical Illusions, Estonian Academy Publishers (Life story of Bernhard Schmidt), 124–125 (1995)
R. Schorr, Astronomische Nachrichten, Berlin 259, 45 (1936) This review paper on B. Schmidt works was translated into English by N.U. Mayall (see also Wachmann, A.A., Kross, J., Schmidt, E.)
D.J. Schroeder, Astronomical Optics, Academic Press, London (1987)
D.H. Schulte, Auxiliary optical systems for the Kitt Peak Observatory, Appl. Opt., 2(2), 141–151 (1963)
K. Schwarzschild, Untersuchungen zur geometrischen Optik, I, II, III, Göttinger Abh, Neue Folge, Band IV, No. 1 (1905) This article is a general investigation of aplanatic systems obtained with two centred mirrors.
R.D. Sigler, Compound Schmidt telescope designs with nonzero Petzval curvature, Appl. Opt. 14, 2302–2305 (1975)
G.W. Stroke, Revue d’Optique, 39, 350 (1960)
B. Stromgren, Das Schmidtsche Spiegelteleskop, Viert. Astron. Gessellsch, Leipzig, 70, 65–86 (1935)
D.-q. Su, C. Cao, M. Liang, Some new ideas of the optical system of large telescopes,Avanced Technology Optical Telecopes III, SPIE Proc. 628, 498–503 (1986)
D.-q. Su, Researches on Schmidt and achromatic Schmidt telescopes, Acta Astronomica Sinica, 29(4), 384–395 (1988)
D.-q. Su, X. Cui, Active optics in LAMOST, Chin. J. Astron. Astrophys., 4(1), 1–9 (2004)
Y. Väisälä, Uber Spiegelteleskope mit grossem Gesichtsfeld, Astr. Nach., 259, 197–204 (1936)
A.A. Wachmann, From the life of Bernhard Schmidt, Sky and Telescope, November, 4–9 (1955)
A.A. Wachmann, Private communications to Erik Schmidt (1985–90). It appears that B. Schmidt probably did not use the stress polishing technique for making its corrector plate although the plate thickness was thin enough for this to work.
S.-g. Wang, D.-q. Su, Q.-q. Hu, Two telescope configurations for China, Advanced Technology Optical Telescopes IV, SPIE Proc. 2199, 341–351 (1994)
S.-g. Wang, D.-q. Su, Y.-q. Chu, X. Cui, Y.-n. Wang, Special configuration of a very large Schmidt telescope for extensive astronomical spectroscopic observations – LAMOST, Appl. Opt., 35, 25, 5155–5161 (1996)
R.N. Wilson, Reflecting Telescope Optics I, Springer-Verlag edt. New York (1996)
R.W. Wood, Phil. Mag., 4, 396 (1902)
J.D. Wray, F.G. O’Callaghan, Folded all-reflective Schmidt, Space Optics, SPIE Proc., Santa Barbara (1969)
J.D. Wray, H.J. Smith, K.G. Henize, G.R. Carruthers, SPIE Proc. 332, 141 (1982)
F.B. Wright, An aplanatic reflector with a flat field related to the Schmidt telescope, Publ. Astron. Soc. Pac., 47, 300–304 (1935)
C.G. Wynne, MNRAS, 107, 356 (1947a)
C.G. Wynne, Chromatic correction of wide-aperture catadioptric systems, Nature, 160, 91 (1947b)
C.G. Wynne, Two-mirror anastigmats, J. Opt. Soc. Am., 59, 572–580 (1969)
C.G. Wynne, Shorter than a Schmidt, MNRAS, 180, 485–490 (1977)
Y.-t. Zhu, G.R. Lemaitre, LAMOST multi-object spectrographs with aspherized gratings, in Instrument Design for Ground-based Telescopes, SPIE Proc. 4841, 1127–1133 (2002)
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Lemaitre, G. (2009). Optical Design with the Schmidt Concept – Telescopes and Spectrographs. In: Astronomical Optics and Elasticity Theory. Astronomy and Astrophysics Library. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-68905-8_4
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