| 释义 |
▪ I. Scheiner, n.1|ˈʃaɪnə(r)|
The name of Christoph Scheiner (c 1575–1650), German astronomer and experimenter, used in the possessive and (formerly) with of to designate various concepts introduced by him, as Scheiner's experiment (also † experiment of Scheiner) Ophthalm., an experiment to demonstrate accommodation and the focusing ability of the eye in which when two objects are viewed in line through a pair of pinholes made close together in a card held near one eye, the object not in focus appears as a double image (now rare); Scheiner's halo Astron., a faintly luminous halo occasionally observed around the sun or moon at an angle of 23°–32°, due to refraction of light by pyramidal ice crystals in the upper atmosphere.
1870Amer. Jrnl. Med. Sci. LX. 414 In the number of this Journal for January, 1870, will be found a description of a test for ametropia, based on the experiment of *Scheiner. 1886C. M. Culver tr. Landolt's Refraction & Accomm. of Eye iii. 243 When one looks at a small object placed at a distance for which the eye is not adapted, through minute openings, the distance between which is less than the diameter of the pupil, the object appears multiple... This is known as Scheiner's experiment. [1905Compt. Rend. CXL. 1368 Qu'il me soit permis encore d'expliquer la tache irisée, semblable au sommet du halo ordinaire et distante du Soleil de 28°, qu'a vue et mesurée M. Besson. Elle était, sans doute, un fragment du halo de Scheiner.] 1983Jrnl. Physical Chem. LXXXVII. 4177/1 The second sighting of *Scheiner's halo was made in 1677. 1987Sci. Amer. May 51/2 Diamond-shaped ice gives rise to a rarely detected atmospheric phenomenon called Scheiner's halo.
▪ II. Scheiner Photogr.|ˈʃaɪnə(r)|
The name of Julius Scheiner (1858–1913), German astrophysicist, used, usu. attrib., with reference to a way of measuring and expressing the speed of photographic emulsions that he devised, as Scheiner degree, Scheiner scale, Scheiner sensitometer, Scheiner speed, Scheiner system; Scheiner number, a number depending on the logarithm of the least exposure that will give a visible image on development.
1900Astrophysical Jrnl. XI. 91 In a simple experiment with the aid of Scheiner's sensitometer equal degrees of blackening were produced by continuous exposures of 96, 72, 48, 24, 12 secs. Ibid. 98 Remarks on the Scheiner sensitometer. 1911A. Watkins Photography iii. 47 In the case of Wynne, Scheiner, and Warnerke numbers..there is not the same direct proportion between the numbers. Ibid. 332 (Index), Scheiner speeds. 1918J. R. Roebuck Science & Practice of Photogr. 225 ‘n’ is the Scheiner degree and ‘A’ has the value in this case of about 4·4. 1936Discovery June 192/2 The rating [of the exposure meter] agreeing more or less with the Scheiner system. 1938S. G. B. Stubbs et al. Modern Encycl. Photogr. II. 1105/1 The so-called ‘Scheiner speeds’ quoted by Continental manufacturers are in reality not Scheiner speeds at all, as all ‘Scheiner’ measurements are now carried out by the Eder–Hecht method. 1942C. B. Neblette Photography (ed. 4) xiii. 419 The ratio of the exposures between consecutive steps on the Scheiner sensitometer is as 1:1·27. 1962Ibid. (ed. 6) xx. 267/1 The Scheiner speed number was obtained originally by exposing the negative material in a sensitometer with a sector wheel having exposure steps numbered from 1 to 20, with a log exposure difference of 0·15. Ibid. 267/2 In 1931, the German photographic industry replaced the then meaningless Scheiner numbers by a new German standard (DIN) speed. 1963Jerrard & McNeill Dict. Sci. Units 106 The Scheiner scale was devised in 1898..and was first used commercially by the Secco Film Company of Boston, Mass. in 1899. 1973Focal Dict. Photogr. Technol. 544 Scheiner speed was expressed in degrees, every increase of 3° corresponding to a doubling of the working speed. |