2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
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1、2000 單詞, 單詞,1.1 萬英字符, 萬英字符,3570 漢字 漢字出處: 出處:Johnston S F. Absorbing New Subjects: Holography as an Analog of Photography[J]. Physics in Perspective, 2006, 8(2):164-188.Absorbing New Subjects: Holography as an Analog of

2、PhotographySean F. JohnstonI discuss the early history of holography and explore how perceptions, applications, and forecasts of the subject were shaped by prior experience. I focus on the work of Dennis Gabor (1900–19

3、79) in England,Yury N. Denisyuk (b. 1924) in the Soviet Union, and Emmett N. Leith (1927–2005) and Juris Upatnieks (b. 1936) in the United States. I show that the evolution of holography was simul- taneously promoted a

4、nd constrained by its identification as an analog of photography, an association that influenced its assessment by successive audiences of practitioners, entrepreneurs, and consumers. One consequence is that holograph

5、y can be seen as an example of a modern technical subject that has been shaped by cultural influences more powerfully than generally appreciated. Conversely, the understanding of this new science and technology in term

6、s of an older one helps to explain why the cultural effects of holography have been more muted than anticipated by fore- casters between the 1960s and 1990s.Key words: Dennis Gabor; Yury N. Denisyuk; Gabriel Lippmann;

7、Emmett N. Leith; Juris Upatnieks; holography; photography; stereoscopy; art; wavefront reconstruction.IntroductionThe emergence of new subjects in science and technology is seldom a neutral process in society. Historia

8、ns have long recognized that science, technology, and culture are interlinked, but generalizations about their relationships have tended to remain con- tentious because the strength and direction of their mutual influe

9、nces have been dis- puted case by case. While some work in the history of science has focused on the evo- lution of new subjects, relatively few studies have explored directly how this process is influenced by preexi

10、sting technologies.1I discuss the history of holography and photography to explore how perceptions, applications, and forecasts of new subjects can be shaped strongly by prior experience. I argue that the evolution of h

11、olography was simultaneously promoted and constrained by its identification as an analog of photography, and that this association influenced its assessment by successive audiences of practitioners, entrepreneurs, and

12、consumers. One consequence is that holography can be seen as an example of a modern technical subject that has been shaped by cultural influences more powerfully than generally appreciated. Conversely, this understand

13、ing of this new science and technology in terms of an older one helps to explain why the cultural effects of holography have been more muted than anticipated by forecasters between the 1960s and 1990s. Holography illu

14、strates how cultural predilections can transform a radically new concept into a more easily absorbed form.Dennis Gabor and the Context of MicroscopyThe term “holography” became dominant by about 1966 to describe techniq

15、ues and concepts that had been circulating for nearly two decades among a handful of To Gabor’s contemporaries, his novel concept was arcane, complex, and unpromis- ing. Sir Lawrence Bragg (1890–1971), well-known for hi

16、s early work in X-ray diffrac- tion** and now Gabor’s informal mentor, wrote to him on July 5, 1948, that “I think I am beginning to understand the principle, though it is still rather a miracle to me that it should w

17、ork.” 2 A handful of other physicists who explored wavefront reconstruction criticized Gabor’s expository style, unjustifiable optimism, and technical limitations. For example, Gordon L. Rogers (b. 1916), Gabor’s close

18、st collaborator in the field, report- ed to a colleague on September 2, 1952, that “by now several people … have taken the snags out of the original draft [of the book chapter Gabor has written], and his claims are no

19、w much more modest and reasonable. I still feel, however, that they are not very helpful, though they are no longer unsound.” 3 Similarly, Max Born (1882– 1970) had written to Gabor on February 21, 1951, that “I have re

20、ad more of your MS. And I think that your considerations are most ingenious. But I can at the same time not conceal that they always seem to me a little weird, and prickle my physical sensitivities.” Gabor’s critics d

21、efined the nature, boundaries, and problems of wavefront recon- struction by viewing it as a new form of microscopy, an imaging technique applied to microscopic objects. There are at least four explanations for this pe

22、rceptual pigeon-hol- ing: first, Gabor’s conception had begun with the problems he perceived were involved in electron microscopy; second, the hybrid system that he dubbed the “holoscope” had formal similarities to ear

23、lier concepts in the design of optical instruments, in particular,the Abbe theory of imaging in microscopes* and Bragg’s recent X-ray microscope;5 third, he had promoted wavefront reconstruction specifically to micros

24、copists in demonstrations and articles; and fourth, those who took an interest in Gabor’s work were themselves seeking to improve optical or short-wavelength microscopy. Their perspective on wavefront reconstruction th

25、us was a consequence of their disciplinary commitments and perceptions as microscopists; they viewed wavefront reconstruction with the mindset of microscopists. The content of this new subject was influenced by its pa

26、st disciplinary context.A second constraint followed from the implicit assumptions these researchers made about the boundaries of their subject. As Bragg and Born indicated above, the concept and characteristics of wav

27、efront reconstruction were alien to them. One of its miracu- lous attributes was that this two-stage imaging technique produced a three-dimension- al image. Gabor’s papers and patent emphasized that wavefront reconstru

28、ction record- ed three dimensions of a sample, yet he never mused about its application to stereo- scopic imaging.6 This was natural considering his categorization of the technique as microscopy. Thus, microscopes had

29、 associated traits that may have seemed inescapable: they are optical devices with a single optical axis, and they used an eyepiece to produce an image. These traditional physical assumptions may well have hindered cons

30、idera- tion of unfamiliar imaging geometries. An eyepiece, at the very least, foreclosed the possibility of observing an image in parallax. Gabor and other workers in wavefront reconstruction also may have sensed subl

31、iminally that the limited coherence length of their light sources confined the observed sample to microscopic dimensions. A stereo- scopic image thus was scarcely conceivable to them.The most important conclusions this

32、 band of investigators drew concerned the drawbacks of wavefront construction as based upon criteria defined by microscopy: Most saw wavefront reconstruction as fatally flawed by the so-called “twin-image prob- lem,” i

33、n which a fuzzy second (conjugate) image seemed doomed to overlap the desired image, rendering this technique unsatisfactory for any practical use. Gabor himself blamed its lack of technical and commercial success main

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