ISSN:0031-9228    

DOI:10.1063/1.2811137

出版商:AIP    

年代:1989

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2811138

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

A single atom, isolated and motionless, should be an excellent clock. It can radiate signals that are free of Doppler shifts and distortions introduced by its interactions with the environment. Just such thinking has motivated much work on ion traps, and that research is now bearing fruit: A group working at the National Institute of Standards and Technology in Boulder has measured the frequency of an ultraviolet transition in a single mercury atom with a linewidth under 180 Hz. The work was reported by James Bergquist, Frank Dietrich (now at Gsa¨nger Optoelectronik, FRG), Wayne Itano and David Wineland at the Ninth International Conference on Laser Spectroscopy, held in Bretton Woods, New Hampshire, last June. Before this recent feat, the narrowest width measured for an optical frequency had been on the order of a few kilohertz.

ISSN:0031-9228    

DOI:10.1063/1.2811139

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

The science of imaging and its applications touch all aspects of physics. The response of materials to light and other forms of radiation yields insights into some of the most fundamental properties of matter. Imaging technology also provides a means for viewing and understanding physical processes, as well as for recording and sharing the results.

ISSN:0031-9228    

DOI:10.1063/1.881179

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

Our visual system provides our principal contact with the world around us. This system, thanks to millions of years of natural development, achieved a high degree of perfection long before humans arrived on the scene. To attain such perfection, these evolutionary processes had to recognize the quantum nature of light—a remarkable accomplishment.

ISSN:0031-9228    

DOI:10.1063/1.881180

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

How does photographic film give such good images with so little exposure to light? The answer, in a word, is amplification. Light causes clusters of silver atoms to form on silver halide microcrystals in a photographic emulsion. These clusters, which may contain as few as three or four silver atoms, catalyze the reduction ofallthe silver ions in the microcrystals to which they are attached, giving a “gain” of over a billion. This is the basis for the high sensitivity and image quality of silver halide photographic film. As I will explain in this article, much is known about the physical mechanisms involved, and by using this knowledge one can improve the sensitivity and efficiency of film.

ISSN:0031-9228    

DOI:10.1063/1.881181

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

Artists and artisans in all eras and civilizations have produced color images for aesthetic and informational purposes. The desire to produce images that record visual experiences and to share those images with others seems intrinsic to human nature. Color is an important aspect of the visual experience. It is only natural that we attempt to understand it so that we may have control over the way we use it in drawings, paintings, photographs and electronic images.

ISSN:0031-9228    

DOI:10.1063/1.881182

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

Virtually everyone has used an optical microscope, if only to dissect a frog in school or to observe the life forms in a drop of pond water. The optical microscope is a powerful research tool in many areas of science, such as biology, geology, medicine and, more recently, semiconductor metrology. As the need to visualize submicron structures has become more pressing, several new types of microscopes have been developed—for example, the confocal scanning optical microscope, the scanning acoustic, the scanning electron and the scanning tunneling microscopes.

ISSN:0031-9228    

DOI:10.1063/1.881183

出版商:AIP    

年代:1989

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2811140

出版商:AIP    

年代:1989

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2811141

出版商:AIP    

年代:1989

数据来源: AIP