Results 151 to 160 of about 11,253,180 (206)
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Objectives for Image Converters and Image Intensifiers
Applied Optics, 1968The design of objectives for image tubes is discussed with consideration given to the limited resolution of the tubes, the desired resolution in the object plane, and the desired field of view. Particular attention is given to the case of maximum quantum yield for given resolution and field of view.
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The Detectivity of Intensifier Image Tubes
Applied Optics, 1966A theoretical development has been applied to intensifier image tubes which is similar to that used for ir photodetectors. In essence, a differential equation applicable to intensifier image tubes has been used to obtain exact solutions for signal and noise. These expressions account for factors such as phosphor time constant, area, frequency response,
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An image intensifier for the electron microscope
Journal of Physics E: Scientific Instruments, 1968An image intensifier system using a four-stage image intensifier optically coupled to a phosphor screen in the electron microscope is described. The system is shown to be limited by the quantum noise inherent in the electron image. The system can detect images down to 10 fA cm−2 which is at least an order of magnitude better than can be achieved by a ...
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Re image intensifiers and fluoroscopy stabilizers
The British Journal of Radiology, 1972Dr. J. L. Cole is not alone in his findings with regard to this particular combination of technical devices, which although it is of great convenience for working radiologists, brings with it a new concept, a new hazard, and a new responsibility (Cole, 1972). The concept of a constant and adequate input dose rate to the image intensifier is a perfectly
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Evaluation Of Image Intensifiers
Optical Engineering, 1982The performance of image intensifiers is rated according to their capability of detecting, recognizing, and identifying objects at low light levels. The most important characteristics limiting these capabilities are noise and imaging parameters. Noise parameters are normally expressed in signal-to-noise ratios, whereas imaging parameters are described ...
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Photoelectric Image Intensifiers
1971The basic reason for the development of photoelectronic devices is the fact that the photoelectric effect has a much higher quantum efficiency than the photographic effect. Thus, the probability that a photon will liberate a photoelectron is, under favorable conditions, as high as 0.3, whereas the probability that a similar photon will activate a grain
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1966
Publisher Summary This chapter describes various methods and techniques that developed to achieve that degree of excellence, as regards gain, resolution, and background and image quality that is necessary if the tube is to be useful in many important applications.
J.D. McGee +4 more
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Publisher Summary This chapter describes various methods and techniques that developed to achieve that degree of excellence, as regards gain, resolution, and background and image quality that is necessary if the tube is to be useful in many important applications.
J.D. McGee +4 more
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The Channeled Image Intensifier
1960Publisher Summary Since the invention of the photomultiplier, the simplest and most successful method of amplifying a weak photoelectric current has been by means of secondary electron emission. Several attempts have been made to extend this principle from single channel electron multipliers to two-dimensional arrays of many picture elements—that is,
J. Burns, M.J. Neumann
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1971
The history of intensifies cannot be divorced from the history of the signal-generating or camera tube itself. Interest in this area began shortly after the formalization of electron optics in the 1920’s. Much of this early work had as its ultimate objective the application of electron imaging to the problem of increasing the sensitivity of television ...
A. D. Schnitzler, George A. Morton
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The history of intensifies cannot be divorced from the history of the signal-generating or camera tube itself. Interest in this area began shortly after the formalization of electron optics in the 1920’s. Much of this early work had as its ultimate objective the application of electron imaging to the problem of increasing the sensitivity of television ...
A. D. Schnitzler, George A. Morton
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