Longitudinal resolution

Third, it makes it possible to observe on a real-time basis the evolution of the most short-lived transient of reacting particles, that is, to study the molecular dynamics of chemical reactions in a femtosecond time scale [2]. Many papers presented at the XXth Solvay Conference were devoted to this possibility of implementing one-dimensional resolution along the reaction coordinate. The time resolution At corresponds to the spatial resolution Az At(v), where (v) is the average velocity along the reaction coordinate, for example, the velocity of the reaction products. At v) 3 x 104 cm/s, the quantity At - 100 fs corresponds to a one-dimensional (longitudinal) resolution of Az - 0.3 A. 

Two-photon excitation by femtosecond NIR laser pulses can be used to obtain clear images of tissue layers as deep as 1 mm [132, 278, 279, 344, 462, 495, 534]. The efficiency of two-photon excitation depends on the square of the power density. It therefore works with noticeable efficiency only in the focus of the laser beam. With a microscope lens of high numerical aperture a lateral resolution around 300 nm and a longitudinal resolution of about 1 pm is obtained. Two-photon laser scanning microscopy has therefore become a standard technique of tissue microscopy. Two-photon laser scanning can be combined with... 

Ref 3 Thomson, R.N. 1984, "Transverse and Longitudinal Resolution of the SAFT" "Ultrasonics" January 1984 (Butterworth Press)... 

Method for multi-detector row spiral interpolation that uses all direct and complementary rays within a selectable distance from the image plane. Z-filter reconstruction allows establishment of different SSPs to trade off longitudinal resolution and image noise. 

CT detectors must provide different slice widths to adjust the optimum scan speed, longitudinal resolution and image noise for each application. With a singleslice CT detector, different collimated slice widths are obtained by pre-patient collimation of the X-ray beam. For a very elementary model of a two-slice CT detector... 

NY, turned by 90 ) in the isocenter of the scanner as a function of the pitch. Scan data have been acquired with 32x0.6-mm collimation in a 64-slice acquisition mode using the z-flying focal spot and reconstructed with the narrowest slice width (nominal 0.6mm) and a sharp body kernel. Independent of the pitch, all bar patterns up to 16 Ip/cm can be visualized. The bar patterns with 15 Ip/cm are exactly perpendicular to the z-axis, corresponding to 0.33-mm longitudinal resolution... 

Fig. 8 A laser rapid prototyping system. The writing could be accomplished either by mirror angle scanning or by moving sample stages. The former mechanism is shown here. Three major approaches were utilized to control the longitudinal resolution, a film casting, b surface regulation, and c open surface methods...

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