CHRONOTOMOGRAPHY: A NEW APPROACH TO HIGH SPEED FRAME RECORDING

Abstract For high speed frame recording the use of well-developed tomography methods of cross-section image reconstruction of three-dimen­ sional objects is suggested in this paper. In case of changing one of spatial coordinates z on a time coordinate t an analogue of series cross- sections images, which are perpendicular to axis z, is a series of frames with various values of t. In this case projections needed for tomo- graphic reconstruction can be realized as a set of streak records of two-dimensional images, obtained without a slit at various speeds of scanning. Analysis shows the possibilities of reconstruction the series of frames with temporal resolution approximating to that of streak recording. 1. Introduction Reconstruction tomography is a two-step process, which in optical terms can be described as follows. Consider a 3D object with a variable optical characteristic, absorption, for example (Fig. 1), which is represented by function f(x,y,z). Let's illuminate the object with the light beam, having definite direction. Decrease in intensity of the beam will be proportional to integral from the absorption function, taken along the chosen direction. Such an integral in tomography is usually called projection and the first stage is an obtaining of the set of such projections for a number of various directions of illuminating the object. As mathematical analysis shows that one can reconstruct the distribution f(x,y,z) with definite degree of accuracy while having a sufficiently great number of projections. It is usually done step by step, and finally the information is represented as a set of distribution f(x,y,zk) for various sections of object z^. One of such distributions is called as tomographic image or tomogram and the second stage is called a stage of tomogram reconstruction.