Television Resolution as a Function of Line Structures

A labor-saving method is developed for obtaining complex wave shapes by means of evaluating integrals. This method is applied to the problem of square-wave pulse shapes containing large numbers (not infinite) of harmonic components. The method is applicable for any value of cutoff frequency, expressing this value in terms of electrical degrees. A theory of "aperture processes" is developed by mathematical induction, and it is shown that the finite width of a pulse (line structure of an image) is mathematically equivalent to the pulse width obtained from an image of infinite detail scanned by a finite aperture. The finiteness of the pulse width in either case, constitutes in itself an aperture process. An approximate rule of thumb is given for defining the resolution of an image, in terms of the lines-of-resolution involved in each process imposed upon it during optical-electrical conversions. This is applicable to discussions conceming the effect of quality in the televised subject as it affects quality in the received image: as, for example, concerning the relative merits of 16- and 35-millimeter film.