Showing papers on "Point spread function published in 1971"

The Influence of Random Wavefront Errors on the Imaging Characteristics of an Optical System

Abstract: The influence of random wavefront errors on the transfer function and point spread function of an optical system is studied theoretically. The stochastic part of the aberration function is assumed to be Gaussian and spatially stationary (although the requirement of stationarity is relaxed in § 5). The stochastic transformation from wavefront to transfer function is non-linear. The consequences of this non-linear transformation are two-fold: first, the statistics of the transfer function are non-Gaussian, second, the transfer function is non-stationary. (The same statements hold for the point spread function.) Therefore the characterization of these processes requires an infinite number of averaged products (moments), not just the first two if the processes were Gaussian. These averaged products are obtained in the form of multiple integrals involving the characteristic function of the wavefront and are suitable for calculation on a high speed computer. Some numerical results for the mean of both processes...

Motion blurring with decaying detector response.

Abstract: The spread function and optical transfer function associated with image motion relative to the recording medium are derived and generalized to cover media whose response changes with time. Specific expressions are derived for an exponentially decaying response and three types of image motion: linear, sinusoidal, and random walk. An expression for the blurring in flying spot scanners using cathode ray tubes, caused by the finite decay time of the phosphor, is also derived.

Experimental Demonstration of Optical Sectioning by Spatial Filtering and Its Possible Use in Transmission of Three Dimensional Pictures

Abstract: A method of spatial filtering which allows one to obtain optical cross sections of a three-dimensional object is demonstrated. The essence of the method is to photograph the object, which is illuminated by a fine pattern of light, with a camera of limited depth of field. The fine pattern appears in focus on the photographic negative of a selected cross section of the object while the foreground and background parts of the object are blurred. The photographic transparency is then placed in a standard spatial filtering setup, and the desired cross section thus obtained. The optical sectioning technique for generating three-dimensional images will then be compared according to information density with holographic and fly’s eye lenslet methods.

Surface deviations and imaging performance.

Abstract: The wave optical imaging performance of a telescope system is determined for different wavefront deviations. The point spread function, the radial energy integral in the point image, and modulation transfer functions are derived for four different magnitudes of the wavefront deviations. A feasible optimum surface precision of the imaging surfaces can be assessed.