Showing papers on "Aerial image published in 1973"

Increasing the Dynamic Range of Coherent Optical Filters by Means of Modulating Gratings.

Abstract: We report on a new method for increasing the linear dynamic range of coherent-optical spatial filters, with special reference to holographic image-deblurring filters. In the filter-generating step, a transmission grating is placed in contact with the transparency representing the spread function of the blur. The spectrum of the spread function then appears in a series of equally spaced islands of different intensities, each occupying a different region of the nonlinear characteristic of the recording medium. Each spatial frequency can then be properly exposed somewhere on the filter, even with a film of limited dynamic range. In the image -processing step, the grating is superposed on the blurred image, the spectrum of which then falls on all the islands of the filter. In this way, the filtering operation is done in parallel channels, each with a different nonlinear characteristic. The channels are combined in the output plane by superposing a grating on the filtered aerial image and viewing this plane through an optical system that does not resolve the grating. Theory, computer simulations, and experimental results are presented. The results show in particular that a good transfer function can be achieved with a hologram-only filter.

Parallax free viewer

Abstract: A novel viewing arrangement for a reflex camera includes a concave mirror that forms an image of a focusing screen through a window in a plane mirror that folds the reflex camera''s optical path. The concave mirror is conaxial with the center of an echelon mirror formed on the surface of, and concentric with, the focusing screen. It forms an aerial image of the focusing screen and the real image formed thereon by the camera''s objective lens. An eye lens magnifies the aerial image for a user who views the scene through it from an eye station. One embodiment utilizes an ellipsoidal reflecting surface on the concave mirror. Another embodiment utilizes a parabolic reflecting surface on the concave mirror and a plane mirror to erect the image and direct it toward the eye lens.

Applying art work to motion picture film

Abstract: Titles, identifying indicia, figures, and other art work are superimposed on a motion picture film having a live action background by a modified aerial image cinematographic technique in which the art work is coated with a fluorescent pigment, interposed in the aerial image, back lighted, and photographed together with the image. The fluorescent pigment coating permits back lighting at a relatively low light intensity at which adequate color saturation of the film is achieved without producing corona, halo, burning and other adverse effects.