The present invention is directed to a method and apparatus for displaying a virtual image and for providing control over the "alpha channel" or transparency of the virtual image. The present invention uses a beam splitter to provide a virtual image to a viewer. Behind the beam splitter is a liquid crystal region for controlling the transparency of the virtual image. Behind the liquid crystal region is a background image. Control of the liquid crystal region is coordinated with control of the virtual image so as to make transparency and opacity of the liquid crystal region follow the portions of the virtual image that are intended to be transparent and opaque, respectively.
A visual display system for use in conjunction with a video screen connected to a computer for displaying images of an object taken at successive angles. The system includes a platform having a circular body with an opening, above the screen and an annular turntable supported by the body for turning. A sensor connected to the computer senses the angular position of the turntable relative to the body. The system further includes an inclined transparent glass plate located directly above the opening for reflecting an image from the screen to form a virtual image in the space above the body for viewing through the plate by an observer. The turntable is manually rotatable to control the screen to display an image of the object corresponding to the angle through which the turntable is turned, thereby turning the virtual image for viewing of the object along different directions.
A printbar assembly comprised of an array of light emitters, and array of gradient index lenses, and a light control film. The light control film, which is comprised of a plurality of microlouvers, is disposed such that it limits the angle at which light from the light emitters can enter the gradient index lenses. The light control film increases the depth of focus of the gradient index lens array without significantly reducing the effective radiometric efficiency.
A display system or monitor arrangement for stereoscopic displaying of images includes a pair of displays for providing respective left eye and right eye images and arranged in perpendicular intersecting planes, a beam splitter for combining the images from the displays in a common light path, and a means to discriminate between respective images to present the respective left and right eye images to the eyes of a viewer for viewing. Image discriminating functions may be obtained using plane polarized light characteristics and/or circular polarized light characteristics. A package arrangement retains the display a system components for storage or use; and a cubical mount structure may provide alignment and positioning of respective parts of the display system. Display methods for displaying stereoscopic images in a common light path are included.
A liquid crystal panel displays an image, while a lens projects, as a virtual image, an image displayed by the liquid crystal panel. A control system controls either the liquid crystal panel or the lens so as to periodically effect a changing of the position of the virtual image, each changing occurring over a predetermined time period. The control can be accomplished by changing the position of the liquid crystal panel or of the lens along an optical axis at a speed of less than 0.1 mm/sec so as to avoid burdening the eye of the observer. The motion can be at a uniform speed through most of the range of the motion, while permitting a slowing down to a stop at each end of the range and then an acceleration to the uniform speed in the opposite direction. A rest period (i.e., a full stop for a period of time) can be provided at one or both ends of the motion range, either for each cycle of motion or after the occurrence of a plurality of such cycles. When used in a situation in which the size of the viewed image is of particular importance, the size of the display region can be changed so that the apparent image size remains constant with a change in the position of liquid crystal panel.
A thin stereoscopic display which enables plural persons to simultaneously observe stereoscopic images includes a color liquid crystal plate for displaying stereo-pairs composed of left and right eye perspectives in time-interlaced manner, a monochrome liquid crystal TV display disposed behind the color liquid crystal plate for displaying binary and inverted binary images a right or left half of the face of each observer so as to be synchronized with the time-interlaced display of the color liquid crystal plate, and an arrayed convex lens disposed between the color liquid crystal plate and the monochrome liquid crystal TV display so as to focus the observers' optical images on the screen of the monochrome liquid crystal TV display in geometrical agreement with the observers' face images displayed thereby. The arrayed convex lens distributes light emitted from the binary and inverted binary images of the half of the face of each observer to the left and right eyes of each observer through the color liquid crystal plate, respectively, whereby the left and right eye perspectives of the stereo-pairs displayed by the liquid crystal plate reach the left and right eyes of each observer, respectively.