Abstract: An improved puzzle of the type in which a target image is applied to the edge of a stack of slats. The slats are shuffled and then reassembled by the user. In the improvement, the strip of target image that is associated with the edge of each slat is extended beyond the edge, along the surface of the slat, allowing the user to more readily perceive the puzzle pattern, particularly on relatively thin slats. The improvement also allows economic manufacture from inexpensive materials by ordinary printing techniques. Slats can be printed flat, then formed by folding.

Abstract: An improved puzzle of the type in which a target image is applied to the edge of a stack of slats. The slats are shuffled and then reassembled by the user. In the improvement, the strip of target image that is associated with the edge of each slat is extended beyond the edge, along the surface of the slat, allowing the user to more readily perceive the puzzle pattern, particularly on relatively thin slats. The improvement also allows economic manufacture from inexpensive materials by ordinary printing techniques. Slats can be printed flat, then formed by folding.

Abstract: A perforated convex mirror with a non-specular concave face, being partially transparent and partially reflective, acts like a lightly silvered mirror, but it's concave face does not focus collimated light.

Abstract: An apparatus that appears to actively track the position of a viewer by producing a red circle about the viewer's image, seen in a security mirror. The red circle appears to translate and rotate to track the viewer's position. Rotational tracking operates independently of the mirror.

Abstract: A decorative screen, particularly for use in window treatments, interior decoration, and the like, which can be easily customized to complement any decor. The decorative screen uses ambient light, diffusers, and grids to process a crude design. The result is a pleasing mosaic of elements. Just as in a typical tile mosaic, the hue, saturation, and brightness of each element is consistent across that element.

Abstract: A variable pitch screw is manufactured by twisting a prepared blank to the desired shape. The blank varies along its length such that it naturally twists to the desired shape.

Abstract: A method and apparatus to isolate the video image of an object, usually a human being, from its background for use in forming a composite image. The viewer's image, with its background, is captured in both visible light and infra-red. In the preferred embodiment, the visible light image is modified by replacing, from an independent visible image source, that area corresponding to the cold (non-viewer) areas of the infra-red image.

Abstract: Constant balance of a varying load, particularly a window shade or blind, is maintained by providing a lifting force, preferably from a spring, through a mediating mechanism comprising a variable pitch screw assembly, such that the mechanical advantage of the mediating mechanism changes to allow the continuously decreasing spring force to apply an appropriate lifting force at all times. A variable pitch screw thread is formed as grooves in a cylindrical blank. The grooves are engaged by pins in a nut which thereby accomodates the variable pitch of the screw. A compact blind tilting mechanism is also incorporated. The capacity of the mechanism can be increased by linking several screw assemblies.

Abstract: Constant balance of a varying load, particularly a window shade or blind, is maintained by providing a lifting force, preferably from a spring, through a mediating mechanism including a variable pitch screw arrangement, such that the mechanical advantage of the mediating mechanism changes to allow the continuously decreasing spring force to apply an appropriate lifting force at all times. The variable pitch screw preferably takes the form of a twisted bar.

Abstract: In an illusion apparatus for self viewing, a specific element (usually a dark region) of a display is positioned on or about the line connecting the viewer and the center of curvature of a partially reflective partially transparent, convex mirror. The specific element thus appears in a relatively constant relationship to the viewer's image even as the viewer changes position in relation to the mirror and display.

Abstract: The present invention is directed toward a light concentration and collimation device including a tapered body concentrator and a curved, preferably parabolic, reflective collimator combined in a unit such that the apex of the tapered body extends into the reflective collimator through its apex. The concentrator is preferably hollow with a reflective inner surface to funnel light from the base to the apex where an aperture allows the concentrated light to enter the collimator proximate to its focus. The light is then reflected from the inner surface of the collimator to form a beam of collimated light. The concentration and collimation device is particularly useful in visual display apparatus and may be combined with a spectral peak light source and a spectral distributor to produce individual collimated beams of light at specific wavelengths.

Abstract: By a new configuration which more efficiently controls illumination, it is possible to make a mirror dissolve illusion which uses less power than those previously known in the art. A reflector and lamp assembly is provided in front of a partially reflective and partially transparent (one-way) mirror to direct light to a viewer via the one-way mirror. The technique includes use of a backlit wall pattern and a reflective floor surface along with a mirror of reduced density.