Abstract: An optical switch for controllably switching an interface between a reflective state in which incident light undergoes total internal reflection and a non-reflective state in which total internal reflection is prevented. In one such switch a cell contains a fluid. One side of the cell forms the light incident interface. A membrane is suspended in the fluid. One pair of electrodes is applied to opposite sides of the membrane. Another electrode pair is applied to the cell's interface side and to the cell's opposite side. A variable voltage potential is applied between selected ones of the electrodes. Application of the voltage potential between selected ones of the membrane and cell electrodes moves the membrane into optical contact with the interface, producing the non-reflective state. Application of the voltage potential between other selected ones of the membrane and cell electrodes moves the membrane away from optical contact with the interface, producing the reflective state.

Abstract: An optical switch for controllably switching an interface between a reflective state in which incident light undergoes total internal reflection and a non-reflective state in which total internal reflection is prevented. In one such switch an elastomeric dielectric has a stiffened surface portion. A separator positioned between the interface and the stiffened surface portion maintains a gap there-between. A voltage source applies a variable voltage potential between electrodes on the interface and stiffened surface portion respectively. The applied voltage potential moves the stiffened surface portion into optical contact with the interface, producing the non-reflective state. In the absence of a voltage potential the separator moves the stiffened surface portion away from optical contact with the interface, producing the reflective state. In another such switch a cell contains a fluid. One side of the cell forms the light incident interface. A membrane is suspended in the fluid.

Abstract: Charged particles suspended in a medium such as Fluorinert™ Electronic Liquid are used to electrophoretically control total internal reflection (TIR) at a retro-reflective surface formed on a high refractive index material. Prismatic structures redirect ambient light from an overhead light source toward a display image and then from the image to the region in front of the image, yielding a high contrast reflective display. A transparent planar waveguide front lights the display with sequential flashes of red, blue and green light to generate a full color display. TIR can also be controlled at retro-reflective surfaces by means of a vapor-liquid phase transition, or by changing the absorption coefficient of a material using electrical, chemical and/or electrochemical methods.

Abstract: Apparatus for controlling an image display device having at least one element with a reflective state in which incident light undergoes total internal reflection and a non-reflective state in which the total internal reflection is prevented. A member is positioned adjacent the element for deformation of the member between a first position in which a gap remains between the member and the element and a second position in which the member is in optical contact with the element. The apparatus incorporates a support structure having one or more display chambers. Each display chamber contains one of the elements and members aforesaid. A first aperture is provided in the support structure for air communication between the display chamber and a second chamber provided in the support structure.

Abstract: A display device and method in which electrophoresis and/or dual prismatic surfaces are used to controllably frustrate total internal reflection at an interface between materials having different refractive indices. In one embodiment, an array of solid dielectric light fibers is surrounded by an electrophoretic medium such as acetonitrile. In the absence of electrophoretic activity, the fibers totally internally reflect light which passes into the fibers, and a reflector returns the light for diffuse emission through the fibers ends. If the fibers are subjected to electrophoretic activity their TIR capability is frustrated. A second embodiment redirects light through two prismatic surfaces in a manner which permits the TIR phenomenon to occur and to be controlled at a flat surface. A third embodiment uses both electrophoresis and dual prismatic surfaces to achieve gapless control of the TIR phenomenon at a flat surface.

Abstract: A method and apparatus for facilitating controllable switching an interface between a reflective state in which light incident upon the interface undergoes total internal reflection, and a non-reflective state in which total internal reflection is prevented at the interface. The apparatus incorporates a member (preferably an elastomer) which is deformable with respect to the interface. The member's Young's Modulus in portions of the member adjacent the interface is substantially greater (i.e. stiffer) than the member's Young's Modulus in portions of the member away from the interface. The stiffened portion of the member adjacent the interface may be in the form of a microstructure. A pair of electrodes coupled to a voltage source can be provided to controllably deform the member into optical contact with the interface, within a continuously variable range of optical contact values, to produce the non-reflective state in selectably varying degrees.

Abstract: A method of installing a floor fixture includes the step of providing a support structure for stabilizing the floor fixture relative to a floor foundation at an installation location. The method proceeds by coupling the floor fixture to a drainpipe at the installation location before a concrete floor is poured, stabilizing the floor fixture with the support structure, and pouring a concrete floor on the floor foundation while the support structure stabilizes the floor fixture. An apparatus for stabilizing a floor fixture includes a plate for coupling the body of the floor fixture to a plurality of legs extending to the floor foundation. The plate has a central opening such that the plate can be placed over the body of the floor fixture to a horizontal position in which the body of the floor fixture extends through the central opening.