Abstract: A lightweight light screen (1) that emits a low-intensity, diffused light of uniform brightness from its interior surface. The light screen covers both of a user's (2) eyes (3) when wom, thereby preventing ambient light from entering the user's eyes. The wearer of the light screen can see only the emitted light. The nature of the emitted light in combination with isolation from ambient visual stimuli provide a restful and therapeutic environment for the wearer. The light screen has two apertures (11) with shades (14, 15) that can be used uncover the apertures. The apertures are positioned with respect to each eye such that when uncovered the wearer can read or perform other short-focal-distance tasks that require eyesight while obtaining benefits from the emitted light. The combined area of the apertures is less than 5% of the light emitting area of the light screen so the user can maintain his/her sense of isolation while performing tasks and continue to derive benefit from irradiation.

Abstract: In a first feature of the invention, an optical switching element is a semi-transparent, metallic film having variable absorption and transmission depending upon whether one or two optical signals are present. The metallic film can be illuminated from opposite sides in a direction perpendicular to its plane by two optical signals or can be illuminated obliquely at the same angle of incidence from opposite sides by two optical signals. In another embodiment, the metallic film is located between two optical waveguides. In a second feature of The invention, an optical switching element is an optically active material that rotates the plane of polarization of an optical input signal in the absence of an optical control signal and rotates the plane of polarization of the optical input signal to a lesser degree in response to an optical control signal. The optical input signal and the optical control signal have .pi. radians phase difference in the optical waveguide and have the same plane of polarization.

Abstract: In a first feature of the invention, an optical switching element is a semi-transparent, metallic film having variable absorption and transmission depending upon whether one or two optical signals are present. The metallic film can be illuminated from opposite sides in a direction perpendicular to its plane by two optical signals or can be illuminated obliquely at the same angle of incidence from opposite sides by two optical signals. In another embodiment, the metallic film is located between two optical waveguides. In a second feature of the invention, an optical switching element is an optically active material that rotates the plane of polarization of an optical input signal in the absence of an optical control signal and rotates the plane of polarization of the optical input signal to a lesser degree in response to an optical control signal. The optical input signal and the optical control signal have .pi. radians phase difference in the optical waveguide and have the same plane of polarization.

Abstract: An optical communication cable includes an elongated flexible strip or tape, one or more optical fibers affixed to the tape, and an adhesive on a surface of the tape. The optical cable is utilized for interconnecting points within a building by applying the adhesive to an interior wall, ceiling, floor or partition. When a transparent tape is utilized, the optical cable is nearly invisible on a wall. The cable can include protective stands that run parallel to the optical fibers. Various fixtures are provided for interconnecting and installing the optical cable. Applicator tools for installing the optical cable on a surface are disclosed.

Abstract: Voting machine or system for both punching holes in a ballot and at the same time accumulating the votes. The ballots are fed into the machine, locked in place, and then tests are made to determine if the ballot is valid. If the ballot is valid, voting is accomplished by the user punching holes in the ballot. The punching of holes also produces storage of the vote which is thereafter accumulated in the machine after the ballot is approved by the voter. The machine also includes means to permit a voter to detect the he or she has overvoted a ballot and thus produced an invalid ballot so that a new ballot may be taken and voted.

Abstract: A screw having its head shaped to prevent its removal by unauthorized persons, characterized in that it has peripherally thereof an odd number of sides arranged symmetrically with respect to the center of the head and inclined to the axis of the screw to prevent removal of the screw by the use of pliers. The screw is removed by the use of a matching socket wrench.