Abstract: A matrix liquid crystal unit having a liquid crystal panel composed of two flexible plastic substrates and a liquid crystal material sandwiched between the flexible plastic substrates, and a flexible circuit sheet with a plurality of liquid crystal driver TAB.multidot.LSI assemblies mounted thereon are electrically connected to each other, making up a liquid crystal unit. Each of the flexible plastic substrates has a group of liquid crystal driver electrodes. Each of the liquid crystal driver TAB.multidot.LSI assemblies has a group of output terminals connected respectively to the liquid crystal driver electrodes through connection lines on the flexible circuit sheet. A connector connected to electrode terminals on the flexible circuit sheet, an interface connector to be connected to electrode terminals of an external control device, and printed wires for electrically connecting the connectors to each other, jointly make up a thin board.

Abstract: An electromagnetic absorbing element is comprised of an elongated rectangular body of dielectric material having a bottom portion attachable to an inner wall of an electromagnetically dark room, and peripheral elongated faces extending vertically from the bottom portion such that a set of the absorbing elements can be arranged in rows-and-columns on the wall. An electroconductive ink film is formed on the peripheral faces of body and has a gradually changing surface resistivity decreasing exponentially lengthwise of the peripheral face toward the bottom portion. The incident electromagnetic wave normal to the wall provided with the rows-and-columns of absorbing elements is absorbed by a lattice of the electroconductive films during the travel along the electroconductive films.

Abstract: A plurality of waveguide elements are arranged to form an electromagnetic wave absorbing lattice in opposed relation to the advancing wave surface of the incident electromagnetic wave. Each waveguide element has a front opening on the lattice receptive of a part of the incident electromagnetic wave, a rear end portion spaced rearwardly from the front opening, and an inner peripheral surface portion extending between the front opening and the rear end portion to define a cavity effective to wave-guide the received electromagnetic wave. The inner peripheral surface portion has a given electric resistivity to effect absorption of the received electromagnetic wave during the wave-guiding thereof without substantial reflection thereof.