Abstract: A liquid crystal display screen which includes a first transparent plate covered with an electrode array and a second transparent plate covered with a counter-electrode. A liquid crystal film is inserted between the first and second plates. Further, either of the first or second transparent plates is covered with a material coating which diffuses ambient light with a brightness which exceeds a brightness of the liquid crystal film in the absence of excitation. This coating may take the form of a metal, a white mineral pigment or a polymer film which contains surface microcracks. Such a liquid crystal display screen as in the present invention may find particular applications to terminals, computers, pocket calculators, etc.

Abstract: The invention relates to a process for manufacturing a monomode cylindrical optical waveguide made of a polymer and endowed with electrooptic properties.According to the invention, the manufacturing process comprises the following steps:producing a cylindrical core rod (11) by polymerization of a mixture comprising a core polymer and an electrooptically active organic substance,forming a first preform (10 ) by coating the core rod (11) by means of an optical cladding (12) formed by a cladding polymer,fitting said first preform (10) into a first jacket (20) constituted by a jacket polymer,producing a second preform (30) by drawing the first jacket (20),fitting the second preform (30) into a second jacket (40) made of a jacket polymer,producing means (41, 42, 43, 44) for positioning electrodes for excitation of the active substance,fiber drawing the second jacket (40) until the core diameter (d.sub.