Abstract: A mouldable product such as a pad which can be selectively transformed between pliable and rigid states is formed of a sealed plastic container which houses a metastable compound such as sodium acetate tri-hydrate, a trigger device for initiating the nucleating process in the compound to render it rigid, and a reinforcing open micro-porous material. The material may be fibrous, e.g., cotton, and stabilizes the product in its rigid state for a comparatively long time.

Abstract: An integrated optic component comprises a substrate (10) carrying a layer (11) of polymeric material which has an aliphatic or aromatic polymer backbone with bonded sidegroups exhibiting hyperpolarizability. The layer (11) shows a refractive index pattern induced by irradiation with wavelengths within the electronic absorption bands of the sidegroups and within the range of about 230 to 650 nm. The component may be poled so as to be an active component and may be in the form of a ridge guide. Typical sidegroups comprise 4'-amino or 4'-oxy substituted 4-nitrostilbene moieties, or 4'-amino substituted 4-cyanostilbene moieties, or N-substituted 1-(4-aminophenyl)-4-(4-nitrophenyl) buta-1,3-diene moieties.

Abstract: An integrated optic component comprises a substrate (10) carrying a layer (11) of polymeric material which has an aliphatic or aromatic polymer backbone with bonded sidegroups exhibiting hyperpolarizability. The layer (11) shows a refractive index pattern induced by irradiation with wavelengths within the electronic absorption bands of the sidegroups and within the range of about 230 to 650 nm. The component may be poled so as to be an active component and may be in the form of a ridge guide. Typical sidegroups comprise 4'-amino or 4'-oxy substituted 4-nitrostilbene moieties, or 4'-amino substituted 4-cyanostilbene moieties, or N-substituted 1-(4-aminophenyl)-4-(4-nitrophenyl) buta-1, 3-diene moieties.

Abstract: In a strain sensing system in which a strained grating is illuminated with a pair of beams chosen from three possible beams to sense strain in two dimensions, an arrangement is disclosed of two beam splitters, as least one plane mirror, and three tilted mirrors, all fixed to a support plate and which can supply the three required illuminating beams.