Abstract: Perfluorinated polyimides (and co-polyimide) compositions, particularly films are disclosed, comprising at least 50 mole percent of a polymeric repeat unit derived from contacting 3,3?,4,4?-biphenyltetracarboxylic dianhydride (BDPA) and 2,2?-bis(trifluoromethyl) benzidine (TFMB) monomers. The perfluorinated polyimide (and co-polyimide) films of the invention have an in-plane coefficient of thermal expansion (CTE) between ?5 and +20 ppm/° C. and a average light transmittance percent of from about 65.0 to about 99.0 (on a 75-micron thick film basis). The films of the present invention were converted to a polyimide using a chemical conversion method instead of typically employed thermal conversion step thus yielding these desirable properties. The films of the present invention can be an excellent substrate in an optical display device and can be used to replace rigid glass substrates. Finally, the polyimide films of the invention can also be used to manufacture flexible display devices (e.g.

Abstract: Perfluorinated polyimides (and co-polyimide) compositions, particularly films are disclosed, comprising at least 50 mole percent of a polymeric repeat unit derived from contacting 3,3?,4,4?-biphenyltetracarboxylic dianhydride (BDPA) and 2,2?-bis(trifluoromethyl) benzidine (TFMB) monomers. The perfluorinated polyimide (and co-polyimide) films of the invention have an in-plane coefficient of thermal expansion (CTE) between ?5 and +20 ppm/° C. and a average light transmittance percent of from about 65.0 to about 99.0 (on a 75-micron thick film basis). The films of the present invention were converted to a polyimide using a chemical conversion method instead of typically employed thermal conversion step thus yielding these desirable properties. The films of the present invention can be an excellent substrate in an optical display device and can be used to replace rigid glass substrates. Finally, the polyimide films of the invention can also be used to manufacture flexible display devices (e.g.

Abstract: The present invention relates to a method of manufacturing an optical fiber by carrying out one or more chemical vapor deposition reactions in a substrate tube, with the optical fiber exhibiting a low sensitivity to the hydrogen-induced attenuation losses at a transmission wavelength of 1550 nm. The present invention furthermore relates to an optical fiber comprising a cladding layer and a light-conducting core, which fiber has been obtained by using the present method.

Abstract: A preform for manufacturing an optical fibre or an optical fiber, where the variation in the refractive index contrast of the preform does not exceed an absolute value of 2%, measured for a preform having a length of at least 60 cm, or the deviation of the preform in relation to the average value of the profile parameter ? does not exceed an absolute value of 0.03, measured for a preform having a length of at least 80 cm. The optical fibre has a deviation from the average value of the profile shape parameter ? of maximally about 0.03.

Abstract: The present invention relates to a method for manufacturing a preform for optical fibres, wherein deposition of glass-forming compounds on the substrate takes place. The present invention furthermore relates to a method for manufacturing optical fibres, wherein one end of a solid preform is heated, after which an optical fibre is drawn from said heated end.

Abstract: The present invention relates to a method for manufacturing a bar-shaped preform, which method comprises the following steps; i) supplying one or more reactive gases, at least one comprising fluorine which may or may not be doped, to the interior of a substrate tube. ii) carrying out a deposition reaction of gases from step i) in said susbstrate tube so as to obtain one or more glass layers on the interior or the substrate tube, and iii) contracting the substrate tube from ii) while heating said tube so as to obtain the massive, bar-shaped preform, characterized in that the amount of fluorine compound that is supplied to the interior of the substrate tube in accordance with step 1) is increased by at least 10% at the end of the deposition of glass layers on the inner side of the substrate in accordance with step ii), after which the substrate tube is subjected to the heat treatment under conditions such that diffusion of the additionally incorporated fluorine from the deposited glass layers will occur.

Abstract: The present invention relates to a method of manufacturing an optical fibre, which method comprises the following steps: i) providing a hollow substrate tube, ii) passing doped or undoped reactive, glass-forming gases through the interior of the hollow substrate tube, iii) creating such conditions in the interior of the hollow substrate tube that deposition of glass layers onto the interior of the hollow substrate tube takes place, wherein a non-isothermal plasma is reciprocated between two reversal points along the substrate tube, wherein the velocity of movement of the plasma decreases to zero at each reversal point, iv) collapsing the substrate tube thus obtained so as to form a solid preform, and v) drawing an optical fibre from said solid preform. In addition to that, the present invention relates to a preform for manufacturing an optical fibre, as well as to an optical fibre.