Nordmann, J.J.NordmannBeckmann, S.S.BeckmannEtzbach, K.H.K.H.EtzbachSens, R.R.SensBauer, M.M.BauerKrueger, H.H.KruegerBauer, J.J.BauerGuenzelmann, C.C.GuenzelmannHartmann, H.H.HartmannWalter, A.A.WalterFlaig, R.R.Flaig2022-03-082022-03-081998https://publica.fraunhofer.de/handle/publica/303901In electro-optical and photonic devices with a functional layer of oriented, cross-linked non-linear optical (NLO) polymer between 2 buffer layers, the polymer is a polyadduct (I) containing a NLO grouping, derived from: (a) NLO active compound(s) (II) containing hydroxyl (OH) group(s) reacting with cyanate groups; and (b) organic di- or polycyanate(s) (III). Also claimed is a method of making the devices. USE - The devices are planar waveguides, the function of which can be changed by electric potential, used in non-linear optics and optical information technology, e.g. modulators, Mach-Zehnder modulators, tuneable and switchable couplers, (tuneable) wavelength filters and polarisation modifiers. ADVANTAGE - Relaxation and hence loss of NLO activity is a problem with most polymers that have the required high second order susceptibility, which makes them unsuitable for technical devices requiring long-term stability. Relaxation after orientation is avoided or inhibited in (I) and optic al losses are small. Usually, relaxation is avoided up to temperatures above 100 deg. C and (I) are stable at temperature above 200 deg. C. Very wide variation of the optical properties is possible.de608621patent1996-19639446