Abstract: In a method of fabrication of non-linear control elements for a flat display screen of the liquid crystal type, successive layers of n.sup.30 doped amorphous semiconductor, of undoped amorphous semiconductor and of metal are deposited on a substrate, whereupon the control elements are formed by masking and etching. The flanks of the control elements are then isolated, whereupon the electrodes and control leads are formed by deposition and etching.

Abstract: The invention relates to a display using a varistor as the switching element for controlling the orientation of molecules forming a liquid crystal layer. It relates to providing the connections to the elementary cells on an insulating substrate and to forming on said connections varistor contact pieces ensuring a threshold control of the said cells.

Abstract: The invention relates to a process for the manufacture of non-linear resistors (varistors) from thick-layer ceramic material, in particular on a hybrid circuit substrate, or any other device requiring that a predetermined temperature should not be exceeded during its manufacture.According to the invention, after crushing a ceramic material in order to obtain a very fine powder of varistor material, a powder is produced of conductive or semiconductive material able to assume the pasty state at a temperature lower than 850.degree. C. and a binder is incorporated therein to obtain a screen printing paste. The layer deposited by screen printing on a substrate such as glass, is dried and then heat treated so as to assure cohesion of the layer. This layer is either inserted between a previously deposited electrode and another electrode, or covered by two separate electrodes. The invention is particularly applicable to matrix access display screens.