A proposal for a new lower hybrid wave launcher for the current drive in future large thermonuclear facilities operating in the 10 GHz frequency range is given. The principle of the quasi-optical grill is combined with the concepts of the hyperguide and the multijunction grill. As an example, a six rod structure mounted in an oversized waveguide and irradiated by an oblique plane wave emerging in the form of a higher mode from an auxiliary oversized waveguide is optimized. The rods of the optimum structure have the elongated form of the cross-section with a resonant length (in the direction of wave propagation) equal to a multiple of the half wavelength of the fundamental mode of the hyperguide. This row of rods forms a multijunction grill with the zero, built-in, phase shift between waveguides. The second row of rods supporting the constructive superposition of the incident and doubly reflected waves enhances the efficiency of the structure. The optimum structure has a power spectrum with two narrow peaks (the main N|| = -2.15 peak and the parasitic N|| = 3.15 peak), a low power reflection (Rtot = 18%), a high coupled power directivity (δCP = 68%), a reasonable N||-weighted directivity (|δCDw| = 36%) and a peaking factor on the electric field equal to 3. On the basis of the optimization it is possible to design the parameters of a large structure with tens of rods. The number of construction elements in this structure can be reduced 20 times in comparison with the standard multijunction array