An optical device including a primary fan-out waveguide; at least one secondary fan-out waveguide; a fan-out optical coupler for coupling a light beam between the primary fan-out waveguide and the secondary fan-out waveguide; at least one bus waveguide associated with the at least one secondary fan-out waveguide and different from each secondary fan-out waveguide; and a reflecting and coupling structure connecting the secondary fan-out waveguide and the bus waveguide.