A lighting device includes at least one first light-emitting element configured to emit a first light of a first wavelength range; and a light guide having axially opposite first and second base surfaces, and a plurality of segments, each with a first light in-coupling surface formed on a lateral surface of the light guide, each of the segments configured to convert at least a part of input light into second light having a selected wavelength range. At least a portion of the first base surface includes a second light in-coupling surface and at least a portion of the second base surface includes a light out-coupling surface. The lighting device is optically coupled to the second light in-coupling surface such that the first light is coupled into the light guide, and the first light emitting element is configured to reflect at least part of the second light thereon having a wavelength within at least one of the selected wavelength ranges back into the light guide.