A lightguide component for illumination devices having first and second exit surfaces at opposite sides, the lightguide component including: a light-receiving portion to receive light emitted from a light source; a lightguide layer having a first principal face at the first exit surface side and a second principal face at the second exit surface side; and a light distribution controlling structure having a plurality of internal spaces. Each of the plurality of internal spaces includes a first slope to direct a portion of light propagating in the lightguide layer toward the first exit surface via total internal reflection, and a second slope at an opposite side from the first slope, and the lightguide component is configured to emit first light having a first intensity distribution through the first exit surface and to emit second light having a second intensity distribution through the second exit surface.