The invention relates to an optical device (1) for a motor vehicle headlight, said device comprising the following: a primary optical element (100) having a main body (101) and a plurality of optical waveguide bodies (110) having a light-receiving surface (120) and a light-emitting surface (130); a holder (200) on which the primary optical element (100) is arranged, wherein the optical waveguide bodies (110) penetrate the holder (200) via an opening region (201) of the holder; and a covering element (300) which is arranged on the holder (200) and comprises openings (310) which receive the optical waveguide bodies (110), wherein the covering element (300) can be connected to the holder by means of a projection (420) comprising an engaging section (421) and an end section (422) and a guide recess (410) having a first region (411) and a second region (412), said second region extending in a slip-on direction (X), wherein the projection (420) can be inserted in the first region (411) such that the second region (412) can be slipped onto the engaging section (421) by means of the movement of the covering element (300) in the slip-on direction (X).