Abstract: A marking projector, in particular a building projector, comprising at least one light generating device and at least one light coupling-out device for coupling at least a part of the light generated by the at least one light generating device out of the marking projector, wherein the at least one light coupling-out device is light-conductingly connected to the at least one light generating device by way of at least one beam path, wherein at least a part of the at least one beam path between the at least one light generating device and the at least one light coupling-out device extends through a fluid or gel-like light guide which is hardened on the surface of an areal substrate.