A coupling device includes a first coupling element having a first passage, and an end section connected to the free end of the light guide; as well as a second coupling element with a second passage for holding/fixing an intermediate section following the end section of the light guide. In one implementation, the first coupling element and the second coupling element can be detachably joined in a coupled state, where the first passage and the second passage form a common passage and/or have (or surround) a common longitudinal axis. The first passage can be configured with a funnel-shaped section that, in the coupled state, the first passage faces the second passage and widens toward the second passage. In addition, the first coupling element may be formed from ceramic material at least on its inner surface in the region of the funnel-shaped section.