The invention comprises a light curing device with a light source (30) and a light guiding device, in particular a light guiding rod (18) with a light entry surface (31) that extends next to the light source (30) if regarded in the emission direction of the light source (30), and with at least one sensor (36) that is arranged next to the light entry surface (31), and with a control device (32) that is arranged within a handpiece (14) of the light curing device (10). The light curing device (10) further comprises a base station (12) of the light curing device (10). The base station (12) is provided with a second light source (24) and a second light sensor (26) for the bidirectional optical communication with the handpiece (14), which bidirectional communication takes place through the light guiding device (light guiding rod), in particular in the frequency range of visible light or UV light and in particular in a modulated manner.