Trailer coupling with an optical sensor

The tow hitch (10) has a sensor arrangement (30) with an optical sensor (31) for detecting an angular position of a traction coupler (16) of a trailer relative to a coupling body support. The sensor has a light detection area (37) for detecting light (39) reflected by the coupler. The arrangement has a signaling unit for producing an angular signal based on a measuring signal, where the angular signal indicates the angular position of the coupler, and the measuring signal is produced by the sensor based on the reflected light. An independent claim is also included for a traction coupler comprising a retainer for attaching the traction coupler at a coupling body of a tow hitch.