Position measuring system having - a graduation carrier that has a measurement graduation (15, 16, 17) that reflects electromagnetic radiation and extends along a measurement direction (x) on a first surface and - a scanning head for scanning the measurement graduation (15, 16, 17), said scanning head having a transmitter for emitting electromagnetic radiation onto the measurement graduation (15, 16, 17) and a receiver (26, 27) for receiving radiation reflected by the measurement graduation (15, 16, 17), wherein the transmitter and the receiver are arranged on an active side of the scanning head that faces the first surface of the graduation carrier and - wherein the graduation carrier and the scanning head, as mutually separate components, form an open position measuring system such that the space between the graduation carrier and the scanning head is not sealed in relation to the surroundings and the graduation carrier and the scanning head can be moved into any relative position along the measurement direction (x), and - wherein a wraparound that can be moved together with the scanning head relative to the graduation carrier protrudes from the scanning head, said wraparound wrapping around the graduation carrier in respect of the graduation carrier in the case of an intended arrangement of the scanning head in such a way that a portion of the wraparound, referred to as protective portion, extends in front of a second surface of the graduation carrier that faces away from the first surface provided with the measurement graduation (x) and - wherein the protective portion of the wraparound lying opposite the second surface of the graduation carrier has such an extent (a) that electromagnetic radiation emitted by the transmitter when the graduation carrier is absent strikes the protective portion in order to prevent the uncontrolled emission of electromagnetic radiation emitted by the transmitter of the scanning head into the surroundings and - wherein the protective portion of the wraparound is arranged at a distance from the second surface of the graduation carrier when the graduation carrier is in its intended position in relation to the scanning head and - wherein the wraparound is embodied and arranged on the scanning head in such a way that the wraparound restricts a possible tilt of the graduation carrier in respect of the scanning head and - wherein the wraparound restricts a possible tilt of the graduation carrier from its intended position in respect of the scanning head to tilt angles ensuring that electromagnetic radiation emitted by the transmitter and reflected at the tilted graduation carrier does not emerge from the space between the scanning head and the wraparound and - characterized in that the transmitter of the scanning head is embodied for emitting laser radiation. - a graduation carrier that has a measurement graduation (15, 16, 17) that reflects electromagnetic radiation and extends along a measurement direction (x) on a first surface and - a scanning head for scanning the measurement graduation (15, 16, 17), said scanning head having a transmitter for emitting electromagnetic radiation onto the measurement graduation (15, 16, 17) and a receiver (26, 27) for receiving radiation reflected by the measurement graduation (15, 16, 17), wherein the transmitter and the receiver are arranged on an active side of the scanning head that faces the first surface of the graduation carrier and - wherein the graduation carrier and the scanning head, as mutually separate components, form an open position measuring system such that the space between the graduation carrier and the scanning head is not sealed in relation to the surroundings and the graduation carrier and the scanning head can be moved into any relative position along the measurement direction (x), and - wherein a wraparound that can be moved together with the scanning head relative to the graduation carrier protrudes from the scanning head, said wraparound wrapping around the graduation carrier in respect of the graduation carrier in the case of an intended arrangement of the scanning head in such a way that a portion of the wraparound, referred to as protective portion, extends in front of a second surface of the graduation carrier that faces away from the first surface provided with the measurement graduation (x) and - wherein the protective portion of the wraparound lying opposite the second surface of the graduation carrier has such an extent (a) that electromagnetic radiation emitted by the transmitter when the graduation carrier is absent strikes the protective portion in order to prevent the uncontrolled emission of electromagnetic radiation emitted by the transmitter of the scanning head into the surroundings and - wherein the protective portion of the wraparound is arranged at a distance from the second surface of the graduation carrier when the graduation carrier is in its intended position in relation to the scanning head and - wherein the wraparound is embodied and arranged on the scanning head in such a way that the wraparound restricts a possible tilt of the graduation carrier in respect of the scanning head and - wherein the wraparound restricts a possible tilt of the graduation carrier from its intended position in respect of the scanning head to tilt angles ensuring that electromagnetic radiation emitted by the transmitter and reflected at the tilted graduation carrier does not emerge from the space between the scanning head and the wraparound and - characterized in that