A position measuring device includes a measuring standard and a scanning unit, which are arranged in a manner that allows them to move relative to each other in a measuring direction. The measuring standard includes a graduation, which is scannable by the scanning unit in order to generate positional signals. The scanning unit includes an illumination unit and a detector unit for generating positional signals, the illumination unit being able to emit light in the direction of the graduation and the detector unit being able to detect light modulated by the graduation. The detector unit includes a circuit board and a sensor unit, which is arranged as a semiconductor chip. At least two photodetectors are provided on a front side of the sensor unit facing the graduation, and the electrical connections of the sensor unit are routed to contact surfaces on its rear side by metallic vias. The sensor unit is connected via the contact surfaces to corresponding contact surfaces on the circuit board.