A capacitive imaging sensor device includes a sensor substrate. A first set of sensor electrodes is disposed on a first surface of the sensor substrate, substantially in parallel with a first axis, and with at least two of its sensor electrodes extending for different lengths along the first axis. A second set of sensor electrodes is disposed on the first surface, substantially in parallel with the first axis, and in a common single layer with the first set. A processing system is coupled with the first and second sets and configured for: measuring a first capacitive coupling between a first sensor electrode of the first set and a sensor electrode of the second set; measuring a second capacitive coupling between a second sensor electrode of the first set and the sensor electrode of the second set; and determining a capacitance image using the first and second measurements of capacitive coupling.