Abstract: A proximity sensing device is disclosed comprising: a radiation emitter; a radiation sensor configured to sense a reflected radiation from the radiation emitter; a memory for storing a plurality of ambient radiation level ranges and a plurality of coefficients that map onto the plurality of ambient radiation level ranges; and processing circuitry configured to compensate an output from the radiation sensor for crosstalk by subtracting from the output a measured ambient radiation level scaled by either: a coefficient selected from the plurality of coefficients; or a value derived from the plurality of coefficients. A proximity sensing method and a proximity sensing calibration method are also disclosed.