An apparatus for obtaining an intraoral x-ray image from a patient, the apparatus has an x-ray source and a radio-frequency transceiver coupled to the x-ray source and energizable to transmit an interrogation signal, wherein the transceiver is in signal communication with four or more antennae. An intraoral image detector forms an image upon exposure to radiation received from the x-ray source. A radio-frequency transponder is coupled to the image detector and is configured to respond to the interrogation signal by transmitting a wireless response signal. A control logic processor is in communication with the transceiver and provides an output signal indicative of the spatial position of the image detector according to response signals received from the transponder at the four or more antennae. An indicator responds to the output signal by indicating the relative position of the image detector.
