A radio frequency identification (RFID) system having the capacity to detect conditions of alignment, wherein the system may be used with hand-held, fixed-in-place, stationary, and permanently mounted apparatus. The system includes an RF interrogator configured for use with dental x-ray, medical imaging, film, and digital radiography apparatus, and may include a multiplicity of RF transponders or interrogators. An RF interrogator, an RF transponder, and an x-ray sensitive imaging device, and its holder are configured to be critically aligned to a dental x-ray machine head apparatus, rendering repeat imaging unnecessary. The x-ray emitter may be further configured to automatically obtain a desired x-ray image or configured so that the device cannot activate and provide a radiograph until alignment with the transponder and associated x-ray sensitive imaging device has occurred.