A durable tympanic thermometer that resists damage from a drop comprises an IR thermometer probe having a reinforced speculum for reception within a human ear near the tympanum, a metal brick holding the probe to the body of the infrared thermometer, a barrel within the speculum acting as an infrared waveguide, an insulating and shock absorbing seal surrounding the barrel, a window within the barrel remote from the end of the speculum nearest the tympanum, a thermometer housing, an infrared responsive sensor, and electrical components to translate and display a sensor-generated signal into a visible temperature reading.