Patent attributes
A passenger detection device that determines whether a passenger sits in a passenger seat or backseat, and if YES, determines whether the passenger is an adult or a child, and whether the passenger is sitting in a normal attitude. A pair of thermopile sensors 13 and 14 are disposed on a dashboard 11 at a predetermined distance from each other in a horizontal direction. The pair of thermopile sensors 13 and 14 are disposed such that they monitor a predetermined same position P on a surface of the passenger seat 12 when a passenger 15 does not sit in a passenger seat 12. Output signal which are output from the pair of thermopile sensors 13 and 14 are subtracted by a subtraction circuit 25, an output difference signal of the pair of thermopile sensors 13 and 14 is taken out, and it is detected whether a passenger sits in the seat by this signal.