MIRROR BODY FOR DUAL TYPE PYROELECTRIC INFRARED SENSOR

摘要

PURPOSE:To stabilize human body detection by arranging plural adjacent main bodies so that their detection zone do not adjoin to one another and a differential signal sent out by a dual element is outputted at the respective detection zones. CONSTITUTION:The dual element 10 has a 1st element 12 and a 2nd element 13 connected in series to opposite polarities so that the elements operate differentially. A sensor 9 including this sensor 10 is arranged between mirror main bodies 1-4 and a body 11 to be detected and detects converged heat rays from the main bodies 1-4 to output a differential signal. The plural main bodies 1-4 are so arranged that their detection zones 1'-4' do not adjoin to one another and the differential signal of the element 10 is outputted continuously. Signals of corresponding parts of overlap parts 14 among the zones 1'-4' cancel one another and a positive and a negative signal are outputted nearly continuously, so that the body 11 to be detected can be detected even in case of moving. Consequently, the stable human body detection is performed.