Infrared sensing device and method of sensing human body by the same

摘要

An infrared sensing device includes: a condensing lens 11 for gathering an infrared ray from a human body; a guide unit 12 for dividing the field of view of a room to be monitored into a plurality of lateral and vertical zones and for guiding the infrared ray to a part of an infrared sensor unit corresponding to its direction; a housing 13 for enclosing the condensing lens and guide unit to preclude dispersion of the incident infrared ray; the infrared sensor unit 14 for sensing infrared ray(s) in one or more of the zones; and a signal processing 15 unit for amplifying an output signal of the infrared sensor unit, converting the amplified signal into a digital signal, and analysing the digital signal. The sensor unit 14 has two far-field sensing elements 17a,b and a near-field sensing element 17c. The signal analysis routine is described.