| 摘要 |
PURPOSE: An infrared sensor is provided to detect infrared rays emitted by an additional projector or a projector installed in a different boundary area by detecting the infrared rays emitted by an additional projector as well as a main projector. CONSTITUTION: An infrared sensor consists of a projector(100) and a receiver(200) sharing specific ID(Identification) data. If infrared rays including ID data are emitted from the projector, the receiver receives the infrared rays and compares the ID data with the received amount of rays to detect interference by approaching of an individual or object, or by a projector of a different boundary area. The projector includes a pulse oscillator(110) generating a carrier for producing infrared rays and ID data, an ID data generator(120) generating ID data periodically to identify projector signals according to the carrier, and a projection unit(130) emitting infrared rays including the ID data to outside. The ID data generator outputs ID data periodically. Herein, the period of generating the ID data is larger than one of the carrier generated from the pulse oscillator. The receiver has a receiving unit(210) receiving infrared rays, an amplifier(220) amplifying the signals of the receiving unit, an isolation decision unit(230) deciding isolation of rays according to the amount of rays included in the output signals of the amplifier, a comparator(240) outputting an alarm signal if the isolation time is longer than predetermined value, an error waveform decision unit(260) outputting an alarm signal if error waveform is interpolated into the received waveform, and an alarming device(250) operated according to the alarm signals. The interference between near infrared sensors is prevented. |
