Infrared sensor

Discussion in 'The Projects Forum' started by ching fong kee, Jun 26, 2010.

  1. ching fong kee

    Thread Starter Member

    Jun 23, 2010
    when someone is pass through the IR transmitter and the IR receiver, is it there is no voltage will happen in that circuit??if there are no voltage, is it need use the inverter to make it got voltage?
  2. retched

    AAC Fanatic!

    Dec 5, 2009
    Do you have a particular circuit in mind? Do you have a schematic for the circuit you are thinking about?

    In general, a beam-break sensor can stay HIGH(with voltage) or LOW(without voltage) until the beam is broken when someone walks in front of the transmitter.

    Depending on the receiver, you can set it up to provide a pulse or signal that is either high or low.

    The ones I have made, use a switch to HIGH when it is interrupted.

    here is an instructable on the idea. Google 'beam break circuits' for more ideas and products.
  3. ching fong kee

    Thread Starter Member

    Jun 23, 2010
    thanks for replying..
    not really...because i not so sure the about it..
    beam break sensor is it combination of IR emitters and phototransistor?
  4. Bernard

    AAC Fanatic!

    Aug 7, 2008
    Yes. Emitter can be a steady beam or modulated into short flashes, the receiver is designed to match emitter. The modulated pair prevents spurious light interference.