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Infrared Dectector Circuit

  • 09-03-2006 10:23AM
    #1
    Registered Users, Registered Users 2 Posts: 10,896 ✭✭✭✭


    I wondering if someone could help me with this. I have a timing system that consists of a set of electronic eyes. One recieves the infrared signal from the other. The thing is I want to build a circuit to put on the reciever so that when it recieves the signal a led lights up. This is so I can set them up easily.

    It would be cool if anyone could tell me what kinda component would I need to recieve the signal up to about a 150feet, and isn't affected by ambiant light.

    The rest of the circuit i pretty much can build. I guessing a simple transistor circuit would do. It's just that I don't know what to use as the IR detector.


Comments

  • Closed Accounts Posts: 296 ✭✭PDelux


    I'm not sure if IR is supposed to be used over long distances.

    For the detector, a photodiode is usually used and a couple of op-amps to amplify the signal because the signal from the photodiode will be very small. This is how modern smoke alarms work.


  • Closed Accounts Posts: 51 ✭✭david powell


    Hi,

    As the last poster said, no way an IR Transmitter ( IR LED ) & Detector would work over that range. Also I presume this would be used outdoors, there is alot of IR content in normal sun light....

    If i had to work over that range i would use some sort of laser ( a simple laser pointer might work well ) and a detector, some type of photo-diode should do. The detector should be shielded from the ambient light, possibly mounted in a tube. Alignment would be another issue with this system, ie the transmitter and reciever would have to be aligned properly...

    Hope this helps....


  • Registered Users, Registered Users 2 Posts: 10,896 ✭✭✭✭phantom_lord


    Ok maybe I was wrong... Thesystem "consist of two units: an infrared light source (photo-transmitter) and an infrared light detector (photo-receiver)" that works out to 200 feet. http://farmtek-fti.com/wireless_eyes.htm. An dbasically I just want to have a dectector on the reciever eye so that a LED lights up when the two eyes are in line with each other.


  • Registered Users, Registered Users 2 Posts: 10,896 ✭✭✭✭phantom_lord


    Ok maybe I was wrong... Thesystem "consist of two units: an infrared light source (photo-transmitter) and an infrared light detector (photo-receiver)" that works out to 200 feet.Something like this http://farmtek-fti.com/wireless_eyes.htm. An dbasically I just want to have a dectector on the reciever eye so that a LED lights up when the two eyes are in line with each other.


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