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Thread: increasing range in infrared

  1. #1
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    Default increasing range in infrared

    i m using a simple tx rx pair{led's} for ir based obstacle detection...

    the prob is tat the range i m getting is very small{around 10cms}...
    i want something about a metre or so....
    how can i increase d range?/

    increasing current beyond wat i ve done is blowing up d tx led..
    i m driving tx led with a 6v supply and 40ohm resistor in series..
    if u thought u r the only mad person on the planet.......u got serious competition here

  2. #2
    Junior Member Newbie
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    Default Increasing range

    With Ir leds its tought.. even modulated Ir gives only that much. Why not try witha visible light LED and use a color selective photodiode.i've read they exixt!!


    --Madan
    http://invobot.tk

  3. #3
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    yes they do exist....

    not easily available though...
    cost is another factor...

    and tat wont be tat reliable too....

    so i want a soln to this prob using ir only..
    if u thought u r the only mad person on the planet.......u got serious competition here

  4. #4
    Administrator T-1000 vikas's Avatar
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    Default

    With Ir leds its tought.. even modulated Ir gives only that much. Why not try witha visible light LED and use a color selective photodiode.i've read they exixt!!
    Dont give wrong advice

    Use IR TX and TSOP RX's

    Read the following articles

    http://roboticsindia.com/modules.php...rder=0&thold=0
    http://roboticsindia.com/modules.php...rder=0&thold=0
    Vikas Patial

  5. #5
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    Default

    i tried tsop1738 some time back....38khz modulated ir...
    using it also i got a maximum range of around 12-14cms...
    has anyone got more than tat????
    if u thought u r the only mad person on the planet.......u got serious competition here

  6. #6

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    yeah .. i got aroud 10-12 feet easily with my TSOP 1738

  7. #7
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    yeah .. i got aroud 10-12 feet easily with my TSOP 1738
    tats huge....

    so how did u drive ur tx led???
    i m just having it in d collector arm of bs547 transistor and driving it from a 5v supply....
    and a 50percent duty cycle sq. wave is given at d base of d transistor..

    but this gave me hardly 12-14 cms...
    if u thought u r the only mad person on the planet.......u got serious competition here

  8. #8
    Super Moderator T-1000 docel's Avatar
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    hI ADDY!
    Range can be increased by increasing No. of LEDs or by increasing the Pulse current to the IRLED.

    Try a 4.7 ohm to 10 ohm resistance. HEATSINK the LED (?) !!!

    This can be done by having more metal area on the PCB and keeping the LED leads long (original). You can roll the leads around a 1mm dia. copper wire.
    My LEDs will trigger the TSOP , bounced off the roof or back-wall, about 40Ft!!!. Have made several @ >60 ft with a narrow 20 deg. beam-width IR LED @12v/10ohms/ darlington driver/36HKhz modulated..
    And---Keep the transmission short!!!
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

  9. #9

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    Is there any sensor that uses modulated IR like a TSOP but gives an analog output proportional to signal strength? TSOPs are good for transmitting data etc, but all the methods for using them for getting range estimates dont seem to work very well.

  10. #10
    Super Moderator T-1000 docel's Avatar
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    sUPARIO,
    You can connect a sensor as input to a LM3914. You can get a set of 10 levels of sensitivity.
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

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