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Thread: increasing range in infrared

  1. #11

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    Thanks for the suggestion, but is there any readily available IR sensor that detects modulated IR and outputs the signal strength as an analog voltage instead of an on/off digital value?

  2. #12

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    There are such sensor modules that return an analog value....like SHARP GP2D12...

    However these are costly n not readily available here...Try using tx rx pair for the analog values...or use tsop wid varying frequency to approxiamate the distance....

    there is an article on ir distance sensing that gives more info on this forum...

  3. #13

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    Those sharp sensors are triangulation based range sensors. What Im looking for is an analog signal strength output.

  4. #14
    Senior Member Android
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    Default hi

    Hi,
    I was wondering if we could use a charge pump to drive an IR LED. Boosting the voltage and limiting the current through the LED...
    Has anyone tried this before? similar to driving a white torch led...
    Cya
    Mohit Bhoite
    http://mobots.solarbotics.net

  5. #15
    Super Moderator T-1000 docel's Avatar
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    Default Re: hi

    Quote Originally Posted by orion
    Hi,
    charge pump to drive an IR LED. Boosting the voltage and limiting the current through the LED...
    Good idea, but can be done only for Illumination/ Indication (LFRs). The drive is a n AC drive@ some Freq. This will vary due to various reasons. The sensor will detect this as an AC source.
    But Modulation will be very cumbersome, difficult and almost impossible as the Modulating frequency will stop the Boost osc.

    Although technically feasible, it may be quite difficult for a hobby/ student user. The method I have suggested in an earlier post is the Proffessional method of High voltage Pulsing , large switching current PWM@ the Carrier freq. This is in the shape of a higher voltage (eg. 12V) reduced series resistance and high instantaneous current ( ~1A) with a minimal component count.
    Since the current is discontinuous, the LED will survive the higher current, as long the transmission is in short bursts with sufficient time for junction cooling.

    As this simple method achieves a larger range, it should be sufficient.
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

  6. #16
    Junior Member Newbie
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    Assalamo Allykum !

    You opearte the emitter lED by 555timer. As you will increase the frequency of the 555timer the ragne on the sensor will increase.

    I have apply this any I have achieved the range of 4 feets.

    Allah Hafiz

    Zeeshan Sharif
    Zeeshan Sharif
    Industrial Electronics Engineerign
    IIEE, PCSIR
    Karachi, Pakistan

  7. #17
    Senior Member Cyborg
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    Zeeshan,

    The frequency should match the TSOP receiver (if using that) for best performance.
    if its TSOP1738, the Freq should be 38KHz precise. little deviation in the Freq. will reduce the range at receiver.

    TSOP receivers are available for various frequencies, near the 38KHz,...ex. 40Khz.

    cheers!
    Vivek
    --
    " To get working ideas effectively, I try to fail as fast as I can. "
    Richard Feynman
    --
    http://www.youtube.com/watch?v=JqlawTD_9B0

  8. #18
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    i was thinking if it would be a good idea to use a aluminium foil made small disc arould the transmitter as well as the reciver to concentrate the rays to get a better reciving.... how about it ....worth a try.....

  9. #19
    Senior Member T-1000
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    Default

    use a aluminium foil made small disc arould the transmitter as well as the reciver to concentrate the rays to get a better reciving.... how about it ....worth a try.....
    the structure ll be big and ll not be easily mountable on a small robot.

    using multiple leds in d array gives better results..{25 to 30 cms}.....
    if u thought u r the only mad person on the planet.......u got serious competition here

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