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Measuring light intensity

  1. Sep 15, 2008 #1
    Hello everybody,

    I am trying to measure the light intensity of light going through a plexiglass (U Shaped) in a fish tank using led. I would love to see accurate voltage measurements due to the change in the liquid level. I tried photodetecr transistors; it wasn't accurate at all. I am thinking about using Light Dependent Detectors and Photo Diodes. Any suggestions ?


    Thanks !
     
  2. jcsd
  3. Sep 16, 2008 #2

    berkeman

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    Staff: Mentor

  4. Sep 16, 2008 #3

    dlgoff

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    I would probably want to use a lux meter. They use photo-diodes. For example these meters or maybe a light meter kit.
     
  5. Nov 2, 2008 #4
  6. Nov 3, 2008 #5

    dlgoff

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    See pin 7 (+supply) and pin 4 (-supply)? It's the LF351N JFET input op-amp.
     
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