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Spectral transmittance measurement

  1. Nov 30, 2012 #1
    Dear all,
    I am new in this forum; from a first sight I realized that you can help me to clarify a doubt.
    My experiment requires the measurement of spectral trasmittance of a simple by using a white light source (400-800 nm) and a silicon photodiode. I know that a proper measurement require to record first white and black illumination condition (100% and 0% transmittance) and to refer the measurement of the sample to this two measurement.
    My doubt is how to do the measurement by taking into account the spectrum of the light source and the responsivity of the photodiode.
    Thank you in advance

  2. jcsd
  3. Nov 30, 2012 #2


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    Science Advisor

    You can correct for the spectrum of the source if you know what it is. For incandescent, you can use black body spectrum. Other sources can be more or less complicated.

    The photodiode should first be calibrated across the spectrum. Is there a filter somewhere in the setup?
  4. Nov 30, 2012 #3
    Thank you K^2,
    I am using a monochromator to select specific wavelengths and I know the spectrum of the source. My doubt is how to calibrate across the spectrumby taking into account the responivity of the photodiode practically.
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