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Optics of extended sources

  1. Oct 30, 2009 #1
    I'm currently trying to look into the optics of extended sources. Google doesn't seem too helpful.

    Anyway, I have just been thinking about it and thought that surely one of the easiest problems would be the intensity at a screen at a particular distance from an incoherent, spatial extended source.

    To me it looks pretty much like an electrostatics problem, common as an undergraduate.

    I'm envisioning a line of infinitesimal sources, which will each contribute some light to a point. Which assuming a Lambertian emitter will be the intensity of that infinitesimal point but taking into account the 1/r^2 drop off and the cosine of the angle of the point.

    I then integrate over the whole source. However when I put this into maxima (can't do it manually) I get some horrendously long expressions.

    Am I doing something wrong with my model and can anyone suggest an introductory text for extended sources?
  2. jcsd
  3. Oct 30, 2009 #2

    Andy Resnick

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    It is covered in many optics courses, but disguised. In fact, what you are asking is the far-field diffraction pattern for an aperture, when the field aperture is not a (coherent) plane wave but an incoherent field, and the aperture is shaped like your source. Try that approach and see what happens.
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