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Homework Help: Projector optics

  1. Sep 20, 2004 #1
    i am in need of help pretty quickly here.i will have to design a projector design using a fresnel lens and the projection lens.i need to find and derive the equations for the lenses and calculate the distances between the lenses and the lens and the screen.
    this is what i require to have :
    d1 - distance from the light source to the fresnel lens
    d2 - distance between the fresnel and the projection lens
    d3 - distance between the projection lens and the screen
    f1,f2 - focal lengths of the fresnel lens
    f3,f4 - focal lengths of the projection lens
    In my case i know the values of the focal lengths and the distance between the light source and the fresnel lens.

    i will have to find d2 and d3. also i need to find the net magnification factor for the light source which will be my object.
    any help will be greatly appreciated.
  2. jcsd
  3. Sep 21, 2004 #2
    can someone please help me with the porblem mentioned.
    thank you
  4. Sep 21, 2004 #3
    please help me as soon as possible.otherwise i am in very big trouble
  5. Sep 22, 2004 #4
    37 views and still no reply.but i guess i cant expect people to help me out with this.It's just that i am desperate.
    So may be some one could tell me what the image distance will be in the case of the fresnel lens - to the screen or to the projection lens
  6. Sep 24, 2004 #5
    please help guys and gals
  7. Sep 24, 2004 #6
    after visiting this thread the first time i thought my problem is going to get solved within a couple of days.But looks i am the unlucky person in this board whose posts are going completely unnoticed by the experts
  8. Oct 3, 2004 #7
    In case of the fresnel lens it is giving out parallel beam of light so should i have to take the object distance to be infinity for the second lens which is the objective lens as it is getting the parallel beam incident on it.or shld be the distance from the fresnel lens as the object distance.
  9. Oct 3, 2004 #8


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    Homework Helper

    It would appear that not too many people here have experience with Fresnel lenses. You might have to dig into a good optics text!
  10. Oct 3, 2004 #9
    Thanks but then again none of the optics texts have anything related to this.
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