Light Transmission Through Half-Hollow Sphere

In summary, this person is asking for help with an optical experiment involving a spherical object and laser pointer. They are concerned with the weight of the apparatus and the safety implications of increased power density.f
  • #1
Homework Statement: hw
Relevant Equations: hw

I am looking for a light source, preferably a laser, for a specific optical experiment. The experiment involves a spherical object positioned 6 meters away from this light source. My goal is to shine the laser through the sphere, specifically aiming for the light to enter the larger hole and exit the smaller hole on the opposite side. The sphere itself is 2 meters in diameter (given its 1-meter radius) and it has two distinct holes on opposite sides: one hole has a diameter of 1 meter, while the other hole is significantly smaller with a diameter of 5 centimeters. I intend to conduct this experiment in a foggy environment or during the night, as this will enhance the visibility of the light beam. My ultimate objective is to ensure that the light exiting the 5-centimeter hole travels in a straight line, thus creating a beam effect in the surrounding environment.

Any suggestions on the appropriate lighting setup for this light transmission will be highly appreciated.

[Mentor Note -- Thread moved from the homework forums to the Optics forum for now]
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  • #2
Welcome to PF. :smile:

This seems pretty simple of the face of it. Aiming a tripod-mounted laser pointer to go through a 5cm hole that is 7m away is pretty trivial. Do you envision some problems with being able to do this?

(Please be sure to take appropriate laser eye protection precautions in these experiments, BTW).
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  • #3
I was assuming OP wanted the incoming beam to fill the 1m hole and the outgoing beam to fill the 5cm hole. Depending on power requirements there may be safety implications in increasing the power density 400×.

Perhaps the OP could provide a sketch of the idea? You should be able to cut-and-paste images into the editor, or use the Attach files button just below it.
  • #4
He might mean something other than what he said, but we probably should go by what he said.

I'm more concerned that the sphere weighs some tens of tons.
  • #5
After some thing...OP, what are you trying to do? If you scale your apparatus by a factor x, what happens to your signal? If instead of meter-scaled devices you had 10 cm scale devices, everything would weigh 0.1% of what your proposal does, and would fit on a table and not in a barn.
  • #6
Is there a purpose to this exercise? Most experiments have a specific hypothesis (or at least a hypothetical framework) within which one works. There is something to be said for just doing stuff, but it is not science just because you write it down.

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