| MadSci Network: Physics |
This could be a couple of things. A laser beam has speckle, since it is coherent light. The speckle could look like blinks as you move it around the wall and the texture varies. A simpler explanation could be wall texture. If the wall is bumpy, the spot will blink.
Barring that, perhaps the batteries aren't connected very well. :-) Ordinarily, the laser light shouldn't blink at all, provided it is aimed at a flat surface and everything is working properly. Try it on the blackboard and see if it looks like it blinks there.
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