|MadSci Network: Physics|
Sorry for the delay, I had trouble retrieving my email for the last week... OK, so someone previously tried to answer your question but apparently did not answer it to your specifications. I will try my best to answer your question as best I see it. It seems that what you are asking is why you are "seeing" this spiking effect from light sources such as street lamps. I would interpret this in a few ways. For one, the covering on a street lamp has inperfections in the bulb surface or outer transparent covering, meaning that it is not perfectly smooth. Because of this the rays emanating from the source refract and reflect in ways that divert the rays. When this happens you will see a spiked appearance to the light source or that interferance is occurring with the rays overlapping. This results in destructive and constructive interference which we see as bright and dark spots coming off a light source such as this. Things like the moisture in the air, windshields, and even the air cause these rays to deviate in the space between you and the light source. Some people also see spiked appearances to light sources if there eyes don't focus properly, such as in far-sighted and near-sighted people. I hope that I answered your question or at least gave you some things to investigate. If you have further questions are want elaboration on any of these items let us know. Thanks
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