Fish Tank Optics.
Why does the far side of a fish tank appear closer than it is when it's full of water?
The reason is that the light-waves while in the tank radiate in a circular manner when they leave the tank they are now radiating in a non-circular manner. The planes of those waves will hit your eyes at a vastly different ways. One eye will see the fish straight on while the other eye will see it sideways. As a result it's possible that in a way the fish will actually appear to be outside the tank.
Perhaps that would explain the somewhat queezy feeling you can get while looking into a fish-tank. One eye will see the plane of one light wave while the other eye will see the plane of another. It's not that the light bends is it? It's more like the wave front is at an odd angle. Where the light at first radiated spherically it is now radiating as an ellipsoid or Jelly bean shape. Here I'm showing a cross section so that it appears as ellipses. I think using wave fronts you get an intuitive understanding of how light works. What's causing me a bit of confusion is these ellipsoid wave-fronts. Are they moving more slowly in the direction of the wave front once they leave the fish tank? The momentum and actual speed of the light might be at a different angle from the wave front.
Note that in the drawing the fish appears not at the center of the ellipse at a location determined to be perpendicular to the wave fronts that have reached the eyes. I've made a lot of assumptions here however they seem in step with the general rules of refraction. It's just interesting that the wave fronts at the surface are moving at the same speed. Since this is impossible is that in itself the cause of reflection? I think not since the principle of the thing is always there at all points on the surface. The reflection would then be caused by something else. Maybe I'm wrong about the ellipsoid wave front.
Ok this is interesting because a laser doesn't bend at a point outside the fishtank does it? My main question was how come things look so bunched up inside a fish tank? It appeared from my previous article that glass makes things appear further away not closer. The apparent distance to an object through an aquarium would actually be further away because the light waves are squashed. You would think though if they are squashed they would have a different frequency but they don't Maybe slightly different. Maybe the fact that their wavelengths are so tiny that the change is less noticeable. Well I guess if the image of the fish were projected outside the tank you would be reaching for it and plus you would actually see stuff outside the tank so that it would block your view of things that actually are outside the tank. I mean perhaps if the index of refraction were high enough that might occur.
I'm thinking that the reflection at the top of the water is caused by the wavefront twisting around and perhaps heading back toward the water again. When you are under water and you look up at the surface there is an almost silvery quality to the water. It's not just normal reflection. The surface is almost mirror like. Almost all the light is bouncing back down because the light at the surface has turned the wave front back down on itself. The wave front outside the tank is moving faster than the wavefront under the surface causing the light to actually bend back down on itself. This is done so quickly that to actually see this bending of light you would need a microscope. But if you were to observe total internal reflection under a microscope is that the laser actually exits the aquarium and then comes back into it. (testable) Actually it may be even smaller than microscopic.
What's interesting is that a lens will work in vastly different ways if the image is inside the lens itself. This is because the original wave front inside the lens is perfectly spherical and the exiting wave front is distorted. I think it would be productive to perform experiments with images inside differently shaped lenses.
The reason is that the light-waves while in the tank radiate in a circular manner when they leave the tank they are now radiating in a non-circular manner. The planes of those waves will hit your eyes at a vastly different ways. One eye will see the fish straight on while the other eye will see it sideways. As a result it's possible that in a way the fish will actually appear to be outside the tank.
Note that in the drawing the fish appears not at the center of the ellipse at a location determined to be perpendicular to the wave fronts that have reached the eyes. I've made a lot of assumptions here however they seem in step with the general rules of refraction. It's just interesting that the wave fronts at the surface are moving at the same speed. Since this is impossible is that in itself the cause of reflection? I think not since the principle of the thing is always there at all points on the surface. The reflection would then be caused by something else. Maybe I'm wrong about the ellipsoid wave front.
Ok this is interesting because a laser doesn't bend at a point outside the fishtank does it? My main question was how come things look so bunched up inside a fish tank? It appeared from my previous article that glass makes things appear further away not closer. The apparent distance to an object through an aquarium would actually be further away because the light waves are squashed. You would think though if they are squashed they would have a different frequency but they don't Maybe slightly different. Maybe the fact that their wavelengths are so tiny that the change is less noticeable. Well I guess if the image of the fish were projected outside the tank you would be reaching for it and plus you would actually see stuff outside the tank so that it would block your view of things that actually are outside the tank. I mean perhaps if the index of refraction were high enough that might occur.
I'm thinking that the reflection at the top of the water is caused by the wavefront twisting around and perhaps heading back toward the water again. When you are under water and you look up at the surface there is an almost silvery quality to the water. It's not just normal reflection. The surface is almost mirror like. Almost all the light is bouncing back down because the light at the surface has turned the wave front back down on itself. The wave front outside the tank is moving faster than the wavefront under the surface causing the light to actually bend back down on itself. This is done so quickly that to actually see this bending of light you would need a microscope. But if you were to observe total internal reflection under a microscope is that the laser actually exits the aquarium and then comes back into it. (testable) Actually it may be even smaller than microscopic.
What's interesting is that a lens will work in vastly different ways if the image is inside the lens itself. This is because the original wave front inside the lens is perfectly spherical and the exiting wave front is distorted. I think it would be productive to perform experiments with images inside differently shaped lenses.
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