The discussion centers on Young's double slit experiment, specifically comparing results from a shallow slit and a significantly thicker slit, approximately 35 times thicker. Participants noted that the thicker slit produced abnormal patterns, likely due to reflections between the two surfaces, which is why thinner slits are typically preferred. The conversation also explored the effects of camera apertures and the phenomenon of observing double slit patterns through eyelashes when looking at a light source. The importance of lens removal in the experiment was emphasized, as it significantly altered the observed patterns.
PREREQUISITESPhysics enthusiasts, educators, and students interested in optics, laser experiments, and the principles of light interference will benefit from this discussion.
Lok said:On the thick slit, the abnormality might be explained by reflections between the 2 surfaces. That is usually why slits are thin.
The into the laser photos, is there any slit, aperture anything? how about the cameras aperture it has it's own effects.
Btw. One simple and clear way to see double slit patterns is through your eyelashes. while looking to a small source of light ( light bulb at 5m) close your eyes a bit so you see through your eyelashes. The pattern will appear in rainbow colors as the light has most of the visible in it.
kevinfr0st said:thanks for your reply,the banding is no different just more of them,the photos into the laser was straight into laser (still had lens in laser) with dig cameras the processer (i think)likes to hex shapes that are round,with the pin hole shot i loaded at end of video it took 8 or 9 times to get the pin hole to look round and not hex,you can see the banding,i had also found out you don't need to shine laser through the slit,shine it on to a wall 5 feet or 10 or 20 and look through the slit at the dot,i also found out if you hold a double slit to your eye and hold up a lens the slit focas the immage,the strange thing is when the lens is removed the experiment don't work,you get banding inside the slit,like you see if you hold the slit to your eyes,
any more comments welcome
Lok said:When you say "remove the lens" you mean the lens that focuses the laser? And if so how does the laser look like? I mean does it diverge in a huge angle? Are you sure there are no other patterns "without the lens" as for an unfocused laser they will be extremely faint ( try photographing with a very long exposure time. Plus they might overlap if slit is too big.
The other effects of seeing patterns through slit close to the eye are known and documented.