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Why did you think I would plough on through the rest of it?
Quote from: Bored chemist on 09/12/2022 17:45:54Quote from: hamdani yusuf on 09/12/2022 04:20:32Single edge diffraction of a narrow parallel light beam What made the beam narrow?Collimating lens.
Quote from: hamdani yusuf on 09/12/2022 04:20:32Single edge diffraction of a narrow parallel light beam What made the beam narrow?
Single edge diffraction of a narrow parallel light beam
Quote from: Bored chemist on 09/12/2022 17:48:10Why did you think I would plough on through the rest of it?To avoid embarrassment.
So the answer to "What made the beam narrow?" is always " a set of edges".
You think you have an experiment where there's only one diffracting edge.Are you sure?
Whose?Who will be embarrassed by you posting a video in which you say something that's wrong.
Quote from: Bored chemist on 10/12/2022 01:08:12So the answer to "What made the beam narrow?" is always " a set of edges".Here's a diagram of semiconductor laser. The width of the gap between the substrates determines the minimum width of the light beam at the focal point of Collimating lens. Without the lens, the light beam would be divergent, thus won't stay narrow for long.
You missed a few relevant bits.
Quote from: Bored chemist on 10/12/2022 12:26:59You missed a few relevant bits.After hitting the edges, the laser beam will diverge, until it's made parallel by Collimating lens.
Quote from: hamdani yusuf on 11/12/2022 06:10:25Quote from: Bored chemist on 10/12/2022 12:26:59You missed a few relevant bits.After hitting the edges, the laser beam will diverge, until it's made parallel by Collimating lens. No [ Invalid Attachment ]
Quote from: Bored chemist on 11/12/2022 10:06:41Quote from: hamdani yusuf on 11/12/2022 06:10:25Quote from: Bored chemist on 10/12/2022 12:26:59You missed a few relevant bits.After hitting the edges, the laser beam will diverge, until it's made parallel by Collimating lens. No [ Invalid Attachment ] Where do you think the top and bottom light beam coming out from the lens come from? What do you think the light beam would look like if the lens is removed?
Please try to pay attention.The edge of the lens will cause diffraction.So the light coming out of the lens can not possibly all be collimated.
The lens is much larger than the gap between the substrates.
It seems like you have been misled by a rough sketch.
which is showing how a semiconductor laser work.
It is finite.It diffracts.
When photographers talk about lens diffraction, they are referring to the fact that a photograph grows progressively less sharp at small aperture values – f/16, f/22, and so on. As you stop down your lens to such small apertures, the finest detail in your photographs will begin to blur.
A lens utilizes an aperture to help control depth of field, one of the most important tools in photography. However, leaving the aperture wide open will often result in slightly soft images, due to the lens's lack of ability to focus the light rays at that aperture. On the other hand, if you stop down too much, diffraction will also soften images because the extremely small aperture opening will bend the light in a different way, resulting in rays that aren’t accurately captured.https://www.bhphotovideo.com/explora/photography/tips-and-solutions/lens-diffraction-what-it-and-how-avoid-it
The diffraction is produced by the edges of the aperture, rather than the lens.
Quote from: hamdani yusuf on 13/12/2022 06:45:48The diffraction is produced by the edges of the aperture, rather than the lens.That is exactly what I said.Why are you repeating it as if it's somehow news to us all?Why waste that bandwidth?
What you seem not to realise is that a beam is only "finite" because it has been sent through some aperture.In the case of a laser pointer, the aperture is inside the laser itself.But there is always some sort of limit.So the answer to "What made the beam narrow?" is always " a set of edges".
The edge of the lens will cause diffraction.
Quote from: Bored chemist on 13/12/2022 08:33:51Quote from: hamdani yusuf on 13/12/2022 06:45:48The diffraction is produced by the edges of the aperture, rather than the lens.That is exactly what I said.Why are you repeating it as if it's somehow news to us all?Why waste that bandwidth?Quote from: Bored chemist on 10/12/2022 01:08:12What you seem not to realise is that a beam is only "finite" because it has been sent through some aperture.In the case of a laser pointer, the aperture is inside the laser itself.But there is always some sort of limit.So the answer to "What made the beam narrow?" is always " a set of edges".Quote from: Bored chemist on 11/12/2022 13:41:11The edge of the lens will cause diffraction.
Quote from: hamdani yusuf on 13/12/2022 09:27:43Quote from: Bored chemist on 13/12/2022 08:33:51Quote from: hamdani yusuf on 13/12/2022 06:45:48The diffraction is produced by the edges of the aperture, rather than the lens.That is exactly what I said.Why are you repeating it as if it's somehow news to us all?Why waste that bandwidth?Quote from: Bored chemist on 10/12/2022 01:08:12What you seem not to realise is that a beam is only "finite" because it has been sent through some aperture.In the case of a laser pointer, the aperture is inside the laser itself.But there is always some sort of limit.So the answer to "What made the beam narrow?" is always " a set of edges".Quote from: Bored chemist on 11/12/2022 13:41:11The edge of the lens will cause diffraction.You seem to have forgotten to make any sort of point.
You seem to have forgotten what you've said previously.
Young's interference experiment with single photons (Hamamatsu Photonics, 1982)This experiment, conducted by Hamamatsu Photonics in 1981, captured the dual nature of the photon by a special camera for the first time ever in the world.