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ArcticMyst Security by Avery

destructive interference?

mfo

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Hey Jerry, you will probably spend a lot of your time wondering why your relationships lack that certain something: it's just you.

I hope you work it out mate.

BTW: @Admins kick me, ban me or whatever, in what world would I care?

I smell a returning, banned member. Perhaps Arenared? :)
 





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Jerry is the guy who respectfully reminds n00bs to not post in old threads unless it is important or what you have to say relates directly to the thread. I got a friendly reminder when I first joined, I'm sure many others have too. Without someone to help keep the place clean, it could get pretty messy around here.

As for the original question, I'd like to also add that when you get a piece of dust on your lens and there's that weird target-shaped artifact? In my head I've always attributed that to constructive and destructive interference (although that's probably not right, since I've no background in light other than my degree in "I like solid state lighting a lot")

And about making your own interferometer? That sounds sweet! I'm sure loads of us are trying to rationalize our purchases. Well, I bought mine to do scientific experiments with!!! :whistle:
 

HIMNL9

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Uhm, ok, cause the thread was undead .....

The interference mode, is also used in old instruments for measure the wavelenght of a laser, you know ?

Make a cavity with 2 mirrors, where the space is a multiple of , as example, 600nm (must be a multiple just cause there's no way for mechanically build a cavity identical to the wavelenght ..... i want to see someone working on a 600nm lenght cavity, LOL :crackup:), and where one of the mirrors can be precisely moved, for adjust the distance from the mirrors from a multiple of 400nm and a multiple of 800nm (just as example, for remain in the "visible" field :p), and where the mirrors are semitransparents (not total mirrors, like the OC mirrors of the gas lasers).

Place a photodetector rear to one mirror, and then shine your laser through the other laser ..... then tune the distance from the mirrors until you get the maximum reading at the photodetector ..... this is your wavelenght ..... (ok, ok, simplified a lot, but this is the principle of working :p)

This happens cause, when the distance is a precise multiple of the wavelenght that you shine in, you generate a "constructive interference", as any laser cavity works, after all ..... ofcourse, if you get a lenght that is a multiple of the wavelenght plus half, you get a destructive interference for the same principle (but anyway you can never "destroy" totally the light, just decrease it a certain degree .....
 
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Hey Jerry, you will probably spend a lot of your time wondering why your relationships lack that certain something: it's just you.

I hope you work it out mate.

BTW: @Admins kick me, ban me or whatever, in what world would I care?

Gee.... You seem to be the one that spends a lot of time
wondering about his own relationship issues...

Nothing to work out here.... I have none..:na:

BTW... You seem to feel you have done something wrong that
requires banning....
:thinking:

Almost seems like I already know you.... :whistle:
With that attitude................ Enjoy your short stay....

As HIMNL9 said... it would have been better to open a new Thread... IMO


@ the active members... the Interference discussion does sound
interesting now that we have a few new members with more ideas
since this thread was originally opened...:cool:


Jerry
 
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monkey.jpg
 
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mfo

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Would a new thread about interferometers also be full of personal, off-topic and derailing comments from you like this one is now? I mean, who cares if the thread was started a long time ago? Why was it necessary to muddy this one up with your personal need to admonish the new poster? Are you the LPF nanny?

Are you the LPF nanny? You seem to get off on trolling Jerry.
 




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