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[PIC HEAVY] Got a Monochromator!

Wolfman29

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Hey everyone. So a few days ago I decided to take a risk and bid on a Bosch and Lomb monochromator. Anyway, long story short, I won it for about $230 and it arrived today!

Without further ado, here are the pictures that I know you guys have been waiting for!

The Monochromator!



Now, that's the device... what about some pictures of it doing what it's built to do... measure monochromatic light? (Or isolate light, really.) Well, first I should explain how I managed to get consistent results. I've found that if the laser enters the device off axis, it will not get a correct reading. So, I basically just stuck the laser right on the slit so that it got the maximum light through it while maintaining perpendicular entry. So, for example, I just stuck it right up against the argon laser and the greeNe! Heh.

Anyway, I bet you're wanting verification that it works, so here are some pictures of it taking measurements :p

ARGON!
From left to right, top to bottom, we have 458nm, 477nm, 488nm, 497nm, and 514.5nm.
458nm:







GreeNe!

543.5nm:





DPSS:
From left to right, top to bottom, we have 589nm, 671nm, 532nm, and 473nm.







Diode Lasers!
From left to right, we have "405"nm and 520nm.


In conclusion, it looks like it typically reads about 2-3nm high. I think I am seeing about 2nm resolution, too. I have the slits set pretty low. I'm trying to think of a way that I can maybe use specular reflections instead of direct incidence. Anyway, if anyone has any ideas, that'd be awesome :D

Alright, so that's everything. Hope you guys enjoyed!


- Sam
 
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Re: Got a Monochromator!

Hope it's well calibrated!

Congrats on the new instrument :)
 

Wolfman29

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Re: Got a Monochromator!

So before I headed out to class, I did some rudimentary testing, and it looks like it's well calibrated (tested it on a 589nm DPSS and my argon on stand-by). It just reads 2nm high, it looks like. Gonna open it up this weekend, possibly.
 
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Careful with that direct power method.

You can burn out the PCM. One of those things that's not fully a yes or no, but it's possible. if it's sensitive enough, you can just shine the light on a piece of paper in front of the entrance slit.
 

Wolfman29

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The PCM? What's that stand for? Because I opened up the monochromator and it's literally just a grating and a few mirrors.
 

Cyparagon

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You opened it up and didn't take pictures inside? For shame :tsk:

I'm trying to think of a way that I can maybe use specular reflections instead of direct incidence. Anyway, if anyone has any ideas, that'd be awesome :D
You can use a fiber. Fasten the fiber to the entrance so that it reads properly, then you have an input (the other end of the fiber) that doesn't care about incidence angle. A $1 TOSLINK cable should work okay.
 

The Lightning Stalker

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Hey no fair, that is too easy! You should see how we have to take wavelengths here in the
back woods, all uncle Tom's cabin and whatnot. :spank:
 
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The PCM? What's that stand for? Because I opened up the monochromator and it's literally just a grating and a few mirrors.
The PCM is behind the exit slit, the photodiode that says there is light.

Also, we told you that! That's how monochromators are designed.
 

Wolfman29

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Oh. Bloom, there isn't a PCM on this one =p Just another slit. I was thinking about adding a PCM though. I don't think all monochromators are designed that way. At least not this one!
 

Blord

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I am surprise to see the device is analog. The number display looks very cool.
 

Wolfman29

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It's really old. I've seen ads from like the 60s with this model in it. Surprised it still works, but hey!
 




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