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Wavelength-Shift, a non-scientific way :)

DJNY

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It is the same laser model Cyparagon tested here
His was 511nm, so I expect mine to be anywhere around this value at room temperature.

I cooled it in the freezer for about 2 minutes and used a hairdryer to heat it up during the vid.


The most interesting part is from minute 0:15 - 0:40
small size vid, better turn off the sound


In case you can´t or don´t want to watch the vid, these pictures were taken during the vid in video-mode:
Picture taken at the beginning / cooled down
Picture taken at the end / heaten up
 
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Re: Demonstrating wavelength-shift // non-scientific way :)

Kewl, thanks for sharing this with us DJNY. The second picture you took @1:38 looks almost like 532nm to me ;)

-Alex
 
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Cool...didn't expect THAT much of a noticeable difference! One thing you could also do is set the laser up on a tripod, and set a diffraction grating up in front of it- then put the camera in a fixed position and record the change on the wall. The dot should move as the wavelength increases, as well as the obvious color difference.
 
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Awesome! Gonna try that with mine today. How do you feel about the host? I personally like the feel of it, iirc cyp did not feel the same way.
 

DJNY

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Cool...didn't expect THAT much of a noticeable difference! One thing you could also do is set the laser up on a tripod, and set a diffraction grating up in front of it- then put the camera in a fixed position and record the change on the wall. The dot should move as the wavelength increases, as well as the obvious color difference.

It´s a bit more of a difference than I recongnize with my naked eye. Others might see more / less color changing.
It´s fun with the diffracting grating! Tried in the past. Maybe I will add such a vid with same setup later on.

Awesome! Gonna try that with mine today. How do you feel about the host? I personally like the feel of it, iirc cyp did not feel the same way.

I like the host a lot! IMO great laser, wavelength and host :)
 
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Man, I had no idea these diodes shifted so much-- holy crap. Maybe we should bug cy and see if he can spectro his in a similar test
 
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Yea I definitely need to get one of these sometime in the near future... :beer:
 
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Aye, that's a very noticeable shift. You can really notice it if you hover the mouse over the transport bar on the video and move it left to right. It goes from cyan to green.
 

DJNY

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Fantastic! Now I want to buy one of those :p

I´m sure it´s also visible with your 520nm and 638nm!
Except of the beginning, the wavelength shift it´s more like an fluent passage.
So better taking a vid and as trencheel303 suggested moving back and forth for better noticing the shift.
 
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Thing is.. I like those too much to risk them :p
I could try with the 635nm pen, though. Actually, I'm gonna do that right now.

Edit: works, or at least seems to work, looks more orange when cooled. Pretty nice, will try to setup with a grating to make sure it's shifting and maybe get a video.
 
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Had forgotten to post back here, better now than never.

I tried to record it with a grating - if there's a shift it's tiny. What I perceived earlier might have been placebo. My camera also sees no color variation - but it sucks and I doubt it'd pick it up even if it had worked.
 
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Might just be green diodes.

Got nothing to do today... gonna try it on the 462nm I have. Will report back--
 
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I wouldn't do it at that power level, condensation might kill the diode.
The dot of my pen was significantly "blurred" from the condensation (but returned to normal about half an hour later).

Let us know if you try it!
 
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I had already started the test before that. I noticed some blurring on the spot, however not much. Not much moisture should be where the electronics are as I've never taken the lens off of the module, and the only time the driver was exposed is when I hooked it up, I'm pretty sure in terms of moisture it should be fine.

As for the test... ooh boy does that make a huge difference.

I've also been running this for nearly 10 minutes now... host is just starting to reach room temp. Diode's driven at 2.4A, that's quite some time :D

--edit--

And it's as hot as I'll allow it to be now.

picture results (color difference shown in beams and below!)

attachment.php

attachment.php


Despite my camera not showing colors with 100% precision, this should sum it up. Basically, cooling made this an ordinary 445. I can't possibly say it any other way, it had the slightest hint of purple and everything. (though less than a regular 445 from memory) Maybe hit 455-460nm... I'm thinking this is ~465nm at room temp, and it probably hit ~468nm when it got heated up.

It didn't quite reach the same color as 473nm, I was able to tell the difference somewhat easily. Though it was closer than it normally got when I overheated it

Wonder if we can get ARG cyparagon or RHD to get quantitative tests...

______

Maybe it's the materials the diode is made out of, I'm fairly sure that this diode is made of the same stuff as the 520's
 

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