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FrozenGate by Avery

Make Your Own Spectrometer for Under $1

Hey Sean, I used this method yesterday with great success.
The distance I used was 21 meters, which is a pretty large distance (not as large as what you used, though.)
I found that my schizophrenic 589's main wavelength really is 589, and proved it was right by checking a 532. Then I got some oddball results with my BTB HL (457nm) and my eBay Thor laser (513nm.) It also found my 7475 build to be just what I expected (525nm.)
Since I already have a DragonLasers grating, I just used n=3 on a 50 line/nm grating, but it worked fine.

:D
 
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HydroSean said:
The laser should be perpendicular to the grating and the grating should be parallel to the wall. For more precision you should do it at least 15ft away. Also use as many decimals as possible in the calcukation (6 should be good) until the end result, then round off. Hope this helps :D
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I did exactly 15 feet to the grating and all my numbers were out to the 6th decimal and still I am getting solid numbers, there was no need to round off, no matter if I used 3 or 6 decimals.

Like I said, I did the test from start to finish (3) separate times, repositioning the laser and grating each time and got the same results. So maybe those numbers are right if not as close as I'll be able to test them.

I do know though that the line closest to the center is alot bluer than all the others as the yellow tinge becomes obvious on the 2nd-8th.
 
Cali, where did you get that 532? Perhaps I should buy several to determine how likely they are to be multiline.
 
Sta said:
Cali, where did you get that 532? Perhaps I should buy several to determine how likely they are to be multiline.
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It's an e bay 301 cheapo, I went through around 40 of them (all purchased through (2) sellers who really are the same) and kept the ones that either acted weird or looked special compared to others, and when I found out about others having multilines I tested a bunch that I had and I ended up with an 8 line, 6 line and a 4 line, I also have (3) of them that do 2-3 lines but they go away within a couple seconds of turning on. I had the 8 line on for over 10 minutes continuously and all 8 lines stayed, it isn't untill it gets uncomfortable to hold cause the heat that it starts to fluctuate but always stays above 4 lines..

I need to find a camera that can realistically capture the differences, my cell phone camera shows all the lines as the same hue but rather shows the difference of intensity between them.
 
I just found 3 brand new 301s in my closet and these too are multiline, maybe this is alot more common than previously thought? Or do I just have some weird luck..

Another 5 line and 3 line
l04hev3l.jpg


Another 8 line?
MWXnvJQl.jpg


I do however have name brand 532s that only have one line but the 301s that I have been getting that are without the star cap, seem to be around 50/50 chance of me receiving a multiline.
 
Cali, could you possibly sell me one of the 8-line 301s? If so please PM me your offer. :)
 
CaliKirk said:
I just found 3 brand new 301s in my closet and these too are multiline, maybe this is alot more common than previously thought? Or do I just have some weird luck..

Another 5 line and 3 line

Another 8 line?

I do however have name brand 532s that only have one line but the 301s that I have been getting that are without the star cap, seem to be around 50/50 chance of me receiving a multiline.
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I've seen that before and I'm not sure if it's very common. Also those dots look really close in colour to one another. Should ask diachi, I think he has some experience with actually building them

Even looks like member Cyparagon had this before. Reading from http://laserpointerforums.com/f40/589nm-misbehaving-wrong-wavelength-97952-3.html , post 16

Cyparagon said:
I've had two different occurrences of cheap DPSS green pointers being multi-line for example.
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ElectricPlasma said:
Also those dots look really close in colour to one another. Should ask diachi, I think he has some experience with actually building them
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Read previous post about how my camera is picking them up the same, to the eye, every single line is different, and there was (1) line that had alot more blue in the one I tested yesterday- which I believe is why I was coming up with 527nm, pretty big gap from 532 which was my next line.

Edit: here's a short video, showing how one of the lasers can switch from 3 to 5 lines then can go back to 8, with each line changing intensity as each change occurs. Although while testing this laser yesterday I had it on for over 10 min continuously and it didn't change, if it operates in 3 or 5 lines, just leave laser off for a second and click- back to 8 as see on short video.

The other one, while not as bright as the first one, has been stuck on 8 lines, ran if for 4 minutes straight just now trying to take better pics but no luck.. :(

https://youtu.be/MKbgXuPJFSc
 
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CaliKirk said:
So I managed to follow the instructions and ended up doing it 3 times for consistency. Maybe I'm doing this wrong or I have the angle of laser to grating off a tad and I am thinking of another way for me to set something up that's more exact with perpendicular angles. Unfortunately I ran out of time and was only able to test the 8 line that I have, but here are the lines I'm coming up with...

1) 527nm
2) 532nm
3) 534nm
4) 536nm
5) 539nm
6) 542nm
7) 544nm
8) 547nm

I was only able to come up with even numbers and I noticed others didn't. So I must be doing something wrong!!
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Thanks, it's always good to have more data.

For the sake of not derailing this thread any more, I would suggest that we post our information of discussion about multi-line greens in this thread: http://laserpointerforums.com/f45/m...dpss-lasers-discussion-98658.html#post1442523.

I suspect that your measurements are 4-5nm low. One thing is for certain, baring any other transitions, the lowest wavelength transition that is responsible for our greens is the R2-Y1, which is no lower than 1060nm, at 10 Kelvin. So 530nm is likely the absolute lowest wavelength possible (with the 4F3/2 to 4I11/2 transition).
 
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I would very much like to get my hands on one of these "multi-line" 523nm DPSSLs. I have a good spectrometer would would like to do some testing. Don't want to buy half a dozen in hopes of getting one, though.
 
Here's the one I had with 3 lines:

RGVpointer-green.png


A device with better resolution is gonna be 5 figures.
 
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Cali you should try taking a measurement with a laser you have that's of a known wavelength and see if you can get that exact reading, if its different then you know your setup is incorrect, if not then you're doing it correctly.
 
HydroSean said:
Cali you should try taking a measurement with a laser you have that's of a known wavelength and see if you can get that exact reading, if its different then you know your setup is incorrect, if not then you're doing it correctly.
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Yeah I need to do something, I just need to set up an area where I can make sure everything is truly at 90°. And I should be able to also get an extra couple feet on the distance between the wall and grating from my last test. I do have other 532s that only have one main WL and I have multiple of them in order to verify.

Im going to get some supplies later tonight to be able to have everything locked down and permanent while testing.
 
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