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ArcticMyst Security by Avery

the DT0811 is brighter then the 803T?

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Re: Unexpected high power

brtaman said:
Glasserfan, did you get a chance to do a comparison yet?

I am waiting until it gets dark to do the comparison:) I'll take the pics outside for best results.

A few more hours [smiley=thumbsup.gif]
 





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Re: Unexpected high power

I may be able to get a few minutes of time on a spectrometer, and I'm not far from Dave (relatively speaking). I'll see what I can do, and then we'll see what we can do.

[smiley=thumbsup.gif]
 
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Re: Unexpected high power

That would be excellent! Do you have access to a spectrometer at work?

I would love to see the wavelength difference between daguins 70mw 811 and the 150mw 803t, given that the 70 is more visible. How much do these spectrometers run for though, couple k?



Thanks
brtaman
 
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Re: Unexpected high power

I have a DT0811 here I could slap in a module really quick for some pictures. I dont really have any PHR lasers here though to compare with :(

But I can compare via memory :p
 
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Re: Unexpected high power

[smiley=thumbsup.gif]

All set, I can use the spectrometer in the same lab as the power meter I can use occasionally here (which isn't the lab of the professor I work for, but is the lab one of my officemates works in). That lab is pretty busy now, but next week or maybe the week after I should be able to get a quick measurement of the wavelengths of some diodes. I have an 803t at 100mA, but I don't have a DT0811. I can't go crazy and measure a whole bunch of lasers, but whatever someone wants me to look at, within reason, I can check out then.

Also, whatever I check out, it either needs to be a lower power or one that I can use all the way uncollimated. My officemate is a little hesitant to through a lot of power at the spectrometer, so either lower power or, more likely, one that I can just take the collimating/focus lens completely out of or screw out to a very wide area.


brtaman- A spectrometer, like anything else, it completely depends on how much of one you want. You can get a cheap one for a few thousand $ (maybe even a surplus used one for hundreds, I've never looked into it much), or you can get a good one and it'll be a lot more. Sensitivity, resolution, channels, whether its fiber-optic mounted, the quality of the software packaged with it, it all matters a lot. My last lab had a 4-channel near UV through short IR, with only .5nm resolution and the cheapest/least featured software possible. It was in the single-digit thousands.
 
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Re: Unexpected high power

I was just about to post about my new 803T being unusually brighter. It does look actually more blue. I can't compare, but it's from GooeyGus, so he can vouch for this.
 

daguin

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Re: Unexpected high power

360freak said:
I was just about to post about my new 803T being unusually brighter. It does look actually more blue. I can't compare, but it's from GooeyGus, so he can vouch for this.

I have only had one 803T that I thought was brighter.  Ace owns it now.


pullbangdead said:
I may be able to get a few minutes of time on a spectrometer, and I'm not far from Dave (relatively speaking).  I'll see what I can do, and then we'll see what we can do.

[smiley=thumbsup.gif]


Well I don't own this one anymore.  I have four other 0811's here.  As soon as I get some more drivers, I can make another one. I am very willing to ship it to you to have these measured.

Peace,
dave
 
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Re: Unexpected high power

pullbangdead said:
[smiley=thumbsup.gif]

All set, I can use the spectrometer in the same lab as the power meter I can use occasionally here (which isn't the lab of the professor I work for, but is the lab one of my officemates works in). That lab is pretty busy now, but next week or maybe the week after I should be able to get a quick measurement of the wavelengths of some diodes. I have an 803t at 100mA, but I don't have a DT0811. I can't go crazy and measure a whole bunch of lasers, but whatever someone wants me to look at, within reason, I can check out then.

Also, whatever I check out, it either needs to be a lower power or one that I can use all the way uncollimated. My officemate is a little hesitant to through a lot of power at the spectrometer, so either lower power or, more likely, one that I can just take the collimating/focus lens completely out of or screw out to a very wide area.


brtaman- A spectrometer, like anything else, it completely depends on how much of one you want. You can get a cheap one for a few thousand $ (maybe even a surplus used one for hundreds, I've never looked into it much), or you can get a good one and it'll be a lot more. Sensitivity, resolution, channels, whether its fiber-optic mounted, the quality of the software packaged with it, it all matters a lot. My last lab had a 4-channel near UV through short IR, with only .5nm resolution and the cheapest/least featured software possible. It was in the single-digit thousands.

I think this might be worth looking into. After all I have only seen people measuring power level and not the wavelength. ::)

--hydro15
 
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Re: Unexpected high power

daguin said:
I'm wondering now if it is the DT-0811 diode. I have one (that I was going to be putting up FS later today) that also displays this.

I built two lasers in the same host to figure out how they would go together (so I could help noob's with the build). In one of them I put a DT-0811 diode @ 100mA, just cause I had it here. It is putting out 70mW. In the other I put a PHR-803T diode @ 165mA. It is putting out 150mW. When I took them outside to see them in the sky, I thought I had them mixed up. The wrong one was brighter. I brought them back inside and double checked. I hadn't mixed them up!

The 70mW laser LOOKS brighter than the 150mW laser, even though it is putting out less than half the light! If they are shining alone, I do not "see" much of a difference. The DT-0811 looks a bit "bluer", but that is all. The difference is really only evident to me if there is another beam shining next to it. It is much like the 660nm vs. 635nm difference. The 635nm LOOKS a bit brighter if you shine it alone, but if you shine it next to a 660nm beam, the difference if clear.

The 150mW laser burns more and faster than the 70mW. The 70mW does burn stuff, just not as fast. I haven't done any "long-range" comparisons of them. I haven't done any beam characteristics comparisons. I have only shined them next to each other.

Maybe Ace will chime in here. He got to see the beams next to each other as well. Has anyone else built a laser using the DT-0811 diode? We need to get these to someone with a spectrometer. I thought I had this worked out, but I didn't. Anyone with a spectrometer out there wanna do a comparison? I have a few others here. I wanted to do destructive testing of them to determine the upper limit of their power, but I haven't got nearly enough response from my WTB thread to be able to do the testing I wanted to do. Maybe I can salvage the effort (and cost) with a wavelength test instead. Plus, with a wavelength test, the diodes are still viable and available to build lasers with after the tests :)

Hmmm. Maybe we need a new thread or just re-name this one? How about it Hydro? You willing to change the title of your thread to attract more discussion of the DT-0811 diode?

Peace,
dave

Your right in thinking its a slightly longer wavelength. It takes about the same amount of time my lab-ray does. The thing about these BR diodes is that when the wavelength goes up it gets brighter and the hotter the diode is the higher the wavelength is and i am pretty sure this diode is
about 409nm. Reds get slightly dimmer as the current goes up.

--hydro15
 
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I finally got the chance to get this posted:)

I lit up al three in a dark room, and outside, to compare. At least with the three I have, none of us here at my house can see a major difference in color between the three...

Attached is the pic of the three beams at night. The DT0811 @ 125mA is the top beam, the middle is the 160mA 803T, and the bottom is the 803T @ 150mA. All three builds have a clear acrylic lens.  The 150mA build has a weak battery in it, and is usually slightly brighter than it appears. Both 803T builds are brighter then the DT0811. The pic is fairly close to what we see in reality, but as with all digital cameras, not perfect.  :-/

The pic was shot outside on a Canon A650IS, set at 3MP resolution, 32 second exposure(gotta love CHDK), no color boost or anything. I did turn the exposure compensation up to +2.

My guess is that some of these are surely bluer, therefore appearing brighter, but as with the 803T, there is a lot of variance between individual diodes. I am very interested in the results from the spectrometer:)
 

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Maybe not.. I may just have a DT0811 that is on the low-end of the spectrum.  It would be nice to test as many of each as possible on the spectrometer to get better results:)

This seems to be the unfortunate thing about 405Nm diodes.. there is too much variance between them to build lasers from them with consistent results.
 

daguin

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Glaserfan said:
Maybe not.. I may just have a DT0811 that is on the low-end of the spectrum.  It would be nice to test as many of each as possible on the spectrometer to get better results:)

This seems to be the unfortunate thing about 405Nm diodes.. there is too much variance between them to build lasers from them with consistent results.


Yeah. That was a joke. It's late. I forgot to put in the emoticons. I am a professor. I would never make a decision based on such a small sample. At this point we have 66% of the observed diodes showing "brighter" beams. We also have at least two 803T diodes showing the same phenomenon.

Peace,
dave
 
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Very true:)

I knew you were joking of course, and have the same hopes as you about the DT0811 can be seen as something other than the inferior diode that nobody wants to end up with [smiley=thumbsup.gif].

My apologies for sounding a little too serious....
 
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Re: Unexpected high power

360freak said:
I was just about to post about my new 803T being unusually brighter. It does look actually more blue. I can't compare, but it's from GooeyGus, so he can vouch for this.

I set this laser to 100mW. I didn't get a chance to see it at night, but from what I observed in my bedroom with the light on, it seemed a lot brighter to me than it should have. I checked the power again, still right around 100mW. When I finished 360freak's laser I didn't have any other blu-rays to compare it to (I am a blu-ray diode serial killer.... I like to give them way to much current and see if they will live... yeah... I'm weird...) but it DID appear to be brighter than it SHOULD have been in a light room at 100mW.
 





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