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Sharp GH0631IA2G 185mW Single Mode 638nm (now with Power/Current Charts!)

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Anyone ever mess with this diode before??

Datasheet

These have popped up on eBay and I picked one up a while ago. I haven't done anything with mine yet, but I may fire it up soon if I get the time. They are cheap at least!

Sharp 638nm 180mW Orange Red Laser Diode LD Single Mode | eBay

I fear these will be another case of the "LPC-840" which turned out to be a dud. Hopefully these sellers are actually selling the diode they say they are.

Edit: Just ran a power test with my shitty variable PSU. It behaves like it is supposed to! I went to 310mA which is over driving it pretty hard, which is pretty unnecessary for a diode like this. You want to run them light to keep their wavelength lower. :)

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Re: Sharp GH0631IA2G 185mW Single Mode 638nm

I don't know, but I do know I've been disappointed by LaserLands too many times in the past not getting what they said I was getting.
 
Re: Sharp GH0631IA2G 185mW Single Mode 638nm

They aren't the only sellers of this diode, but I guess that probably doesn't mean much. I'll have to make a classic PIV chart for my diode...and will have to get it spectro'd before long.

Maybe it will run closer to 630nm if I under drive it...
 
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Re: Sharp GH0631IA2G 185mW Single Mode 638nm

For an item like this, it probably is what they say.

I got ripped off buying laser diode modules which put out half the power they said they would and then, not learning my lesson, buying a beam expander which had a lens 30% smaller than they showed in their photograph with a measurement grid next to it. They play the "send it back" game, costing so much to send it back to China it wasn't worth it. They can ship tings to us cheap due to having their mail subsidized by their government, but we pay a high price to send an item back. This works to their advantage on ebay.
 
Re: Sharp GH0631IA2G 185mW Single Mode 638nm

I may get one of these soon. I had an idea for a laser made completely out of Chinese components. It would be an interesting build because the components are cheaper but not the best quality.
 
Re: Sharp GH0631IA2G 185mW Single Mode 638nm

Alaskan said:
For an item like this, it probably is what they say.

I got ripped off buying laser diode modules which put out half the power they said they would and then, not learning my lesson, buying a beam expander which had a lens 30% smaller than they showed in their photograph with a measurement grid next to it. They play the "send it back" game, costing so much to send it back to China it wasn't worth it. They can ship tings to us cheap due to having their mail subsidized by their government, but we pay a high price to send an item back. This works to their advantage on ebay.
Click to expand...

Every time I run into this problem I open a case against the seller and tell them I'll send it back if they pay for postage. With over 350 eBay buys, it hasn't failed me yet. I'm surprised you weren't able to do this with the beam expander. I suppose it is too late by now. :cryyy:
 
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Re: Sharp GH0631IA2G 185mW Single Mode 638nm

I'm loving that low voltage. Looks like a single cell with a linear driver would be possible. Also it would be interesting to see what it would do if cooled. Based on the spec sheet it seems to like it cool.
 
Re: Sharp GH0631IA2G 185mW Single Mode 638nm

I'm curious looking at the data sheet why this diode would be any different from other 638nm diodes. My bet is its luck of the draw as far as what wavelength you get like 510-520nm diodes and how it's driven. When I put up the pics for the 510-520nm lasers I have it was mighty surprising to find that out of all of them one of the 520nm turned out to have the most blue tint:
http://laserpointerforums.com/f45/pete-s-favorite-color-green-98333.html

In the first beam shot take a look at the one second from right. Also look at the last beam shot second from left in the groupinG as that's the same one.

Yeah, gotta love the "ship it back to us" for more than the whatever costs to begin with garbage.
 
Just ran a rough test on it and posted the results above. It behaved like it was supposed to, and I stopped at 310mA because I didn't want to kill it. I don't know what the Oclaro 170mW SM diodes can handle, but I would think that this is (just barely) the strongest SM 638nm diode on the hobby market. I'll have to put it on a spectrometer and see what kind of wavelength I'm getting. I may also have to give it a liquid N2 bath. :D
 
Re: Sharp GH0631IA2G 185mW Single Mode 638nm

styropyro said:
They aren't the only sellers of this diode, but I guess that probably doesn't mean much. I'll have to make a classic PIV chart for my diode...and will have to get it spectro'd before long.

Maybe it will run closer to 630nm if I under drive it...
Click to expand...

Nice find Styropyro.

I might just buy myself one.

Although, if a lower wavelength (before cooling) is what you're looking for, wouldn't getting a lot of 635nm 5mW diodes and binning them be another way.
Because you can get a 100 635nm 5mW diodes for less than $2 each ($1.2 is the lowest I saw). I don't know how low of a wavelength you could get, but it might be an option too.
 
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Batch testing a ton of 5mW diodes would definitely be a good/cheaper way to find a low WL diode, but in this case I wanted something on the strong side while keeping close or possibly slightly bluer than the typical center WL.

Just threw one into a pen with a flexdrive at 180mA, getting 115mW out through acrylic lens. I've never had a 638nm pen before!

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And this is how you get too many lasers...
 

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For $22 this seems to be pretty good deal. It's got a lot going for it: good brightness/mw red color, single mode, 5.6mm canned etc.

If you run it at 200 mA or so it'd make a great red pointer. Not something that'll set the drapes on fire, but a very visible red with good beam specs if you use a decent lens on it.

Driving these things hard is probably not really worth it: if they survive they'll heat up and shift to longer wavelengths making them less visible even if raw output power increases a bit.

Given the low forward voltage these would be great running off a single lithium cell.
 
go for the 622nm diode build next!!!:D

or make a laser powered by stick of dynamite.;)
 
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Those pens always look nice. I'm pretty sure the Oclaro are very close to the Mits 180 Jordan has (not sure why he doesn't sell the Oclaro 170 anymore) and will take 400mA or so at over 300mW. I'll have to look up my red pen builds and see what mine are.
 
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