Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donations

Links below open in new window

ArcticMyst Security by Avery

Searching for 495nm

farbe2

Well-known member
Joined
Oct 3, 2018
Messages
306
Points
63
Hello Guys.


Some long long time ago, 495nm diodes appeared out of nowhere and disappeared as fast as they appeared.

Its a long shot but i have a little hope left.

Is there someone out there that still has a diode laying around and wants to get rid of it?
 
Last edited:





Joined
Aug 31, 2016
Messages
769
Points
93
Some of the 488nm diodes get near that wavelength when over-driven.

Sharp GH04850B2G
1663619905511.png
 
Last edited:

CurtisOliver

0
LPF Site Supporter
Joined
Jun 12, 2015
Messages
7,636
Points
113
I have two GH04850B2G's (SB308B292) in my collection. One hitting 489nm and the other 493nm.
The 493 is being driven at 220mA.

So it is possible still with that diode to see the higher end of cyan.
 
Last edited:
Joined
Feb 4, 2010
Messages
3,287
Points
113
Didn't Phillip say he could get them binned from the factory at that wavelength? Or bin yourself, pricing may be around the same.

If not, the 488s are cheap and robust enough that you can drive with CV instead of CC, and overvolt a bit to dramatically shift the WL greener at the cost of more heat to deal with, which you may be able to handle with your new TEC capable driver. Dunno how devastating that is to diode health but at $25/ diode how much does that matter?
 

farbe2

Well-known member
Joined
Oct 3, 2018
Messages
306
Points
63
I brought one from phillip. I got the highest one he had. Out of ?50?40? only one was above 491nm.
491,1nm. Thats the one I've got.

Its still not green and i am very hesitant to drive them up to around 495nm with just increasing the current.
If i blow the one I've got, i dont think i can get a equivalent one.

Temperature shifting seems almost doable. I think these diodes drift with just 0,07nm/k or something like that. That would need mean running a 491nm diode at 80°C to get to 495,2nm.
Mhm 80°C seems a lot.

Do they have a knee or do they just die?

If a knee is present, driving them down the slope after the peak could work (at least for a short while).
 
Joined
Jun 25, 2017
Messages
352
Points
63
I have too a bunch of binned ones from the first batch ( look into my thread about binning them and also the selling thread).

I can get 497-502 directly from sharps factory (I posted their stock list in the discord channel some time ago).

Best
Singlemode
 
Joined
Aug 31, 2016
Messages
769
Points
93
I just built a couple laser pens using the Sharp GH04850B2G diodes driven @150mA and they were about 10nm apart from each other. I was surprised when I went to test one and it was much more of a sky blue color than cyan.


1718994061493.png
484.5nm.jpg
494.3nm.jpg
 
Joined
Aug 31, 2016
Messages
769
Points
93
I've tested a few more in the last hour and it seems I primarily have 494nm but a couple 484nm are in there as well.
 




Top