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

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

Pushing an Osram PL450B, Wavelength Shifting?

IsaacT

0
Joined
Aug 25, 2010
Messages
5,947
Points
83
Just curious as to how high I could get the wavelength of a PL450B single mode diode to go if I pushed it with the current. If I can get it up to around 460 that should be considerably lighter than a 445, correct?

Just trying to cheat the wavelength system :p

Thanks,
Isaac
 





sinner

0
Joined
Oct 27, 2011
Messages
2,565
Points
83
Afaik the wavelength would tend to decrease and go on the blue'er side with increasing current..

eg:

WL - mA - mW
447nm 500 450
443nm 1000 950
442nm 1500 1600
441nm 1900 2000
 
Joined
Feb 10, 2013
Messages
2,125
Points
63
According to the datasheet, the diodes go warmer in color as the case warms past 40 decrees celcius. That tells me that the harder you drive it, and the warmer the case gets, the closer to 460nm you will get.

WB, I just bought this diode too. I was going to drive it at 1.6A...and I got to see it that way for a bit before the driver shorted out and died. It was a nice blue that to my eye was a little brighter. I've had bad luck with that driver...Time for a new one.
 
Joined
Aug 3, 2011
Messages
284
Points
0
According to the datasheet, the diodes go warmer in color as the case warms past 40 decrees celcius. That tells me that the harder you drive it, and the warmer the case gets, the closer to 460nm you will get.

WB, I just bought this diode too. I was going to drive it at 1.6A...and I got to see it that way for a bit before the driver shorted out and died. It was a nice blue that to my eye was a little brighter. I've had bad luck with that driver...Time for a new one.


The Osram PL450B cannot be pushed to 1.6A, the highest you should go with it is around 300mA. Any higher your likely top fry it.
 
Joined
Feb 10, 2013
Messages
2,125
Points
63
Excuse me...I was looking at the datasheet for the more powerful PL TB450. These diode names are too similar!

I would think though that the PL450B would have similar characteristics in regards to it's wavelength shift.
 
Joined
Aug 3, 2011
Messages
284
Points
0
Excuse me...I was looking at the datasheet for the more powerful PL TB450. These diode names are too similar!

I would think though that the PL450B would have similar characteristics in regards to it's wavelength shift.


I thought that might be what you were thinking of, I'm actually going to be building a PL TB450 soon myself, what driver were you having trouble with?
 
Joined
Feb 10, 2013
Messages
2,125
Points
63
I was using a 1.6A adjustable X-Boost. These are great drivers. I think I may have shorted a resistor or something when sticking it to the heatsink. I used plenty of epoxy, and it's not supposed to be electrically conductive. All I know is that on the bench, it lased beautifully. Once I got it into the host, I got nothing but a very hot batter. After removing the driver and putting it on my test load, I get absolutely nothing. IDK if I killed the switch or what.

I think I may be leaning against single 3.7V battery builds. I've had so many issues keeping these boost drives cool and gone through all sorts or ways to heatsink them. I may switch to bigger builds with buck drivers to avoid the heat issues.

I just pray I didn't kill the diode. I won't find out until I get another driver shipped out.
 

IsaacT

0
Joined
Aug 25, 2010
Messages
5,947
Points
83
In my mind, the more powerful a build, the longer the host I like to use. And not just because I like big lasers, but because I HATE short runtimes. When I use my lasers I am constantly turning them on and whatnot so single cell build don't get me there in that regard.
 
Joined
Feb 10, 2013
Messages
2,125
Points
63
I hear ya. I've been picking hosts that were on the cheaper end of the scale..meaning single cell. I think I am done with that period. Now, with the Krytons coming soon, and my SAiK on it's way from China, it's time to try something different. I really think I am a short distance from making my own labbies and just selling hand-helds to pay for it.
 
Joined
Aug 3, 2011
Messages
284
Points
0
Ya, I'm giving one of the new benboosts a try. 1.6A also :). Single 14650 Ehgemus Host. Ill let you know how it works out once I can get the diode.


edit: Oh and on the OT, I remember at some point reading the blues shifted up from heat, which is another reason its hard to notice the decrease in power due to heat in blues.
 
Last edited:
Joined
Apr 26, 2010
Messages
4,175
Points
83
What's the hardest these diodes have been pushed? I have 2 947 Bens and a host+HS waiting for a 455-460nm build.

Also, with the X-Boost, I was talking to Angelos and I also made the mistake of using more than one cell with the drive. It's meant for single cell builds, 8.4V kills it.
 
Last edited:
Joined
Sep 12, 2007
Messages
9,399
Points
113
All LEDs and laser diodes will red-shift with either more current or higher die temp; inversely, they will blue-shift with less current or lower die temp. You won't get much more than a few nm by cooking your laser though, and it's also inherently hard on them to do so.
 
Joined
Jun 25, 2011
Messages
1,481
Points
63
my pl450 in the aurora is driven at ~380mW with a microboost. it gives about 250mW with a 3 element. it is kinda high for this diode - i killed another at the same current. you will be safe with 300mA i believe.
 




Top