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FrozenGate by Avery

Post your mA and mW






I suppose a pen style host is nice for brief shots, but these diodes dissipate so much power that something much larger is called for as a host to allow continous operation.

I don't mind pen-style builds, but i feel they have become inadequate in the last couple of years. Even for green pointers with half-watt pump diodes a pen host is difficult to stabilize, let alone these ~1 watt new blue diodes.

One advantage is that these diode lasers don't depend on temperature that much, and get more visible when they heat up, resulting in longer wavelength. The downside of that is that we will just have to figure out what temperature is still acceptable for decent diode life at certain currents.
 
The mode shifted to more of a uniform top-hat mode, I imagine this would make it a bit tricky to collimate at 2W- the now cold diode was tested when i returned home, still 528mw at 665ma so it is verified it didn't hurt it any.

My guess is the XJ-A130 has 1W rated diodes, while the nicer ones have 1.5 to 2W rated diodes. These ratings would be consistent with a new technology product launch, put over capacity diodes in to ensure low failures during the trial period of the new technology.

FWIW, The internal die is as big as a 1W 808nm diode, and gallium nitride is a more efficient lasing material than gallium aluminum arsenide phosphide.
 
i just finished my 445. im using a flex drive set to 810ma. i do not have an lpm yet. i am using 1-18650. this i can see the beam in my warehouse right now better than i can see my 100mw green (tested).
this 445 is a burning monster. Tonite i will be putting up build pix. woot woot

michael
 
chipdouglas said:
i just finished my 445. im using a flex drive set to 810ma. i do not have an lpm yet. i am using 1-18650. this i can see the beam in my warehouse right now better than i can see my 100mw green (tested).
this 445 is a burning monster. Tonite i will be putting up build pix. woot woot

michael
Click to expand...

What type of lighting conditions is your warehouse? I ask because I've heard over and over again that 1W of 445nm is comparable to 75mW of 532nm. How powerful do you think a 532nm would have to be in order to be the same brightness as your 445nm?
 
laser_freak said:
What type of lighting conditions is your warehouse? I ask because I've heard over and over again that 1W of 445nm is comparable to 75mW of 532nm. How powerful do you think a 532nm would have to be in order to be the same brightness as your 445nm?
Click to expand...

The relative brightness depends on whether you are talking about scotopic or photopic vision.

In the dark, ~900mW of 445 is about as bright as 300mW of 532.
In daylight, ~900mW of 445 is about as bright as 100mW of 532.

According to my eyes, at least.

Also, take into consideration Rayleigh scattering.

Edit: Also, one of the first things I noticed about this wavelength is that I am slightly near-sighted to it, but not as much as with 405nm. Far away, the light becomes blurry. Coupled with the large angle fast-axis divergence, this laser is not a distance pointer. It is very bright up close, however.
 
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i would lean towards what rapierce said. out side my green can lase an object further away than my 445. and my warehouse looks like an average living room in the the day time with blinds partially closed.

michael
 
Okay, I'm getting 85 mW at 263 mA after 405-G-1 (faulty driver.) It's actually quite nice at this power. I might have to have two of these; one "beast" and a general pointer.
 
proud2deviate said:
Okay, I'm getting 85 mW at 263 mA after 405-G-1 (faulty driver.) It's actually quite nice at this power. I might have to have two of these; one "beast" and a general pointer.
Click to expand...

How do you know the driver is faulty?
The threshold current of these diodes is around 200mA, so 85mW at 263mA seems ok.
 
It seems to me it takes a little while for it to level out to that 1:1 ratio after the threshhold is met.
 
I just metered mine again, and now I'm getting 105 mW. Has anyone heard of a diode increasing in efficiency once it has burned for a while, or can we chalk this up to the driver acting up? (I really don't want to disassemble just to test the driver. Thermal compound EVERYWHERE.)
 
Here are my results.

445nm Diode #1 Plot:

400mA -- 4.1V -- 237mW
500mA -- 4.2V -- 347mW
600mA -- 4.3V -- 460mW
700mA -- 4.4V -- 562mW
800mA -- 4.4V -- 656mW
900mA -- 4.5V -- 738mW
1.0A -- 4.5V -- 796mW
1.1A -- 4.5V -- 845mW
1.2A -- 4.6V -- 969mW
 
Exerd said:
Here are my results.

445nm Diode #1 Plot:

400mA -- 4.1V -- 237mW
500mA -- 4.2V -- 347mW
600mA -- 4.3V -- 460mW
700mA -- 4.4V -- 562mW
800mA -- 4.4V -- 656mW
900mA -- 4.5V -- 738mW
1.0A -- 4.5V -- 796mW
1.1A -- 4.5V -- 845mW
1.2A -- 4.6V -- 969mW
Click to expand...

What is your set-up? Does the diode have a pretty good heat-dump?
I noticed that these diodes can be temperature sensitive. ElektroFreak reported this, too.
During my testing, I've found that temperature can make a huge difference in output power. For example, when cool, the laser can hit 980mW easily. When warm, the laser will peak around 960mW and settle at ~920mW. After a ~3-4 minute on-cycle, the laser may output 880-900mW.

So if each current setting is tested one-after another, it may be helpful to allow a sufficient cool-down period between tests so that the numbers are not skewed by temperature variation (not necessarily saying that they are, of course).
 
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