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FrozenGate by Avery

Estimating power output of blue laser

Joined
Oct 15, 2007
Messages
510
Points
18
Hey guys,

I've owned a 445 laser for quite some time now, but have never been able to use a LPM to test its output power. However, how would I best estimate its power output knowing the following facts: The flexdrive's current is set to 1.5A, and it pulls around 2.2A from a freshly charged battery at 4.2V. An AW 18650 2900 mAh to be more precise. I am also using the 405-G-1 and the Aixiz 445 glass lens

Thanks!
 





Your probably looking at around 1.4W minimum. It all depends on the efficiency of the diode. Then with the G-1 lens your pushing that up to ~1.8W (assuming 32% increase).
 
Around 1.8W with the G-1 lens? For some reason I always thought it should be around the 1.5 W mark, give or take a 100mW. Too bad I can't test its power output. In that case, how much power would make a big enough difference to make it worth buying a new 445?
I have been considering >2W handhelds, but I am not sure it is worth it if I am getting around 1.8W out of the one I have right now. What power output would make a considerable difference in brightness and burning power?
 
There are no big differences between 1.6Watt and 2Watt. Without holding the lasers side by side you see almost no difference in brightness and burning power. The 2 Watt laser has the biggest bragging rights. :D
2 Watt 445nm lasers are still rare. I think there are not much avaiable.
 
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My 445 has almost the exact same specs as yours (I run a 2600mah AW,) and it'll put out over 1.7 watts at peak. After the first few seconds, things start to heat up, and output drops a bit (100-200mA, depending on how long I run it,)

As previously noted, diode efficiencies will vary, but I'd expect yours to be in the same ballpark.
 
I have a DTR 445nm diode at 1.62A. It puts out 1.5W with regular Aixiz glass.

1.5 / 1.62 = .9259

.9259 x 1.5 = 1.3889

So with the regular Aixiz glass and only my one data point, I would estimate your power at ~ 1.4W.

With a G2 lens my same diode puts out 1.95W

1.95 / 1.5 = 1.30

1.30 x 1.3889 = 1.8056

So with the G1 lens and only my one data point, I would estimate that your output would be ~ 1.8A, which is a 30% increase and essentially what bobhaha suggested above.

Is it an "A" or an "M" diode?

Glenn
 
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I have a DTR 445nm diode at 1.62A. It puts out 1.5W with regular Aixiz glass.

1.5 / 1.62 = .9259

.9259 x 1.5 = 1.3889

So with the regular Aixiz glass and only my one data point, I would estimate your power at ~ 1.4W.

With a G2 lens my same diode puts out 1.95W

1.95 / 1.5 = 1.30

1.30 x 1.3889 = 1.8056

So with the G1 lens and only my one data point, I would estimate that your output would be ~ 1.8A, which is a 30% increase and essentially what bobhaha suggested above.

Is it an "A" or an "M" diode?

Glenn

The diode is about a year old. Should be an M diode.

So is it safe to assume a 1.8W power output with the G-1 lens?

If I were to sell it in the future, how should I rate its power fairly?
 
To make things complicated I have a M140 recently bought and it does only 1300mW at 1.6A with a G2 lens. Another is already hitting 2Watt. Nothing can be sure without a LPM
 
To make things complicated I have a M140 recently bought and it does only 1300mW at 1.6A with a G2 lens. Another is already hitting 2Watt. Nothing can be sure without a LPM

You mean both these lasers are identical, yet you get 2W from one and 1.3W from the other?
Does the diode make that much of a difference? How would I advertise its power then? Or should I just leave it to the buyer to figure out?
 
The diode is about a year old. Should be an M diode.

So is it safe to assume a 1.8W power output with the G-1 lens?

If I were to sell it in the future, how should I rate its power fairly?

Sorry guys, but this thread is just nuts. First of all, a diode that's a year old is an A-series not an M-series diode. But more importantly, there's too much variability to be trying to give any kind of indication of output power merely based on current and lens type.

An A-series diode running at 1.5A with a G1 lens could be producing 1.8W, or it could be producing 1W. No exaggeration here. Both are equally likely. You absolutely cannot guess. I've seen A-series diodes set at 1.8A that barely do 1W, and I've seen A-series diodes set at 1.6A that break 2W.

You cannot rate the power at anything if you're not testing it. If you wanted to be safe, and not get it LPM'd, but still provide some indication of power, you would have to play it conservative and say 1W+.

When faced with this ^ reasoning, a lot of people will say "oh, ya, but this looks really really bright, there's no way it's just 1W". This is equally fundamentally flawed as an argument, because you have no way to know the wavelength of two diodes, and this too is variable. If you have laser A which is known to be 1.8W, and laser B appears as bright, but you don't know its actual power, you can't just estimate it to be similar. If laser A was 441nm and laser B was 453nm, then laser B could be much closer to 1W and yet still look around as bright as the 1.8W laser A.

Bottom line, you cannot estimate this stuff. Even with knowledge of input current, the reality is that there is just way too much variability to try and estimate or eyeball output power. Tons of people are faced with this issue all the time, and in the end, it's almost always a recipe for disaster. If you want to sell the laser, you need to get it LPM'd.
 
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Sorry guys, but this thread is just nuts. First of all, a diode that's a year old is an A-series not an M-series diode. But more importantly, there's too much variability to be trying to give any kind of indication of output power merely based on current and lens type.

An A-series diode running at 1.5A with a G1 lens could be producing 1.8W, or it could be producing 1W. No exaggeration here. Both are equally likely. You absolutely cannot guess. I've seen A-series diodes set at 1.8A that barely do 1W, and I've seen A-series diodes set at 1.6A that break 2W.

You cannot rate the power at anything if you're not testing it. If you wanted to be safe, and not get it LPM'd, but still provide some indication of power, you would have to play it conservative and say 1W+.

When faced with this ^ reasoning, a lot of people will say "oh, ya, but this looks really really bright, there's no way it's just 1W". This is equally fundamentally flawed as an argument, because you have no way to know the wavelength of two diodes, and this too is variable. If you have laser A which is known to be 1.8W, and laser B appears as bright, but you don't know its actual power, you can't just estimate it to be similar. If laser A was 441nm and laser B was 453nm, then laser B could be much closer to 1W and yet still look around as bright as the 1.8W laser A.

Bottom line, you cannot estimate this stuff. Even with knowledge of input current, the reality is that there is just way too much variability to try and estimate or eyeball output power. Tons of people are faced with this issue all the time, and in the end, it's almost always a recipe for disaster. If you want to sell the laser, you need to get it LPM'd.

I agree with what you said and had no idea the degree to which one diode varies to another could be so large! Had I known that, I would not have tried to estimate the output power of my laser.

I guess it would be safe to just call it 1W+ laser, but that would make pricing a little tricky because I would have to sell this laser having in mind that it only outputs 1W, and pricing it accordingly.

I guess investing in a LPM would not be such a bad idea after all. Especially if you see yourself in this hobby years from now.
 
Information removed was not related to A140 diode in OP.

Glenn
 
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