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Coherent LaserCheck LPM with 445nm.

lasersbee

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Ask Yob... what the current was at what output...
Then you will have a baseline...

I know you said the batteries may not be fully charged...
Lets say your Laser is supposed to put out 1200mW
and your LC reading is 939... that is 261mW less or
an error of ~22%...

Talk to Yob and charge your batteries and test your Laser
again.. I'm curious as to the results..
BTW... what is the manufacture date of your LaserCheck..

Steve above also states his LC is close to a Thermal LPM...


Jerry
 

Cyparagon

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ludwigfan

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The laser's output is supposed to be between 1 Watt and 1.2 Watts. I don't know why anyone would expect it to be exactly 1200mw. Just under 1 watt would be acceptable to me anyway.

Strange goings on I find are that the Juice brand batteries supplied with the laser are measuring 4.17 and 4.20 V but only supply 0.76 amps now (0.86 yesterday) whereas the Tenergy Lifepo4 batteries I received today supply 0.98A even though they are only measuring 3.7 and 3.8 volts each. The lasercheck did not show an increase in power but it is near it's limit of 1W anyway.

So it seems as if the Juice brand batteries are having trouble delivering the required current, whereas the Tenergy are able to deliver just under 1A.

I'm glad I have a Jayrob 18650 kit on order because it's host should be able to heatsink better (it is bigger) and the 18650 battery and FlexV5 driver should be able to supply current better.

The tradeoff of course is that Yobresal's is cheaper and smaller so it's nice and pocket sized, which I also like. I will likely keep both.

So to recap:
Juice brand batteries: 4.17 and 4.20 volts; current: 0.76A
Tenergy Lifepo4: 3.7 and 3.8 volts; current: 0.98A

Beam seems to burn more easily with the Tenergy batteries as well. Just measured 981mW with the Tenergy batteries. Not a significant difference, so I think the Lasercheck is not accurate at it's limit, but it is not off by 50-100% as it is for others. I suspect something is wrong with their Laserchecks.


Also in case you're wondering LiFePO4 stands for Lithium Iron Phosphate.
Li=Lithium
Fe=Iron
PO4=Phosphate.

I don't know the chemical composition of the Juice brand batteries. Possibly Li-Ion not LiFePO4.
 
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Cyparagon

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If it's a boost driver that makes perfect sense. The driver is drawing 3.2W from the juice batteries and 3.6W from the Tenergy which is only an 11% difference. Additionally, the driver might have higher losses with lower input voltage, so that would bring the diode powers even closer.

Battery current ≠ diode current with boost drivers.
 

Nanolaser

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I had a coherent lasercheck a few years ago but i had to sel it because of money problems,... :cryyy:
 
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My Coherent lasercheck reads low on the blue end and highest near 800nm. The error is about -20% at 405nm and +15% at 808nm. It seems to be dead nuts accurate for 632nm which I assume is the calibrating wavelength.
 
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lasersbee

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My Coherent lasercheck reads low on the blue end and highest near 800nm. The error is about -20% at 405nm and +15% at 808nm. It seems to be dead nuts accurate for 632nm which I assume is the calibrating wavelength.
That's what I would say is the calibration wavelength as well...

Jerry
 




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