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Looking for cheapest functional LPM (laser power meter). Will this one work?

GSS

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Thank you.. always wanted one and just could never get one. I have some units measured by others that would be nice to compare to..
Oh yes I will sure post about:)
 

foodson

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Mar 18, 2019
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Thank you.. always wanted one and just could never get one. I have some units measured by others that would be nice to compare to..
Oh yes I will sure post about:)
then start conversation in top menu with me and pass me your address and full name so I can send it signed for , to you, and we will take from there..
 

foodson

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Mar 18, 2019
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This 7000mw DIY LPM has been sent to member GSS.
Also I have done the test on 7W laser diode from Laser Engraver/Cutter and if you look at the video it measured 6.85W no probs what so ever..

LMP is out and on it's way to GSS..
Please don't message anymore as I have sent it out and no longer have it.. Thanks to all of you ..
For mr Jerry - >Please don't contact me nor replay to posts not merely relate yourself to it.. you said enough to me I did not like any of it.. it was very rude .. . .
 
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Lifetime17

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Dec 15, 2014
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Hi, One question why were you moving the beam up and down on the LPM. That should be about 8 to 10 inches from the LPM and directed in the center for a good reading. When the beam is hitting the sides of the LPM surface your readings will fluctuate.
Just curious , do you have a hand tremor I don't know. Glad to see that you shipped it to a great member very nice the gesture.

Rich:)
 

lasersbee

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Sep 20, 2008
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This 7000mw DIY LPM has been sent to member GSS.
Also I have done the test on 7W laser diode from Laser Engraver/Cutter and if you look at the video it measured 6.85W no probs what so ever..

LMP is out and on it's way to GSS..
Please don't message anymore as I have sent it out and no longer have it.. Thanks to all of you ..
For mr Jerry - >Please don't contact me nor replay to posts not merely relate yourself to it.. you said enough to me I did not like any of it.. it was very rude .. . .
Since you insist on calling me out by name... I will respond.

1) You show a Laser that you claim is 7Watts.
Where is the Laser being power tested on a know recently
calibrated good LPM to show it is really 7W ??

2) You shake that Laser all over the sensor surface without
showing the diameter of the beam. Is that so the Laser's
beam does not burn the coating if left on the same area of
the Sensor's active area ??

3) In your last video I can see that the Active surface of your
sensor is not pristine and seems to have been blemished or
scorched near the center (@6:05)

3) Your sensor head does not have enough mass to be cooled
by the heatsink sufficiently with the claimed "7 watt" laser
beam on it.
Watching your other video we see that you do not have an
accurate LPM to calibrate your LPM.

You merely used the Laser Diode spec sheet A/W numbers
to calibrate your LPM with 48mA of current running to the
Diode. And that we can not tell if it is the current directly to
the LD or the current the Diode Driver is drawing.

In the Video you show a current of 48mA and adjusted your
LPM to read 48... (@6:05) And when you dropped the current
to 43mA the LPM reading was only 40... (@7:09).
Quite an error of non linearity... 3mW on a 5mW change...

[EDIT]
Looking at the datasheet for the SLD3232VF that you used
for the calibration of that meter it seems that the slope
efficiency can not be relied upon for calibration because
the datasheet states that the slope can be from 0.9W/A to
1.8W/A. There is no way that your LPM is accurate to your
claimed 5%-6% error in Post #11 using this method.


@rich.. You are absolutely correct. Any knowledgeable person
that uses Laser Power Meters know that you don't shove a high
powered lasers right up to a Thermopile Sensor.


Jerry
 
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