Are Laserbee's as accurate at higher powers?

[NightExplorer96]

Hello guys,

I have a bit of a dilemma here(when do I not ). I recently have been using and testing my 532 lab agaisnt my Laserbee AX and it seems the readings don't match up with what the previous owner had on eBay. His readings showed a minimum of 2.6W's of output with a peak of 2.8W's and it hovering between the two. On my end, upon getting the laser got a peak of 2.7W's but ever since then only quickly get a peak of 2.6W's and then it hovers around 2.520W's barely above what it's rated output is which is strange for a CNI unit. I've measured it with my pointers and my LG unit outputs below 5mW's and my other two output around 8mW's which makes sense.

I know Jerry calibrates these LPM before shipping them off bought thought I would ask anyway. If this is any help. I accidentally started the PSU without the laser head plugged in on accident, would that have any affect on the output of the laser? I did with a full on/off 655 red I had back in the past but since this is analog and nothing was connected, not even the positive/negative cables to the PSU from my brick power supply I am curious.

Thanks :thanks:
-Alex

 

[diachi]

Alex, you could always send that 532nm unit to me, I can compare it on my LaserBee.

That said, I don't know what Jerry's calibration procedures involve. He'd probably be able to answer the question for you.

Any damage to the sensor? Verified your modulation input voltage is correct? Allowed the unit to stabilize for 30 minutes or so?

Could always be that the sellers LPM was out of calibration and not yours. That could go both ways though. Lots of variables at play. The only way to be 100% sure is to verify against a high quality, recently calibrated LPM under the exact same conditions.

 

[NightExplorer96]

Alex, you could always send that 532nm unit to me, I can compare it on my LaserBee.

That said, I don't know what Jerry's calibration procedures involve. He'd probably be able to answer the question for you.

Any damage to the sensor? Verified your modulation input voltage is correct? Allowed the unit to stabilize for 30 minutes or so?

Could always be that the sellers LPM was out of calibration and not yours. That could go both ways though. Lots of variables at play. The only way to be 100% sure is to verify against a high quality, recently calibrated LPM under the exact same conditions.

Hello diachi,

Thanks for answering! No damage to the sensor that I know of and after experiments no damage could be found. I haven't let the LPM stabilize for quite 30mins so I'll do another test and see what I get today. If my reading still seems off I may indeed need to send it to see what it's reading. It's just strange a CNI unit would output just above what it's rated at though. Normally these are like 200-300mW's overspec

Thank you

-Alex

 

[lasersbee]

Hello guys,

I have a bit of a dilemma here(when do I not :eek). I recently have been using and testing my 532 lab agaisnt my Laserbee AX and it seems the readings don't match up with what the previous owner had on eBay. His readings showed a minimum of 2.6W's of output with a peak of 2.8W's and it hovering between the two. On my end, upon getting the laser got a peak of 2.7W's but ever since then only quickly get a peak of 2.6W's and then it hovers around 2.520W's barely above what it's rated output is which is strange for a CNI unit. I've measured it with my pointers and my LG unit outputs below 5mW's and my other two output around 8mW's which makes sense.

I know Jerry calibrates these LPM before shipping them off bought thought I would ask anyway. If this is any help. I accidentally started the PSU without the laser head plugged in on accident, would that have any affect on the output of the laser? I did with a full on/off 655 red I had back in the past but since this is analog and nothing was connected, not even the positive/negative cables to the PSU from my brick power supply I am curious.

Thanks :thanks:
-Alex

Hey Alex...

You could have sent us an E-Mail directly. I'm not
on the Forum as much as before but I do monitor
our business and personal E_Mails every hour or so.

As to your question you need to remember that the
LaserBee AX that you have has a 100% response time
of about 30 seconds. That is good to take accurate
readings of CW non DPSS lasers.

It is well known that 532nm DPSS Lasers constantly
change their output power.

1) the peak reading will only happen once in a while
and would require a very fast response LPM to see it.

2) the LaserBee AX is not fast enough to accurately
read that quick peak and will give you an average reading
of that quickly varying DPSS power output.

3) the longer you leave a close to 3W laser on the
3.1W Max LaserBee AX Sensor the readings will start
to read lower due to the Sensor and Head reaching
temperature equlibrium.

Is your LaserBee AX reading correctly with non DPSS
Lasers??

If you believe that your LPM is not reading accurately
you can send it back at any time to have the calibration
checked.


Jerry

 

[NightExplorer96]

Hey Alex...

You could have sent us an E-Mail directly. I'm not
on the Forum as much as before but I do monitor
our business and personal E_Mails every hour or so.

As to your question you need to remember that the
LaserBee AX that you have has a 100% response time
of about 30 seconds. That is good to take accurate
readings of CW non DPSS lasers.

It is well known that 532nm DPSS Lasers constantly
change their output power.

1) the peak reading will only happen once in a while
and would require a very fast response LPM to see it.

2) the LaserBee AX is not fast enough to accurately
read that quick peak and will give you an average reading
of that quickly varying DPSS power output.

3) the longer you leave a close to 3W laser on the
3.1W Max LaserBee AX Sensor the readings will start
to read lower due to the Sensor and Head reaching
temperature equlibrium.

Is your LaserBee AX reading correctly with non DPSS
Lasers??

If you believe that your LPM is not reading accurately
you can send it back at any time to have the calibration
checked.


Jerry

Thank you Jerry

-Alex

 

[Encap]

The seller you bought it from says: "This is unused and in perfect condition. I bought this as a backup and never needed it. It's making 2.5W cold, and averages 2.7W after warming up with 5V on the analog input. "
See here: https://picclick.ca/CNI-2500mw-532nm-25W-Green-Analog-Laser-Module-262819495721.html

Maybe email CNI the model and serial number and ask them for a copy of the original test data details on file for that particular unit if it concerns you. They should have it on file if it was not purchsed a long time ago/depending on when it was made. Maybe you can find out the original output power stability --if it <10% then a 200mW variation is within that.
Less thn 10%/< 10% is commonly purchased by lighting and light show people which I think is what the sellers business is ---he is currently offering a RGB projector and a lighting controller panel see: http://www.ebay.com/sch/ajd462/m.html?item=262840990456&rt=nc&_trksid=p2047675.l2562

All DPSS lasers even same make and model are different at the outset thus the different general output stability spec groupings available and the use of < (less than) on many of the specs. rather than a definate number + they constantly change their output power as Jerry has mentioned. They also change over time with use due to several factors.

 

[lasersbee]

Thank you Jerry

-Alex

N/P Alex...:beer:

The seller says: "This is unused and in perfect condition. I bought this as a backup and never needed it. It's making 2.5W cold, and averages 2.7W after warming up with 5V on the analog input. "
See here: https://picclick.ca/CNI-2500mw-532nm-25W-Green-Analog-Laser-Module-262819495721.html

Maybe email CNI the model and serial number and ask them for a copy of their original test data on file for that particular unit if it concerns you. They should have it on file if it was not purchsed a long time ago/depending on when it was made.

Is that the Laser you bought and are testing Alex ?


Jerry

 

[NightExplorer96]

N/P Alex...:beer:



Is that the Laser you bought and are testing Alex ?


Jerry

Yes.

What is strange is that the laser starts off at 2.6W then slowly goes down to the mid 2500mW. While this meets specs its strange I'll let the LPM stabilize for 30mins before adjusting it to 0 and try again

-Alex

 

[Rivem]

Yes.

What is strange is that the laser starts off at 2.6W then slowly goes down to the mid 2500mW. While this meets specs its strange I'll let the LPM stabilize for 30mins before adjusting it to 0 and try again

-Alex

As Jerry said, the problem might be that

3) the longer you leave a close to 3W laser on the
3.1W Max LaserBee AX Sensor the readings will start
to read lower due to the Sensor and Head reaching
temperature equlibrium.

You should let the laser warm up off of the LPM first and then move it onto the sensor. If the seller was using a proper lab-grade LPM, he would not have had this problem, so he could accurately read the laser's output as it warmed up. The LaserBee LPM is a great hobbyist solution, but there's a reason lab-grade setups are so much more expensive.

 

[NightExplorer96]

As Jerry said, the problem might be that



You should let the laser warm up off of the LPM first and then move it onto the sensor. If the seller was using a proper lab-grade LPM, he would not have had this problem, so he could accurately read the laser's output as it warmed up. The LaserBee LPM is a great hobbyist solution, but there's a reason lab-grade setups are so much more expensive.

Good idea! Will do

-Alex

 

[NightExplorer96]

Okay.

I let the LPM sit in my room for about 10mins and made it zero'ed. I then ran my laser for about 10mins to warm up and stabilize. Upon aiming it at the LPM I got about high 2.5W's. I then slightly tilted the LPM upwards and got a huge jump to about 2620mW but then the sensor started smoking which means the laser must have been too focused?

I dunno

-Alex

 

[diachi]

Okay.

I let the LPM sit in my room for about 10mins and made it zero'ed. I then ran my laser for about 10mins to warm up and stabilize. Upon aiming it at the LPM I got about high 2.5W's. I then slightly tilted the LPM upwards and got a huge jump to about 2620mW but then the sensor started smoking which means the laser must have been too focused?

I dunno

-Alex

Sounds like you burnt the sensor, you need to be careful with these sorts of powers. Burning the sensor will affect the accuracy of your power readings if your beam is hitting one of the previously burnt spots.

Weird that it only happened when you tilted it though...

Jerry made a good point, response time on his LPMs is quite high (not bashing them!), so you may be missing the peak.

 

[NightExplorer96]

Sounds like you burnt the sensor, you need to be careful with these sorts of powers. Burning the sensor will affect the accuracy of your power readings if your beam is hitting one of the previously burnt spots.

Weird that it only happened when you tilted it though...

Jerry made a good point, response time on his LPMs is quite high (not bashing them!), so you may be missing the peak.

Yeah. Response time? I just can't understand why I barely am getting 2.6W's but upon first getting the laser got around 2.7W's and from then never got past 2.7W's. I did mention accidentally running the PSU without the head plugged in but only for a few seconds and nothing seemed broken from there. *sigh*

-Alex

 

[Seoul_lasers]

Just an aside... Probably beaten to death by now..

Personally tested the lasberbee (3.2W) against a calibrated Ophir 20C -1-Y-A
while the laserbee misses the initial peak (often upwards of 10% higher than the average power), the average power measurement is well within (1.0% - 0.5%) of the Ophir sensor. That's quite accurate.

My 12x Bluray laser from 2011 gives me ~730mW pk on the ophir, and
695mW av. The Laserbee shows ~690mW av.


Diachi looks to have beaten me to it...

The laser output should more or less cover the sensors surface (50-90%). (defocused) and centred.
If the beam is focused then you risk damaging/burning off the broadband absorbent coating.
This effectively creates a dead spot on the sensor.

:can:

 

[CurtisOliver]

I need to remember this next time I test lasers over 2W. Good tip. +rep :beer:

 

[NightExplorer96]

Hey guys,

I did another run and got an output between the high 2500mW to the low 2600mW so about 100mW's above spec. Do you think the previous owner simply had peaks when he recorded 2.8 & 2.7W's? So what it averages on output is what im getting?

-Alex