WTB: Small-ish LPM that can handle 5W

I've been searching around and found that most of the LPM's discussed are no longer made, so I thought I'd ask you all directly

I'm looking for a laser power meter that can handle some stronger lasers, upto around 3W. Also from 405nm to 1064nm.

I did consider a LaserBee as they are priced well, but they only handle up to 1W - which isn't enough. I'm not looking for something too massive or too expensive.

Could you please recommend a LPM to suit?

Thank you

You could buy a Laserbee, and an ND:4 filter

What is an ND:4 filter?

AdamR said:

I'm looking for a laser power meter that can handle some stronger lasers, upto around 3W.

Click to expand...

Have a look at Ken's thermal LPM, the Kenometer. It measures up to 2W out of the box and up to 10W with an external DMM.

I reviewed it, in case you're interested.

AdamR said:

What is an ND:4 filter?

Click to expand...

IIRC, it is a filter that reduces the power of a beam by a certain percentage, so you can measure the power with the filter in place, and work out the actual power. For a Laserbee up to 3W, you need a ND:4 filter, that 1/4s the beam intensity.

You can get them here:
Clicky

That Kenometer is cheaper than a LaserBee Deluxe by roughly $50...
What is this external DMM required for up to 10W measurements, and couldn't I just use an ND4 filter instead?

AdamR said:

...couldn't I just use an ND4 filter instead?

Click to expand...

Yes, I don't see why not. In any case, much easier than hooking the Kenometer to an external "Digital MultiMeter".

Btw, you shouldn't choose one over the other just based on the price difference because they each offer up different strengths. Please review both thoroughly first... .

The laserbee isn't really designed for high powered lasers. I don't think I'd want to bother using an ND filter, but that's just me. The kenometers use coherent thermopile sensors with a larger target area more suitable for high powered diodes and such.

That kenometer has got my eye

Just wondering, but why would it require an external digital multimeter to display upto 10W? I see the LCD display has 4 digits on it, surely they can go up to 9999mW?

The Kenometer is a good LPM...
The Kenometer's Digital Display is a 2Volt DPM... and therefore can only
read to 1.999Volts or 1.999mW...
You would need a DPM that could measure to 9.999Volts to be able to
measure to 9.999mW in 1mW increments...
or you can use a Digital Multi Meter (DMM)..

BTW... the LaserBee I has a Peak Detector and comes with PC Interface Data
Logging Software on CD so that you can Data Log your measurements and even
save or print out a Graph of your Data Logging session on your computer.

The Standard LaserBee I comes ready to use right out of the box and is less
expensive than the Deluxe LaserBee I... and both come with the same features..

And as has been mentioned before.... Using a Neutral Density (ND) filter you can
measure higher powers than 1Watt with the LaserBee I...
Here is a link to some inexpensive Glass ND Filters (ND2+ND4+ND8)...

http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=120310772159


Jerry

I just want to chime in here not to contradict anyone but just to update this thread with information about the Kenometer. Bob_boyce had helped me create a selector switch and associated electronics so that there are 2 selectable ranges. 1mw-2W, and 2W-10W so that an external DMM is NOT required to read up to 10W.

That being said, please do NOT think that I'm trying to say that my meter is superior to laserbees. His meter is good and has some features that mine do not. I've personally tried his meter and it IS a good meter. It's a little bit more of a pain to have to use an external ND filter but in my opinion does NOT detract from the functionality or quality of his meter. You can ask Traveller, he asked me which was better and I honestly told him that there was really no "better" one and here were the differences.

Hey Ken... that is good news...

The new selector switch puts the Kenometer into a new ballpark...

I'm modifying a Kenometer as we speak to be able to read from 1mW to
10 Watts in 1mW increments..
If it all works out.. I wanted to do a Modification Review on how to do it
for the members that have a Kenometer...

BTW... if I though the Kenometer was not up to par... I wouldn't have bought
3 of them...

And if you need to measure over 1 Watt... at the present time your best bet
is the Kenometer... IMHO


Jerry