Low Power LPM?

I recently purchased an LPM and ARGLaser was kind enough to calibrate it for me. He estimates it can measure as high as 2.5W. But it has been suggested its not very usable below 10mW. Is this common for many LPMs?

I'm going to view a Helium Cadmium laser, this weekend, and I was wishing I had the LPM to measure its output. I expect it will be between 2 to 12 mW. But the LPM Arg calibrated wouldn't have helped me... maybe.

Should I be looking for another LPM to accurately measure in this low range? I have some 0.5 to 3mW HeNes I was looking forward to finally knowing their output. But I may have to keep waiting.

Will LaserBee's products, for example, give me accurate readings in the 0-5mW range as well as the 2000mW (445nm) range? Or am I expecting too much from a single hobbiest LPM?

Even the most sensitive 20c ophir's have a 200mW minimum measurement.. 0.2-20W afaik on their data sheet but they measure below 200mW just fine, I dont know about diy lpms u should give it a try though.. Zero it, and then measure against your calibrated diy lpm.

This is good to know, and explains why some people own several LPMs.

pschlosser said:

Will LaserBee's products, for example, give me accurate readings in the 0-5mW range as well as the 2000mW (445nm) range? Or am I expecting too much from a single hobbiest LPM?

Click to expand...

On the 1W version, measurements are actually truncated to 0mW if they're below 5mW.

Not sure about other variants.

Trevor

pschlosser said:

I recently purchased an LPM and ARGLaser was kind enough to calibrate it for me. He estimates it can measure as high as 2.5W. But it has been suggested its not very usable below 10mW. Is this common for many LPMs?

I'm going to view a Helium Cadmium laser, this weekend, and I was wishing I had the LPM to measure its output. I expect it will be between 2 to 12 mW. But the LPM Arg calibrated wouldn't have helped me... maybe.

Should I be looking for another LPM to accurately measure in this low range? I have some 0.5 to 3mW HeNes I was looking forward to finally knowing their output. But I may have to keep waiting.

Will LaserBee's products, for example, give me accurate readings in the 0-5mW range as well as the 2000mW (445nm) range? Or am I expecting too much from a single hobbiest LPM?

Click to expand...

For fairly accurate readings of power under 40mW you could
get a Sper Scientific Optical Sensor LPM for ~$200. It can
read up to 40mW.

Or you can get one of our HLPM II Laser Power Meter modules
on our Website or eBay. It can read from 1mW to 200mW and
also uses an Optical Sensor. It can read down to 405nm.

HLPM II

Our LaserBee A also measures from 1mW to 2Watts in 1mW
increments and can read down to ~300nm.

http://laserpointerforums.com/f64/new-15-discount-pricing-laserbee-laser-power-meter-70540.html#post1017250


Jerry

You can contact us at any time on our Website: J.BAUER Electronics

Does your HLPM have calibration constants for the main HeCd lines?

Also it's possible that HeCd lasers can be multiline in which case optical based meters become worthless.

MarioMaster said:

Does your HLPM have calibration constants for the main HeCd lines?

Also it's possible that HeCd lasers can be multiline in which case optical based meters become worthless.

Click to expand...

I agree... an Optical Sensor would be useless with a multiline
Laser. It would depend on the output characteristics of his
particular Laser (ie. wavelength/number of lines).


Jerry

You can contact us at any time through our Website: J.BAUER Electronics

lasersbee said:

I agree... an Optical Sensor would be useless with a multiline
Laser. It would depend on the output characteristics of his
particular Laser (ie. wavelength/number of lines).

Click to expand...

When we go optical, instead of thermal, don't we need to correct for wavelength? I'm unsure what correction data or charts the HPLM comes with. Jerry, can you clarify?

Just knowing a HeCd puts out 2mW versus 20mW makes a big difference, to me, regardless of the number of lines. Besides, the line efficiency of multiline Argons and HeCds are pretty well known. A total output test is good enough for a tire kicker like me.