Laser Power Stability (rms)

[DrSined]

Hi, simple question, What exactly mean value "Laser Power Stability (rms)" at DPSS laser module?

Please explain as detailed as possible.

Thank you.

 

[NightExplorer96]

Hi, simple question, What exactly mean value "Laser Power Stability (rms)" at DPSS laser module?

Please explain as detailed as possible.

Thank you.

Laser stability means how stable a laser is. For example, a laser with a stability of 10% will not drift more then 10mW's, while a laser with a stability of 1% will not drift more then 1mW :yh:

-Alex

 

[diachi]

Laser stability means how stable a laser is. For example, a laser with a stability of 10% will not drift more then 10mW's, while a laser with a stability of 1% will not drift more then 1mW :yh:

-Alex

A 100mW laser* with those stability numbers will drift no more than you say.

A 1W Laser with a stability of 10% will drift no more than 100mW. It's a percentage of total output.

 

[OVNI]

Lots of info out there. From good simple explanations to complex white papers. Also, note that it's specified in percentage, %, of the laser power output as pointed out. Here's one source.

 

[NightExplorer96]

A 100mW laser* with those stability numbers will drift no more than you say.

A 1W Laser with a stability of 10% will drift no more than 100mW. It's a percentage of total output.

Dangit!

-Alex

 

[diachi]

Dangit!

-Alex

Don't sweat it!

 

[NightExplorer96]

Don't sweat it!

I won't haha.

-Alex

 

[ultimatekaiser]

yes. basically if a laser says ">100mW 5% stability over 4 hours RMS" it means that its guarenteed to output at least 100mW average or better minimum with no more than a deviation of 5% total output power over 4 hours at a consistent ambient room temperature while running with adequate heat-sinking/cooling.

 

[Cyparagon]

Mr. kaiser is confusing rms with peak. "5% rms" is COMPLETELY different from "5% peak." A 100mW 5% (rms) stability laser will vary considerably both over 105mW and under 95mW. I'm not going to try to explain rms in one forum post, but the easiest plain-English approximation is "average noise." The google can tell you all about rms if you want to know more.

 

[ultimatekaiser]

Yes and no. You're absolutely right about the nose bit. But on power specifications, if it's listed >100mW, Then that is its minimum output. It should always do more than listed. If it does less at any time, then it is considered defective/mis-calibrated. I do digress and note most of my lab lasers note power and noise separately on their spec sheets. (And I own quite a few) so it's important to check both. I've often seen companies list both power and noise under the same % difference, but not always. For example my GCS-405 notes <2% +\- <0.2%rms total for noise and <4% change in power over 8 hours. Read the specs carefully.