Hi:
After a long time researching, I bought a 80mW analog modulated 473nm CNI laser from LaserGlow.com. I willingly paid a high price of 2400USD because they said that the laser would be legal with the CDRH and legal to import. My impression was that most folks import lasers into the US illegally, and I was unwilling to do so. For this I understood the price would be high.
But I had hoped at least the quality would be high as well.
The laser, LaserGlow model LRS-473-AM-80-5 was stamped and the test report indicated that the lab measured a whopping 139mW before shipping it to me. But when I received it, it measured about 75-78mW on three different LaserCheck wand power meters. I gave it a long 1hour warm up period, and still the same power. Then I looked closely at the beam, and close to the laser (near-field) the beam is a bit elliptical, with a crescent shaped blob below containing a small proportion of the power (probably a very small proportion, ie. 1-5%).
In the far-field, the beam looks fairly round, with less but slightly visible evidence of the crescent.
I sent the laser back to LaserGlow, and also sent my LaserCheck power meter. Paul Svec there said that he did find one of his power meters reading too high, but with another of their power meters, and with mine, he "including your and still achieve power readings of 100mW."
Well, I have the laser back, and I still measure the exact same readings of 75-78mW (88mW peak, when warming up but stabilizes to the 75-78mW range).
Actually, tonight I'm testing it for the second time since getting it back, and am seeing 86mW sustained for a while. Very peculiar. I don't have any long term plotting capability. Maybe I should invest in something...
So basically I have a laser that is a few mW under spec. sometimes, and just a few mW over other times. Beam profile is a bit less perfect than I had hoped for. Before I sent it back, I suspected their measurements were correct, and it got knocked during transit. But now I'm inclining to think it has always been this way, and the first time they measured it with a faulty power meter.
I am also concerned that it doesn't have the 5% stability that I ordered, though they measured 2.3%. That is a +-5% spec, so it might actually be Ok. I'm tempted to buy a PicoScope to check this, but am low on cash after buying the laser.
The only other thing is that I measure no where near 100mW like Paul quoted in the last email.
I will follow up tomorrow, as my computer will shut off automatically in 3 minutes...