- Joined
- Sep 12, 2007
- Messages
- 9,399
- Points
- 113
I bought it new from dragon lasers *here* for $420 + $25 shipping. I don't know how long it took to arrive, because it came while I was away on business. Somewhere between 1-3 weeks.
Payment was a pain in the ass. Both of my credit cards (in good standing) were declined by their payment service, and I ended up having to email them requesting a paypal invoice.
Size comparison with the CR2 model
Website beam specs claim 2mm and <1.5mRad. I measured the beam as ~2mm at aperture, and ~8mm at 11m which makes 0.55mRad. Not bad at all. Beam focus is not adjustable, by the way (at least not without modification).
My camera can't properly pick up the laser dot, so I didn't try. Beam profile is typically not Gaussian. Mode shifting happens often... every second or two while warming. Beam profile is always round, however.
IR output is negligible, and barely shows up on NIR camera. Estimated <0.1mW. Pump wavelength showed up on spectrometer as 807-808nm as expected.
Driver is linear. Site claims operation of 3.7V, but it regulates very well at 2010mA (+/- 5mA) anywhere between 2.6 and 4.5V. Note: 4.5V increases power dissipation over 3.7V and is probably not a good idea for long durations. Driver operates most efficiently at 2.6-2.7V. Unfortunately, that means if you wait until the laser goes out to recharge your cell, an unprotected lithium cell will be damaged from under-voltage.
Website specs instruct use no longer than 1 minute at a time, which is complete nonsense. Total power dissipation is roughly 7-8W, and a large chunk of aluminium can handle that without a problem. I left the pointer on for 30 minutes, and temperature rise topped out at 27C above ambient. (18C to 45C or 65F to 113F).
Time lapse thermograph of the first 10 minutes:
That was made snapping a photo every 10 seconds, and combining the frames with gif software. Next is what everyone is concerned with: POWAR.
It is very unstable, as many are aware. As such, a simple 30 second reading does not show the whole picture. Even the 1 minute sample above doesn't. Temperature plays a huge role in the output. So it is very difficult to pin down any succinct power output for this thing. I only ran a single 10 minute power test, since my meter does not log, and I enter data into a spreadsheet by hand. But here are the results.
Starting at 18C:
30 second average: 26mW
1 minute average: 40mW
2 minute average: 58mW
5 minute average: 57mW
10 minute average: 41mW
peak: 130mW
So a 30 second reading starting from cold would leave a user very disappointed, while a 2 minute reading starting from warm-ish could yield averages of >70mW and would leave a user delighted.
Each datapoint above is the average over 10 seconds. Best I can say is that power typically falls between 20mW and 90mW depending on on-time and temperature. :undecided:
I'm happy with it, overall. My smaller yellow (pictured way above) takes 20 seconds from cold to output any light at all, and averages <0.5mW, althought it averaged 3mW when I first got it. So this is a big improvement.
Equipment used:
FLIR E8 thermal imaging camera
Gentec TPM-310 laser power meter
Science-Surplus spectrometer
Tenma 72-6908 bench power supply
Payment was a pain in the ass. Both of my credit cards (in good standing) were declined by their payment service, and I ended up having to email them requesting a paypal invoice.
Size comparison with the CR2 model
Website beam specs claim 2mm and <1.5mRad. I measured the beam as ~2mm at aperture, and ~8mm at 11m which makes 0.55mRad. Not bad at all. Beam focus is not adjustable, by the way (at least not without modification).
My camera can't properly pick up the laser dot, so I didn't try. Beam profile is typically not Gaussian. Mode shifting happens often... every second or two while warming. Beam profile is always round, however.
IR output is negligible, and barely shows up on NIR camera. Estimated <0.1mW. Pump wavelength showed up on spectrometer as 807-808nm as expected.
Driver is linear. Site claims operation of 3.7V, but it regulates very well at 2010mA (+/- 5mA) anywhere between 2.6 and 4.5V. Note: 4.5V increases power dissipation over 3.7V and is probably not a good idea for long durations. Driver operates most efficiently at 2.6-2.7V. Unfortunately, that means if you wait until the laser goes out to recharge your cell, an unprotected lithium cell will be damaged from under-voltage.
Website specs instruct use no longer than 1 minute at a time, which is complete nonsense. Total power dissipation is roughly 7-8W, and a large chunk of aluminium can handle that without a problem. I left the pointer on for 30 minutes, and temperature rise topped out at 27C above ambient. (18C to 45C or 65F to 113F).
Time lapse thermograph of the first 10 minutes:
That was made snapping a photo every 10 seconds, and combining the frames with gif software. Next is what everyone is concerned with: POWAR.
It is very unstable, as many are aware. As such, a simple 30 second reading does not show the whole picture. Even the 1 minute sample above doesn't. Temperature plays a huge role in the output. So it is very difficult to pin down any succinct power output for this thing. I only ran a single 10 minute power test, since my meter does not log, and I enter data into a spreadsheet by hand. But here are the results.
Starting at 18C:
30 second average: 26mW
1 minute average: 40mW
2 minute average: 58mW
5 minute average: 57mW
10 minute average: 41mW
peak: 130mW
So a 30 second reading starting from cold would leave a user very disappointed, while a 2 minute reading starting from warm-ish could yield averages of >70mW and would leave a user delighted.
Each datapoint above is the average over 10 seconds. Best I can say is that power typically falls between 20mW and 90mW depending on on-time and temperature. :undecided:
I'm happy with it, overall. My smaller yellow (pictured way above) takes 20 seconds from cold to output any light at all, and averages <0.5mW, althought it averaged 3mW when I first got it. So this is a big improvement.
Equipment used:
FLIR E8 thermal imaging camera
Gentec TPM-310 laser power meter
Science-Surplus spectrometer
Tenma 72-6908 bench power supply
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