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Just arrived: O-Like "400mW" 405nm

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There's no way your laser can draw only .5 amps, could there be something wrong with your reading? Even O-like says these lasers are supposed to be in the 1-2A range, for example these are the specs for the 400mW Green:

Wavelength: 532nm
Output Power >350mW
Pump diode 2.0W
Dimensions: Φ24mm×190mm
Transverse Mode: TEM00
Operating Mode: CW
Stability 5%
Operating Current 2A
Beam Diameter: 1.5mm(at aperture)
Beam Divergence: 1.5mRad
Duty Cycle: 100 seconds on, 60 seconds off
Power Source: 18650 lithium Batteries ,"+" towards tail cap
Operating Temp.: 10~ 35℃
Expected Lifetime: >5000 hours
Warranty: 6 Months (not included man-made broken

As you can see "Operating Current 2A", and my 405nm pulls around that same current, it fluctuates between 2.0 and 2.3, and sometimes reaches 2.6A.

My green however, pulls from 3-3.3A!

-Sal
Actually, the diode is an IR pump diode (hence, Diode-pumped part of DPSS) that emits light through crystals that change the wavelength to be green (very very very terrible explanation). The efficiency of the green light (if it is a high quality laser) will only be about 20%. So a very good green laser that has an IR diode that is 2W will be about 400mW: since that laser isn't the highest quality out there, it makes sense that it would be a little less than 400mW (but still around that output). The blu-ray diode is much more efficient than a green laser, since it doesn't need the crystals.
The 445 diodes don't use crystals so when you have the current at like 1.1A, it outputs ~1W. The blu-ray diodes have about the same efficiency as the 445 diodes.
That's what I got out of research on here: read posts 1 and 4 of the link:
http://laserpointerforums.com/f54/dpss-vs-diode-laser-advantages-57544.html
 
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Arshus

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I knew how DPSS works, and that our 405's arent DPSS, but I didn't know about the 20% efficiency and about the current, thats very cool thank you!

So are you saying that its normal for a green to take more current than a direct diode laser?
 
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I knew how DPSS works, and that our 405's arent DPSS, but I didn't know about the 20% efficiency and about the current, thats very cool thank you!

So are you saying that its normal for a green to take more current than a direct diode laser?
Yes. The reason green lasers take more current is because the IR diode has to draw so much current that it can be powerful enough to overcome the inefficiency of the crystals and still put out the 400mW (or however much it is supposed to) of 532nm light.
473nm lasers are the same technology but different crystals. It is more difficult to align the crystals and keep them in the correct temperature range for this wavelength which is why 473nm is such an expensive (and compared to other lasers, not very powerful) wavelength. They aren't nearly as powerful because they have like 10% efficiency for the same power input and IR diode output as 532nm.
 
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Arshus

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I see, however dont you think your readings of .5 amps and mine of 2+ amps are too far apart to be correct? I think yours has to take more than .5 amps, that can't be right.
 
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I see, however dont you think your readings of .5 amps and mine of 2+ amps are too far apart to be correct? I think yours has to take more than .5 amps, that can't be right.
Well the battery life on mine is really good. Way too good to be pulling that much current. But idk, it doesn't really matter. lol
 

RA_pierce

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I knew how DPSS works, and that our 405's arent DPSS, but I didn't know about the 20% efficiency and about the current, thats very cool thank you!

So are you saying that its normal for a green to take more current than a direct diode laser?
Actually, IR and red diodes are much more efficient than 405nm & 445nm.

For example, a 1.2W 808nm pump needs 1.8-2.2V & ~1.2A for 1W output. That means it consumes 2.16-2.64W. Since 1W is output as light and about 1.6W is dumped as heat, the diode's efficiency is a bit under 50%.

On the other hand, a 445nm diode consumes 4.2V & 1.2A for ~1W light output. That's 5W consumption. 1W is light and 4W is heat. That's ~20% efficiency vs. the 808nm diode's ~50% efficiency.

Getting to the DPSS process... the conversion efficiency can vary from <20% to ~30%.

So what this all means is that the entire DPSS process is less efficient than direct diode lasers, but the pump diode is actually much more efficient than 405nm and 445nm diodes and consumes less power with more light out.

When determining the efficiency you have to include the forward Voltage (Vf), not just the current consumption.

Here are some typical values for diode Vf at normal operating current:

405nm: 6V
445nm: 4.2V
635nm: 2.2V
655nm: 2.5V
780nm: 2.0V
808nm: 2.0V
 
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Napalm101

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Well i've seen videos on Youtube.

One guy mentioned his 405nm Diode :
"The diode drive current is set at 400mA and I tested this on a Laserbee I at 485mW"

Another guy mentioned he was getting 580mw : "Micro Flexdrive v5 @ 410mA"


So i'm guessing our mA should be around 350mA for current upto 500mA depending on the effeciency and what driver they used.

it will definitely not be 2Amps or even 1Amp



Another usefull Pic to check out :
http://farm5.static.flickr.com/4118/4823492235_ee4d594ae1_b.jpg
 

RA_pierce

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Well i've seen videos on Youtube.

One guy mentioned his 405nm Diode :
"The diode drive current is set at 400mA and I tested this on a Laserbee I at 485mW"

Another guy mentioned he was getting 580mw : "Micro Flexdrive v5 @ 410mA"


So i'm guessing our mA should be around 350mA for current upto 500mA depending on the effeciency and what driver they used.

it will definitely not be 2Amps or even 1Amp



Another usefull Pic to check out :
http://farm5.static.flickr.com/4118/4823492235_ee4d594ae1_b.jpg
Highlighted in green...

So are you guys trying to figure out what normal current draw should be from the battery or current at the diode?

Remember that the driver will consume power, too.
If it is a boost driver it will pull more current from the battery to boost the voltage.
As the battery drains the driver pulls even more current.
 
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Arshus

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Interesting, I wonder what current a green like this usually draws? .5A or more like 2A?
 

RA_pierce

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Interesting, I wonder what current a green like this usually draws? .5A or more like 2A?
I have a 40mW pen that draws 0.3A.
My 175mW green pen draws 0.5A.
My PGL-III-C 400mW pulled 2.1A IIRC.
 

dinners45

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Ok guys the following will be a review of the O-like "400mW" 405nm Adjustable & Waterproof laser:

This laser came friday and is a little gem of a laser.



As you can see it came intact from Hong Kong with a nice little box with foam cutouts and to my surprise an Ultrafire Protected 2800mAh 18650 lithium battery.



As you can see the host is beautiful and has no stratches or blemishes and the threading is exellent. The tail cap screws on very nicely and snugly and has a rubber retention ring. Both of the laser's contacts are springs but with this unit its always "+" end of the battery towards the tailcap. There is absolutely no shaking once the battery is loaded in and the tail cap screwed tightly on. This laser has a very easy to operate rear clicky, which a very nice dustcap installed.



This laser is an exotic purple beauty. Very nice tight beam when focused for long range, and a clearly visible purple beam, these pictures are taken with an I-phone camera, with no added effects, no fog or smoke added.



As you can see I provided a picture of the laser's dot filtered through my goggles. It is a nice oval at close range and a more circular at longer ranges. This laser has no artifacts around the dot, which is very nice. It also helps me prevent identity theft by quickly, easliy and permanently redacting any documents or receipts before throwing them away.

And now for the power measurments:

This laser is rated at 400mw; however is capable of so much, much more:


For this run the laser started out at about ~510mW and quickly exceeded 560mW, reaching a peak of 568mW. As you can see from the laser's upward trend, it would have easily reached 600mW if left running for longer than the 75 seconds metered here, but as susie says:



I didn't want to keep it running for longer for fear of affecting the diode's lifespan as these lasers have a 60/90 sec on-off duty cyle.

So thats it for now, I hope you have enjoyed the review, please post a response with any additional questions, pictures or tests you would like me to run :yh:

Regards,

Sal
Thanks for your review, i just got mine today,(14 days, 2 weeks or one fortnight) after ordering, just to let everyone know my O-Like 400mw 405 is fantastic, came with the Ultrafire 2800 battery also, WOW I'M LOST FOR WORDS.
 

Arshus

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Ordered on 1/2/11, and received 1/28/11, so it took approx 4 weeks to arrive, granted it was during a chinese holiday.

-Sal
 




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