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Casio 445nm Limits??

Joined
Sep 24, 2010
Messages
34
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8
Whats the limit on this diode? I've seen 1.6w reviews. How far can we push it? I'm curious what it could do if it was only on for 10-15secs and had a cooling fan on it.
 





But, this is his method of doing "research"... by asking people to do his "work" for him.
Genius! :banghead:
 
I guess we won't know until we kill one. My 1.6 Watt build has been one for at least 2-5 hours. No signs of degradation yet.
 
Are there any ready made drivers that can push 2A with out melting the driver its self?

After reading up on the durability of these diodes, I wish I had Dr. Lava set my flevdrive to 1.5A instead of just 1A.
 
Common lab source should be able to push it to 2A without problem.
 
Are there any ready made drivers that can push 2A with out melting the driver its self?

Make a current sink drive, it's the more easy system, and power it with 7,5V or similar.

3355-himnl9s-crazy-generical-lab-type-current-sink-analog-modulable-laser-diode-driver-p.jpg


Next week i have to build some of them for a friend, and i probably will end making some more (always doing this, for batch builds, "just-in-case" safety policy :p)

So, if you're not in hurry, for the end of the next week i will have some extra ones that i don't use.
 
@Spartan X

If you are using a flexdrive, you can just turn the pentiometer to its maximum setting. Just make sure you have adequate heatsinking on the diode and driver.
 
Make a current sink drive, it's the more easy system, and power it with 7,5V or similar.

3355-himnl9s-crazy-generical-lab-type-current-sink-analog-modulable-laser-diode-driver-p.jpg


Next week i have to build some of them for a friend, and i probably will end making some more (always doing this, for batch builds, "just-in-case" safety policy :p)

So, if you're not in hurry, for the end of the next week i will have some extra ones that i don't use.

Nice HIMNL! Do you know about how fast this can be modulated?
 
There are other reasons you should take into consideration when setting the diode current rather than just the capabilities of the diode.

Personally I'm more worried about the driver. The efficiency, at best, of the Flex or Boost Drives is about 90-95% which may seem pretty good. But think. 1500mA at about 5v is over 7 watts! That means than the driver is dissipating well over half a watt as heat. That is alot for those tiny components. Furthermore drivers often never get heatsinked properly in handheld builds.

Also the battery! If the diode is chewing up 7 watts than can the batter supply that plus the wattage going to heat by the driver!? A good quality LiMN cell probably could but those cheaper Ultrafire and Trustfire cells will have a hard time keeping the voltage up under such a drain. Or the clicky switch. Those cheap clickys wont last, it's too much power.

Unless you want a duty cycle of <30 seconds, for most handheld builds IMO, they should be run at about 1A diode current max. Otherwise you'll have issues with short duty cycles and battery life.

And besides, side by side, 1.5W is only slightly "brighter" than 1W. Unless you get your kicks by burning stuff all day, what's the point?

Just my 2 cents/rant

-Tony
 
Mine hits 1.1W and its scary. I dig the need to get the highest power, but as Tony said, you sacrifice your duty time, and you chance frying the driver, battery, or even diode from the heat. Keep it around 1W, and buy a 405g1-2 lens. It will give you ~300 more mWs.
 
Nice HIMNL! Do you know about how fast this can be modulated?

Not really sure ..... i made some for friends, and one of them use it with around 15 or 20KHz TTL without problems, for drive an IR diode in a plotter, but i have never tried to reach a limit with analog modulation, so can't say what's the maximum frequency, sorry.

Need to take a quick photodiode, a sine wave frequency generator and an oscilloscope, for do some tests, but at the moment i don't have phisically the time for do that ..... or, if someone have a working scanner, i can imagine a system, without having lab equipment ..... using it in a scanner, drawing a circle and using the same signal of one of the axis for modulate also the intensity ..... this must give you a circle that go from the minimum luminosity on one side, to the maximum on the opposite side ..... increasing the frequency, when this start to become unstable, this is the modulation limit .....
 


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