new DX lasers

[Hemlock_Mike]

My new "cheap" 50 mW pointer arrived from DX today
It looks like all their other pointers 5 to 200 mW.

Using the Alkie cells provided: Total Peak Power out: 42.2 mW
IR Output: 0.72 mW

Using new e2 cells: Total Peak Power Out: 44.6 mW
IR Output: 0.76 mW

Power quickly drops to about 38 mW and I popped a black balloon at 2' with it.
All their other pointers I've gotten exceed rating - this on does'nt but for $26 ---


Mike

 

[Benm]

For how long does it maintain that 38 mW or so?

It's a bit below spec, but if it can maintain that for at least a couple of minutes, i dont think $26 is bad value at all. And while you have that laser around, could you pop in a couple of NiMH's and see what kind of power you get from those?

 

[Hemlock_Mike]

I'll have to see if I have any NiMH cells in aaa.  I use e2 for all my pointers...

Mike

Several hours later deep in the lab ----- I charged a pair of aaa NiMH cells.
Power out : 31.7 mW -- This is a cold blooded little sob .. It wants to be warm - about body heat to get up to power.

 

[Benm]

Thanks for testing!

I've noticed the 'cold blooded' thing on other DX lasers too, need to be hand warmed before producing good output. Then again, i guess its just the nature of green DPSS lasers.

At some point i tried cooling a pointer in the fridge in a ziplock bag to about 7 degrees C or so, at which point no green light comes out anymore. Interesting thing about is that you can actually see red light from the pump diode spewing out.

 

[Alias777]

Thanks for testing!

I've noticed the 'cold blooded' thing on other DX lasers too, need to be hand warmed before producing good output. Then again, i guess its just the nature of green DPSS lasers.

At some point i tried cooling a pointer in the fridge in a ziplock bag to about 7 degrees C or so, at which point no green light comes out anymore. Interesting thing about is that you can actually see red light from the pump diode spewing out.

...Did you look down the barrel?

 

[Benm]

Hehe.. i'm not THAT stupid, at least i hope.

Just pointed it at a sheet of paper and could see the red light reflecting off of that. Considering the apparent brightness and wavelenght (must be 808 nm, right?), looking down the barrel might have fried at least one eye.

 

[SenKat]

Yes - do not EVER look down the barrel with the batteries in the laser ! GAH ! That would be a horrible way to stop reading on here You will not even feel the pain of your retinas being fried - it will jsut happen, and then you will wonder what your new guide dog actually looks like !

G !

 

[Hemlock_Mike]

Behm -- The output frequency of LD's is somewhat temperature sensative. At that temp, the LD may have been lasing around 803 nM and not exciting the MCA. With no green, you can see the deep red.

Mike

 

[Benm]

I know.. but i was just a bit surprised by the brightness of it. 808 or 803, its both really on the border of vision.

I guess this also says something about the absence of (proper) IR filtering in these lasers. The good thing is that the red light comes out in a flashlight-like broad pattern, so its probably not very dangerous at any range but point blank.