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Something wrong here?






This particular diode is a quite nasty rectangle indeed. It is a Mitsubishi 638nm diode, if you are interested- there are ways to correct the beam, but I don't think you will have nay luck doing it in a handheld.
 
Thanks for your reply crazy... wouldn't harm to take a look :)

Yeah it is pretty nasty to be honest, i think its a multimode, because if i push the button twice it flashes.

I suspected it was no abnormality the diode looks pretty different from the likes of 445's ect.

The unit itself seems pretty work friendly, i had it in bits and put it back together again with ease.
 
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Yep, those diodes are multimode for sure. Pretty nasty to be honest.There's nothing wrong with it though.
 
No problem that I can see, that "rectangular" dot is normal for lasers in these wavelengths.

Heck, my 635nm Libra has the same "dot".
 
Tha Greenlander said:
No problem that I can see, that "rectangular" dot is normal for lasers in these wavelengths.
Click to expand...
Its not the wavelength that determines the shape of the dot.

Heck, my 635nm Libra has the same "dot".
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Like DJNY said, yours does not have the same dot like the OP's. I bet you haven't yet seen in person how bad the dot of multimode red is.
 
To add to what DJNY is talking about for those who don't know, multimode vs singlemode. These are not power supply "modes" pulsing, continuous wave etc.

This is a property of the laser cavity, where in multimode the beam traverses back and forth in a somewhat non-linear fashion(loops). As opposed to singlemode where the beam stays very linear/straight within the resonant cavity.

Singlemode lasers don't diverge very much because of this, and give you a tighter beam. They are preferable when beam quality is the issue.
 
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MrJohnston said:
Thanks for your reply crazy... wouldn't harm to take a look :)

Yeah it is pretty nasty to be honest, i think its a multimode, because if i push the button twice it flashes.

I suspected it was no abnormality the diode looks pretty different from the likes of 445's ect.

The unit itself seems pretty work friendly, i had it in bits and put it back together again with ease.
Click to expand...

He means the Diode is multimode, not the driver (which is also multimode) The flashing comes from the driver, as the driver has a controller that allows the output to flash.

However, a multimode DIODE is different. All high powered diodes are multimode, and each mode adds lasing "layer".

With each mode, the divergence gets worse...

Hope that helps

:beer:
-Matt
 
A 800mw 638nm for under $200? Usually olike is pretty on point. Sounds like a pretty good deal if it's onspec
 
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