Hades vs electrical tape

Spinoff from this thread http://www.laserpointerforums.com/forums/YaBB.pl?num=1187484914

Laserglow.com Hades 808 1.1watt handheld Laser.


http://208.219.69.31/laser/hadestapesm.wmv (350kb)

that's the weather channel in the background if anyone is wondering.
( watching the Hurricane Dean info's because of my job )

It can cut electrical tape instantly almost as fast as you want to wave over it.
This is a bare 808 diode so the diode ( and all bare diodes ) outputs a line that becomes a rectangle as it diverges.

Range on this shot is about 2 feet away.

Nice display !!! Does the IR need a special lens to focus like that ?? My 250 mW -808 is built in an Aixiz module and doesn't focus like that.

Mike

no lense, it's actually not very focused at all. right out of the aperture the "dot" is a square, about 1mm x 1mm. if you pause the video right after the title you can see the square dot very well.

If i did focus this guy down tiny, it would be a monster. The foam I usually use to test burning stuff ignites. So does paper, even white paper. That does make it easier to see what I'm doing though because the illuminated area glows like embers..

I might try that -- I noticed it is square but I thought it focused that way. I got IR glasses last week to help protect me....

Mike

Really makes me want one of those >.>

Excellent work Aseras!

Hmm... IIRC theres a guy on ebay with 1 watt 808nm diodes. Prolly will get one of those eventually, then a x85, and my collection will be complete! For a while anyway...

Aseras --

I took the lens out of my Aixiz 808 module and the beam comes out like a red -- a BIG blurred rectangle. POOP -- I put the lens back in.Your 1 watt must be a different style like maybe a C mount.

Mike

Hemlock Mike said:

Aseras --

I took the lens out of my Aixiz 808 module and the beam comes out like a red -- a BIG blurred rectangle.  POOP -- I put the lens back in.Your 1 watt must be a different style like maybe a C mount.

Mike

Click to expand...

I believe Aseras' laser is the same. When you get into high power multi-mode diodes like that, its just expected to have horrid beam specs and an ugly dot profile. When you collimate that big blurred rectangle though, like with that 1W, it can end up looking more like a circle from distance. Up close its still rectangular in shape though.

wow dudes, can this be focused like a regular greenie, surely there must be a way! its would really rock!!

I doubt it... I think the MCA crystal will turn it into a nice beam... hence why DPSS lasers can get very powerful and still have a very excellent beam spec (rivaling gas lasers in some cases).

Needless to say though, Aseras, your laser is NUTS! That is just amazing! Have you tried wood-burning with it? That should be fun! Is you can get the dot fine-tuned anyway... :-/

Thanx for sharing;
DDL

Hey Mike, let me rephrase that, there is a lense to focus/colliminate the diode output. I'm not however using another lense to focus the laser down anymore than what is coming out of the laser.

A bare diode will come out as a line and it diverges so quickly you do get a huge big rectangle. Some diodes like reds have a "lense" added to the face of the diode to correct the output to more of a dot. Most 808 diodes though are intended to pump a crystal set so they have no such thing since once they pump a crystal the crystal will determine the tem mode. direct diodes don't really have a mode, they are more like overpower LED's with coherent light output.

The tem modes we are used to with dpss lasers and gas lasers are a function of the laser or electricity pumping the diode or gas. the crystal or gas reacts to the energy being added and generates another kind of light. if you don't put the energy or light in the right place or you put too much or too little in the the reaction isn't stable and you get fluctuations. you also get fluctuations due to heat changing the alignments and optical distances. This is what causes mode hopping in dpss and gas lasers.

Diodes are completely solid state, so if you overpower them they burn up, at the electrical terminal coming in, the planes split or you get catastrophic optical damage on the face of the diode where the output gets so high it melts or cracks it and then you get a "led"

Aseras --

I sure did misunderstand -- I thought you got that beam from the diode with no lens !! I'm using the Aixiz glass lens unit now - I may try the plastic to see if my focus improves.

Mike

Direct diodes may not have transverse modes like we're used to talking about in greenies, but you still have to consider the longitudinal modes. There's a world of difference between trying to use a single mode versus a multi-mode diode laser in a lasershow projector, portable laser, etc.

Pseudo ---

I should have told what I did. I removed the diode pump and driver board from a 15mW greenie and stuffed it into an Aixiz module to get an 808 !!!
Focusing it is a strange circuis of Huh's? ............ I know some glass doesnt work well at IR.

Mike

What problems were you having with the lenses? Perhaps you need to use a stronger lens. The divergence straight out of the diode will be huge, and a lens won't bend 808nm as much as it would with visible light, so you end up needing a pretty strong lens to get the output roughly collimated.

From what I can tell the lense in the hades is very strong. it's quite thick in the middle and has almost no edge. Like a circle cut in half, but flatttend just a bit. Can't really tell much since it's buried back inside the aperture, and I don't have the tools or the need to take it apart.

I'm still scratching my head on trying to improve the beam specs on the 700mW IR laser I bought from Pseudo. It burns like crazy, but I want to make an adjustable focus laser out of it.

most standard lenses don't work well, or have minimal impact on the beam. I've tried every lens that I received from the "Optotronics lens kit" and no dice. I think that IR isn't altered as much by the standard lenses due to the longer wavelength.

I am also trying to figure out the GRIN lens approach. Any help would be appreciated.