Mitsubishi ML520G71...Red Holy Grail or Flashlight Fail ??

[Solarfire]

so in general, we are talking about 1.5-1.6 divergence with 35% loses for the best farfield so far (o-like and prisms)

Your math is not quit right, its 45% loss with the O-Like and prisms.

[LaNeK779]

yes, your right about the 45%. maybe i didn't want to believe it myself

Frank could you try the two prisms like this |_\ |_\ (like two individual prisms and not an anamorphic prism pair) instead of the usual setup?
maybe this way you could get higher magnification. of course, the beam will turn maybe more than 90 degrees after this


maybe we should start looking for an aspheric collimator with an FL of higher than 8mm and a diameter + numerical apperture big enough to limit those loses?

[kiyoukan]

Based on Solarfire's results i would like to see that beam folded and what results that would show.

[Solarfire]

Well I just did a couple more setups, a little tweekin and it’s actually not bad, especially for 70 bucks.

With either a short or long FL collimator, in both cases a cylinder correction of approximately 1:4 would probably give good results.
Prisms are best (easiest) if you're satisfied with a 1.77mrad beam with resonable losses.
The O-like with prisms brings a beam with 1.77mrad divergence, 4mm x 1.5mm at the prism aperture and a far field of 9mm x 21mm @ 11m.
The beam is bright, even only @ 400mA/190mW after correction optics, use safety glasses.
These teste were done @ conservative datasheet power levels.

I’ve got some of drlavas cylinders that I may try tomorrow.
The camera can’t correctly capture the way the beam profile really looks. Well shit, I’m gonna use em... Add a little 658nm to give a little more depth. The scanner aperture will clean up the rest.

Anyone got an Optima and a 1:4 set of cylinders lying around?

I actually should be working on my TEC/LD-driver, got carried away! Shit….

Oh well, life’s a bitch…

[mixedgas]

Best I got a year ago was 55% loss. Your results were comparable with mine. My problem:It is very difficult to get the collimation lens close enough to the diode to matter. DR Lava's lenses were useful for this diode.

I'll see if I can dig up the beam shots.

Steve

[logsquared]

Everybody loves some pictures

Current .5Amps
Collimator thorlabs C330TME-A

Telescope -19 PCV and 95 mm FL PCX

Power before tele 380mW at .5A

After tele 315mW (should be better but the coating on the PCX lens is killing some power)

After .140" pinhole 194mW Hard to see but spot is .5 inches at 39 feet for a .77 mRad divergence.

[mixedgas]

Logsquared, Would you mind seeing how badly that clips on the galvo mirrors at 20 degrees optical? Add in some distance to simulate the dichro mirrors? Laser media test pattern, please.

Steve

[mixedgas]

I know you said others have tried this before. Sometimes it takes someone else working it in a way that escaped other people. Let us hold back a night out with the guys, knocking back some brews at the bar and instead spend it on some cheap red. When stuff like this comes up, that is when I have fun. I like trying to figure something out. Steve, again, you rock... but ease up a bit! [/QUOTE]

Ok, The goal was many many, many, graphics units The customer had a fixed price goal, needed a specific power level, and it needed to fit in a small box.. So when these things were beaucoup expensive, the other part won. Now that they are down to 70$, you can afford to throw away some power. The customer could not see throwing away 50% of the power before they even started down the optics train .

What I'm seeing is still at about parity with a Opnext in cost, by the time you buy the three lenses and pinhole and mounts, for ~200 mW per beam. I did not know the price had dropped. I can see that the diode has improved a bit. It is still consuming considerable real estate to get a good beam with these.

I'm not above admitting that for some folks these will be very useful now that the price is down. The spot sizes so far are similar to what I achieved a year ago.

The fun part will be, for many users, getting used to tuning their amps for bigger mirrors and smaller scan angles.
It will be interesting to see if mirror stock can be ordered in the right thickness for bigger mirrors for existing Asian galvos. :-)
It would be a real trick to knife edge more then 2 of these onto standard mirrors.

Steve

[mixedgas]

Quote: He may have been referring to a single mode LD for a source, though.[/QUOTE]

Nope, he has what we are discussing. Believe me, I know.

Steve

[absolom7691]

What I'm seeing is still at about parity with a Opnext in cost, by the time you buy the three lenses and pinhole and mounts, for ~200 mW per beam. I did not know the price had dropped. I can see that the diode has improved a bit. It is still consuming considerable real estate to get a good beam with these.

I have a lot of these optics lying around, collimators, 5 sets of prism pairs from other laser tear-outs.... for me this would be alright, but yes, for others that would need to purchase these additional optics, you definitely have a point, the Opnext cans might be the way to go (headache wise).

It would be a real trick to knife edge more then 2 of these onto standard mirrors.
Steve

Realistically, I can't see any more than a quad... knife edging the pairs and then combining them. Anything more... fat-ass beam! (____) lol