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ArcticMyst Security by Avery

Focusing for illumination, not a beam.

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Okay, now I have another question. I want to use a laser diode for illumination. Basically more focused and powerful than a flashlight, but less focused than a pointer.

Okay, so just run the focus out on your lens, right? Well, there is one more thing. The module containing the diode can be rotated one or so degrees to aim it. This is inside a sealed box (waterproof) and I need the to be able to adjust the beam size (focus) from the outside.

Like how the aixiz housings can be focused with the knob, only the diode will not necessarily be inline with the lens.

Is it possible to alter the focus of a beam coming in at an odd angle without altering its direction? It doesn't seem physically possible, but then again, I don't know much about optics.:thinking:

I was thinking maybe focusing the light into a beam, aiming that(it will only be "aiming" about a degree) beam through another lens that is attached to the outer case and can be focused. But again, it seems like that would alter the beam's aim...

Does any of this even make sense? I'm having a hard time explaining...
Thanks in advance for any help!
 





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What your wanting to do would be kind of difficult. It would probably be much easier to buy a focusable waterproof laser from rayfoss, but I dont know how well it would work as a flashlight...
 
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Well, it needs to go inside of a compact unit I am building, so that limits it to a lens assembly that I can build with small components.
 
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I'm confused by what you are calling "aim." If the beam leaves the aparature at a wierd angle you might be able to use a lens to correct that, but I doubt it. A convex lens will only make the beam expand faster, it won't make it turn or anything. If you cannot get to the lenses inside, I would just mount a lens to the outside of your laser. It would increase the beam size a lot depending on the focal length of the lens you use. A closer focal length will make a bigger spot faster.
 
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All of the laser components and electronics will be in a sealed, waterproof box. The illuminator can be aimed about a degree to alter where it is pointing. The focus for the illuminator needs to be able to be adjusted from the outside of the sealed box. To do this I was just going to have the focusing knob with the lens in it screw into the box.

The problem is, if the focusing lens just screws into the box, how do I aim it by moving parts inside the box?

I hope that makes a little more sense...:thinking:
 
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If the beam is going to move, then you will need a lens with more surface area for the beam to go through.

Does that make sense, I don't know how else to explain it :D
 
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Yes, that makes sense, but if I run the focus in and out, then wouldn't that change the point of aim? Or is there some kind of fancy lens I'm not aware of...?
 
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We could help you more if you told us what your actually going to be using it for...
 
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I think what he's sayingis that there will be an enclosure that is, for all intents and purposes, clear and sealed, with the internal parts able to swivel about inside of the enclosure. He probably wants a lens that will cover the sweep of the laser and have approximately the same defocusing effect.

I'm thinking a bigger lens will achieve just that. Problem is, it will also affect the aim adversely. and inversely :D

How about a solenoid with a lens attached, and the whole thing mounted inside the enclosure? it swivels with the laser, so it stays stationary relative to it, and then when you want to defocus the laser, the lens pops up in front of the beam. Got room for that?
 
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Infrared illumination for night vision. It will be mounted on a rifle, so it needs to be light, compact, and weatherproof.

Here are some links to pictures of similar units to what I will be making:
http://tnvc.com/images/item_pages/large_pics/laser_systems/dbala2_7.swf
http://tnvc.com/images/item_pages/large_pics/laser_systems/atpial_3.swf

You will notice on both units the IR illuminator is on the left side of the unit. It can be adjusted with just your fingers. There are also aiming knobs.

I am considering having the focusing lens move with the diode assembly, IF I can find out a good way to have it seal...
 
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I think what he's sayingis that there will be an enclosure that is, for all intents and purposes, clear and sealed, with the internal parts able to swivel about inside of the enclosure. He probably wants a lens that will cover the sweep of the laser and have approximately the same defocusing effect.

I'm thinking a bigger lens will achieve just that. Problem is, it will also affect the aim adversely. and inversely :D

How about a solenoid with a lens attached, and the whole thing mounted inside the enclosure? it swivels with the laser, so it stays stationary relative to it, and then when you want to defocus the laser, the lens pops up in front of the beam. Got room for that?

Yes, you got it:yh:That's what I was worried about with the lens. Having the lens attached is looking more and more like my only option. I wonder how they do it?
 
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I want to use a laser diode for illumination... powerful than a flashlight

Not happenin', dude. 200mW of red is ~14 lumens. A tiny 8-led flashlight is brighter. Even 200mW of green is a mere ~120 lumens which pales in comparison with a high power LED flashlight (900 lumens available at DX for under $50.)

Lasers are good for many things. General illumination is not one of them.
 
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~50mw IR diodes are used for illumination for the two units I posted pictures of. They are very bright seen through a NVD.
 
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50mW IR diodes use about .15W of power. IR LEDs have similar efficiencies, so a 3W IR LED should give as much light as a 1W laser diode. It will be FAR cheaper, FAR safer, and more robust.

First result from ebay
 

Benm

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I suppose you might need more focus in some situations though, like illumination for a sniper scope. When using IR based night vision you don't need that much light anyway, so it could make sense.

I dont see the whole waterproof/adjustable thing though... perhaps its best to draw a diagram of what you want it to do.
 
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LaserGuns,

Are you looking for something like the ND-3 laser designator?

My brother has a ND-3, and it works great for night time illumination with binoculars or a scope. It is only 18mW. There is a new model ND-3X50 that has 50mWs.

It works great as night vision for coyotes or hogs.

These units seem rather pricey for the power of the laser.

Hopefully someone will come out with another model.

I would like to build one with a more powerful laser, but I am knew and will have to study before I attempt that project.
 




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