Focusing

So I got my yobresal laser (1w 445nm) and am goofing around with it... but i have a few questions about focusing. I know there are pretty much 2 main focusing "modes" 1. infinity and 2. focusing for burning (i heard this is called pinpoint?) Anyway i know how to infinity focus fine but im not sure about the focusing for burning because when I have the laser a foot away from the target (dark newspaper) pretty much however way i turn the ring... it seems to yield the same dot. Can anyone enlighten me on this? I searched the forums but couldn't really find an answer.

PS. i may be a noob but i am not stupid and i do wear goggles so no worries about that

Thanks

Well the dot size probably changes, just it's so bright your eye can't tell the difference.

maybe the goggles im using arent very good. although i can't light a match through them so they at least do something... maybe ill get some laserglow goggles and then try again

what goggles do you have?

don't really know, i bought them off someone locally. They look the same as the Eagle Eyes goggles that were talked about not too long ago.

weidmark said:

don't really know, i bought them off someone locally. They look the same as the Eagle Eyes goggles that were talked about not too long ago.

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Hmm doesn't help lol

Are you able to see the rectangular "dot" with them on?

Turning the focusring actually changes a LOT the dot size, maybe you are not turning it enough? It may require several turns.

weidmark said:

So I got my yobresal laser (1w 445nm) and am goofing around with it... but i have a few questions about focusing. I know there are pretty much 2 main focusing "modes" 1. infinity and 2. focusing for burning (i heard this is called pinpoint?) Anyway i know how to infinity focus fine but im not sure about the focusing for burning because when I have the laser a foot away from the target (dark newspaper) pretty much however way i turn the ring... it seems to yield the same dot. Can anyone enlighten me on this? I searched the forums but couldn't really find an answer.

PS. i may be a noob but i am not stupid and i do wear goggles so no worries about that

Thanks

Click to expand...

This is a very tricky thing to do...

First of all, you need to experiment with the entire range of focusing motion that your lens will allow you to do. As you start turning the lens clockwise or anti-clockwise, you will notice that the "pinpoint" will change position throughout the focusing range. But this does not necessarily mean that you'll have a pin point at the exit of the aperture and a foot from the aperture. In other words, you might never be able to focus your laser to a pinpoint in order to burn a magazine from a foot away because your laser's divergence, beam diameter, glass material, lens size and shape will have a drastic effect on the way your laser focuses through the entire range of focus. What I would do is fill a room with smoke, turn the laser on without goggles, point it towards the ceiling so you have a better view of the beam and avoid looking at the dot on the ceiling. Make sure your lens is screwed in as much as it can into the module and then start turning the lens anti-clockwise until the "pinpoint" is as far from the lens as it could possibly be. By doing so, you will be able to burn things from the greatest distance your laser will allow you to...

Have fun experimenting!

drummerdimitri said:

This is a very tricky thing to do...

First of all, you need to experiment with the entire range of focusing motion that your lens will allow you to do. As you start turning the lens clockwise or anti-clockwise, you will notice that the "pinpoint" will change position throughout the focusing range. But this does not necessarily mean that you'll have a pin point at the exit of the aperture and a foot from the aperture. In other words, you might never be able to focus your laser to a pinpoint in order to burn a magazine from a foot away because your laser's divergence, beam diameter, glass material, lens size and shape will have a drastic effect on the way your laser focuses through the entire range of focus. What I would do is fill a room with smoke, turn the laser on without goggles, point it towards the ceiling so you have a better view of the beam and avoid looking at the dot on the ceiling. Make sure your lens is screwed in as much as it can into the module and then start turning the lens anti-clockwise until the "pinpoint" is as far from the lens as it could possibly be. By doing so, you will be able to burn things from the greatest distance your laser will allow you to...

Have fun experimenting!

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A 1w laser inside without goggles seem like a very unsafe thing to recommend doing.

Please always where your safety goggles, would you rather attempt to focus your laser or have both your eyes?

udanis said:

A 1w laser inside without goggles seem like a very unsafe thing to recommend doing.

Please always where your safety goggles, would you rather attempt to focus your laser or have both your eyes?

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He could wear safety googles if he wanted to, but that would mean not being able to see the laser's beam. What hurts the eyes is the dot hitting a light colored surface, but it wont be bad for him if he's just looking at the beam. No harm done there...

Promoting use of a class 4 laser without safety glasses? Bad idea.

Lets quote everyone's favorite company...but surprisingly they have a lot of information on safety. You might want to give that a read drummerdimitri
Blue Light Hazard

udanis said:

Promoting use of a class 4 laser without safety glasses? Bad idea.

Lets quote everyone's favorite company...but surprisingly they have a lot of information on safety. You might want to give that a read drummerdimitri
Blue Light Hazard

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You are giving good advice, but at the end of the day, the user decides whether he wants to wear the goggles or not. He is asking for help on how to focus his lasers' beam for distance burning, so I gave him the solution. Arguing that you should wear glasses is irrelevant here because it would render my solution useless. You can advise him to wear safety glasses all you want for pointing around with a 1 W blue laser indoors, but don't criticize my recommendation because it does the job and thats what the OP is looking for. He is totally free to ignore it for safety reason if that means anything to him or he could just carry on with what I suggested he does. The choice is his in the end...

drummerdimitri said:

You are giving good advice, but at the end of the day, the user decides whether he wants to wear the goggles or not. He is asking for help on how to focus his lasers' beam for distance burning, so I gave him the solution. Arguing that you should wear glasses is irrelevant here because it would render my solution useless. You can advise him to wear safety glasses all you want for pointing around with a 1 W blue laser indoors, but don't criticize my recommendation because it does the job and thats what the OP is looking for. He is totally free to ignore it for safety reason if that means anything to him or he could just carry on with what I suggested he does. The choice is his in the end...

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If your recommending something to someone that is generally unsafe, people should criticize your idea.

Have you made sure that the lense IS focusable and not just a set lense that your turning ???

Well I'm am guessing he has this laser
http://laserpointerforums.com/f39/1-1-2-watt-445nm-lasers-cheap-180-a-54005.html

Ahh, in that case, make sure that the focusing ring is screwed on properly to the lense so that your not just turning the ring