C
carulli
Guest
I have been searching around and I have found people saying that you can colimate a 808nm pump laser diode and I have found others that say that is nearly imposible beacause the beam is bar shaped.
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FrozenGate by Avery
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Re: Can I colimate a 808nm pump laser diode from a
Let's put it this way, you are never going to get a nice >90% circular beam. A bar pump diode is a series of 808nm emitters so they are essentially a bunch of small lasers. You can gather the individual beams together for burning or whatnot but you need some special lenses. The best way is to remember that diode lasers have a fast axis and slow axis divergence. To be able to control these uneven divergences requires lenses that focus in a single plane. Cylindrical lenses will allow you to have control over each axis. You set one parallel to the slow axis and one parallel to the fast axis. You can bring the laser light to a nice point if you calculate the focus in each plane right. The drawback can arise if the bar is very long as the cost of a cylindrical lens would be outrageous if it is large. To control the cost you could start with a spherical lens to gather the light close and use cylindrical lenses for fine tuning. Once you gather it together in a nice square of light you can pass it through a beam expander or collimator to control long distance divergence.
Let's put it this way, you are never going to get a nice >90% circular beam. A bar pump diode is a series of 808nm emitters so they are essentially a bunch of small lasers. You can gather the individual beams together for burning or whatnot but you need some special lenses. The best way is to remember that diode lasers have a fast axis and slow axis divergence. To be able to control these uneven divergences requires lenses that focus in a single plane. Cylindrical lenses will allow you to have control over each axis. You set one parallel to the slow axis and one parallel to the fast axis. You can bring the laser light to a nice point if you calculate the focus in each plane right. The drawback can arise if the bar is very long as the cost of a cylindrical lens would be outrageous if it is large. To control the cost you could start with a spherical lens to gather the light close and use cylindrical lenses for fine tuning. Once you gather it together in a nice square of light you can pass it through a beam expander or collimator to control long distance divergence.
C
carulli
Guest
Re: Can I colimate a 808nm pump laser diode from a
so what your saying is that the lense already on the green laser wouldnt work when adjusted. What is your recomendation for a cheap lense that works?
[edit]I am not after a circular beam, I am just after a beam that has a low divergence. A bar like beam would be fine as long as I could burn things at say 10 meteres.[/edit]
so what your saying is that the lense already on the green laser wouldnt work when adjusted. What is your recomendation for a cheap lense that works?
[edit]I am not after a circular beam, I am just after a beam that has a low divergence. A bar like beam would be fine as long as I could burn things at say 10 meteres.[/edit]
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Re: Can I colimate a 808nm pump laser diode from a
I killed a very good Leadlight about a year ago to do this. No, the green focus lens doesn't work right. As frothy chimp said, you get two different focus locations through the green lens, so at each you can only get half of the laser's power. Mine will burn right up close and at about six inches though, so it's cool.
I still regret killing the LL though.
carulli said:
I killed a very good Leadlight about a year ago to do this. No, the green focus lens doesn't work right. As frothy chimp said, you get two different focus locations through the green lens, so at each you can only get half of the laser's power. Mine will burn right up close and at about six inches though, so it's cool.
I still regret killing the LL though.
C
carulli
Guest
Re: Can I colimate a 808nm pump laser diode from a
so I take it a merideth module wont work.
so I take it a merideth module wont work.
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Re: Can I colimate a 808nm pump laser diode from a
it will work for close up burning but you won't be able to get any real distance out of it
it will work for close up burning but you won't be able to get any real distance out of it
C
carulli
Guest
Re: Can I colimate a 808nm pump laser diode from a
if that is the case then I will just keep my greenie a greenie.
if that is the case then I will just keep my greenie a greenie.
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Re: Can I colimate a 808nm pump laser diode from a
When I made my 808 "pointer", I put the LD into an Aixiz module and mounted that into a dead greenie. With fresh cells, it will go a little over 250 mW but it's hard as hell to focus. SenKats 808's don't have windows and I seem to get a better focus.
What others say about close range --- believe it.
Mike
When I made my 808 "pointer", I put the LD into an Aixiz module and mounted that into a dead greenie. With fresh cells, it will go a little over 250 mW but it's hard as hell to focus. SenKats 808's don't have windows and I seem to get a better focus.
What others say about close range --- believe it.
Mike