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Lets Collimate a C-mount diode ok!

sbdwag

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Im looking for options (that do not take a degree in optics) to collimate or focus a C-mount 808nm diode.

Seems like the easiest way would be to purchase a Optic system designed specifically to collimate a high powered laser. Surplus shed has some and Chris has a Missle laser optics system for sale that will do the job.

But the question without some eleborate machining How do I position that optics module concentric and at the right distance from the diode. The best answer I can come up with is machine a round sink for the diode, step off the mounting hole so the diode is in the center of the sink, thread the outside and make a adapter to mount the optics concentric to the sink.

This opens up another pandora box. How to I protect the cathode from positive case of the diode and route it thru this mounting system.

Of coarse If I knew alittle about optics I could just float a PCX lens in front of the diode and then route it thru a cylinder lens. But the question is what focal length PCX lens and cylinder lens and how close to the diode and how do I determine the optimum focal lengh for converging the slow and fast axis together to get the best collimation. C-mounts are just very poorly suited to the novices like me.

Many many questions that google has yet to give up. Its especially hard to find any information on C-Mount Laser diode systems.

Any help or links would be appreciated just point me in a good direction.

regards
sbdwag
 
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ElektroFreak

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To me one of the greatest alluring parts of the laser world is the fact that from a hobbyist standpoint there is much that hasn't been documented in places that are easily found. It's magical juju as far as 99.9% of the population are concerned. A huge amount of laser-related knowledge either requires heavy mathematics and college courses or are trade secrets and most of the time both.

There is no simple answer to your question except to buy a set of lenses with known parameters for each and calculate how you want them laid out. Math. That's the professional way.

There's also trial and error, which is the only way to get it without a bit of math. If you have a large selection of coated lenses and movable mounts, you can experiment with various distances and configurations until you have one that works and then design a block around that configuration.

Check this link out starting at page 215. It's a limited preview so it's missing a page here and there, but it should help you understand some of the principles. For a great read, buy the whole book.
 
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To me one of the greatest alluring parts of the laser world is the fact that from a hobbyist standpoint there is much that hasn't been documented in places that are easily found. It's magical juju as far as 99.9% of the population are concerned. A huge amount of laser-related knowledge either requires heavy mathematics and college courses or are trade secrets and most of the time both.

There is no simple answer to your question except to buy a set of lenses with known parameters for each and calculate how you want them laid out. Math. That's the professional way.

There's also trial and error, which is the only way to get it without a bit of math. If you have a large selection of coated lenses and movable mounts, you can experiment with various distances and configurations until you have one that works and then design a block around that configuration.

Check this link out starting at page 215. It's a limited preview so it's missing a page here and there, but it should help you understand some of the principles. For a great read, buy the whole book.

What if I want to learn the math behind it?
Does it go past triple integrals? (I hate having to wait for years of college to understand things)
 

millirad

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It's worse than you thought Niko, it's quadruple integrals with trigonometry. :D Hope you get it going Wags.
 
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MISTERWILLING

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I can do custom machining for you at much better prices then you would get going to a machine shop. Custom fine lens threads can't really be done without purchasing a custom tap though. Please keep us posted on your finds as I am trying to collimate a multimode diode too. I have a red to-3 diode I'm trying to put into a laser show, supposedly it has a FAC so I might be able to get a beam out out of it pretty easily but I have to get the beam down to 3mm to get it to work in my scanner. And from what I understand a to-3 is simply a c-mount diode mounted on a tec and sealed up. I might end up selling it if I cant get the beam down to that size but the price was right so its worth a shot to get a 400mW 635nm at $200.
 

heruursciences

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It isn't very hard if you have two positive FL: lenses, one cylinder lens and one aspheric. correct the main beam with a short FL aspheric to a sharp line. Then correct the line with a cylinder lens...

OR use a negative FL lens to make the slow axis diverge the same as the nearly corrected fast axis, you aim to get the beam that stays square the longest time... then correct with a longish FL aspheric lens.

oR CORRECT AS #1 ABOVE and use an anamorphic prism pair to fold the beam into it's best collimated dot.
 

sbdwag

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Re: Lets Collimate a C-mount diode ok! Thanks Chris

It isn't very hard if you have two positive FL: lenses, one cylinder lens and one aspheric. correct the main beam with a short FL aspheric to a sharp line. Then correct the line with a cylinder lens...


Chris

Thanks for the comments Yes thats what Im doing with the 1W I purchased from you Im using a Meridith glass lens to create a thin line and then sending through a 100mmFL cylinder lens works great. Using a 9mm diode is easy because there is already a machined module to house it.

The problem for me is housing a C-mount and positioning an Aspheric lens at the right distance from the emitter and being able to adjust it. And fixing it in place

There are no such modules out there that I know of that will do that unless you have some tricks up your sleeves.:wave:

Chris also is you sales add post here still valid? Cause If it is I want to order a 5w C-mount 808nm from you along with a 1w 808nm c-mount to practice on. Please pm me about availability.

Regards
sbdwag
 
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ElektroFreak

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I didn't know you meant that you were looking for a way to mount the diode and build a module. C-mount diodes only require a flat heat-conductive surface and a hole tapped for a screw size that fits the hole on the diode. I've seen people mount the diode itself directly on a small block of aluminum (NO thermal compound), which is then attached to a TEC. The warm side of the TEC is then mounted on the flat part of a CPU heatsink. Various creative ways to hold the lenses exist from silly putty to expensive mounting hardware. If you get a system laid out well like this then it's a simple matter to take the measurements with a micrometer and design and machine (or have machined) a block with mounts for final assembly.
 
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