Hex DIY Red Laser - The ULTIMATE burner idea! :-)

[stevetexas]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

I tried a similar idea with 4 diodes and had them rigged in parallel. My suggestion would be to give each diode its own circuit so you don't lose any diodes as I did (I lost 2 on this project)

The problem is aligning the modules. A CNC cone with holes for each module should do the trick (sort of like a christmas tree with each module pointed toward the same spot) Alignment is a MAJOR problem here....

 

[danielbriggs]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

Can someone please explain the whole cone lens thing?

How does having several lasers pointing to the top of the cone make them turn through 90 degs?

For the alligment part, how about having a ring with 6 posts. So you have a like a cake. Base plate + posts around the edge, top layer. Then using a FP thread, say M3, thread the posts. At the back of each aixis module, tap the same thread into the casing. Then you could just screw the moudles into the posts, and have a fine adjustment for each individual module.

Does anyone acutally sell these cone lens'?
We'll get there eventually!


Dan

 

[rog8811]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

I have tried this out in 2 dimensions, if you like, by sticking mirrors to a cube....

On the basis that a picture paints a thousand words I will post some.

First one is a schematic of a red green combiner I wanted to try.

 

[rog8811]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

Next is a view of the same thing in metal.........

 

[rog8811]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

And last, I stuck all the bits down with masking tape, held down one laser switch with a hammer held the other down by hand, held the camera in the other to take the picture....What I am saying is that this was not the ideal way to get this picture so the output is not perfect but it shows that it is feasable .

Regards rog8811

 

[SenKat]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

NICE work ! I am continually impressed by the ingenuity of the forum members - you guys ALL ROCK !

 

[rog8811]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

I am continually impressed by the ingenuity of the forum members - you guys ALL ROCK !

Why thankyou kind sir

Throwing ideas around like this is by far the best way I have found of moving forward!

Regards rog8811

 

[danielbriggs]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

Would a fresnel work?
http://science.howstuffworks.com/question244.htm

I'm trying to think of the most compact design of the lens system. Does the fresnel lens give suitable quality, or is it not ideal for laser application?

I think the best setup that I have thought of so far (excluding rog's idea - but I can't find a conical mirror lens for sale) is to have the modules pre colimated shining into a Plano-Convex Lens, then, just after the focal point of all beams, place another Plano-Convex Lens.

A smaller design would be to have the modules pre colimated shining into a Plano-Convex Lens, then, BEFORE the focal point of all beams, place a Plano-CONCAVE Lens.


Will this work?
And does anyone know a good supplier of lens' like some on NOVA lasers site,  but available in the UK?

Thanks,


Dan

 

[philguy]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

Well, a fresnel would work, but might not be the instrument of your choice. Fresnels are used for larger lens diameters. If you can find a normal lens, I'd use that, but a fresnel should do. Note though that a fresnel projects "rings", so it is of some lower quality than a normal one.

 

[Archane]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

A fresnel lens would work but dear god the math involved and the size we are talking about would really suck *Not it!*

We would have to know someone that does machine lens work and has alot of free time.

 

[rog8811]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

I think that freznels are just a cheap way of producing a large lens, I have never come across any as small as would be ideal for this application.
Stick with your first thoughts on the lens, I think that is the better route.

Regards rog8811

 

[danielbriggs]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

Ok, cheers guys. I was just reasearching and throwing a few ideas around.

So it looks like the only 2 viable ones so far are rog's conical mirror, and the multi concave/convex setup.

I'll have to get some to experiment!
Again: Does anyone know of any UK suppliers of good lens for my needs?
I can't really afford the huge shipping costs from NOVA (international) at the mo. (the shipping would cost more than the lens'!)

Dan

 

[rog8811]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

I am racking my brains for the name of a company I used years ago...they sold all sorts od ex military optics and the like...... If I remember I will post

Regards rog8811

 

[philguy]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

Well, how about an optician/optometrist/whatever-the-name-of-the-guy-who-makes-your-glasses?

It would cost about 20$ for one lens, but it will be the fl of your choice, a nice diameter and proper quality with a (relatively) low absorbance. Maybe he even cuts it for you.
If you are lucky, you might get them for 10each, if you just happen to need ones he has some he doesn't need...

Alternatively, try rigging up other optics...Slide projectors, OHPs, cameras/camcorders, magnifying glasses, glasses, whatever you can find to make it work.

But remember - for the two-lens-array, you need a focal length in the range of an inch, or around 2-3cm.


The deal with the polished cone is that you will have trouble getting it to work. To get the beams as close together as possible, they need to hit the cone as high as possible. And at some point, wehn they're at the very top, curvature and angle of the cone will disturb your wet dreams about the death star, as a) part of the laser will shoot past the cone (picture a circle on a triangle), and of the rest that gets reflected, most will be thrown off somewhere else (like the projection onto a cylinder/sphere).

You might have better luck if you try it with a pyramid instead of a cone, but it won't be an easy result.

I have to admit though that reflective optics always "pwn" refractive optics, and adjustment as well as adding lasers would be simple with that one.

 

[danielbriggs]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

Yeah - Could ask at my local shop.

But I wanted some cheap bits and bobs to mess around with, then when I know exactly what I need, I can order some in with exact specs.

I'll ask my physics dept. where they buy their lens' from, and I'll see if I can borrow some!
But a quick search turned up these:

http://cgi.ebay.co.uk/Lens-Glass-Do...ryZ26237QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

http://cgi.ebay.co.uk/Lens-Glass-Do...ryZ26237QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

http://cgi.ebay.co.uk/Lens-Glass-Do...ryZ26237QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

Or their whole range: http://stores.ebay.co.uk/Science-Lab-Supplies_Lenses_W0QQcolZ4QQdirZ1QQfsubZ4580637QQftidZ2QQtZkm

I think the 5cm focal length one seems quite good - as it's 38mm in diameter, so would be an idea candidate for a maglite 3/4/5/6 D cell!
+ It's cheap to order a few for trial & error

I might order some of these if you guys think they will do the trick.
Obviously, I will have to wait for the next lot of GB diodes to arrive, as I only have 1 at the mo. But 3 are on their way!

Cheers for all the help!


Dan

 

[philguy]

Re: Hex DIY Red Laser - The ULTIMATE burner idea!

yeah, trying to borrow them might be the best idea for experimenting with several FLs.

Keep in mind the diameter needed - it must be large enough, but the smaller the better, as to fit it into the Maglite housing.

Can't wait for the GB diodes to arrive...then I can build the "TriStar" (tm), and burn happily ever after
Although there, TEC might be a point to consider.