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Rainbow dot?

Elopement

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Is there a laser that will project the colours of the rainbow onto a single dot?
 

Crazlaser

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Do you mean like a white laser? Some people have done white builds with knife edges or pbs cubes. Please clarify.


Upgraded to underwear?
 

diachi

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Do you mean like a white laser? Some people have done white builds with knife edges or pbs cubes. Please clarify.


Upgraded to underwear?

Usually dichros, not knife edge. Knife edge is for combining multiple diodes of the same wavelength, it wouldn't work well with RGB as the beams wouldn't be superimposed.

You can use PBS too, but a PBS cube can only combine two beams and they need to have different polarizations (horizontal, vertical).
 
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You won't find a white laser pointer easily, but there are lasers designed for use in show systems that combine RGB to create white.
 

Crazlaser

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Usually dichros, not knife edge. Knife edge is for combining multiple diodes of the same wavelength, it wouldn't work well with RGB as the beams wouldn't be superimposed.

You can use PBS too, but a PBS cube can only combine two beams and they need to have different polarizations (horizontal, vertical).
That's not all true. I have seen wicked lasers combine three lasers all on the same plane with a pbs cube. Just my $0.02
 

diachi

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That's not all true. I have seen wicked lasers combine three lasers all on the same plane with a pbs cube. Just my $0.02

Actually, it is true. I know the image you're talking about, that's not a PBS cube. It's a dichro cube. Just because it's a cube doesn't mean it's a PBS, and a PBS doesn't need to be a cube either. It can be a plate.

As I said before, a PBS cube will take two beams (of opposite polarization) and combine them into one. You can also pass in a single randomly polarized beam in and get two oppositely polarized beams out.

Here's the image I think you're referring to:



And white light split into RGB with a similar cube:



They're used in video projectors. Three of the faces have an LCD on them. R, G and B light enters its respective LCD and then the cube, which combines the three colour channels to form a full colour image.

Argon white, but not a pointer.

Sorry to be pedantic, but Argon/Krypton - You need the Krypton for the red part. It also gives you that nice yellow line in the middle. Gives you some B/G lines too. :)

 
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Alaskan

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I've got a few of those cubes from projectors, mine are massive, nearly 3 inches on a side. I was considering using them with expanded beams of RGB to make white.
 
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diachi

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I've got a few of those cubes from projectors, mine are massive, nearly 3 inches on a side. I was considering using them with expanded beams of RGB to make white.

The one I had was big, but yours sound massive!

That sounds pretty cool though. Just a heads up, I've heard they can be a pain in the ass to get aligned.
 

Alaskan

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I don't know if I will ever use them in a device, just too massive, even for me. I tried to use a six inch diameter 160X beam expander on one of my 532nm DPSS pointers and quickly learned it's too darn heavy to use, only with a tripod but I did get a few beam shots with it before I gave up on it's weight. Today, with the possibility of being considered a laser attack, beam shots into the sky can be hazardous to ones welfare, so not doing that lately.
 

Crazlaser

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Actually, it is true. I know the image you're talking about, that's not a PBS cube. It's a dichro cube. Just because it's a cube doesn't mean it's a PBS, and a PBS doesn't need to be a cube either. It can be a plate.

As I said before, a PBS cube will take two beams (of opposite polarization) and combine them into one. You can also pass in a single randomly polarized beam in and get two oppositely polarized beams out.

Here's the image I think you're referring to:



And white light split into RGB with a similar cube:



They're used in video projectors. Three of the faces have an LCD on them. R, G and B light enters its respective LCD and then the cube, which combines the three colour channels to form a full colour image.
Yes that's what I was talking about. I stand corrected. Do you know anyone that sells a dichro cube? And are there any image comparisons of both?
 

Elopement

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I'm not looking for an external device to shine a laser on to, I am looking for an all-in-one pen which can emit an assortment of coloured laser in a rainbow like fashion into a single dot please.
 

diachi

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I'm not looking for an external device to shine a laser on to, I am looking for an all-in-one pen which can emit an assortment of coloured laser in a rainbow like fashion into a single dot please.
You're not going to get it in anything as small as a pen. You'll also be hard pressed to find anything commercial that meets your requirements, it'd need to be custom built.
 




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