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Wide Spectral Widht Visible laser(20-30nm)

dustydude

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Hello my first post here!

I am looking for information on wide spectral width lasers.
For most purposes I think the closer to monochromatic the better with lasers but i'm looking to head the other direction. I understand the lasing process causes the monochromaticity.

Spectral Width of about 20-30nm in the visible?
Any ideas people?

Thanks,
DD
 
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HIMNL9

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Sorry, what exactly do you mean with "spectral width" of 20 or 40 nm ?

A single color that can be varied in a range of 20 or 40 nm ? ..... if so, i highly doubt that it can be acquired at hobby level (some variable-cavity units can do this, with specific lasing mediums, but as far as i remember, they are lab or industrial only, and have absurd costs)

Or, a mixed-wavelenghts beam ? ..... you can always mix different diodes, like, 635 and 660 or 670, but you can't mix more than two of them, using a PBS, and anyway you still obtain a beam made with 2 different wavelenghts mixed together, NOT a beam that go from one to the other .....

Or also, a multiline gas unit ? ..... there are already multiline Ar.Ion and Ar-Kr lasers, emitting in this way, but also in this case, is a mix of different single-line wavelenghts .....

Otherwise i'm misunderstanding, sorry.
 

dustydude

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Say for a laser thats stated at 532nm. If you stick it into a very high resolution spectrometer you still that there'll be a distribution of wavelenghts around 532nm. In most cases its very narrow like 0.005nm or something along those lines.

Its for a research project. So i thought drawing on the weath of knowledge from hobbiests would be a great start.

Thanks,
 

magonegro

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Wavelength of laser emision from a diode is a little sensitive to heat, maybe you could take a chance hypercooling it... No 40nm variations but maybe +-10nm
 

Prototype

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Unless he still wants monochromatic output with variable wavelengths, then he could just get an optical parametric oscillator, they can cover the entire visible spectrum, though they're usually pulsed, being pumped by an Nd:YAG set up I believe.
 
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That's the thing, I don't think he's asking for variable monochromatic output, he's asking for a wide spectral output, like an LED. I think he's asking for an output with a FWHM of 20-30 nm, not a monochromatic output that can be adjusted by 20 to 30 nm.

If it's really just monochromatic output that's widely-adjustable, there are even easier ways to do it, depending on what kinds of intensities are needed. A lightbulb and a monochromator will give you light just as monochromatic as your set-up allows and covers the entire spectrum too, but of course you're going to have lots of other issues to consider, like light intensity and such.

ETA: I've also used some reflective optical filters that were spec'd as having a transmission centered at a specific wavelength, with a FWHM of 20nm, giving a very simple solution.
 
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dustydude

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The goal is a wide spectral range (20-30nm) but with LED's the intensity is too low.

Also getting a large focus depth with an LED would further reduce the intensity.
 

HIMNL9

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I suppose it can depend from what led you use .....

It's not a laser, ok, but, as example, the green one, emits 3500 lumens (at 30A :eek:), with a declared spectral bandwidth of 39nm, from a 3x4mm chip ..... with a dome condenser followed from a focusing doublet, must be possible to focus it in a decent 15 to 20 mm spot, without too much difficults ..... and reaching to focus it decently, must give some good result, you don't think ?

;)
 

oic0

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I suppose it can depend from what led you use .....

It's not a laser, ok, but, as example, the green one, emits 3500 lumens (at 30A :eek:), with a declared spectral bandwidth of 39nm, from a 3x4mm chip ..... with a dome condenser followed from a focusing doublet, must be possible to focus it in a decent 15 to 20 mm spot, without too much difficults ..... and reaching to focus it decently, must give some good result, you don't think ?

;)
WTB that in a compact flashlight body with one of those A123 super high discharge batteries. What can I say, I like obscene novelties.
 




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