Re: Uses of Bulk Nano Materials (was beanstalks)

From: Keith F. Lynch (kfl_at_KeithLynch.net)
Date: 06/17/04 

Date: 16 Jun 2004 23:13:39 -0400

Henry Spencer <henry@spsystems.net> wrote:
> In that context, you do need a wavelength that will penetrate
> atmosphere.

> Note that it's perfectly possible to build eye-safe lasers that will
> do so. At wavelengths longer than (if memory serves) about 1400nm,
> the eyeball is essentially opaque, so you no longer get that nasty
> focused spot on the retina. There's no problem in principle with
> picking a wavelength that fits in one of the atmospheric transmission
> "windows" beyond there. Unfortunately, (a) there's somewhat of a
> shortage of good lasers at such wavelengths, and (b) I'm not sure
> there are any good solar cells that far down either.

Why not take the opposite approach: Ultraviolet rather than infrared? 

-- 
Keith F. Lynch - http://keithlynch.net/
Please see http://keithlynch.net/email.html before emailing me.

Relevant Pages

  • Re: Uses of Bulk Nano Materials (was beanstalks)
    ... >> atmosphere. ... >> the eyeball is essentially opaque, so you no longer get that nasty ... >> picking a wavelength that fits in one of the atmospheric transmission ... i think you would have similar laser problem, ...
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  • Re: Uses of Bulk Nano Materials (was beanstalks)
    ... >> atmosphere. ... >> the eyeball is essentially opaque, so you no longer get that nasty ... >> picking a wavelength that fits in one of the atmospheric transmission ... i think you would have similar laser problem, ...
    (sci.astro)
  • Re: Uses of Bulk Nano Materials (was beanstalks)
    ... >> atmosphere. ... >> the eyeball is essentially opaque, so you no longer get that nasty ... >> picking a wavelength that fits in one of the atmospheric transmission ... i think you would have similar laser problem, ...
    (sci.space.policy)
  • Re: Uses of Bulk Nano Materials (was beanstalks)
    ... > atmosphere. ... > the eyeball is essentially opaque, so you no longer get that nasty ... > picking a wavelength that fits in one of the atmospheric transmission ...
    (sci.materials)
  • Re: Uses of Bulk Nano Materials (was beanstalks)
    ... > atmosphere. ... > the eyeball is essentially opaque, so you no longer get that nasty ... > picking a wavelength that fits in one of the atmospheric transmission ...
    (sci.space.policy)