Re: All helicopters should be grounded

Cynic wrote:
On 01 Jul 2008 13:42:00 GMT, fburton@xxxxxxx (Francis Burton) wrote:

I find it extremely difficult to believe that any light source powered
by a few mW would give sufficient general illumination to hamper the

Although you probably know, it is worth pointing out that the
power required to produce light and the power in the light itself
are quite different measures. So for example LEDs can produce much
more light power for the same power input compared to incandescent
bulbs.

Of course I am aware of that. But the light power can never exceed
the input power. And if 5mW can produce such an intense general
illumination that it can cause a dazzle, it would make it many orders
of magnitude more efficient than any other light source, so why can we
not get torches (flashlights) that use a diffused laser beam?


I suspect that the situation is that it isn't/wasn't /general illumination/, but is/was a sequence of reflections of a still-focused beam.

I can get such an effect with my laser pointer and a cut glass bowl. Waving the pointer at the bowl produces a series dazzlingly bright flashes as the light is reflected from individual facets, right into my eyes.

It may be that a laser pointer would produce a similar series of intense reflections as the beam hit "shiny" bits within the cab.

Just a theory...

--
Sue


.

Relevant Pages

  • Re: All helicopters should be grounded
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    (uk.legal)
  • Re: All helicopters should be grounded
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  • Re: Efficiency and maximum power transfer
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