Re: 1um pixels, anyone?

Alfred Molon wrote:

In article <44144266.60205@xxxxxxxxx>, username@xxxxxxxxx says...


Somebody should explain why the noise level is the square root of the signal.

http://en.wikipedia.org/wiki/Poisson_distribution
The square root comes from the math of the Poisson
distribution.


Ok. Where on that page is written that the noise is the square root of the signal? I did a text search for "root" and found nothing.

In the box on the right side of the page, click on the link to variance.
Variance is the "mean squared deviation" so the noise in the Poisson
distribution is the square root of the variance.

Roger
.

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