Hi,
I wonder how to calculate the Signal-to-Noise Ratio with the datasheet of a CMOS sensor?
I calculate the total excited photons (Signal_N) from the irradiance, conversion gain and quantum efficiency.
But, I am confused with the noise estimation.
The datasheet gives,
Parameter Specification Remarks FPN
=A0 =A0Remarks
=A0 =A0 =A0 =A0Unity gain.
45=3D62dB
On May 7, 8:32=A0am, Phil Hobbs
Some manufactureers will actually supply a map of the "noise" pixel by pixel. However, as this is a function of illumination (different gains in different pixels as you pointed out) it is difficult to use. In addition schott (quantum) noise can become significant.
It's a fairly involved calculation / experiment to determine the CMOS (or CCD) true performance. I'm still in the learning stage myself.
I wonder how our friends at Schott would feel about having their name applied to shot noise. ;-)
Return address scrambled. Replace nkbob with bobkn.
Top posting - a way of life.
(snip)
In addition schott (quantum) noise can become significant.
(snip)
Slip of the brain!
However, trying to get information out of Schott regarding the future supply of optical glasses is not possible. In a few short years (for me) they have gone from the supplier of choice to the supplier that I avoid like the plague.
Fixed pattern noise is multiplicative, so it's a more or less fixed fraction of the signal. FPN of 1% on a 1000-electron signal is 10 electrons, but with 60,000 electrons it's 600.
Cheers,
Phil Hobbs
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