Noise reduction techniques for CCD image sensors

The properties of several widely used CCD signal-processing schemes are discussed in detail. A common feature is that correlated double sampling techniques are used to attenuate low frequency noise. The relative merits of each scheme depend on the exact nature of the noise sources. Formulae are derived which enable assessment of the best scheme to use for a particular device once its noise spectrum is known; conversely, the relationship between output noise and such parameters as signal integration time can be used to determine the noise spectrum. The analysis also applies to charge injection devices and voltage sampling diode arrays. For each scheme the formulae are used to predict the readout noise for a system employing a cooled GEC MA328 CCD.