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CCD Cameras

SNR

For any electronic measuring system, the signal-to-noise ratio (SNR) characterizes the quality of a measurement and determines the ultimate performance of the system.

With a CCD (charge-coupled device) image sensor, the SNR value specifically represents the ratio of the measured light signal to the combined noise, which consists of undesirable signal components arising in the electronic system, and inherent natural variation of the incident photon flux.

The three primary sources of noise in a CCD imaging system are photon noise, dark noise, and read noise, all of which must be considered in the SNR calculation.

A large signal-to-noise ratio is important in the acquisition of high-quality digital images, and is particularly critical inapplications requiring precise light measurements.

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