What is Electronic Noise?

May 25, 2017 | Detectors, Glossary of Spectroscopy Terms

Electronic noise is all the noise generated by the electronic circuits after the electrons are converted to a voltage. This includes noise from any amplifiers and the A/D converter. For example, conversions of exactly the same charge will not necessarily yield exactly...

What is Spectrometer Shot Noise?

May 25, 2017 | Detectors, Glossary of Spectroscopy Terms

Shot noise is a type of electronic noise that happens because electrons and photons are discrete particles. It arises in situations where the measurement involves counting events. In spectroscopy experiments, the event is a photon generating an electron. This process...

What is Signal to Noise Ratio?

May 25, 2017 | Glossary of Spectroscopy Terms, Spectroscopy

The signal to noise ratio, often abbreviated S/N, is exactly what it sounds like; it’s the ratio of the magnitude of the signal to the magnitude of the noise. Experiments need a large S/N to be able to distinguish features in the signal from the noise. If the S/N is...

What is a Spectrometer’s Dark Noise?

May 25, 2017 | Detectors, Glossary of Spectroscopy Terms

Dark noise is the noise associated with the dark current. It is a type of shot noise where the event is a thermally generated electron. If the dark current generates N counts on the detector, the dark noise is √N. Dark noise is indirectly dependent on temperature...

What is Spectrometer Noise?

May 25, 2017 | Detectors, Glossary of Spectroscopy Terms

Noise is a collective term for sources of unwanted signal. Some noise sources introduce systematic error, and can be corrected for, such as with a dark spectrum. Other noise sources introduce random error, and can be averaged out over several acquisitions. The...