Detectors - StellarNet, Inc.

What is the Spectrometer’s Baseline Offset?

Nov 10, 2017 | Detectors, Electronics, Glossary of Spectroscopy Terms

The baseline offset is the number of counts generated by the detector when there is no light. Several sources of noise are always present, so it is impossible to have no counts. The main components of baseline offset are electronic offset, dark current, and readout...

What is Temperature Compensation?

May 25, 2017 | Detectors, Glossary of Spectroscopy Terms

There are 15 “optically black” pixels on StellarNet detectors that are not hit by light during an acquisition. They provide a continuous measurement of the average dark spectrum and can be used to adjust for baseline drift during an experiment. In other words, this...

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 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...