In analytical chemistry

Analytical chemistry

Analytical chemistry is the study of the separation, identification, and quantification of the chemical components of natural and artificial materials. Qualitative analysis gives an indication of the identity of the chemical species in the sample and quantitative analysis determines the amount of...

, dark current refers to the constant response produced by a spectrochemical receptor, even in the absence of radiation. This response adds to the signal produced when the receptor is used to measure light

Light

Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 and so must be dealt with to determine how much of the detector response is actually due to the radiation. To compensate for this extra signal, the dark current may be measured in the absence of radiation and then subtracted from the final signal or reduced to zero by a compensating circuit

Electronic circuit

An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow...

. Dealing with dark current is a form of blank correction

Blank (solution)

A blank solution is a solution containing little to no analyte of interest, usually used to calibrate instruments such as a colorimeter....

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