Absorbance
Definition
The base-10 logarithm of incident divided by transmitted radiant power under the specified measurement conditions. Wavelength, path length, specimen preparation and reference measurements matter. A recorded absorbance is not automatically a concentration.
- Context
- Optical measurement
For example, equal absorbance readings from two extracts need compatible wavelengths and preparation before a meaningful concentration comparison can be considered.
That interpretation requires a suitable calibration and assessment of departures from the measurement model.
Related terms
- Quantum Yield
- Quantum yield is a ratio of a specified event to the number of photons absorbed under stated conditions. In fluorescence it commonly...
- Raman Shift
- Raman shift is a difference in wavenumber associated with energy exchanged between incident radiation and a material during Raman scattering. Its interpretation...
- Stokes Shift
- Stokes shift describes displacement between corresponding absorption and emission spectral positions, often compared through their maxima. The convention, units, material and measurement...