Absorbance & Transmittance
Absorbance (A) and Transmittance (T) are measurements used in molecular spectroscopy. Molecular spectroscopy measures the fraction of light that a transparent and finite-length sample absorbs or transmits over a given wavelength range. This technique is useful for determining the identity and concentration of an unknown absorbing specie within a sample.
How Molecular Absorption Occurs?
Using Absorbance for Quantitative Analysis
How Transmittance is Related to Absorption?
How to Represent the Absorption Properties of Sample?
Typical setups for Absorbance & Transmittance
In a brief description, the setups supplied by Sarspec for a typical absorbance and transmittance measurement consists in transporting the light produced by a deuterium and/or tungsten-halogen light source (LS-DW, LS-DWHP, or LS-W) through an optical fiber to a sample holder, which might be a cuvette holder, flow cell, or transmittance probe. A second optical fiber transports the light from the sample holder to the spectrometer, which detects and records the intensity of transmitted light in real-time. Schematic and real-life examples of setups available from Sarspec can be found in the following sections.