Photonics Dictionary: A

Ablation applied to polymers and chemical solids. Process of material removal that minimizes edge damage but will not heat the surrounding portion of the sample.

That point in the electromagnetic spectrum at which an optical system focuses the most chemically effective rays.

Electromagnetic energy that is capable of producing photochemical activity.

The creation of a chemical reaction in a substance when radiation is directed to it.

The study of chemical changes produced by radiation.

A device that measures the intensity of photochemically active radiation, particularly from the sun. One form of this instrument determines the fluorescence initiated by the radiation.

Actinometry refers to the measurement of the intensity of radiation, particularly ultraviolet (UV) radiation or sunlight. It is commonly used in atmospheric science, environmental monitoring, and...

The transport of molecules in a cell which requires the use of a cell's internal energy. The energy used in the cell may be ATP as a primary transport or an electrochemical gradient give as the...

A chemical placed in a solution that will indicate when an excess of a substance or ion has been reached by coloring the precipitate after the chemical itself has been totally adsorbed.

An aptamer is a short, single-stranded DNA or RNA molecule that can bind to a specific target molecule with high affinity and specificity. Aptamers are often referred to as chemical antibodies due to...

An atomic absorption spectrometer (AAS) is an analytical instrument used to determine the concentration of specific chemical elements in a sample by measuring the absorption of light at...

The analysis of fluorescence emitted by discrete atoms, in flames, that have absorbed radiation from an external source. It is used to study the physical and chemical processes that arise from...

An atomic force microscope (AFM) is a high-resolution imaging and measurement instrument used in nanotechnology, materials science, and biology. It is a type of scanning probe microscope that...

Attenuated total reflectance (ATR) spectroscopy is a technique used in analytical chemistry to obtain IR spectra of samples. It is particularly useful for analyzing solid and liquid samples without...

Attosecond-pump attosecond-probe spectroscopy (APAP) is an advanced technique in ultrafast spectroscopy that allows scientists to study the dynamics of electronic processes occurring on extremely...

Any photographic medium that, when chemically developed, produces an exact photographic reproduction of the original.

A vapor-phase oxidation process for fabricating graded-index optical fibers. It differs from outside vapor phase deposition in that the preform is developed radially rather than longitudinally. An...