A wavelength shifter is a photofluorescent material that absorbs higher frequency

Frequency

Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...

 photon

Photon

In physics, a photon is an elementary particle, the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force...

s and emits lower frequency photons. In most cases, the material absorbs one photon, and emits multiple lower-energy photons.

These materials can be used to increase the efficiency of a photovoltaic cell (solar cell) by changing one "too-high" energy photon into multiple "just-right" energy photons. Optical fiber

Optical fiber

An optical fiber is a flexible, transparent fiber made of a pure glass not much wider than a human hair. It functions as a waveguide, or "light pipe", to transmit light between the two ends of the fiber. The field of applied science and engineering concerned with the design and application of...

s doped with a wavelength shifter are typically used to collect scintillation light in particle physics experiments

Particle physics experiments

Particle physics experiments briefly discusses a number of past, present, and proposed experiments with particle accelerators, throughout the world. In addition, some important accelerator interactions are discussed...

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