Fluorescence, phosphorescence, and photoluminescence occur when a sample is excited by absorbing photons and then these photons are emitted with a characteristic decay time. Fluorescence is when the absorbing and emitting species is an atom or molecule. Phosphorescence is similar to fluorescence but with a longer time gap between absorption and emission. Photoluminescence is the term physicists use to describe the absorption and emission of light by materials such as semiconductor and nanotubes.
A chemical species absorbs a photon and is excited to a singlet electronic state. It then relaxes via non-radiative mechanisms and emits a lower-energy photon. This allows it to transition to the ground electronic state. A spectrograph and camera can be used to obtain the spectrum of emission, with the intensity correlating to the concentration of the chemical species.
Recommended Products for Fluorescence Decay
Spectrometers
IsoPlane
Multi-Award Winning Imaging Spectrometer
- Patented astigmatism free Schmidt-Czerny-Turner design
- High spectral resolution
- Superior signal-to-noise ratio
SpectraPro HRS
High Performance Imaging Spectrographs
- 60% improvement in spectral resolution and SNR
- Astigmatism-corrected optical system
- Interchangeable grating turrets
ProEM
Ultralow Light Detection Camera
- Deep cooling
- ≥95% quantum efficiency
- eXcelon 3 technology
BLAZE
Award Winning Cameras for Spectroscopy
- Up to 300% higher NIR sensitivity
- True -100°C cooling
- Permanent vacuum guarantee
PyLoN
Extremely Low Noise Liquid Nitrogen Cooled Cameras
- -120 °C cryogenic cooling
- 1800 spectra per second
- Ultra low noise