Fluorescence lifetime determination
AssigneeThe University Court of the University of Glasgow
InventorsAshley LYONS, Daniele FACCIO, Vytautas ZICKUS, Raul MENDOZA
Life of this patent
Estimating the term…
Abstract
An apparatus and method determine a fluorescence lifetime of a sample with a Mach-Zehnder interferometer. A beam splitter interferes a fluorescence signal traveling in a first arm with a frequency-matched reference pulse in a second arm, yielding two combined outputs. A first single-photon detector converts the first output into a signal proportional to its photon count, and a second detector produces an analogous signal for the second output. By correlating the detectors' signals while systematically varying the relative optical path delay between the interferometer arms, the system extracts the fluorescence lifetime of the sample.
Claims24
An apparatus for determining a fluorescence lifetime of a sample, the apparatus comprising:
- an interferometer, the interferometer comprising:
- a first arm for conveying a fluorescence signal from the sample;
- a second arm for conveying a reference pulse, wherein the reference pulse has a frequency selected to interfere with the fluorescence signal;
- a delay mechanism configured to control a relative path delay between the first and second arms;
- and
- a beam splitter having a first input connected to the first arm, a second input connected to the second arm, a first output configured to emit a first combined signal, and a second output configured to emit a second combined signal;
- a first photon detector connected to the first output so as to receive the first combined signal and output a first detection signal indicative of a number of photons in the first combined signal;
- a second photon detector connected to the second output so as to receive the second combined signal and output a second detection signal indicative of the number of photons in the second combined signal;
- and
- a lifetime determination unit connected to the first and second photon detectors, wherein the lifetime determination unit is configured to determine the fluorescence lifetime of the sample based on a correlation between the first and second detection signals over a range of relative path delays between the first and second arms.
6-7. (canceled)
(canceled)
A method of determining a fluorescence lifetime of a sample, the method comprising:
- receiving, at a beam splitter along a first arm of an interferometer, a fluorescence signal from the sample;
- receiving, at the beam splitter along a second arm of the interferometer, a reference pulse, wherein the reference pulse has a frequency selected to interfere with the fluorescence signal;
- interfering, by the beam splitter, the fluorescence signal with the reference pulse, wherein the beam splitter outputs a first combined signal from a first output and a second combined signal from a second output
- outputting, by a first photon detector that receives the first combined signal, a first detection signal indicative of a number of photons in the first combined signal;
- outputting, by a second photon detector that receives the second combined signal, a second detection signal indicative of the number of photons in the second combined signal;
- and
- determining the fluorescence lifetime of the sample based on a correlation between the first and second detection signals over a range of relative path delays between the first and second arms of the interferometer.
(canceled)
(canceled)
Dependencies are inferred from the claim text.