Measurement of fluorescence decay times
US6809816B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 24, 2003 |
| Grant date | Oct 26, 2004 |
| Priority date | — |
| Expiry date | May 15, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/6408
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Laser pulses from laser head 12 pass through objective lens 16 to a focal spot in sample spot 17. If a pulse hits a fluorophore molecule in the focal spot a fluorescence photon is emitted which is collected by lens 16, reflected by dichroic mirror 15 through filter 20, which blocks photons of other wavelengths, to single photon counting photomultiplier unit 21. On detecting a photon, photomultiplier unit 21 generates an output pulse which is coupled, with a short delay, by pulse controller 30 to driver circuit 24 which causes laser head 12 to generate another laser pulse. Thus the interval between the laser pulses is substantially equal to the time between excitation of, and fluorescence emission by, the fluorophore molecule. Computer 23 coupled to photomultiplier unit 21 and driver circuit 24 determines the decay time by measurement of a number of fluorescence events.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.