Related Experiment Video
Updated: Jul 2, 2026
Low-cost Custom Fabrication and Mode-locked Operation of an All-normal-dispersion Femtosecond Fiber Laser for Multiphoton Microscopy
Published on: November 22, 2019
Subnanosecond single photon counting fluorescence spectroscopy using synchronously pumped tunable dye laser
1Biophysics Graduate Program and Department of Physiology, University of Texas Health Science Center, Dallas, Texas 75235.
Abstract:
A synchronously pumped tunable dye laser has been constructed and interfaced with a modified Ortec 9200 photon counting system for the purpose of measuring subnanosecond relaxation phenomena. The dye laser excitation pulse, which has an intrinsic 35-ps FWHM for Rhodamine 6G, is 350 ps when measured by time-correlated single photon counting. This value appears to be characteristic of the transit time jitter in the RCA 8850 photomultiplier tube. Subnanosecond fluorescence lifetimes of Rhodamine B with KI as a quencher have been determined by deconvolution of photons counted versus elapsed time using the method of moments; the shortest lifetime measured was 68 ps. Various technical aspects of the system are discussed with emphasis on applications to biophysical problems.
