TY - JOUR
T1 - Phase-modulation fluorometry using a frequency-doubled pulsed laser diode light source
AU - Berndt, Klaus W.
AU - Gryczynski, Ignacy
AU - Lakowicz, Joseph R.
PY - 1990
Y1 - 1990
N2 - We describe the use of a pulsed frequency-doubled laser diode, the Hamamatsu model PLP-01 picosecond light pulser, as a 413-nm excitation light source for frequency-domain fluorescence measurements. The modulated incident light, over a range of modulation frequencies, is provided by the harmonic content of the pulse train. In comparison with the more usual light source for harmonic-content excitation, a sync-pumped/cavity dumped/frequency doubled dye laser, the 413-nm PLP-01 has a longer pulse width (FWHM of 40 ps), a similar pulse repetition rate (up to 10 MHz), much less output power at a fixed wavelength (0.44-mW peak, 220-nW maximum average power), but is less expensive, small-sized, and easy to handle. Using the PLP-01, we were able to perform frequency-domain fluorescence measurements up to an upper modulation frequency of about 2000 MHz, and to resolve mixtures of fluorophores exhibiting different lifetimes. During our tests, we observed remarkable and lasting (2 h) time drifts between the optical output and the electrical trigger input or output. At present, work is in progress at Hamamatsu to eliminate these drifts.
AB - We describe the use of a pulsed frequency-doubled laser diode, the Hamamatsu model PLP-01 picosecond light pulser, as a 413-nm excitation light source for frequency-domain fluorescence measurements. The modulated incident light, over a range of modulation frequencies, is provided by the harmonic content of the pulse train. In comparison with the more usual light source for harmonic-content excitation, a sync-pumped/cavity dumped/frequency doubled dye laser, the 413-nm PLP-01 has a longer pulse width (FWHM of 40 ps), a similar pulse repetition rate (up to 10 MHz), much less output power at a fixed wavelength (0.44-mW peak, 220-nW maximum average power), but is less expensive, small-sized, and easy to handle. Using the PLP-01, we were able to perform frequency-domain fluorescence measurements up to an upper modulation frequency of about 2000 MHz, and to resolve mixtures of fluorophores exhibiting different lifetimes. During our tests, we observed remarkable and lasting (2 h) time drifts between the optical output and the electrical trigger input or output. At present, work is in progress at Hamamatsu to eliminate these drifts.
UR - http://www.scopus.com/inward/record.url?scp=0001106012&partnerID=8YFLogxK
U2 - 10.1063/1.1141099
DO - 10.1063/1.1141099
M3 - Article
AN - SCOPUS:0001106012
SN - 0034-6748
VL - 61
SP - 1816
EP - 1820
JO - Review of Scientific Instruments
JF - Review of Scientific Instruments
IS - 7
ER -