PULSMODULASJON AV EKSITASJONSLYSKILDEN I VAESKESTROEMCYTOFOTOMETERE.

摘要

A method for increasing the intensity of the excitation light, and thereby the sensitivity, of flow cytometers. The initial part of the signal produced by each cell as it enters the excitation focus (2) triggers a current pulse to the excitation light source (1), with a duration approximately similar to the time required for the cell to pass through said focus (2). This current pulse, which is superimposed on the constant operating current to said light source (1), causes an increase of the intensity of the excitation light during the period when the cell is passing through said excitation focus (2) and thereby an increase of the sensitivity of the flow cytometer. Cell size is measured by light scattering using a detector 12, and cellular content of DNA is measured by spectral fluorescence using detectors 15. IMAGE