McCutcheon M J, Miller R G
J Histochem Cytochem. 1979 Jan;27(1):246-9. doi: 10.1177/27.1.374582.
The factor which can limit fluorescence intensity resolution in a flow cytometer of the type in which cells pass perpendicularly through a focussed laser beam depends on signal intensity. For the brightest sources (e.g. fluorescent DNA stains), the coefficient of variation (CV) is limited in our system to around 3% by stream hydrodynamics, unstable illumination intensity, nonstoichiometric staining, etc. The weakest detectable sources (e.g. fluorescent cell-surface labels) are limited in coefficient of variation by shot noise in the photomultiplier due to constant background light levels. Finally, over a fairly wide brightness range between these extremes, resolution is determined primarily by photoelectron statistical variation on the signal itself (i.e. "photon statistics"). Thus photon collection and detection efficiency (solid angle, barrier filter passband, detector quantum efficiency) become of primary importance.
在细胞垂直穿过聚焦激光束的流式细胞仪中，限制荧光强度分辨率的因素取决于信号强度。对于最亮的信号源（如荧光DNA染料），在我们的系统中，由于流体力、不稳定的照明强度、非化学计量染色等因素，变异系数（CV）被限制在约3%。最弱的可检测信号源（如荧光细胞表面标记），由于恒定背景光水平导致的光电倍增管散粒噪声，其变异系数受到限制。最后，在这两个极端之间相当宽的亮度范围内，分辨率主要由信号本身的光电子统计变化（即“光子统计”）决定。因此，光子收集和检测效率（立体角、阻挡滤光片通带、探测器量子效率）变得至关重要。
