BD FACSCanto II, Reference Manual, Page: 21 / 158

Chapter 1: Introduction 21
Collection Optics
From the flow cell, laser light is routed to the collection optics, which efficiently
gather the signals emitted and scattered from each particle. The 4-2 configuration
collection optics include two detector arrays, which consist of photomultiplier
tubes (PMTs) arranged in one octagon and one trigon as shown in Figure 1-4.
The octagon contains five PMTs and detects light from the 488-nm (blue) laser.
One PMT in the octagon collects side scatter (SSC) signals.
The trigon contains two PMTs and detects light from the 633-nm (red) laser.
Figure 1-4 Octagon and trigon detector arrays (4-2 configuration)
longpass
dichroic
mirror
bandpass
filter
red-laser
signal
trigon
octagon
blue-laser
signal
PMT