BD FACSCanto II, Reference Manual, Page: 120 / 158

120 BD FACSCanto II Flow Cytometer Reference Manual
Pulses
Inside the PMTs, the laser light is converted into an electrical signal. This
electrical signal is called a pulse.
Figure A-15 Anatomy of a pulse
A pulse begins when a particle enters the laser beam. At this point, both
the beam intensity and signal intensity are low.
The pulse reaches a maximum intensity or height when the particle
reaches the middle of the beam, where the beam and signal intensity are
the brightest. The peak intensity, or height of the pulse, is measured at
this point.
As the particle leaves the beam, the pulse trails off.
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