Specifications

PN 718113AF
4
Laser Induced Fluorescence Detection
System Overview — LIF System
WARNING
During normal operation of the LIF Detector, laser light is not accessible to the
user. To prevent potentially harmful laser light from being emitted from the end
of the fiber cable, an interlock mechanism turns off the laser if the laser fiber cable
is disconnected from the interconnect module, or if the cartridge cover is opened.
Always power off the laser module and instrument before removing any of the LIF
system module(s).
If these precautions should be defeated and the beam becomes accessible,
DO NOT look into the beam or direct it toward someone else.
488 nm Argon Ion Laser Module
The Beckman Coulter 488 nm laser is an air-cooled Argon Ion Laser. Two indicator lights are located
on the front of the 488 nm Laser Module. Refer to Figure 1 for more information. The green light
flashes to indicate that the interlock circuit is complete and the laser is preparing to light (in
approximately 40 seconds). Once the laser is operating, the green light will stay on continuously
until the laser is turned off, the cartridge cover opened, or until the fiber cable coupler is
disconnected from the LIF Interconnect Module.
The yellow light is a current limit indicator. A sensor in the laser module measures the amount of
laser light being produced. Circuits in the laser module adjust the amount of current being drawn
to maintain a stable 3mW output. When the laser tube is new, a fairly low current easily produces
3mW; as the laser tube ages, increasingly more current is needed to maintain the 3mW output.
The yellow indicator light will come on when the system begins to draw more than 7A of current.
This light indicates that the laser tube should be replaced; when it comes on, contact
Beckman Coulter Customer Service for assistance. Laser tube life should be longer than 2,000 hours.