PerkinElmer EnVision, Instrument Manual

Page: 54 / 111

Informations about user instructions and warnings
44
Laser beam path
The path of the laser beam from the laser to the sample well is described in
the following picture:
Picture 6. Path of the laser beam.
The laser has been placed on top of the instrument under a protective casing
as shown in Picture 1, and the optical fiber connected to the laser is led via
the electronics compartment to the light-tight instrument compartment. In
the instrument compartment, the light produced by the laser is directed to
the sample with the help of a mirror and lenses. Therefore, when the optical
fiber is connected, it is impossible that the user would be exposed to laser
beam unintentionally.
Detaching the optical fiber
The optical fiber of the laser is connected to the laser with a SMA-905
connector. The other end of the optical fiber is locked by tightening the
locking screw at the side as shown in Picture 6. The casing protecting the
laser and optical fiber as well as the cover plate of the electronics
compartment are fastened with screws. Therefore, it is impossible to reach
the laser or its fiber connectors without tools.
Additional safety features of the instrument
To ensure laser safety, the device contains two special features. These are
the automatic closing of the beam shutter and the measuring of laser pulse
light before the next laser pulse.
The laser is equipped with a built-in beam shutter, which remains closed
except when measuring. When the measuring is started, the beam shutter
opens and, after measuring, it closes automatically. Thus, no laser beam is
emitted except during measuring, even if the laser is turned on by mistake.
The other safety feature, i.e. measuring of laser pulse light, is intended for
the measuring phase. As mentioned above, laser beam is led by an optical
fiber to the light-tight instrument compartment. Before entering a sample,
part of the laser pulse light is led into a photodiode for a reference
Protective casing of the laser
Laser
Light-tight
instrument
compart-
ment
Optical fiber inside
protective tube
Screw fastening