MCS260B
CORNERSTONE 260B MONOCHROMATORS
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4 SHUTTER
An electronic shutter is integrated into the Cornerstone 260B
monochromator’s design. It is mounted
inside the housing at the input port. This shutter is normally closed.
The shutter is used to close the light path when light is not required. This allows the light source to
remain on, and therefore remain warmed up, so that it continues to provide stable performance.
Additionally, restarting a lamp results in wear of the filament (with quartz tungsten halogen lamps) or wear
of the anode/cathode (with arc lamps). When the light is not needed during short periods, closing the
shutter is suggested.
Diffraction gratings are mounted on a rotating turret inside the monochromator. When the
monochromator switches between diffraction gratings, the changing angle of the grating causes light to
be diffracted at various wavelengths. This includes white light, which is output at a higher power than
other individual wavelengths. In order to prevent saturation of a detection system, it is good practice to
close the shutter temporarily while changing gratings. It is especially important to prevent saturation and
possible damage when using a photomultiplier tube.
A scan may be completed while the shutter is closed to perform background subtraction calculations on
subsequent scans completed while the shutter is open.
Note that the shutter is not designed to block high power direct light. When using a 450W or greater light
source, heat mitigation strategies should be employed. For example, Oriel offers liquid filters to protect
the shutter, filters and other items to prevent potential heat damage.
4.1 REMOTE SHUTTER OPERATION
The BNC female connector located on the outside of the monochromator allows the shutter to be
controlled remotely, if desired (Fig. 7)
. A ‘low’ condition (0 volts) will open the shutter. The shutter
may also be opened by completing a connection between the BNC conductor and shield (i.e.
shorting the connector). Control can be overridden by the shutter commands issued from a
computer or the optional hand controller. Leave the BNC connector open to use the hand
controller or computer exclusively.
Figure 7: Remote Shutter Control BNC Connector.
