PerkinElmer Wallac 1420, Руководство пользователя

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Note
Each flash contributes to the total excitation energy. Flashes keep on occurring until the
required total excitation energy is achieved. However, because the energy comes in discrete
flashes the last flash will cause the total excitation energy to exceed the required amount by
a maximum of not more than the energy in one flash. This will not be significant if there are
many flashes but could be significant if there are only a few flashes. E.g. in standard
measurements the amount of flashes is about 1000, the variation in the total excitation
energy is thus 1/1000 or 0.1 %. If the amount of flashes is about 100, the variation in
excitation energies is 1/100 or 1 %.
Light Integration Reference Level
These values change the excitation energy approximately linearly. Changing this value from
50 to 100 has about the same effect as changing the capacitor from 1 to 2. The number of
flashes can be seen from the result viewer by selecting
View all result data .
Emission filters
You can select the emission filter from the drop-down list of available filters. See the
chapter on Filters for more information about how to define filters.
Factory pre-set emission filter names begin with a letter indicating the technology for which
they are to be used: D is for time-resolved fluorometry. After the letter comes the
wavelength.
Emission aperture
In front of the photomultiplier tube there is a 4-position aperture slide, which has three
different apertures and a shutter position.
The normal aperture is circular with a diameter of about 4 mm and it is used for factory set
labels.
The small aperture is circular but only 1 mm in diameter. This allows you to shift the
dynamic range of the emission signal for a particular user selected label which may
otherwise exceed the linear range of the instrument. This aperture is used for the top
fluorometry factory-set labels.
There is also a large circular aperture 5 mm in diameter.
The shutter is used at all times when no measurement is occurring to prevent stray light
getting to the photomultiplier tube.