BD FACSCanto II, Справочное руководство

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Appendix A: Technical Overview 119
Once compensation has been set for one sample, the spectral overlap setting
(compensation value) remains valid whether a dim or bright sample is run.
Figure A-14 illustrates this principle. Although the signals differ in intensity, the
percentage of signal detected in the FITC and PE channels remains constant.
Figure A-14 Two FITC signals of different intensity
Electronics System
Any discussion of digital electronics requires a basic understanding of the bit.
Computers and digital circuits use bits (binary numbers consisting of ones and
zeros) to pass information. A 4-bit number has 4 binary digits that are either 1 or
0. A 10-bit number has 10 binary digits that are either 1 or 0. An 18-bit number
has 18 binary digits that are either 1 or 0.
100100101011101010 is an example of an 18-bit number. Converted into base
10, the scale we normally use, this number is 150,250. There are 262,144 18-bit
values.
FITC PE
different intensity FITC signals
same proportion or percentage of
spillover in PE channel
nor
m
al
ized int
ens
it
y