Imaging System Hardware
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performance is monitored in real time during acquisition, and corrected. The
utmost attention has been given to selecting and implementing components to
create a highly reliable, high-performance instrument.
Electronic
While the optical components of the GenePix scanner are indispensable for
generating the electrical current from the PMT, the electronic components are just
as important. They govern the operation of the PMT and the conversion of their
analog current signals into a digital signal that can be processed by the host
computer.
Axon Instruments is the world leader in the design and construction of low-noise
amplifiers. Our amplifiers are used around the world by researchers in the
neuroscience community. We have 20 years of expertise creating low-noise
amplifiers and high-performance computer hardware to digitize these signals. Our
expertise in this area has been applied to the GenePix scanner. Integrated with the
GenePix scanner is not only our high-performance analog-digital converter, but also
the experience and knowledge to create low-noise, high-performance amplifiers.
We have employed a unique design to ensure that the PMTs in GenePix scanner are
linear over a wide dynamic range, and that the signal-to-noise level exceeds all
other currently available microarray scanners.
General Items of Interest
Spatial Resolution
The GenePix Autoloader 4200AL is a scanning instrument. This means that a
single point of light is rapidly scanned across the microarray, and a composite
image is created from the digitized signals from the PMT. The spatial resolution of
the system refers to the size of this single scanning point. In the GenePix scanner,
the spatial resolution is 5
µ
m for a
Data Scan
, and 40
µ
m for a
Preview Scan
.
During the Preview Scan, the same 5-
µ
m spot is scanned; however the slow
Chapter 4