Molecular Devices GenePix 4300A, User Manual

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Introduction
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Emission Filters
The GenePix 4300A/4400A Microarray Scanner is available in standard
configuration with either two or four lasers. The scanner can be custom
configured with one to four lasers. Each laser (red, yellow, green, and
blue) includes a matching emission filter pre-installed in the sixteen-
position filter cartridge.
Four positions in the filter cartridge are reserved for the standard
emission filters.
• Position 1 – red (661 to 690 nm)
• Position 5 – yellow (619–641 nm)
• Position 9 – green (562–596 nm)
• Position 13 – blue (513–555 nm)
These filters are not accessible, however, the remaining twelve
positions are available for custom filter installation.
Each standard emission filter is optimized for the emission spectrum of
the respective dye, designed to reject laser light at OD 8 (optical
density) for each respective laser excitation, and reject broad-spectrum
light at OD 5.
For specific information on custom filters and their applications, refer to
the filter manufacturer’s website.
• Semrock Inc.: www.semrock.com
• Chroma Technology Corp: www.chroma.com
PMT
The GenePix 4300A/4400A Microarray Scanner uses a high-sensitivity,
low-noise PMT to detect the emitted fluorescent light. A PMT converts
incident photons into electrons through the photoelectric effect. When
an incident photon impinges on the active surface of the PMT (the
photocathode), an electron is generated. The electron flows through a
series of electron multipliers (dynodes) to the anode. The amount of
current that flows from the anode is directly proportional to the number
of photons at the photocathode.
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