Base Microscope The base microscope for "The A1" is an inverted Nikon Eclipse Ti-E equipped for standard widefield fluorescence, brightfield, and differential interference contrast (DIC) microscopy (all used mainly to locate objects of interest).
Spectral Imaging A unique feature of the system is the ability to collect spectral information from a sample. Using a specialized multichannel PMT detector, 32 images can be collected simultaneously in about half a second. Each image covers a discrete spectral band with a width of 2.5, 5, or 10 nm. Spectral imaging can be used to computationally unmix the signals of fluorophores with similar emission spectra. For example, for most imaging modalities, separating GFP from YFP is difficult, but can be done relatively easily using a spectral detector. Even probes with closely spaced emission spectra, such as GFP and Alexa Fluor 488, can potentially be separated. Autofluorescence from endogenous fluorophores in cells and tissues can also be separated and subsequently removed from images. In addition to the separation of overlapping fluorescence emissions, the spectral detector can also be used to generate emission spectra from an unknown fluorophore present in samples.
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