FOL technology addresses limitations observed in prior scanners in several ways:
High-accuracy position detectors, used in the X and Y axes, accurately locate each fluorescent pixel. Optic aberrations and galvanometer imperfections no longer dominate scan linearity; thus, consistently accurate scan linearity and excellent gridding performance are ensured.
The scan arm is physically small, enabling the objective, a low-mass, high-Numerical Aperture (NA) lens, to be located within a millimeter of the probe array. The large NA (0.62) objective provides a four-fold improvement in collection efficiency, which eliminates the need for multiple pass scans; only a single pass is required to deliver consistently high performance. Since line-scan speeds greater than fifty lines per second are easily achieved, Affymetrix largest format chips scan in just about half the time of that of the previous scanner.
The confocal optics structure results in an emission beam (a point instead of a line) detection path. This configuration allows emission detection to be implemented with a fixed-collection lens and pinhole that greatly facilitate simple and robust optical alignment. Taken as a whole, FOL technology consistently delivers outstandingly crisp, uniform, and geometrically accurate images.
A SOLID STATE GREEN LASER
Regardless of scanning technology, the laser is one of the most critical compone