The CSU-X1 is the advanced model of our CSU-series, which are widely recognized as the most powerful tools for live cell imaging. A Nipkow spinning disk containing about 20,000 pinholes and a second spinning disk containing the same number of microlens to focus excitation laser light into each corresponding pinhole are mechanically fixed with a motor, and very rapidly raster scan the field of view with about 1,000 laser beams when rotated. The pinhole and microlens pattern are arranged in our proprietary design to optimize raster scan. Multi-beam scanning with the CSU-X1 not only increases scanning speed, but also results in significantly lower photobleaching and phototoxicity, because multiple excitation needs only a low level of laser power at the specimen to fully excite fluorescence.