This long-pass set is designed to take advantage of the superior resolution, sensitivity, and image fidelity of today’s state-of-the-art laser-based microscopes. The filter spectra are optimized to capture the maximum fluorescence from DAPI and other similar fluorophores while offering superb blocking of popular 405 nm or 375 nm solid-state laser diodes. The dichroic offers excellent flatness for minimal focus shift and aberrations of the laser beam spot at the sample. Our improved version is certified to deliver dichroic flatness