248.6 nm Ultrasteep Long Pass Filter

The MP-LPF-244 is an ultrasteep long pass filter designed specifically for the 244 nm laser line, primarily used in UV Raman spectroscopy, fluorescence detection, laser spectrum analysis, and other precision ultraviolet optical systems. This filter offers high blocking performance with OD > 6 at 244 nm, and provides an average transmittance greater than 90% over the 247.6–550.4 nm band. With a transition width of only 3 nm, it features an extremely steep spectral edge, effectively suppressing the laser line and Rayleigh scattering while improving the collection of Raman signals close to the laser wavelength. The filter is fabricated on a fused silica substrate and mounted in a 25 mm diameter circular metal ring, making it suitable for research-grade Raman spectrometers, fluorescence spectrometers, and custom optical systems.