Thorlabs has released its DMLP Series of Dichroic Filters and Beamsplitters, which are ideal for filtering spectral components in fluorescence applications and for splitting or combining optical beams in laser applications that require minimal wavefront distortion.
The series offers high and flat transmission and reflection bands, steep cutoff edges, and minimal stray light, which in turn leads to improved signal-to-noise ratios and faster measurements. They are designed for use with light that is incident at a 45° angle.
These filters are fabricated from a hard-coated ion-beam-sputtered thin coating that is placed on a simple ultra-low auto-fluorescence fused-silica substrate without using any adhesives. The dielectric glass coatings are as hard as the glass substrate itself with a scratch-dig of 40-20. Additionally, they are virtually impervious to humidity-induced shifting. The uniformity and high flatness of the coated glass avoids unwanted wavefront distortions. The filters can be cleaned and handled like standard glass optics. They withstand high optical irradiation intensities with no noticeable degradation or burn out, even with prolonged use and exposure to ultraviolet light.