A line of optical filters designed to efficiently combine or separate multiple laser beams has been launched by Semrock Inc. The LaserMux dichroic beamsplitters/combiners can multiplex 16 popular laser lines and can be used in reverse to demultiplex. Six filters for the nominal 405-, 440-, 488-, 514-, 561- and 635-nm wavelengths have been introduced. They are used at 45° incidence while maintaining a high degree of polarization insensitivity. The flatness ensures that there is less than one Rayleigh range of focal shift across a 2.5-mm beam diameter.