The 10B20BS.3 Broadband Dielectric Beamsplitter is made of N-BK7 glass, 25.4 mm in diameter, 6.1 mm thick, with a surface flatness of λ/10, and coated for 1290-1580 nm. Our broadband dielectric beamsplitters are designed to provide general purpose laser beam splitting and combining for visible through near infrared applications. Each coating is essentially achromatic across a wide spectral band so that a single optic will work for the entire range of a particular tunable laser, for several laser diode wavelengths, or for most visible laser wavelengths.