BOULDER, Colo., Feb. 17, 2011 — A new series of cube beamsplitters from REO are intended for demanding dense wavelength division multiplexing applications in telecommunications. Optimized for use in Gires-Tournois interferometer-based interleavers and dispersion compensators, the nonpolarizing beamsplitters deliver broadband, polarization-insensitive operation and good path length matching for the reflected and transmitted beams. This consistently delivers the transmission and channel isolation characteristics required by demanding long-haul and metro network applications. Traditional nonpolarizing beamsplitters are limited by either a narrow operating band or high internal absorption, according to the company, who says that it avoids these drawbacks by employing all dielectric, ion-beam-sputtered coatings, together with a high-index-of-refraction contrast material set. The result are telecom C-band (1525 to 1570 nm) and L-band (1565 to 1620 nm) beamsplitters that deliver a transmission and reflection ratio of 50% ±1.5% over their entire operating range, with the s and p polarization components matched to within 2%. A series of high-precision, proprietary fabrication techniques, together with the company’s Activated Covalent Bonding adhesive-free bonding process, enable it to consistently produce cubes with an optical path difference between the two output beams of <3 µm, together with sub arc-minute beam deviation accuracy and low wavefront distortion (surface flatness λ/20 at 633 nm). The beamsplitters are available in the 3- to 12.5-mm-size range and are fabricated from fused silica substrates.