Tydex, a private Russian company, produces optical components and instruments for research and industry: spectroscopy, metrology, pyrometry and thermography, THz electronics, lasers. We supply lenses, doublets, windows, prisms, mirrors, diffraction gratings, holographic notch filters, IR-polarizers, Golay cells, high-resistivity silicon optics, Ge-, Si- and ZnSe-optics,  nonlinear and laser crystals and waveplates. For our products we use such materials as germanium, silicon, zinc selenide, crystal quartz, synthetic sapphire, synthetic diamond, fused silica, BK-7 glass, LiF, MgF2, CaF2, BaF2, NaCl, KCl, KBr, CsI, various alloys. Antireflection, reflection, partial reflection coatings from 200 nm to 14 mkm are available.