Beta barium borate (BBO or _ß-BaB2O4) is an excellent nonlinear crystal. It has a large phase matching range, high nonlinearity (6 times larger than KDP), a high optical damage threshold and good mechanical and thermal stability. This trigonal uniaxial crystal has a wide transparency range from 190nm to 2500nm.

Such a crystal is used to generate higher harmonics (SHG, THG, 4HG, 5HG) of the Nd:YAG laser as well as SHG and THG of the Ti:Sapphire and Alexandrite lasers, for tunable optical parametric oscillators (OPO) – pumped at 355nm, 532nm or 1064nm, for UV sources – generated by SHG, SFG (sum frequency generation) of dye lasers, and for autocorrelation (a method for optical measurement of pulse durations) of ultrashort pulses (ps and fs). BBO is also used as an electro-optical Q-switch, for example at 266nm. In such applications, it can be supplied up to a length of 20mm and can also be supplied with Cr/Au-coated electrodes.

Automated technologies (TSSG method) allow the production of high quality crystals with 45mm-50mm diameter and 20mm length. The following sizes of optical elements are available: (3mm-12mm) x (3mm-12mm) x (5mm-20mm); 0.1mm-1.0mm thin plates are also available.