Abstract: Coherent light sources in the deep and vacuum UV (DUV and VUV) spectral regions become more important with the development of photolithography, laser micro-machining as well as laser spectroscopy. The review will briefly introduce how to use the anionic group theory to develop new borate-based DUV and VUV nonlinear optical crystals. Meanwhile, The basic linear and nonlinear optical properties of these borate-based crystals are systemically reviewed. Moreover, some typical examples to produce DUV and VUV harmonic generation and their applications are given.

Key words: Coherent light sources in the deep and vacuum UV (DUV and VUV) spectral regions become more important with the development of photolithography, laser micro-machining as well as laser spectroscopy. The review will briefly introduce how to use the anionic group theory to develop new borate-based DUV and VUV nonlinear optical crystals. Meanwhile, The basic linear and nonlinear optical properties of these borate-based crystals are systemically reviewed. Moreover, some typical examples to produce DUV and VUV harmonic generation and their applications are given.