Abstract: Nonlinear optical borates LiB3O5,CsB3O5 and CsLiB6O10 contain B3O7 anionic groups as basic structural units.They have similar linear and nonlinear optical features,such as a short ultraviolet cutoff,a relatively large nonlinear optical coefficient and a high optical damage threshold,which make them suitable for frequency conversion in the ultraviolet region.This paper presents a description of the recent development of these crystals.

Key words: Nonlinear optical borates LiB3O5,CsB3O5 and CsLiB6O10 contain B3O7 anionic groups as basic structural units.They have similar linear and nonlinear optical features,such as a short ultraviolet cutoff,a relatively large nonlinear optical coefficient and a high optical damage threshold,which make them suitable for frequency conversion in the ultraviolet region.This paper presents a description of the recent development of these crystals.