Nonlinear optical (NLO) crystals are commonly used in laser technology for the conversion of light from one frequency to another. Among known NLO crystals, borates of the type LiB3O5 (LBO) and BaB2O4 (BBO) have found wide commercial success because of their capabilities for generating high-power laser light. These and other NLO compounds are, however, limited in their application to the generation of UV and VUV light as they are damaged by exposure to high power lasers, exhibit excessive absorption and light scattering of incident or absorbed light, may be hydroscopic, and are too costly and time consuming for commercial production.
The NLO crystal described in the U.S. Patent number 7,534,377 that issued May 19th, 2009, was invented by Drs. Doug Keszler, Ning Ye, Michael Hruschka and Jennifer Stone-Sundberg. The patent claims La0.7Y0.3Sc3(BO3)4 (LYSB) with a plus or minus range of 0.1 in the relative stoichiometric ratio of La and Y, crystallized in the R32 space group and is unique among all LnSc3(BO3)4 compounds in that it forms as a mixture of two lanthanide atoms, La and Y, at a fixed compositional ratios. It also has optical properties intermediate to those of BBO and LBO, better thermo-optic properties (based on structure) and better absorption and less light scattering characteristics in comparison to those of BBO. Moreover, in contrast to BBO and LBO, LYSB is not hygroscopic and is also easier to grow than BBO or LBO.
LYSB's combination of characteristics in terms of optical and physical properties, as well as stability and manufacturability make it an attractive and commercially competitive alternative to other crystals on the market.
Please click on the following link to the issued patent on the USPTO website: http://tinyurl.com/lto9gv