EP1686202A1 - SINGLE CRYSTAL OF HIGHLY PURIFIED HEXAGONAL BORON NITRIDE CAPABLE OF FAR ULTRAVIOLET HIGH-LUMINANCE LIGHT EMISSION, PROCESS FOR PRODUCING THE SAME, FAR ULTRAVIOLET HIGH-LUMINANCE LIGHT EMITTING DEVICE INCLUDING THE SINGLE CRYSTAL, AND UTILIZING THE DEVICE, SOLID LASER AND SOLID LIGHT EMITTING UNIT | Patent Bear