LITHIUM TRIBORATE SINGLE CRYSTAL AND ITS PRODUCTION

• Main Authors: NUMATA TOSHIO, SUTEIIBUN EE MAAKUGURAFU, SATO MASAZUMI
• Format: Patent
• Language: English
• Published: 11.04.1995
• Edition: 6
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; CHEMISTRY; CRYSTAL GROWTH; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; FREQUENCY-CHANGING; METALLURGY; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

PURPOSE:To obtain a lithium triborate single crystal having stable and high output by using the axis as the principal axis of the seed crystal and the easy growth plane as the principal plane, thereby improving the laser damage strength. CONSTITUTION:A powdery mixture of Li2CO3, B2O3, etc., is put into a platinum crucible and heated at about 900 deg.C to obtain a solution having a temperature distribution of 0.1-5 deg.C)/cm. A seed crystal having axis as the principal axis is brought into contact with the solution using the easy growth plane as the principal plane and a crystal is grown by a hot solution top seeding method. The rotation of the seed crystal is accelerated clockwise to 30rpm in about 10sec, maintained for 80sec, decelerated and stopped in 10see, stopped for 10sec and rotated counterclockwise for a prescribed period. The reciprocating rotation is repeated to effect the stirring of the solution and the growth of the seed crystal. The grown crystal is cooled at a prescribed cooling rate to obtain a lithium triborate single crystal having a laser damage strength (J/cm ) of about 51-525.