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A method for growing solid state laser crystal boules is disclosed that when made into laser rods do not need separate end caps attached to the laser rods. The crystal boule is grown as a single integral unit with three segments. Two segments, the end segments, are un-doped or non-laser active, and they flank a central segment of the boule that is doped with an active laser ion. A first end segment of the crystal boule is first grown from un-doped melt material in a first crucible by slowly withdrawing its growing end from the first melt. The boule is then transferred to a doped melt in a second crucible where its growing end is submersed therein to grow the doped, laser active central segment. The temperature of the melt in the second crucible is initially higher than the growing temperature of the first melt and causes the growing end of the boule to melt. The temperature of the second melt is then lowered and the central segment of the crystal boule is grown onto the first end segment in an integral manner by slowly withdrawing the crystal boule from the melt. After the central segment of the boule has been grown, the boule is removed from the second crucible and is transferred to the un-doped melt in the first crucible where its growing end is submersed therein to grow the doped second end segment. The temperature of the un-doped melt in the first crucible is initially higher than the growing temperature of the second melt and causes the growing end of the crystal boule to melt. The temperature of the un-doped first melt is then lowered and the second end segment of the crystal boule is grown in an integral manner by slowly withdrawing the crystal boule from the un-doped first melt. |
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