Exicor technology has been used to solve several issues for our customers that manufacture laser crystal material.

The standard method for selecting suitable portions of an ingot to drill or "core" material for use as laser rods has long involved the use of a light source and large crossed polarizers. Highly skilled personnel were required to rotate the polarizers to illuminate the birefringence pattern. Once these patterns were found, the operator would mark the areas for best locations to core.

Exicor is now used to measure the birefringence of these crystals automatically and much more precisely. The operator merely places the sample on the system and defines the mapping area. The birefringence map is automatically created and a print-out of the map may be made and affixed to the top of the crystal. The machining personnel know exactly where to core the material.
In the sample measurement above, the red pixels indicate areas of high birefringence. The blue and grey/black areas are low birefringence and are considered "usable" material. The angle of the fast axis is also known and can be used to further define and select material with the appropriate characteristics. For example, an area may have high birefringence with a homogeneous fast axis.

How Exicor has assisted customers:

• Both magnitude and angle may be contributing factors to the performance of laser rods.
• Companies can now segment the market based upon birefringence quality and charge a premium for the cores exhibiting the lowest birefringence.
• Exicor has served these customers to decrease the analysis time and the level of personnel. An operator may now make these decisions instead of engineers and scientists.

For this application and samples 7 kg or less, we suggest use of the following systems:

Exicor 150AT, Exicor IR

For larger crystals, Exicor 450AT may be a suitable choice.