Olympus U-CTB Thick Berek Compensator

The Olympus U-CTB is a thick Berek compensator for quantitative retardation measurement in polarized light microscopy. The Berek compensator uses a tilting calcite plate to introduce a variable, calibrated retardation into the optical path, allowing precise measurement of the optical path difference (OPD) of birefringent specimens. The thick design extends the measurable retardation range compared to standard Berek compensators, making it suitable for strongly birefringent materials such as minerals, polymers, and liquid crystals. It inserts into the optical path of Olympus BX and UIS2 series microscopes and is used in conjunction with crossed polarizers for quantitative birefringence analysis.