Types of Specimen that Can be Examined

Interference microscopy can be applied to the study of lignin distribution in wood, in differentiating xylem, and in chips during pulping. The only constraints are that the material can be embedded and sectioned, matched samples are available for calibration, and the specimen can be oriented to obtain transverse sections. 

The most common difficulties arise from the second constraint. For example, a pulp sample containing wood from different sources cannot be examined by interference microscopy because the value of Na will vary from fiber to fiber, making accurate calibration impossible. 

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