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Back to the OSAC Lexicon

extinction

condition when an anisotropic substance ap- pears dark when observed between crossed polarizers and occurs when the vibration directions of the specimen are parallel to the vibration directions of the polarizer and analyzer.

Committee
Interdisciplinary
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org
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