| interfr-package {interfr} | R Documentation |
Interference colors for polarized light microscopy
Description
Based on a 2013 paper by Sorensen, this package automates computation and plotting of interference colors produced when a transparent material is observed between crossed polarizer and analyzer. Two kinds of plots may be produced: the classical Michel-Levy chart (parralel color boundaries and oblique iso-birefringence lines in a rectangular plot with thickness and retardation axes) and the more recent Raith-Sorensen chart (hyperbolic color boundaries in a thickness-birefringence rectangular plot). Functions for automatic extraction of birefringence profiles from images, and their spatial or statistical interpretation are still under development.
Details
Using the interfr package, users can compute and display their own interference chart, customizing sample thickness and birefringence ranges. This may be of special interest when dealing with thick samples (that exceed the 20-40 micrometers range of classical thin plates). It makes use of the colorSpec package for physically realistic representation of colors. A function is provided to illustrate the color shifts given by the use of quarter and lambda plates.
References
Sorensen, B.E. (2013) A revised Michel-Levy interference colour chart based on first-principles calculations. Eur. J. Mineral., 2013, 25, 5-10. DOI:10.1127/0935-1221/2013/0025-2252