Editorial | The Shape of Microscopy, Today
THE MICROSCOPE
2018, Volume 66:1, p. ii
DOI
https://doi.org/10.59082/RBCU8069
AUTHOR
Gary J. Laughlin
EXCERPT
Occasionally, I will catch a glimpse of microscopy in headline news that relates to fundamental topics that have been taught in virtually every introductory microscopy course at McCrone Research Institute since 1960. It often involves a new discovery related to one of the laws, theories, or rules that provide guidance when it comes to our understanding of physical optics or optical crystallography. I remember in 2000, after having taught the law of refraction (Snell’s Law) for many years and repeating its claims several hundred times, reading about “negative (refractive) index” materials. When light entering such a substance refracts, the propagation direction of the refracted ray is on the same side of the surface normal as the incident ray. “What?” you say. “That is not correct. Refractive index is always positive.” Turns out, it is possible, and certain materials can have a negative refractive index. Of course, they have to be artificially engineered and contain nanostructures, i.e., some kind of metallic, nanoscopic, electromagnetic resonators. But this is not usually the case in nature or the classroom.
