This third part in a series on non-linearity looks at other tests and how they can be applied in laboratories that must meet FDA regulations.


Photonic crystal fibers are novel optical waveguides that offer promising alternatives for various sensing applications. This article describes an experiment in which the absorption spectrum of acetylene was measured to demonstrate the effectiveness of photonic bandgap fibers for high sensitivity gas detection. Methane also was studied to determine the same capability in weakly absorbing gases.

The authors describe their work characterizing archaelogical ceramics by means of Fourier-transform infrared (FT-IR) absorption. Semiquantitative analyses using the technique can identify the main components and trace elements constituting the ceramics. An accurate knowledge of the chemical composition of the samples gives useful information for their classification.


The author presents a discussion of the operation and optical complexities of the human eye.


MEMS are small, microfabricated devices that are finding application in a variety of industries in both analytical and manufacturing settings. This paper reviews the properties of diffractive MEMS devices and examines their application in chemical spectroscopy.

Researchers have recently used computed tomography imaging scans to help separate fact from fiction in the ancient pharaoh's death.