Fibers of the synthetic polymer poly benzimidazole appear to resemble neon lights when illuminated with a combination of Hoffman modulated contrast and plane-polarized light with a first-order compensator in the light path.

Compare this photomicrograph to that of a darkfield version in the Olympus Microscopy Resource Center Darkfield Gallery to observe the enhanced three-dimensional appearance of fibers illuminated with Hoffman modulation contrast.

Poly Benzimidazole had the trademarked name CelazoleŽ PBI and is a high performance imidized thermoplastic. CelazoleŽ PBI is currently the highest performing engineering thermoplastic available in the marketplace. The polymer offers high heat resistance, good mechanical property retention, excellent wear resistance, and superior thermal insulation. Typical applications include vacuum tips, wafer carriers, contact seals, insulator bushings, thermal isolators, and guide rollers.