FIG. 7.

Blast-induced color changes in photonic crystalline microstructures. Blast injury dosimeter (BID) arrays were affixed to rats prior to blast exposure at peak overpressure of 120 or 140 kPa. Clear blast-induced colorimetric changes were observed in individual photonic crystals on (A) flexible aclar substrates or (B) rigid silicone substrates. (C) Other microstructures on the same arrays required more powerful blast exposure to induce ultrastructural alterations, and did not exhibit color change. Thus, BID arrays comprised of photonic microstructures with varying blast exposure thresholds may serve as accurate dosimeters to measure individual blast exposure levels.