A ~532-nm green laser beam, passed through a pointer’s photonic-crystal cap to produce multiple diffracted beams, excites the pink dye in an hourglass toy, causing the dye to fluoresce in a golden-orange color along the path of the diffracted beams.
—Omar Khayyam and Syed Abuthahir Ziaudeen, Dr. Zakir Husain College, Ilayangudi, India
01 Sep 2019