Introduction
When you’re in need of a fl ashlight, there’s nothing worse than an equipment failure. Whether you’re a plumber crawling around a basement, a spelunker exploring a cave, or a policeman searching for a crime suspect in the middle of the night, being left in the dark may slow your work, get you lost, or even mean the difference between life and death. Yet conventional fl ashlights are notoriously unreliable due to the inherent ineffi ciency and short lifetime of the incandescent light bulb.
