Patent ID: 7166851

Claim:
A self-contained device for measuring exposure to radiation comprising: a semiconductor substrate; a light source for producing a light output, wherein the light source is mounted on the semiconductor substrate; a splitting device for separating the light output into at least two split portions; a polymer dispersed liquid crystal component residing on the semiconductor substrate, the polymer dispersed liquid crystal component illuminated by at least one of the split light output portions; a device in contact with semiconductor substrate for generating an electrical field within the polymer dispersed liquid crystal component; a first detector to detect the intensity of the light output portion that passes through the polymer dispersed liquid crystal component; a second detector to detect the intensity of at least one light component that did not illuminate the polymer dispersed liquid crystal component; a logic device for comparing the intensities detected by the first and second detectors, and determining if a warning signal should be generated; and a device for generating a warning signal if the logic device determines a warning signal should be generated.