Abstract: A method of operating a liquid crystal light valve having a photoconductor and a liquid crystal involves selecting a photoconductor with an appropriate bandgap and an input light having a limited frequency range with a center frequency matching a bandgap of the photoconductor. This results in the light being more uniformly absorbed through the bulk of the photoconductor and the light blocking layer or the light blocking layer and the mirror can be eliminated. The photoconductor can be optimized for sensitivity and short carrier lifetimes necessary for high frame rates.

Abstract: A temperature indicator which in one preferred embodiment comprises a translucent or transparent confectionery head having a cavity therein. A flexible elongated resilient stem, preferably formed of a plastic material has one end thereof, which is provided with a plurality of small holes, inserted into the cavity. Each of the holes is at least partially filled with a temperature sensitive material capable of melting at a temperature typically within the range from 96.degree. to 110.degree. FWith each material mounted within a hole being adapted to melt at a different temperature within the aforesaid range. The material filling each hole within the stem is preferably of a color which contrasts with the material in the other holes for ease of identification. One or more of the materials in each hole will melt depending upon the temperature of the individual ingesting the lollipop.