Electrically controlled light filters

Hybrid Scriar and Electrically Controlled Light Filters... 

Fig. 35 shows a suitable setup with a liquid crystal display for producing electrically controllable colors With a transmissive mode display, inclined incident collimated white light is diffracted into the spectral colors when a display element is excited. A filter in front of the display only permits transmission of perpendicular incident light. 

Light Exposures. Silk fabric samples, 0.25 m x 0.17 m, were mounted in Atlas Electric Devices aluminum sample holders according to AATCC Test Method 16E-1982 (7). An Atlas Ci-35 Weather-Ometer xenon-arc was used on continuous light cycle. Exposures were conducted at an irradiance of 0.35 W/m2 measured at 340 nm and the irradiance was monitored and controlled automatically. Borosilicate inner and outer filters were used to simulate the solar spectrum. The relative humidity was maintained at 65% and the black panel temperature was 50°C. The actual fabric temperature during the irradiation was measured, using small thermocouples threaded into the fabric, and was found to be 35 C. Control samples for these tests were kept in the dark at 35°C and 65% RH for the same time period as the illuminated samples. 

Polystyrene capacitors have exceptionally low tan S values (< 10 q, making them well suited for frequency-selective circuits in telecommunications equipment. Polymer capacitors are widely used for power-factor correction in fluorescent lighting units, and in start/run circuitry for medium-type electric motors used in washing machines, tumble-dryers and copying machines for example. They are also used in filter circuits to suppress radio frequencies transmitted along main leads. Such interference noise may originate from mechanical switches, furnace controllers and switch mode power supplies it not only spoils radio and television reception but can also cause serious faults in data-processing and computer equipment. 

PERSONAL PROTECTION wear full protective clothing and chemical-resistant gloves wear chemical safety goggles wear self-contained breathing apparatus a closed system of local exhaust ventilation is recommended to control emissions at the source and to prevent dispersion into general work area use dust explosion-proof electrical equipment and lighting for extra personal protection, use a P2 filter respirator for harmful particles maintain eyewash baths and safety showers in work area. 

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