Abstract: Transmission and reflection type holograms may be formed utilizing a novel polymer-dispersed liquid crystal (PDLC) material and its unique switching characteristics to form optical elements. Applications for these switchable holograms include communications switches and switchable transmission, and reflection red, green, and blue lenses. The PDLC material offers all of the features of holographic photopolymers with the added advantage that the hologram can be switched on and off with the application of an electric field. The material is a mixture of a polymerizable monomer and liquid crystal, along with other ingredients, including a photoinitiator dye. Upon irradiation, the liquid crystal separates as a distinct phase of nanometer-size droplets aligned in periodic channels forming the hologram. The material is called a holographic polymer-dispersed liquid crystal (H-PDLC).

Abstract: Transmission and reflection type holograms may be formed utilizing a novel polymer-dispersed liquid crystal (PDLC) material and its unique switching characteristics to form optical elements. Applications for these switchable holograms include communications switches and switchable transmission, and reflection red, green, and blue lenses. The PDLC material offers all of the features of holographic photopolymers with the added advantage that the hologram can be switched on and off with the application of an electric field. The material is a mixture of a polymerizable monomer and liquid crystal, along with other ingredients, including a photoinitiator dye. Upon irradiation, the liquid crystal separates as a distinct phase of nanometer-size droplets aligned in periodic channels forming the hologram. The material is called a holographic polymer-dispersed liquid crystal (H-PDLC).

Abstract: A radioisotope production facility (12) produces radioisotopes having application to Positron Emission Tomography. The radioisotopes produced include .sup.18 F, .sup.13 N, .sup.15 O, and .sup.11 C, and are produced by irradiating a selected target material (40) with a high energy .sup.3 He.sup.++ beam accelerated in a radio frequency quadruple (RFQ) linear accelerator (34). The facility includes, in addition to the RFQ linear accelerator and the selected target, a source of .sup.3 He.sup.++ ions (30), low energy transport means (32) for focusing the .sup.3 He.sup.++ beam into the RFQ linear accelerator, and a high energy transport means (36) for directing the accelerated .sup.3 He.sup.++ beam at the selected target. Further included is a target subsystem (16) that holds the target, automatically prepares precursors containing the .sup.18 F, .sup.13 N, .sup.15 O, and .sup.