Techniques for Fabricating High Resolution Liquid Crystal Reticles

摘要

The overall objective of this two-phase program was to develop techniques for fabricating high resolution liquid crystal reticles suitable for military application. The first phase of this program consisted of three technology development tasks, namely substrate improvements, liquid crystal seals, and electronics seals. The goal of each development task was successfully accomplished. Results are summarized below: (1) Techniques were developed to produce 98 percent working electrode lines without repair (100 percent with repair) on LCR plates with a density of 580 lines per inch. Results were verified by optical inspection and electrical test. (2) LC cells fabricated with Ablefilm 539 sealant have now surpassed 7000 hours at +80 C and -17 C without cell deterioration. Additional cells with bulk electrodes and continuous AC voltage have surpassed 6200 hours at +25 C without alignment change. Other cells fabricated with Ablefilm 539 showed no signs of weakening when exposed to liquid nitrogen or boiling water conditions. (3) A dual coating of silicon nitride and parylene demonstrated moisture protection, but the process was costly to apply and difficult to repair. Conventional hybrid solder sealing technology was used to devise two alternate packaging concepts to maximize producibility and maintainability with potentially lower production costs. The second phase of this program consisted of designing, fabricating (using the technology and procedures developed under the Phase I program), testing and delivering a liquid crystal reticle.