An electron beam addressed liquid crystal light valve projector
The contents of this dissertation relate to a liquid crystal light valve which is addressed by an electron beam. The light valve has been configured with a computer aided designed optical projection system, to produce an electron beam addressed liquid crystal light valve projector. The projector is capable of turning an electrical signal into a corresponding projected picture. A minimum resolution of 33um was demonstrated in a smectic-A liquid crystal light valve and one of 40um in a dyed phase change guest-host liquid crystal light valve. The diameter of the active area of the light valve was 45mm. Crucial to the realization of the projector was the patented invention and design of an electrically highly anisotropic disc of 47mm diameter which was approximately 2mm thick. The disc, which was conducting through its thickness and insulating across its plane, formed the top interface of the liquid crystal light valve and permitted the electron beam to deposit a charge pattern which could be conveyed to the thin liquid crystal layer without loss of resolution. The disc was made using a specially constructed piece of apparatus wherein the holes in a glass capillary array were filled with a low melting point alloy. Discs were made using three different low melting point alloys and their various merits were considered. Consideration was also given to developing the deflection coils used in this projector. Computer aided design resulted in a deflection coil system capable of a resolution of over 8 x 108 pixels in a 50mm x 50mm frame at a half angular aperture of 1mrad. In order to evaluate the resolution of the light valve, a micro-computer controlled dot pattern generator was built. This was used to drive the deflection coils in such a way as to control both the dwell time and position of the electron beam spot. Lines of different spacings were written on the light valve. Electron and optical micrographs are presented to demonstrate the quality of the anisotropic disc. Photographs and optical micrographs are included to show the pictures which were obtained from the projector and also the lines written on the light valve.