Popis: |
Thin metallized viscoelastic layers coated by a mirror electrode and addressed by an active matrix are proposed for ue in schlieren-optical light-valve projection systems for high-definition television (HDTV). Previously, the deformation behavior of such viscoelastic spatial light modulators (VSLMs) was analyzed extensively by use of the theories of electrostatics, linear viscoelasticity, and plate bending. In the meantime, most of the theoretical results could be qualitatively confirmed by interferometric deformation measurement. Of the many predictions derived from the theoretical treatment, only the deformation patterns to be expected with one bright line and with two bright lines separated by a dark line are demonstrated here. Furthermore, the number of grating periods per picture element as well as the ratio of electrode width and grating period are discussed in view of resolution limits. In addition, three concepts of full-color schlierenoptical projection systems for the above reflective VSLMS are described and compared. All three systems contain a light source, three spatial light modulators (one for each primary color), and a projection lens. The first concept is based on a very small light source and a correspondingly small stop; in the second concept, mirror bars as in the well-known Eidophor projector are employed; and parallel light is assumed in the third concept. |