The role of the supervisor. Although a dissertation is an opportunity for you to work independently, you will usually be allocated a member of academic staff as a supervisor. Supervisors are there to help you shape your ideas and give you advice on how to conduct the research for your dissertation.
The TN device consists of the twisted nematic liquid crystal confined between two glass substrates with homogeneous planar orientation: the orientation of the director n on one substrate is rotated by 90 o with respect to n on another substrate.
A twisted prism is a nonconvex prism polyhedron constructed by a uniform q-prism with the side faces bisected on the square diagonal, and twisting the top, usually by 180/q degrees in the same direction, causing side triangles to be concave.