The first order Freedericksz transition at saturation point for weak anchoring NLC cells

On the basis of the modified Rapini-Papoular expression for the anchoring energy, the properties of the transition at saturation point for weak anchoring NLC cells has been studied analytically. We find that this transition may be of second order, as is usually predicted by many authors; however, it may also be first order. Whether it is first or second order is determined by the material, anchoring energy and thickness of the cell. The conditions for first order transition are deduced by an analytical method, and the results of calculation are shown by graph for κ (= K ₁₁ / K ₃₃ ) values 0.8, 0.6 and 0.4. The saturation field strengths for the first order transition case are calculated and shown in the table.