Ion Depletion Projection Display
Original Publication Date: 1987-Nov-01
Included in the Prior Art Database: 2005-Feb-02
This article describes a display provided by an array of cells, the index of refraction of which is varied by selective application of electric fields. As shown in the figure, the operation of the display is by variation of the ion concentration in an array of fluid-filled cells 10, 12 so as to switch them selectively between states in which they provide a total internal reflection interface with a plate 14 and in which they do not. The index of refraction of a solution is, among other factors such as temperature, dependent on the concentration. If the solution in the cells is ionic then an electrostatic field can separate the ions and, more importantly collect them as a wall charge on a dielectric. This depletes the concentration of the solute in the bulk of the solution.