Abstract— The first commercial use of the Zenithal Bistable Display (ZBD™) is for electronic point‐of‐purchase (epop™) signage in the retail sector. As a reflective bistable display, this novel LCD technology only consumes power if new information is required and the image is updated. This allows complex images to be shown constantly for several years from the energy of a single low‐cost battery, when the display is updated up to ten times each day — ideal for signage applications. Excellent performance characteristics are achieved in a TN‐like STN‐LCD in which one of the alignment surfaces is a relief grating. Correct design of the grating shape and surface properties not only imparts the bistability, but allows control of the optical performance, the latching voltages, and the temperature range. Being addressed using a simple passive‐matrix approach, without the need for a thin‐film‐transistor backplane, large amounts of information may be displayed by STN drivers. Alow‐cost fabrication method has been devised that is compatible with conventional TN and STN manufacture, and with negligible equipment outlay. The device operating principles, manufacturing method, and performance of ZBDs are reviewed.