Digital optical display with magnetic code plate indexing

A digital optical display device incorporated in a scale including a movable measuring member, a code plate with opaque and transparent areas, a stationary light source irradiating the code plate, a seven-segment display adjacent the code plate and having light guide inlets receiving the coded light transmitted through the code pattern on the code plate, a magnetic indexing system associated with the code plate and defining a multiplicity of magnetic indexing locking positions arranged in step by step relation to each other to retain the code plate in any of the multiplicity of discrete positions; a spring coupling between the measuring member and the code plate and yieldable within one magnetic index position of the location at which the measuring member has stopped to locate the code plate at the position of a discrete code pattern.