TFEL EDGE EMITTER STRUCTURE WITH UNIFORM LIGHT EMISSION FILTER

摘要

W.E. 55,471 A TFEL edge emitter structure with an EL stack having a linear array of spaced-apart pixels with front edge faces emitting light of non-uniform intensity from different regions has an uniform light emission filter provided across the light-emitting faces of the pixels. The filter takes the form of an exposed photographic emulsion coated directly to the light-emitting faces of the pixels. Alternatively, the filter takes the form of a separate substrate containing the exposed photographic emulsion mounted across the light-emitting faces of the pixels. The exposed emulsion is darker at regions thereof which correspond to regions of the light-emitting edge faces of the pixels with higher original light intensity and lighter at regions thereof which correspond to regions of the light-emitting edge faces of the pixels with lower original light intensity. The final exposed emulsion reduces the original non-uniform intensity of the light from the different regions of the pixel light-emitting faces to an uniform level equal to that of the lowest original light intensity of the pixel light-emitting faces. A focussing lens can be combined with the edge emitter structure. The filter emulsion is exposed so as to compensate not only for non-uniformity of light intensity of the structure but also for optical nonuniformities of the lens.