Comparison of some characteristics of thin‐film‐electroluminescent ZnS: Er, F planar and edge emitters

— The following main differences have been revealed in the characteristics of an edge thin-film-electroluminescent ZnS: Er,F emitter compared to those of a similar planar emitter: (1) the 1.535-μm band more highly dominates over other bands in the EL spectrum; (2) the voltage (V) dependence of the intensity of this band is the strongest; (3) the 1.535-μm band narrows with increasing voltage and its frequency. The above differences are explained, firstly, by smaller optical losses in the ZnS: Er,F film for the near-infrared emission than for the visible one and, secondly, by an optical amplification over the 1.535-μm band in the edge emitter.