An external microcavity structure was introduced to the stacked cathode in organic light-emitting devices (OLEDs). and its influence on the luminescent characteristics was investigated. From the detailed optical analysis that was conducted. it was found that the surface plasmon loss in a metal cathode can be reduced to about one-fifth by using a semi-transparent thin-film cathode. https://midwaysportes.shop/product-category/sunglasses/