We prepared an all-solid-state reflectance-type electrochromic device (ECD), consisting of the following five layers: Al/WO(3)/Ta(2)O(5)/Ir(x)Sn(1-x)O(2)/ITO. Using RF ion plating, we prepared a film containing dispersed iridium oxide in a tin oxide matrix; this film acts as the counter electrode in the all-solid-state ECD. Protons were used as coloration ions in the ECD. The size of the ECD was 150 cm(2), and the reflectance changed between more than 60% from 15%. The coloration and bleaching response times were less than a few seconds. We analyze the optical characteristics of the ECD, and report the results of a consecutive drive test and a high-temperature heat resistance test. (C) 2010 Elsevier B.V. All rights reserved.