Abstract: A reversible electrodeposition electrochromic infrared modulator for modulating infrared energy is provided. The modulator includes a working electrode having an infrared transparent substrate with first and second major surfaces. A conductive layer is disposed on the second major surface of the substrate. A counter electrode is spaced from the working electrode and a sealing assembly hermetically seals the working and counter electrodes with a cavity defined therebetween. An electrolyte material containing an electrochromic material is disposed within the cavity. A reversible power source is coupled to the working and the counter electrodes for providing a reversible voltage potential between the working and the counter electrodes. A thin film of the electrochromic material plates the conductive layer of the working electrode in response to an on state voltage potential between the working and the counter electrodes.