| 摘要 |
An electrochromic arrangement particularly useful in a region of the infra-red spectrum above 3 microns comprises in order a rear glass substrate (1), a film electrode (2) with an IR reflectivity of at least 50%, an ion storage layer (3) an ion conducting layer (4). An electrochromic tungsten oxide layer (5) having at least a degree of crystallinity, a silicon front electrode (6) and an antireflection coating (7). In the uncharged state of layer (5) all layers (3-7) are transparent and most incident light is reflected at (2). On entering the charged state the layer (5) exhibits a marked increase in light absorptivity and refractive index. In a device incorporating a bare layer (5) the latter causes such a large increase in reflectivity at the front surface that the increase in light absorption tends to be masked, with a resulting increase in reflectivity of the device. Layer (6) acts as an index matching layer (6) whereby less light is reflected at the front of layer (5) and more light is transmitted through to be absorbed in charged layer (5) in both directions of transmission, so decreasing the reflectivity. |
