| 摘要 |
<p>A liquid crystal visual display device (1), e.g. a thermometer, comprising a number of overlying layers (8-10, 12-14) of liquid crystal material, each activatable to change colour over a different temperature activation range, and an optical filter (7, 11). The layer or layers of liquid crystal material overlying the backmost layer (10, 14) are sufficiently transparent to enable an underlying temperature activated layer of liquid crystal material to be visible therethrough.</p> |
