| 摘要 |
<p>A device (1) for providing a visual indication of the level of liquid contained in a container having walls (11) with good heat conducting properties comprises a number of temperature-sensing strips (3-7) each including at least one liquid crystal composition. The temperature sensing strips exhibit colour play over a plurality of narrow, spaced apart temperature ranges selected so that at least one strip will exhibit colour play when detecting a temperature gradient on the external surface of the walls (11) of the container. Such a temperature gradient occurs adjacent the level of the contained liquid as a result, at least in part, of vaporisation of the liquid occasioned by withdrawing some of the contents from the container.</p> |
