| 摘要 |
<p>A detector (15) for detecting the presence of ice, water, mist, frost or other solids or liquids on a sensing surface (14) is provided. The sensing surface (14) is provided by a medium substantially transparent to electromagnetic radiation and solids or liquids are deposited on the surface. A transmitter directs radiation onto the surface and a receiver is responsive to radiation reflected from the surface. A discriminator circuit receives an output from the receiver and provides an output indicative of whether a solid or a liquid is present on the surface.</p> |
