Liquid
levels can be measured simply and accurately using infrared
light, without the need for any electrical or thermal
connection between the target and the medium. The operating
principal is illustrated in the diagram on the left.
The ratio of reflective indices changes, depending on
whether the tip of the sensor is surrounded by liquid
or air. If the sensor is immersed in liquid, the light
rays will be deflected into the liquid and the electronics
of the received changes its switching state. |
