Water pollution detector using diffusion-meter - uses photocells measuring direct and diffused light transmission paths

摘要

The turbidity of sea or fresh water is measured by a diffusion meter in which the direct and diffused transmission paths for a light beam are measured. This allows weight of phyto plankton to be determined as well as natural or other causes of pollution. A red LED acts as a luminous source and is located behind a diaphragm (D1) which is located in the focal plane of a lens (L1). This assembly is housed in an enclosure (8) attached by a flange (10) to an electronic equipment enclosure (9) containing temperature and pressure sensors. The LED beam passes through the medium being measured to a second lens (L2) in front of which is a diaphragm (D3) which defines the quantity of water. Another diaphragm (D2) defines the beam diameter and the transmitted and diffused light is detected by photodiodes.